same: jul 2010

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010 1

2 THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010 �

Chris ReayChairman of the Working

Committee: Communications(SA Institution of Mechanical

Engineering)

AN ENGINEER’S VIEW

The World at Large

In the USA it is estimated that some 30% of homes have mortgage liabilities that exceed the value of the assets themselves. Millions of toxic loans comprising the structured invest-

ment vehicles of securitized assets whose values cannot be determined remain in the system as do the credit default swaps, the ultimately crazy and disastrous process of gambling with insurance products on assets you do not own. And Europe now shows serious bankruptcy cracks.

A well-presented explanation of the build-up and collapse of the world credit markets is provided in a book called the Perfect Recession which shows the analogy with the causes of the Perfect Storm that destroyed so much of the east coast of the USA in 1991. It identifies the coincidental phasing of some 12 independent effects, that happening on their own, would normally pass by unnoticed.

How should South Africa emerge from the recession? Investec convincingly pointed out that unemployment was our biggest threat, a feature that we have to solve ourselves. No bailout is available for that. How well are we creating an environment that encourages the entrepreneur and the small businesses that are the backbone of growth in any economy? If South Africa were in effect a business corporation, would you invest in it when presented with some of the following attributes in a strategic plan?

The Planning Commission believes it is acceptable to have a two-and-a-half year sabbatical before it needs to put any plan forward (one year to form, 18 months before delivery). An integrated energy policy, crucial to confidence and forward planning, does not exist. So what do we have to consider?

Hire and fireLabour market and labour laws: most employers try to automate where they can to eliminate labour that has first world rights in a third world environment. No hire and fire here that built most successful economies. Competitiveness: low down on the world scale and dropping. Education of citizens: like the curate’s egg, good in many parts, horrible in many others. Our private schools are as good as

you can get, and need to be nurtured to keep that standard. Many government schools in general need a big kick just to get the teachers to class in time. Even the Minister is shocked, and that says something. En-ergy and power: per the new Eskom edict, the 25% increase will now happen 5 years in a row. Plug that into your cost planning. Effective skills development: blank screen. Some skills are marginally available while the world recovers and many projects end in South Africa.

I place Engineers as a business and interact every day with employers and candidates; if you are not relating to your future skills need, you may be in trouble because the really good ones are still scarce. Too many employers of engineering resources believe Mr Perfect is waiting on the street corner for the call. The huge intellectual capital tied up in retired-age Engineers remains unutilised due to a belief that these skills reside in the 30 to 50 age category. We need more effective Candidate Engineer training and paid mentoring as well as a lot more CPD than the minimum required for registration credits to help keep the institutional memory in the system.

Big hopeThere is big hope for tourism. The World Cup was great event and I believe we have done well against the forebodings of many critics. It could do wonders for putting us on the map, perhaps bringing skills (back) into the country, but we have to energise ourselves beyond the revenues of tourists. Will the intangible benefits of exposure and national identity outweigh the massive cost to South Africa of the event?

We need a game plan as a country. Where is it, Mr President and Mr Manuel? Let us not find that while we survived the recession, we lost the way to compete in the recovery.

A recent presentation by Investec Bank on the status of the world economy and the investment position shows that SA is in a lot better condition than many developed and emerging economies. Thankfully, whether by design or not, we were

saved from the direct effects of the credit crisis by the Credit Act, our traditionally high but realistic interest rates and rela-

tively conservative banking system.

Our private schools are as good as you can get, and need to be nurtured to keep that standard

� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010

International Trade Fair for Moldmaking andTooling, Design and Application Development

afrimoldAugust 16 – 18, 2010Johannesburg, South AfricaSandton Convention Centre

Visit w

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.com

to

pre-re

gister

and fo

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er in

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New to Africa!DEMAT GmbH (Direct Exposition Managing and Trading), owners of the highly successful Euromold, proudly presents afrimold, a unique opportunity to connect with Africa’s top toolmakers.

afrimold exhibition hall – PLUS - 3 day technical conference

The entire spectrum of moulds and tools including related technologies such as - rapid prototyping and rapid manufacturing will be highlighted.afrimold will provide a unique event experience by connecting buyers and sellers to all aspects of the product development lifecycle.

You will find solutions for:Automation Equipment, CAD/CAM Systems, Cutting Tools, Data Management Software, EDM Equipment, Hot Runner Systems, Machining Equipment, Tools & Accessories, Maintenance Equipment, Mould Bases, Mould Components, Mould Design & Engineering Equipment, Mould Handling and Storage Equipment, Mould Materials, Mould Design, Build and Repair Services, Inspection/Measurement Equipment, Rapid Prototyping/Tooling Equipment, Surface Treatment Equipment & services and more…………

Times: 16 August: 10h00 – 19h00 17 August: 10h00 – 19h00 18 August: 10h00 – 18h00

For further information contact:Ron MacLarty at afrimold on +27 (0) 72 353 6699 email: [email protected]

Or

Denis Goffinet on +27 (0)79 190 9805 email: [email protected]

Johannesburg

SA Plasticswww.saplastics.co.za

Endorsed by:

Media partner:

The Toolmaking Association of South Africa (TASA)www.ntipweb.co.za

297x210 VIS ad SA Mech.indd 1 5/17/10 8:01:04 AM


Cover Story9 Uniting in Business

Monthly Column11 Money on The Water

Compressors, Air, Vacuum Pumps15 Blowing in The Wind17 So Much More Control

POWER GENERATION TODAY21 A Biogas Project24 Power Generation News

Letter to the Editor26 Every Tom, Dick and Harry

Produced by:PROMECH PUBLISHING,P O Box 373, Pinegowrie, 2123Republic of South AfricaTel: (011) 781-1401, Fax: (011) 781-1403Email: [email protected]: www.promech.co.zaManaging Editor Susan CustersEditor Kowie HammanAdvertising Pauline BouwerCirculation Catherine MacdivaDTP Zinobia Docrat/Sanette LehanieDisclaimerPROMECH Publishing and The South African Institution of Mechanical Engineering as well as any other body do not take responsibility for the opinions expressed by individuals.Printed by: Typo Colour Printing, Tel: (011) 402-3468/9

Official Publication ofTHE SA INSTITUTION OF MECHANICAL ENGINEERINGand endorsed by:

CORROSION INSTITUTE OF SA SA PUMP MANUFACTURERS ASSOCIATION SA VALVE AND ACTUATORS MANUFACTURERS ASSOCIATION THE SA INSTITUTE OF TRIBOLOGY NUCLEAR INSTITUTE SA INSTITUTE FOR NON-DESTRUCTIVE TESTING NATIONAL SOCIETY OF BLACK ENGINEERS INSTITUTE FOR CERTIFICATED MECHANICAL AND ELECTRICAL ENGINEERS SOUTH AFRICAN ASSOCIATION OF CONSULTING ENGINEERS ASSOCIATION OF SOCIETIES FOR OCCUPATIONAL SAFETY AND HEALTH

Hydraulics & Pneumatics29 Water Works Deep Down31 Controls on the Way

Heating & Cooling33 Turning Up the Heat36 Keep Your Cool

Regulars3 An Engineer’s View6 Institution News38 SAIT27 Nuclear Institute (SA Branch)40 Market Forum46 On the Move

Contents

The monthly circulation is 4 242

CopyrightAll rights reserved. No editorial matter published in “SA Mechani-cal Engineer” may be reproduced in any form or language without written permission of the publish-ers. While every effort is made to ensure accurate reproduction, the editor, authors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any consequences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

July 2010 VOLUME 60 NUMBER 7

Featured on the Cover

Bearings InternationalTel: (011) 345-8007Email: [email protected]

International Trade Fair for Moldmaking andTooling, Design and Application Development

afrimoldAugust 16 – 18, 2010Johannesburg, South AfricaSandton Convention Centre

Visit w

ww.af

rimold

.com

to

pre-re

gister

and fo

r furth

er in

fo

New to Africa!DEMAT GmbH (Direct Exposition Managing and Trading), owners of the highly successful Euromold, proudly presents afrimold, a unique opportunity to connect with Africa’s top toolmakers.

afrimold exhibition hall – PLUS - 3 day technical conference

The entire spectrum of moulds and tools including related technologies such as - rapid prototyping and rapid manufacturing will be highlighted.afrimold will provide a unique event experience by connecting buyers and sellers to all aspects of the product development lifecycle.

You will find solutions for:Automation Equipment, CAD/CAM Systems, Cutting Tools, Data Management Software, EDM Equipment, Hot Runner Systems, Machining Equipment, Tools & Accessories, Maintenance Equipment, Mould Bases, Mould Components, Mould Design & Engineering Equipment, Mould Handling and Storage Equipment, Mould Materials, Mould Design, Build and Repair Services, Inspection/Measurement Equipment, Rapid Prototyping/Tooling Equipment, Surface Treatment Equipment & services and more…………

Times: 16 August: 10h00 – 19h00 17 August: 10h00 – 19h00 18 August: 10h00 – 18h00

For further information contact:Ron MacLarty at afrimold on +27 (0) 72 353 6699 email: [email protected]

Or

Denis Goffinet on +27 (0)79 190 9805 email: [email protected]

Johannesburg

SA Plasticswww.saplastics.co.za

Endorsed by:

Media partner:

The Toolmaking Association of South Africa (TASA)www.ntipweb.co.za

297x210 VIS ad SA Mech.indd 1 5/17/10 8:01:04 AM


THE SA INSTITUTION OF MECHANICAL ENGINEERING

Council 2009/2010

Office BearersPresident .......................... . . . . . . . . . . . . . . . . . . . . . . . . G Barbic (George)President Elect ........................... . . . . . . . . . . . . . . . ... D Findeis (Dirk)National Treasurer ................................. K Nyangoni (Kudzai)

Branch ChairpersonsCentral ..................................... . . . . . . . . . . . . . . . . . M Cramer (Mike)Eastern Cape ................................................ W Rall (William)KwaZulu/Natal ........................................... AG Fileczki (Alex)Western Cape ........ . . . . . . . . . . . . . . . . . Prof B Collier-Reed (Brandon)

Portfolios:Communications .............................................. CD Reay (Chris)Education - Universities................... Prof JL van Niekerk (Wikus)Education: Universities of Technology............... E Zawilska (Ewa)Membership .................................................... E Zawilska (Ewa)Seminars and Workshops.................................. D Findeis (Dirk)Technology Programme ................................. SZ Hrabar (Steve)

Chief Executive Officer: Vaughan Rimbault

National Office Manager: Anisa Nanabhay PO Box �11, Bruma, 2026Tel: (011) 61�-�660, Fax: (011) �88-��6Email: [email protected] Website: www.saimeche.org.zaMembership: Central, Eastern Cape & KZN: [email protected] Membership: Western Cape: [email protected]

Company AffiliatesAinsworth Engineering

Alstom Power Service SA

Babcock Africa Limited

Bateman Engineered Technologies

Bosch Projects

Fluor SA

GEA Air-cooled Systems

Hansen Transmissions SA

Hatch Africa

Howden Power

Howden Projects

Industrial Water Cooling

KHD Humboldt Wedag SA

Megchem Eng & Drafting Services

Osborn Engineered Products SA

Rotek Engineering

RSD a division of DCD-Dorbyl

S.A.M.E Water

Sasol Technologies

SEW Eurodrive

Siemens

SNC-Lavalin SA

Spicer Axle SA

Spirax Sarco SA

Thyssenkrupp Engineering

Transvaal Pressed Nuts & Bolts

Ultra-Flow Engineering Services

Vital Engineering

Weir Minerals Africa

Winder Controls

Do you know your BCEA from your LRA? A 1-day Practical Revision and Update on Key Labour Legislation

Introduction to Labour Relations IssuesIntroduction to the Basic Conditions of Em-ployment ActIntroduction & Update on the Labour Rela-tions ActDisciplinary Procedure RevisitedTermination of EmploymentMedical BoardingUse of Contract or Non-Permanent EmployeesRestraints of TradePersonal Performance Analysis

Seminar LeaderMartin Birtwhistle – HR Executive, Masonite (Af-rica) LimitedGraduate Degree: B Social Science (Industrial Psy-chology & Industrial Sociology), UKZN 1985Post Graduate Qualifications: Higher Diploma in Personnel Management - Wits Business School 1986Honours Degree in Industrial Psychology: UKZN 1989, LLM - UKZN 2009

For further details & registration form, contact: Carey Evans – National Events Department Administrator, Tel: (031) 764 7136, Fax: 086 671 6855, Email: [email protected]

••

•

••••••

“Key Labour Legislaton” SeminarDates: Durban – 13 August 2010 Gauteng – 16 August 2010CPD Validation Number – SAIMechE-0373-06/13


THE SA INSTITUTION OF MECHANICAL ENGINEERING

On Tuesday 25 May, the Central Branch of Saimeche hosted its annual general meeting which was very well attended despite the cold weather.

SAIMechE Hosts AGM at ECSA

President of SAIMechE, George Barbic, and past President, John van den Broeck

The audience listens to the presentation by Dr Ozzie Franks

National Treasurer, Kudzai Nyangoni and Chairman, Mike Cra-mer, taking questions from the floor during the recent SAIMechE AGM

National Treasurer, Kudzai Nyangoni, explaining the budget

Dr Ozzie Franks, CEO of ECSA, giving his presentation

Mike Cramer, Chairman of Central Branch Committee, chats to veterans Bob Baasch and Ludolf Meyer after enjoying refresh-ments

We were proud to be able to listen to Dr Ossie Franks, Ceo of ECSA, outlining his vision for ECSA in a presentation entitled “ Positioning ECSA to fulfil a broader role in South African society”.


PdMSA Conference First Predictive Maintenance and Reliability engineering – based maintenance (PdM) event for South AfricaA predictive maintenance and reliability engineering conference will take place on 1 and 2 September 2010 to offer solutions to industry hard hit by economic uncertainty and trying to cope with sharp cost increases and the need to improve productivity and uptime.

According to the organisers this will be the premier event in South Africa for Predictive Maintenance and Reliability Engineering-based maintenance (PdM). The two-day event comprises a conference offering more than 45 presentations by local and international experts and an exhibition aimed at personnel responsible for the reliability and avail-ability of equipment in the mining, utilities and industrial sectors.

Enormous pressure“Industry in South Africa is under enormous pres-sure to reduce costs and increase productivity and plant availability,” says Quinton Jones, full service manager of ABB South Africa. “This conference, jointly hosted by ABB South Africa with the largest condition monitoring consulting group in southern Africa, comes at the right time.”

Presentations will cover the latest technology and products available to the maintenance engineer to adequately predict the condition of the production plant, ensuring that maintenance personnel can be forewarned with the knowledge to effectively execute planned maintenance with minimised costs. The exhibition areas will showcase pre-dictive maintenance technologies, products and services.

The event is sponsored and hosted at ABB South Africa’s energy efficient premises in Longmeadow, Johannesburg, with “The SA Mechanical Engineer” as a media partner. Three tracks will accommodate electrical and mechanical aspects of the business. Continuing Professional Development (CPD) vali-dation points accompany this event.

www.abb.com/za

Professional opportunitiesOur job board continues to display a wide variety of excellent job positions that you can review and apply for on- line. Keep your credentials on our secure and confidential database, update them at any time.

We keep in touch with you.www.engineerplacements.com

Engineer Placements


COVER STORY

Bearings International in Elandsfontein near Johannesburg has addressed this develop-ment on various fronts. To learn more about their approach, “SA Mechanical Engineer”

speaks to managing director, Tony Patten. “We’ve been training customers’ staff for many years, both on the technical and store management side, but now we also train staff of companies that don’t even deal with us directly,” he says. “In addition, we mentor small black businesses who have partnered with us as suppliers to the mining industry.

Training“In fact, last year we trained a record number of customers and we’re already fully booked for this year,” Tony continues. “We’ve also just signed a deal with a big distribution and warehousing company to put 200 people through our four-month appren-ticeship course. Our heavy investment in training material, not only to train people about our products on the technical side, but also in storemanship, general warehouse management and sales, has certainly paid off.”

Consequently, training has become a major source

Uniting in BusinessThe face of business in the South African industrial sector is gradually changing, not only as a result of the shortage of engineering skills, but also because everyone is striving for better production efficiency in order

to compete globally. Suppliers know their products best and end-users are increasingly relying on suppliers to play an active role in streamlining plant operation.

of income for Bearings International. “Increasingly customers, like the mines, are including training as part of the supply contracts they sign with us,” says Ian Robertson, director of bearings. “Like our customers, we’re all suffering from the shortage of young engineers and we’ve now started bringing

back engineers who are on the ‘wrong side’ of the age bracket so that they can mentor the younger generation who simply don’t have the application experience.”

ExperienceIn light of the clever fake bearings that are increasingly appearing on the market, ap-plication experience is becoming an absolute necessity today. “Where in the past we had the Chinese copying main brands from Europe and the USA, we now also have them copying the good brands from China,” says Tony.

“Pirated goods are often so well disguised that only expert laboratory tests will reveal them to be fake. Together with KML in China, we developed a highly specialised bearing, for instance. Suddenly we started getting reports of one failure after another, only to find that the end-user had unknowingly bought the cheap fakes, thinking them to be the real thing.

Mainstream“A while back this problem was on the fringes

Tony Patten, managing director of Bearings Interna-tional

Now started bringing back engineers who are on the ‘wrong side’ of the age bracket

Together with KML in China a highly specialised bearing was developed


COVER STORY

of our industry, but it has since worked its way through to even some of the bigger bearing distributors in South Africa,” adds Tony. “The problem is two-fold. Firstly the lead times from the mainstream manufacturers are still very long and secondly, the counterfeits are getting harder to identify.

“The fakes are offered as a first tier product far below the price of the original bearing, leaving the supplier with a very tempting profit margin. In the past, we would suggest that people buy only from authorised dealers, but even this is no longer enough. You should only buy from ISO 9000 compliant

suppliers because then you have full traceability of the product. If there is any doubt, the customer should involve the dis-tributor or even the OEM.”

New business modelsBearings Interna-tional represents a wide range of power transmission prod-ucts which it sells through various business models. “We already have two independent companies that op-erate under this new model where we enter into a

business mentorship with a black-owned company,” explains Tony. “The Dti’s BEE score card does not level the playing field for all.

“The mining charter, for instance, does not recognise the broad based approach to BEE and therefore we started looking at the right entrepreneurs to interface directly with the mining companies,” says Tony. “We have two models in this respect. One is where we still have a stake in the business such as our current arrangement with Arrow Bearings and Transmissions in Witbank. Or the entrepreneurs operate independently as is the case with Nkwe Industrial and Mining Supplies in Rustenburg.”

However, the responsibility for guarantees, service, ISO compliance and support still ultimately remains with Bearings International.

Interface“In Nkwe’s case we enter into a formal enterprise development support contract where we work through them with the mines,” explains Tony. “They

Ian Robertson, director of bearings at Bearings Inter-national

get the vendor approval of the mines and we play a business mentorship role outlined in a formal, documented agreement which is maintained on a score card basis. Through this agreement we provide them with product training, joint calls to customers and technical support.

“It was not easy finding an independent company to operate as an interface with the mining companies, but in this case we’ve hit on a team of business-persons who have serious intentions to build up a good independent business,” Tony says. “Although by agreement we don’t have a share in their busi-ness, we benefit with a small margin on the profit, but most importantly, it gives us more legs in a field where it has become very difficult to do business in terms of BEE requirements. The challenge we’re now facing is to find more companies that are serious about building an independent business.”

PartneringEnd users who deal with these ‘satellite’ companies are well aware that they’re in fact dealing with Bearings International indirectly and can expect the same service and support they’ve always enjoyed from them. “Even with this extra link in the chain, it has become more important for end users and suppliers to work closely together than ever before,” Tony says in conclusion.

“Partnering with each other in terms of solutions holds huge benefits for the end user. We’ve just been credited with saving an iron ore mine 16 million rand a year with a drive solution we customised to their specific application. Our intent to remain a major product and solutions provider in South Africa is reflected in our new dedicated offices and warehouse facility we’re currently building in Boksburg.”

Tony Patten, Bearings International, Tel: (011) 345-8007, Email: [email protected]

The fakes are offered as a first tier product far below the price of the original bearing

The counterfeits are getting harder to identify


The only obstacle in some cases is infrastruc-ture facilities such as large dry docks and floating docks that would allow work on large vessels that currently sail right past

our shores to Asian shipyards. “SA Mechanical En-gineer” visits Dormac’s shipyard in Durban harbour to speak to Gary Pulford, international marketing and sales manager about the slumbering potential of the South African ship repair market.

Perfect placement“It’s already happening in Walvis Bay,” he says. “The Namibian government’s support to develop Walvis Bay harbour into a major repair facility is now taking a huge slice out of repair work that could have come to South African ports if we’d had government support in terms of the necessary docking facilities.

A potential source of foreign exchange for South Africa is sailing along our coastline

everyday on its way to a shipyard thousands of kilometres away in Singapore or China

where repairs will be undertaken that could very well have been done right here. Not only are large vessels being built in South African shipyards, we also have the skills and expertise to repair and overhaul large ships, oil rigs and other specialised ocean

craft.

“We’re in an ideal geographical position for passing trade, but we lack facilities such as dry docks,” explains Gary. “For many years we’ve been trying to build our own, but in spite of offering to fund the building of a graving dock, the authorities just don’t seem to see the benefits in encouraging more vessels to come to South Africa for their repairs.

Excellent vehicle“At the moment, even when business is slow, we’re turning around four projects a week, averaging around 500 000 US dollars per project,” says Gary. “It’s also an excellent vehicle to train and employ technical people of all trades. On a recent big Chevron project of 17.5 million US Dollars, for example, we inducted 2 000 people and at any one time had at least 1 000 people employed on the project.

“The Escravos is Chevron’s floating production and storage facility for LPG gas. The project was handled by our Cape Town branch because Durban’s dry dock isn’t big enough to accommodate her. Gas is pumped to this facility where it is frozen and stored for transhipment to vessels that deliver the gas across the globe.”

The projectThe scope of work on this project included the onboard fitting of a 150 tonne generator complete with the supply and fitting of new cables,” explains Gary. Other work involved overhauling of the cryo-genic valves, sea valves, electric motors, fans and pumps. Two lifeboats were removed, fully painted, tested and re-fitted.

Dormac’s blasting and painting division completed a total of approximately 15 000m² which consisted of the hull and deck areas

Money on The Water

MONTHLY COLUMN

For many years we’ve been trying to build our own


“We also assisted crews from the various manufac-turers involved in the project such as Rolls Royce for the generators, Appleton’s cranes, Alfa Laval

for the coolers, Aalborg boilers and Terrasaki and Konesborg who did all the electrical work.’

PaintingDormac’s blasting and painting division completed a total of approximately 15 000m² which consisted of the hull and deck areas. “Blasting was done on the deck, accommoda-tion units, ” adds Gary. To successfully complete the blasting and painting, the accommodation had to be fully staged, high pressure cleaned and painted. In total, the work scope for the blasting took six days and then seven days to complete the painting.

“Our machine shop assisted with the overhauling and

MONTHLY COLUMN

Dormac’s blasting and painting division completed a total of approximately 15 000m² which consisted of the hull and deck areas

We are particularly proud of our safety performance on this job

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010 1�

Oil rig servicing holds huge business potential for South Africa

fitting of the Sofec swivels that are attached to the turret onboard,” explains Gary. “The swivels were transported from Cape Town to Durban by road to be cleaned and overhauled prior to being fitted with new seals and bearings, re-assembled and pressure tested. The overhead turret units were fabricated in Durban and returned to Cape Town as well.

Award“This project was the 4th in the off-shore market and we are particularly proud of our safety performance on this job,” adds Gary. “We were given a R150 000 award by the client for our safety performance and we decided to match it by structuring the award as an incentive to the workers where any contraventions would be subtracted from the lump sum.

“All the workers participated eagerly and a very small amount for minor contraventions was de-ducted, so that we could donate R300 000 to the Carte Blanche fund.”

A firstAnother feat we’re particularly proud of is when Dormac Walvis Bay branch made marine engineering history late last year. The company became the first to pull a propeller shaft of a general cargo vessel while afloat alongside in the port. “The bearings in the main engine started running hot while en route from Matadi, the vessel’s previous port of call,” explains Gary.

“The owners approached us about correcting the problem without having to go through a costly towing exercise to get the vessel to the dry dock in Cape Town. Our solution made Dormac the first company to successfully pull a propeller shaft off a general cargo vessel while afloat alongside in a port.

How it was done“The tail shaft has a diameter of approxi-mately 600mm with a mass of approximately 13 tonnes,” elaborates Gary. “The intermediate shaft between the engine and tail shaft was first removed inside the vessel and then rigged out of the way. The 15 tonne propeller was removed from the end of the tail shaft and rigged ashore. The tail shaft was then rigged into the vessel and blanking plates were fitted onto the outside and inside of the stern tube to prevent ingress

MONTHLY COLUMN

of water into the engine room. The vessel was then towed to the anchorage where the old stern shaft bearings were removed.

“The work was done by flooding the vessel’s forward ballast tanks, thereby lifting the stern partially clear from the water. With the stern lifted clear from the water, the vessels propeller could be taken off so that the shaft could be pulled into the engine room. When the shaft was pulled out, the technicians could reach the two main bearings while keeping the shaft in place.

Training“Apart from South Africa’s perfect location for this kind of work we have proved over the past couple of years that we can do it to world class standards and at attractive pricing,” says Gary in conclusion. “Our opposition is up in Asia and if we can save an owner in terms of towing costs, production time and quick repair time, we can attract a lot more work to South African ports. In addition, the ship building industry offers a huge scope for training in all the engineering trades and can only help alleviate the employment problems of the country.”

Gary Pulford, Dormac, Tel: (031) 274-1500. Email: [email protected]

The first to pull a propeller shaft of a general cargo vessel while afloat alongside in the port

1� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010

Potentional For GrowthSouth Africa holds major potential for investment in the mould-making, tooling, design and application

development industries which are vital components of manufacturing products for both local and export markets.

“There is an urgent need to boost this area of the South African economy,” says Ron MacLarty, man-aging director of the new Afrimold Exhibition taking place at the Sandton Convention Centre from 16-18

August.

Ron is concerned that mould-making, tooling and design are skills that have been dwindling in South Africa. “We need to boost this area of our manufacturing sector with new technology and at the same time underline its importance within our overall economy because literally nothing can be manufactured without a mould, tooling and design.”

Successful showingThe afrimold Exhibition in Sandton is being organised by Direct Exposition Managing and Trading (DEMAT), which hosts the long-established and hugely successful EuroMold show in Germany. The show concept has also been success-fully taken to North America, India, Russia and China.

Jim Plester of Machine Simulation SA, which holds the agency for C G Tech Vericut CNC machine simulation, verification and optimisation software technology and for Dassault Systèmes Product Lifecycle Management portfolio including Catia, Delmia, Enovia SmarTeam and 3Dvia. Says, “The Afrimold Exhibition is long overdue. “We see the show as not only a great opportunity to demonstrate the power of our software technology and an opportunity to generate new business, but also as a platform for much-needed development of local skills and employment and career opportunities in mould-making, tooling and design.”

A priorityRetecon is another exhibitor that sees the development of skills as a priority for the industry in South Africa. Managing Director Hans-Peter Neth says, “We also support initiatives to raise skills levels generally in the machine tool industry, which is a critical factor in the success and growth of the local manufacturing industry in the production of a wide range of added value products.”

Ron MacLarty, Afrimold South Africa, Tel: 072-353-6699, Fax: (086) 516-2975, Email: [email protected], Website: www.afrimold.com

We need to boost this area of our manufacturing sector


Poorly-designed distribution networks, neglect and little or no maintenance not only results directly in waste, but inferior quality air delivered to the final point of use, causes

unseen damages to precious pneumatic machinery. It defeats the purpose if you invest in high preci-sion CNC machinery, for example, only to drive its pneumatic system with compressed air full of dirt and water that causes premature wear through dirt

Blowing in The WindCompressed air is daily becoming a more

precious utility, yet it’s being wasted copi-ously, not only through leaking pipes, but

also through indiscriminate use.

building up in moving parts of the machine.

Flooded“Very often it’s the small things, which can usu-ally be easily fixed, in an air system that people neglect,” says Nelson Paulo of Airforce Compressors in Boksburg when “SA Mechanical Engineer” joins him to talk air systems. “The market is flooded with companies selling compressors, but there are not many who provide the backup service to ensure proper installation, repairs and spare parts for the machines they sell.

“A compressed air piping system, for example, is not something you let the plumber down the road do for you,” Nelson says. “It has to be planned and

installed with the right fittings, water traps and necessary drier equipment to ensure you get the quality air required by the equipment. I often come across installations where they run the danger of losing the warranty on an expensive CNC machine purely through dirt and water in the air seriously hampering the operation of the machine. In some instances, such as a car spraying plant, insurance will insist on inspecting an air system as it plays a direct role in the quality of work delivered.

Quality air“Not everybody can afford, or in fact re-quires an air dryer, but there are ways of extracting water effectively, for instance, from an air system simply by routing the piping so that traps and drains can be installed at strategic points,” adds Nelson.

“Another huge waste is the indiscriminate use of air to do things like ‘sweeping’ the floor or cleaning dust off worker’s clothes. We’ve just had a client where it was normal practice for workers to dust themselves with an open-ended air hose every now and then. We fitted proper air dusters and saved the client a huge amount in energy consumption.”

SizingOne of the biggest errors made when it comes to purchasing a compressed air system is under sizing the compressor. “Under sizing a machine is very common, especially up here on the Reef where

Having stock and spare parts is a differentiator in the competitive compressor industry

Piston compresors must have a chance to rest during the day’s run

Not something you let the plumber down the road do for you

COMPRESSORS, AIR, VACUUM PUMPS


you immediately lose 10% on a machine usually specified at sea level,” says Nelson. “When it comes to piston compressors, users don’t consider the machine’s duty cycle and then they buy a machine which is in fact undersized.

“The first thing we look at is the duty cycle of the

Nelson Paulo of Airforce Compressors

machine. It’s not advisable to buy a compressor that exactly fits the capacity requirements of your machinery because even if it delivers to capacity, it means the compressor will be running all the time and have no time whatsoever to rest, caus-ing premature wear,” adds Nelson. “You have to factor in things like duty cycle, possible leaks and peak demands.

“A piston machine, for example, needs time to cool down which has to be factored in as well. We just installed a second machine for a factory where they kept on running out of air at certain times. The second machine is on variable speed and only kicks in when demand increases to peaks at certain times. This reduced the strain on the main com-pressor and completely eliminates downtime which the client used to experience while waiting for the compressor to ‘recover’ from a long run.”

ServiceOne of the problems with the flooded market is that compressors are not repaired or overhauled any more. “Rather than overhaul, customers outright replace a broken down machine with a new one because there are so many cheap products avail-able,” says Nelson.

“From experience we’ve learned that not all Chinese products are cheap and nasty, but it takes time to sift through the inferior stuff and find suppliers of good reliable machines. To this end, we’ve now established our own quality control procedure and have narrowed our Chinese suppliers down to a few who build good copies of proven designs at high quality standards.”

SparesIn spite of the trend not to overhaul, Airforce has kept a workshop and repair teams going through the years and today this distinguishes the company from the many suppliers out there who only supply and don’t even carry spares for the machines they import. “You also get those who sell cheaply just to get the machine into the market and then you pay through your teeth to get spares that have to be imported,” says Nelson in conclusion.

“As a rule of thumb anyone who buys a compressor today should, on the spot, ask about the availabil-ity and costs of spares such as gaskets, conrods and pistons for that particular machine. Or you can go the route of some mining companies that actually invest in spare parts the day they buy a new machine.”

Nelson Paulo, Airforce Compressors, Tel: (011) 894-8234, Email: [email protected]


It was normal practice for workers to dust themselves with an open-ended air hose every now and then


“SA Mechanical Engineer” speaks to Mark Burn, product specialist at Air & Vacuum Technologies in Midrand, about trends in this industry. “Variable speed drives are

not new as such, but are suddenly catching on in South Africa,” he says. “Lately we’ve been fit-ting VSD drives to most of the pump installations we’ve done. It just gives you so much more control over the system which can save a huge amount of electricity.”

So Much More ControlLike compressors,

vacuum pumps are greedy energy guzzlers, leaving

ample room for economising through professional design and

proper installation of the vacuum systems and the piping network.

With OEMs constantly working on better technology to optimise energy

consumption, it may very well be worth reviewing old vacuum pump installations in

this light.

Speed control“Speed control allows you to run oil lubricated pumps anything between 30 to 60 hertz and, combined with pressure switches in-line, you have

full control to slow down the pump when demand is low, or speed up the pump as demand increases,” Mark explains. “In addition, “new” oil free claw technology has been fine-tuned to a point where the pumps can operate with a much smaller motor. The energy required to run the same capacity pump is half of what it used to be.”

Vacuum systems are installed either as individual pumps at each application or you can have a centralised system with piping running to the various applica-tions. “Provided the installation is done properly, a centralised system can be more economical,” says Mark. “We’ve just done an installation where they had 30 individual pumps which we replaced with two big centralised pumps and a piping network.

Equal hours“The two pumps run on the lead-lag principle where one of the two is on standby while the other is running,” explains Mark. “However, they alternate automatically so that they’re working equal hours. This installation saved the


Many people underestimate the importance of the vacuum pumps on their plant

Mark Burn of Air & Vacuum Technologies

This installation saved the customer R30 000 a month just on maintenance


The TRVX range, made by Pompetravaini, is a single

stage, vari-ported designed liquid ring vacuum pump

that employs smaller motors and no water is needed

customer R30 000 a month just on maintenance while the return on investment is 18 months.”

The oil-lubricat-ed rotary vane v a c u u m p u m p s are de-s i g n e d and built by

Elmo-Rietschle and used in a wide variety of industrial applications. The l a r g -est range of o i l - f l ooded vacuum pumps for industrial coarse and fine vacuum operation is based on three different designs. The first is a compact range of pumps with overhung bearing


design while the medium range has rotors supported on both sides

including a flexible coupling arrangement. The large pumps are designed with rotors supported on both sides and have a flexible coupling as well as a double walled cyl-inder for additional

cooling.

Gas ballast valve

“Although the rotary vane vacuum pumps are air cooled in the standard version, an oil-water cooler is avail-

able for high ambient temperature conditions or

for heat recovery,” says Mark. “The exhaust air is cleaned

by a built-in mist filter with a very high separation efficiency

ensuring oil-free operation in all working conditions. Maintenance and filter change on these pumps have been simplified and can be

The old designs use copious amounts of water


carried out quickly. All pumps from 50m³/h up feature a gas ballast valve as standard allowing the optimisation of water vapour. When the pump reaches its operating temperature any water vapour pumped passes through as a gas, without condensing.”

Typical applications for these pumps include en-vironmental engineering as in aeration, drying and dust extraction. They’re also widely used in the food processing industry for bottling and filling machines as well as cutting machines. Industrial applications include industrial furnaces and vacuum hold down while all pneumatic conveying systems utilise vacuum.

Liquid ringOne of the most common vacuum pumps used in heavy industry is the liquid ring pump, but older designs especially use excessive volumes of water to operate. “We regularly come across very old liquid ring pumps that have been running for decades,” says Mark. “At the time these were the cheapest pumps you could buy and although they last very long, they’re certainly not the most economical to run. The old designs use copious amounts of water, they run on oversized motors and you also need cooling towers, fans and a water treatment plant, all just for the pumps.

“New technology in liquid ring pumps cuts util-ity costs dramatically,” adds Mark. “We’ve just completed a replacement installation where the end-user is saving R1.8 million a year in electricity and water costs alone. This was calculated from their actual figures over a period of time and is not just a theoretical estimate.”

Vari-portedThe series of pumps for this application, the TRVX range, is made by Pompetravaini. “This single stage, vari-ported designed liquid ring vacuum pump employs smaller motors and no water is needed,” says Mark. “Pompetravaini has been in the vacuum pump business for more than eighty years and, together with feedback and sugges-tions from end-users, they’ve come up with a new milestone in the design and manufacture of the liquid ring vacuum pump. The new hydraulic profile allows a performance increase of over 10% com-


The Elmo-Rietschle, used in a wide

variety of industrial applications

pared with traditional liquid ring designs.”

Other advantages include pump weight which on an average is 30% less than traditional designs while dimensions and volume is 40% less. It has single and direct service liquid connections and the central body impeller housing has integrated suction and discharge manifolds. This feature reduces pump components and increases robustness. The suction and discharge port plates as well as the impeller are made in stainless steel while the mechanical seals are standard and easily obtainable. The mechanical seals can be replaced without disassembling the pump, reducing downtime significantly.

Savings“Many people underestimate the importance of the vacuum pumps on their plant,” says Mark in conclu-sion. “Some don’t even know they have a vacuum system because it’s often tucked away in a corner somewhere out of sight and they only discover it when it stops working. It’s not only crucial to look after your vacuum pumps on a regular basis, but now, when everybody is looking at ways of saving energy, it may be worth evaluating your installation to see if new technology can save you money.”

Mark Burn, Air & Vacuum Technologies, Tel: (011) 318-3241, Email: [email protected]

Some don’t even know they have a vacuum system because it’s often tucked away in a corner somewhere


67682-Hytec Hydraulic AD.indd 1 6/15/10 4:37:04 PM


POWER GENERATION

Produced by:

PROMECH PUBLISHING,P O Box 373, Pinegowrie, 2123Republic of South AfricaTel: (011) 781-1401Fax: (011) 781-1403Email: [email protected]: www.promech.co.za

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DisclaimerPROMECH Publishing does not take responsibility for the opinions expressed by individuals.

Printed by: Typo Colour PrintingTel: (011) 402-3468/9

However, like all pioneering work, it wasn’t just plain sailing for the team of engineers who made this

project not only successful, but also established a model which many private and public organisations has since visited to see just how things are done.

“SA Mechanical Engineer” visits the site just off the Umgeni River near the city centre to speak to John Parkin, deputy head of plant and engineering at eThekwini municipality. “When facing such an unknown challenge you can either sit back and say it can’t be done, or you forge ahead and just do it,” he says with a smile.

“In spite of some serious setbacks, we persevered and got it right after six years of hard work.”

GreenhouseThis greenhouse gas project not only gets rid of the odour from the landfill site that used to drift over neighbouring residential areas, but it destroys methane gas which is harmful to the environment. “The natural decomposition process in a landfill produces methane, carbon dioxide and impurities such as SOX and NOX,” explains John.

A Biogas ProjectThe first power generation plant in Africa to successfully run purely on methane gas from landfill has now been operating for a year,

earning the eThekwini (Durban) municipality a modest 2.9 million rand a month (0,7 from

the sale of electricity and 2,2 from sale of carbon credits). The two plants, based at two different landfill sites produce 7.5 megawatt of electricity which is fed into the munici-

pality’s grid while the biggest spin-off comes from selling carbon credits to Europe.

John Parkin of the eThekwini Municipality

CopyrightAll rights reserved. No edi-torial matter published in “Power Generation Today” may be reproduced in any form or language without written permission of the publishers. While every effort is made to ensure accurate reproduction, the editor, au-thors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any conse-quences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

Three of the engine units at the generation site


POWER GENERATION

“Methane is 21 times more harmful than carbon dioxide and, for destroying methane in our process, we get paid for certified carbon credits that in turn are sold off to companies by a broker in Europe.”

Pipe work from the landfill site distronutes the gas to the engines directly

CreditsThe project kicked off with a World Bank search in Africa for a partner. Through the University of KZN, eThekwini got involved in this CDM (clean development mechanism) project. “As a developing country we could register with the UNFCCC (United Nations Framework Convention on Climate Change)

as a CDM project which allows us to sell the credits,” explains John.

“It does, however, take about two years before the money actually lands in the bank which presents a cash flow problem in the beginning.”

How it worksThere are a number processes that can be applied to use the gas that comes off a landfill site as a fuel for internal combustion engines, but it is not the same technology used for natural gas combustion engines, for instance. “We opted for the simplest process, but it is not that easy to manage,” says John.

“Basically you drill a hole into the existing waste, into which you put a slotted pipe. You surround this by stone to prevent the waste from clogging the slots and connect the pipe to a network that goes to the generator plant. Methane easily

flows downhill because it is heavier than air, so we put a small negative pressure on the pipe network to ensure a good flow to the plant, based below the level of the landfill.”

The hard wayAlong the pipeline there are tap-off points to drain any moisture that may have collected due to con-densation as the temperature of the gas drops from 50ºC when it comes out the well, to the ambient temperature of the pipe.

“This we also learnt the hard way,” says John with a chuckle. “If too much moisture gathers in the pipe, the Blower can’t suck the gas through which starves the feed and chokes the engine.”

The engineThe gas flow then goes from the blower direct to the engines in the engine room. “We use a GE Jenbacher 20 cylinder spark ignition engine that was originally converted from diesel engines but are now specifically built for gas,” explains John. “The gas is burnt as it comes from the well complete with impurities.

“Here again we learnt the hard way and blew one engine up in the beginning,” says John. “Our site’s gas has a particularly high silica content. As the gas is not cleaned beforehand, the silica crystallises and builds up in the piston chamber, reducing the volume and thereby causing the engine to overheat and burn the exhaust valves. We now have an alarm system that triggers when the build-up becomes

We opted for the simplest process, but it is not that easy to manage

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The power plant right next to the landfill site in the background

critical which is when we simply open the engine up and de-coke to clean out the silica caking on top of the pistons.”

PowerThe gen-set comes from the manufacturer complete with engine and generator, packaged neatly into a container with cooling systems fitted. Each generator on the seven engine units generates electricity at 400 volts. This is channelled through a transformer to step it up 11 000 KV before it goes through a switching room and from there straight into the grid. John adds, “Currently we have seven units like this running at the one site to generate 6.5 megawatt.

“When we started off there wasn’t a wide choice of engines, but today several manufacturers have conversions that run on gas,” explains John. “Ours were the first GE engines to come into the country and since then, the company has supplied similar engines that run on natural gas to a project in Mossel Bay. Natural gas engines are slightly different from methane engines, but they’re delivered ready to run. We just connect the gas line and the electrical side, and start up.”

The wellsThe landfill at the CDM project has 56 wells pro-ducing enough gas for the seven units to run with about 550 cubic metres per hour spare gas that is currently being burnt off. “Each engine requires around 500 cubic metres per hour so we have enough gas for another unit, but it is too close to the margin,” says John. “Gas supply from the 56 wells in the rehabilitated area of the landfill varies according to ambient temperature. In winter it drops significantly, even with Durban’s temperatures.

“Originally we only sunk vertical wells, but then tried horizontal wells into the sides of the landfill which produce a good steady flow of gas,” adds John. “The danger is the horizontal wells will eventually be crushed by the weight of the landfill, but we calculated that it won’t happen in this case before the site’s gas is depleted anyway. We’ve looked at the possibility of storing the gas, but it is tricky and very difficult and we’ve shelved the idea for the time being.”

The futureJohn has had people from all over Africa visit the site to learn from them and they don’t mind sharing their experiences with others. “We’re very satisfied with the project in spite of the hardships we had to conquer, but it’s a matter of forging ahead and just doing it,” he says in conclusion. “However, landfills do dry up and we’ve got to keep on searching for other ways of getting rid of waste. We’re currently

looking at other waste-to-energy technologies where we burn the waste directly for steam generation, for instance. Then we only have to move the ash to landfill sites that are getting further and further away from built-up areas,”

John Parkin, eThekwini Municipality, Tel: (031) 311-8820, Email: [email protected]

POWER GENERATION

This we also learnt the hard way

2� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010

POWER GENERATION NEWS

Simplifying management of open systemsHoneywell recently announced it has added several enhance-ments to its Experion Process Knowledge System (PKS) to help process manufacturers more easily and cost effectively manage their automation and control systems.

The Experion R400 includes advancements that lower the cost of open system ownership, thanks to features such as an extended support life, flexible direct on-process migration paths, virtualisation, and easier installation and migration.

In addition to these management features, Experion now also offers an integrated turbine control system that allows power generators to improve their plant performance through tighter integration between boilers and turbines.

“It’s no secret that the introduction of open systems brought both great benefits as well as significant challenges to the processing industries,” says Scott Hillman, global solutions director for Honeywell Process Solutions. “The enhancements we’ve made to Experion are designed to help alleviate most of those challenges by giving plants an easier and much more cost-effective way to keep their operations running smoothly.”

Operating Experion in a virtual environment, for example, can greatly reduce the number of PCs needed at plants, simplify management and ensure software continues functioning properly even as platforms are updated.

Additionally, Experion R400 extends the availability of op-erating systems and key infrastructure components to help prevent them from becoming outdated or obsolete.

The system also features a new Profibus Gateway that pro-vides redundancy, further improving the reliability of critical process control applications such as intelligent motor control centres and remote critical equipment monitoring.

www.honeywell.co.za

Lubrication for power station fansThe OMSA Group has supplied OMSA Lubrication Systems for the primary air (PA) fans and forced draught (FD) fans at two new local power stations based in Mpumalanga (Kusile Power Station) and Limpopo (Medupi Power Station).

The OMSA Group has supplied OMSA Lubrication Systems at two new local power stations

The lubrication systems are to lubricate the fan and motor bearings plus hydraulic actuation of the FD fans, and have been built to customer specifications unique to these two power stations and the OEM. The fans have been supplied by Howden Power.

OMSA will be providing the technical back-up to these power station fan lu-brication systems as well as providing on-site training and an audit of service and maintenance requirements.

Xen Papastamopoulos, OMSA, Tel: (011) 793 5562, Email: [email protected]


Expansion of Johannesburg gas networkReatile Energy has acquired a 25% shareholding in Egoli Gas, the transaction will see Reatile Energy represented with 2 seats on the Egoli Gas board. This deal signals develop-ments in the natural gas sector in the greater Johannesburg metropolitan area.

“Reatile will extend its business to leverage opportunities in the natural gas market, while Egoli Gas will focus on building its corporate customer base with our existing customers,” says Simphiwe Mehlomakulu, chairman of Reatile Energy.

Bheki Vilakazi, managing director of Egoli Gas, points out that the rationale behind partnering with Reatile Energy is due to its technical background in the energy sector, especially since the company has close ties with established gas and energy industry players.

Bheki explains, “Natural gas will mainly be used for heating and cooling applications, thus there will then be more choice available to customers, and less reliance on electricity as a sole source of supply for power needs.”

Simphiwe notes that as the cost of electricity increases and so to does its unreliability, many businesses could benefit from the use of gas as a power alternative. “Gas is available 24/7/365 and is more cost-effective,” he says.

Reatile Energy has acquired a 25% shareholding in Egoli Gas which signals developments in the natural gas sector in Johannesburg

Reatile and Egoli Gas have identified key growth areas, targeting sectors such as financial institutions, tele-communications companies, public and private healthcare facilities, to name a few.

“We are also looking to supply gas to companies in the central business district of Johannesburg and to expand the existing network into new areas like Sandton,” continues Simphiwe.

Simphiwe and Bheki both agree that the biggest hurdle they currently face in expanding the gas network is the consumer’s lack of knowledge about the availability and benefits of gas.

“In the near future we hope to offer tri-generation to customers, meaning that in addition to heating and cooling applications, they will use our gas for electricity,” concludes Simphiwe.

Simphiwe Methlomakulu, Reatile Gaz, Tel: (011) 514-0587, Email: [email protected], Bheki Vilakazi, Egoli Gas, (011) 356-5000, Email: [email protected]

POWER GENERATION NEWS

FORTHCOMING FEATURESAugust

Power TransmissionPipes, Pumps and ValvesComputers in EngineeringFilters and Filtration

SeptemberWelding and NDTOils and LubricationCompressors, Air motors and Vacuum pumpsVessels, Heat exchangers, Tanks and containers

Contact Pauline Bouwer on Tel: (011) 781-1401, Fax: (011) 781-1403 or Email:[email protected] for

details

••••

••••


LETTER TO THE EDITOR

you! This new section is timely and promises to be very informative. Do you have plans to do a similar article on PV (photo voltaics)?

By the end of 2009, the relative installed capacities of CSP and PV worldwide were 4 GW vs 21 GW.

While the initial costs are higher at present ($2,5 - $4,0/W for CSP vs $5,5 - 6,5/W), PV has the

big advantage that capital costs are declining and its running and maintenance costs are very, very low, if not negligible.

Simply, there aren’t any steam generators, turbines, alternators, condensers etc, that all require operating and maintenance on an ongoing basis.

Another big advantage for PV is that you do not require a large organisation such as a utility to own and run a PV plant! With feed-in technology and the principle of small suppliers sell-ing power (at subsidised rates) back into the grid in daylight hours now well developed, every Tom, Dick and Harry can become a power supplier using PV as is already happening in Europe, the USA and many countries in Asia. Large scale, utility owned PV generation plants are of course also possible.

ParityPV is no longer constrained by the cost and availability of silicon based, crystalline cells. Rapid progress is being made with the so-called thin film technologies. In 2000, thin film technology represented less than 1% of worldwide installed PV capacity; by 2009 this had grown to 12% and it is forecast that by 2020 it will be 40%! While they are not yet as efficient as crystalline units, efficiencies are improving and panel costs are declining and the expectation is that long term costs will reach parity with conventionally generated power.

Hennie du Preez, director, Leobeck Sales International (Pty) Ltd.

Every Tom, Dick and Harry

Every Tom, Dick and Harry can become a power supplier using PV as is already happening in Europe, the USA and many countries in Asia

Dear Editor,I missed the March issue and the first article in your new section on Power Generation, but was delighted to read the CSP article in the April issue - thank


NUCLEAR INSTITUTE (SA BRANCH)

In reading up the Korean nuclear program I kept coming across references to a reactor called SMART, System-integrated Modular Advanced Reactor. This is a home-grown 330 MWt system

being developed by the Koreans to supply a devel-oping market they perceive for small reactors both

to power small and deregulated national grids and for process heat applications. Reading the literature is saddening in that it’s full of phrases we used to use to promote the late lamented PBMR.

Failure to attract overseas investment and the subsequent withdrawal of Government funding led to the collapse of the PBMR. An obvious question is therefore – who is funding SMART? The answer is not entirely clear. What is clear (World Nuclear News) is that a 13-organisation consortium led by KEPCO, designer, builder and operator

Small to MediumLast month I held forth about the astonishing development in South Korea, specifically about their nuclear en-deavours since the Korean war some sixty years ago. Seoul evidently changed hands several times during the war and now, having seen photographs of the devastation, I’m even more amazed. One thinks of the ‘German

miracle’ after 1945. Widespread destruction every now and then is evidently salutary.

of Korean nuclear plants, has put up US$83 mil-lion ‘to complete design work’. The project is led by the Korean Atomic Energy Research Institute (KAERI) together with other organisations including Doosan Heavy Industries which are presumably also contributing. Government has chipped in a further $58 million. About three hundred ‘researchers and engineers’ are employed on the project.

Think anewAn early boost for the PBMR came in 1997 with a study by MIT. Students were asked to think anew about the optimum type of reactor for the future. They concluded that a 200 MWt graphite moder-ated, helium-cooled system was the one to go for. This led indirectly to the early participation of the American utility Exelon in the PBMR project. Interest in SMRs, small to medium reactors, was growing. Work on SMART started in 1996.

Indeed, there were in the 1990s quite a number of SMRs in the nuclear news. Names like SIR, PRISM and PIUS spring to mind. SIR (Rolls-Royce involvement) stood for Safe Integral Reactor, PRISM (General Electric) for Power Reactor Inherently Safe Module (!) and PIUS (ASEA-Atom) for Process Inherent Ultimate Safety. Designers had realised that small was safe. The bane of fission product residual heating that melted the TMI core could be removed from low power reactor cores by passive, gravity-driven cooling systems, passive in the sense that they contain no active components, pumps and valves and so on. This claim is also made for SMART. Natural circulation removes the heat.

Rationalise the sceneIn 2000, the Generation IV International Forum (GIF) was established to rationalise the scene and to select for international co-operation a few of the more promising systems. Safety was of course to be a major consideration as were fuel efficiency, in other words the ability to breed more fuel, waste minimisation and weapons proliferation resistance. Six systems including the Very High Temperature Reactor (VHTR), basically the PBMR, were selected

The GIF effort at rationalisation may not have worked. Astonishingly, according to Korean data, ‘over fifty concepts and designs of innovative SMRs

Designers had realised that small was safe

John Walmsley

The Korean’s Smart reactor


are under development worldwide’, some ready for commercialisation. Evidently the US DOE forecasts a power generation and process heat market for 500 to 1000 small reactor units by 2050. ‘Twenty of fifty-four countries planning to construct nuclear power plants for the first time will have to build small nuclear reactors with a capacity of less than

Over fifty concepts and designs of innovative SMRs are under development worldwide

300 MWe’. Currently, just thirty-one countries operate power reactors.

The Koreans claim that one 330 MWt SMART reactor will provide the necessary 90 MWe of power and sufficient desalinated water for a city of 100 000 people. Maybe the long awaited nuclear renaissance will creep in through the back door.

Surely not possible?So what does it look like, this SMART reactor? Es-

sentially it’s a small pressurised water reactor but with the entire primary circuit inside the pressure vessel. That includes the reactor core, steam generators and the pressuriser. Control is by control rods entering via the top dome, by burnable poison in the fuel to flatten the flux and by boron in the primary circuit water. Much mention is made of the passive residual heat removal system and other ‘advanced safety features’.

If a city is to be powered by several such small reactors extensive emergency evacua-tion planning around each one will surely not be possible. The Korean licensing authority is expected to pronounce on safety issues and approve the plant by the end of 2011.

John WalmsleyYong-gwang Nuclear power station, South Korea

NUCLEAR INSTITUTE (SA BRANCH)


A lthough compressed air is a well-tried system, it has certain drawbacks. Firstly, it is expen-sive to produce, and with the rapidly rising

price of electricity, is becoming more so. Secondly, because of the length of many mines compressed air piping systems, much of the pressure is lost because of air leaks.

Another factor bearing on the use of compressed air is the introduction in some deep level mines of electrically-driven rock drills. These may reduce or entirely phase out the use of compressed air in mines. For example, to save costs, at AngloGold Ashanti’s Tautona mine, which is being deepened, the deeper extension will not be supplied with compressed air.

AdaptionWith these developments in mind, Ernest Lowe, the hydraulics and pneumatics engineering solutions

company, adapted one of its pneumatic actuator cylinders so that it would operate on water pressure instead of air pressure, using the existing water column pressure as an energy source.

Among others, this Aqua-Hydro system offers two massive advantages: improvement on safety and potential cost savings.

SafetyThe Aqua-Hydro system has a valve, which controls the actuator cylinder. The valve works as a ‘dead mans’ controller. If the operator releases the valve, it automatically moves the water cylinder actuator into the closed position. Should a box-front operator see that there is a risk of a mudrush, he can instantly abandon the control valve and run to safety, knowing that the box front will close automatically.

Other safety aspects concern that health of the op-erator. Compressed air exhausting from pneumatic equipment tends to be noisy, whereas the water-operated equivalents are almost silent. As water is not compressible, the control of the box front is more positive and consequently safer.

Use of airThe largest cost savings brought about by the instal-lation of the Aqua-Hydro system is to be found in the reduction in the use of increasingly-expensive compressed air.

Box fronts are often far from the shaft station and even further from the surface air compressor. As neglect and air leaks reduce the pressure, in the working areas, what little remains has to be shared between the various compressed-air driven equipment.

Water problemsAs water leaks are visible, and as mines try to limit the amount of water they have to pump to surface, these leaks are usually repaired immediately. As box fronts are, literally and figuratively, at the bottom of the production hierarchy, they are often not able to load at times when the rock drills have the first call on compressed air.

In most mines, there is naturally occurring water as well as used service water. This has to be pumped out of the mine and stored on surface in dams. This water has to be piped back underground for use in rock drills, and for dust control among other applications. The depth of the pipes down the mine shaft ensures the water has ‘head’ of pressure, which is a source of free energy for equipment in the mine. The Aqua-Hydro actuator cylinder uses this free energy for its operation.

Cost savingsAn engineer at Tautona worked out the possible

For the past 100 years, mines the world over have used com-pressed air as a power source to drive equipment such as rock

drills and cleaning jets.

Water Works Deep Down

Adapted one of its pneumatic actuator cylinders so that it would operate on water pressure

HYDRAULICS & PNEUMATICS

�0 THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010

cost reduction that the Aqua-Hydro cylinders could bring about. Based on replacing 60 pneumatic units in a year with Aqua-Hydro systems, the engineer estimated that costs of more than R500 000 a year could be saved.

However, it has been pointed out that if one considers the com-pressibility of the air, compared to the non-compressibility of the water, it is possible to multiply the first figure by five. If one takes factors such as improved operational efficiency and extended maintenance intervals, the savings could potentially grow a further ten times.

Additional benefitsWhile the water Aqua Hydro cylinder is heavier and more costly than its pneumatic counterpart, its operation is essentially for free. This reduces the cost of ownership of the water cylinder to a fraction of the cost of the pneumatic equivalent. In a deep level gold mine there are hundreds of box

fronts, the potential for savings is colossal.

Even though the Aqua-Hydro system was designed for controlling box-fronts, it can be adapted to any number of applications. It is possible to replace

any pneumatic cylinder with water cylinder provid-

ing there is enough flow and pressure.

Will cope under pressureThese units have shown to work under

various pressures ranges, from a minimum of about four bar, to a maximum of close to

32 bar. In contrast, the pneumatic cylinder operates in a range of 4.5 to 10 bar air pressure.

To generate enough pressure to operate an Aqua-Hydro system, the mine needs to be at least 50 metres deep. Most South African mines are con-siderably deeper than this.

The system will not be affected by electrical power failures. Also, water, unlike hydraulic fluid, when spilled, poses no environmental threat.

No pipes neededWhat makes these water cylinders an even more attractive cost-saving proposition is that they do not need any special piping to be installed in the haulages. In most haulages, there are service-water pipes that take water to the workface.

The water in these pipes is under sufficient pressure to operate Aqua-Hydro water-powered cylinders. These pipes run past the box fronts, so tapping into the main water line for a feed to the water cylinder is simplicity itself.

Comes with filtersIn terms of water quality, water supplied to the rock drills is drawn from a dam on the surface. Before it goes underground, it is filtered and particulate matter and alkalinity levels are monitored to avoid damage to pipes and machinery.

If the acidity in a mine’s water is high, the inside of the cylinder can be made from stainless steel or glass fibre. The Aqua-Hydro control valve is also fitted with a strainer to prevent any stray particles, such as rust from the pipes, entering the valving or the actuator cylinder.

Control panelThe control panel is equipped with a standard Ernest Lowe slide valve capable of operating up to 30 bar pressure. The control panel has two lockout systems to fully isolate the system. These allow for locking the cylinder in either fully extended or fully retracted position.

Manny Vieira, Ernest Lowe, Tel: (011) 898 6600, E-mail: [email protected]

Run to safety, knowing that the box front will close automatically


THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010 �1

“SA Mechanical Engineer” speaks to Norman Hall, the president of SAFPA (South African Fluid Power Association), about a new system that will in future provide end-users with the

assurance that they’re getting the right stuff.

“All hose assembly practices must conform to the manufacturer’s recommendations and the practice of ‘mix and match’ is unacceptable,” he says. “Components for a hose assembly must be com-patible by design, size, type and manufacture and must have compatibility proved by testing to the appropriate specification. The mixing of inserts and ferrules from different or unknown manufacturers, or the use of unmatched hose and end couplings is potentially dangerous and hence unacceptable. The use of unbranded or unmarked hose or the reworking of used hose is also potentially danger-ous and is unacceptable.”

The new ActWith the new South African consumer protection act, set to become law by October this year, suppliers of

Controls on the WayIn hydraulic and pneumatic applications, proper hose assem-bly is vital, not only in terms of the effective operation of ma-chinery, but also as far as safety is concerned. Hose assembly guidelines are usually specified by the OEM of the equipment, but even if they aren’t, it’s crucial that the application and the type of fluid used is considered when a replacement hose is

made up.

hose assemblies will be held responsible for unsafe or poor quality products. In terms of Section 61 of the act, a producer, importer, distributor or retailer of goods is liable to a consumer on a no-fault basis for harm, including death, injury, physical damage or associated economic loss, which is caused by unsafe or defective goods.

“This means that the suppliers will be responsible for the safety of their hose assemblies released to the market,” says Norman. “SAFPA is helping both the supplier and the end-user to formulate a hose accreditation scheme for all those assembly shops which care to comply with the law. We have the capability now to audit the assembly shop regard-ing its purchase, manufacture and sale of items in terms of traceability. Each audited shop will receive a certificate stating that it’s a SAFPA-approved assembly shop.

“We based our accreditation system on the British fluid power association’s system,” says Norman. “It’s now up to each shop to join SAFPA and get accredited. We’re about to audit the first hose as-sembly shop and hopefully the others will follow soon. It’s in their own interest as end-users will soon start asking for this accreditation to counter some of the bad practices out there. The SAFPA accreditation scheme will not only improve the standards in industry in general, but it will reduce manufacturer liability and raise supplier quality levels in the market.”

Tax relief on hosing As South Africa does not have its own hydraulic hose manufacturers, all the main specialised wire reinforced hosing for hydraulic applications is im-ported. “Another project SAFPA has now finalised is getting rid of import tariffs on imported hydraulic hosing,” says Norman. “It has taken eighteen months because it meant dealing with customs and various other departments to do away completely with tax on imported hose. This will be a gradual process while the importers of hose are now depleting old stock and then the price of hydraulic hose should come down in the next couple of months.”

Norman Hall, President of SAFPA, Tel: (011) 888-7163, E-mail: [email protected], SAFPA web site: www.safpa.org.za

Norman Hall, President of SAFPA

The practice of ‘mix and match’ is unacceptable


THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010 ��

E llis Park stadium in Johannesburg, however, no longer has this problem. An infrared heating system has been fitted to raise the comfort level for spectators in the grandstand

areas. This radiant heating system was installed by Eastleigh, a combustion engineering specialist company in Benoni who are the sole agents for GoGaS heating products from Germany. “SA Me-chanical Engineer” speaks to Fritz von Graszouw about this new technology.

Thermic comfort“Due to the high efficiency rate of infrared systems, a high level of thermal comfort is achieved, even at low outdoor temperatures,” Fritz elaborates.

“The effect can be compared with solar radiation in winter where even in low temperatures, you feel comfortable.

“Our high efficiency radiators emit infrared radia-tion which transforms into heat once it hits a solid surface. As spectators are in the stadium only for a

short stay, the heat must be available at once which is exactly what this system does. Instant heat, just like when a light is switched on.”

FuelsEllis Park utilises natural gas from the Egoli gas line, but the system can also be run off gas bottles. “In the not too distant future, it will also be possible to run off natural gas from a virtual gas pipeline supply system where gas is stored in large special containers called Mats,” says Fritz.

Mats are currently being introduced to the South African market systematically for a variety of applica-tions, including vehicles that have been converted to run on compressed natural gas.

Operation“The system is switched on remotely simply by flicking an electric switch,” says Fritz. “The tem-

Turning Up the HeatFans of winter sports like rugby and soccer know they have to brave the cold to see their favourite teams play, but even sea-soned fans sometimes have second thoughts when the weath-er turns really nasty. This is compounded by the fact that the new stadia are all open structures, putting more of a bite in

the cold air flowing into the grandstands.

The GoGas infrared radiant heater emits medium-wave infrared radiation transferred into heat when it hits a body

HEATING & COOLING

Instant heat, just like when a light is switched on

�� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010

HEATING & COOLING

The Ellis Park installation

perature is controlled by a sensor aimed at the actual flame and it will adjust the flame lower or higher to radiate a constant pre-set temperature. The gas burner is fitted with a pilot burner ignition device and detection system as opposed to the standard system usually used on gas burners. It is also fitted with a unique new anti-propagation device that not only simplifies installation, but also prevents propagation from damaging the burner while increasing the safety of the system.”

A heating system using gas infrared radiant heaters is the best way to fulfil the special requirements of open space heating. It is clean and easy to regulate, there are no distribution losses and it’s energy-sav-ing as heat is immediately usable.

Comfortable and healthyThe gas infrared radiant heater emits medium-wave infrared radiation transferred into heat when it hits a body. As the air is almost permeable to radia-tion, it is not heated up. Therefore it is possible to heat open grandstands in sports arenas or other open spaces economically and comfortably. Bright radiators are directly heated. The gas/air mixture burns on the surface of a ceramic plate where the surface temperature is about 850°C to 900°C. Most of the heat is transferred to the surroundings by direct radiation.

The temperature sensed by a person is a combination of the air temperature and the intensity of radiation. Due to the high amount of radiant heat emitted by the gas infrared heaters, a high thermal comfort is reached even in case of low outside temperatures. The ambient air remains cool and fresh and thus the climate is comfortable and healthy. In addition, indirect heating comes from the heated walls, floors and other objects warmed up by the radiation before spectators are seated.

ImpressedPaul Appalsamy, Chief Executive Officer at Ellis Park comments, “Often event schedules overlap with our winter and any event with a 15h00 kick-off and later, held at the stadium during the winter period, is very uncomfortable. Blankets are provided to our VVIP and VIP guests to ensure their comfort but it’s cumbersome and untidy. Fritz Van Graszouw of Eastleigh Combustion Engineering

Less of a crush with everyone bundling into their boxes


“When we were first exposed to the GoGaS heating concept, I was immediately convinced that such an installation would be of definite value to our venue and in line with our facility improvement. The GoGaS space heating covers the main west grand stand over level 1 to 3.

Bundling into their boxes“And it’s a real big hit with the ladies who are now able to sit and enjoy the total atmosphere of the game,” he continues. “It also means we have less of a crush with everyone bundling into their boxes because of the cold. The installation process and the speed with which it was implemented was also very impressive, the suppliers are leading experts in this industry.”

The GoGaS heating system, installed at outdoor and indoor sports arenas all over Europe is, however, not only for stadia heating. “We customise the control system for various applications including factories, churches and large aircraft hangars,” says Fritz. “In industrial applications, the system is used for any drying operations as you’d find in paper, textile, steel, aluminium, plastics, ceramics, fibre cement, food and other industrial applications.”

Fritz Von Graszouw, Eastleigh Engineering, Tel: (011) 969-1992, Email: [email protected]

The GoGaS heating system, installed at outdoor and indoor sports arenas all over Europe is not only for stadia heating

The control unit, activated remotely

HEATING & COOLING

Various applications including factories, churches and large aircraft hangars


Typically contractors now come to us saying they’ve got a maximum of X amperes to run the plant and we’ll guide them on the selec-

tion of the best possible systems within the given parameters,” Robert Hanssen, director of Cubicool

International tells “SA Mechanical Engineer” when we sit down to talk about energy saving machin-ery.

In the chain of events leading up to a mechanical installation all the players along the line tend to over-specify equip-ment to make sure it functions to the approxi-mated require-ments. This often results in extra

Keep Your CoolToday new cold storage facilities, supermarkets and com-

mercial complexes are allocated a certain quota of power to run the complete facility and this may not be exceeded. This requires very careful planning in terms of specifying the size and type of refrigeration and airconditioning plant for a par-

ticular site’s power allocation.

costs, not only in terms of ending up with bigger machines that cost more, but also in their energy consumption, especially in the case of refrigeration and airconditioning installations.

“There are a number of factors that influence an installation, but generally we all tend to over-design and that’s mainly due to a lack of information,” says Robert. “Although it’s prudent to design ac-cording to the highest load the customer specifies, everyone seems to build in a safety factor along the design chain”.

Exact numbers“A client may, for example, very rarely store two tonnes of produce in his refrigerated cold room. To be safe he specifies two tonnes and then the contractor or engineer adds another half tonne just to make sure he’s also playing it safe,” explains Robert. “This sort of information is not at the level yet where we as a supplier can accurately design a system specifically for optimal energy efficiency. However, there are a number of players in the market who come to us with the exact numbers in terms of capacity requirements and we can then closely match the design to requirements.

“Furthermore, in areas prone to fluctuations in power supply for instance, you’d typically need special protection to protect the refrigeration equip-ment as well.”

Last minuteCubicool systems are modular and avail-able in either indoor or outdoor units that are built up according to requirements. “We tend to find that the consideration of the refrigeration plant is often left to the last minute. Then they realise that there’s not enough space allocated inside the building to accommodate the plant,” says Robert. “Being modular and easy to configure in multiple stackable com-binations, our systems are particularly suitable in situations like this.”

To broaden the choice further, units can be supplied in various styles. The open style condensing base unit is for the DIY refrigeration engineer while the fully assembled indoor Platinum Line range or weatherproof outdoor Cubipack units have additional components fitted into the unit according to the requirements of each specific application, including

Robert Hanssen, director Cubicool International

The Cubicool Mulitiplex system

HEATING & COOLING

All the players along the line tend to over-specify equipment to make sure


an integrated electrical panel and controls. Control of the unit is also possible from a remote control panel.

In tandemA tandem hermetic compressor system (developed by French manufacturers Tecumseh and introduced by Cubicool) is a local first, with two compressors used in parallel and controlled by an electronic compressor management system for optimum efficiency.

“We recognised the advantages of using two smaller compressors in tandem rather than using one large compressor,” says Robert. “This enables starting up sequentially which lowers the start-up current considerably. It can also be used to match the load by switching one compressor off when the temperature or load is reached and then main-taining this level with only one compressor. This naturally also reduces the general noise level and this design has proved to be very successful in the South African market.”

Multiplex systemsThe Cubiplex is a compact concept in which the refrigeration unit is fitted with semi-hermetic com-pressors in a 2, 3 or 4 compressor configuration. These units are available in an indoor or outdoor version. The outdoor systems are fully weatherproof,

with standard Cubicool specification claddings and roof and built within corrosion-resistant frames.

“Typically these units are supplied complete with integrated condensers fitted inside, which is not normally the case,” says Robert. “We’re the first SA manufacturer to market a fully integrated air-cooled multiplex refrigeration unit. Traditionally the condensers are situated remotely, but our clients see a benefit in installing a completely integrated, factory tested unit, especially in more remote locations.”

Robert’s final thought on refrigeration: “I can’t emphasise enough that all parties involved should share information to reap the benefits of an ef-ficiently running plant.”

Robert Hanssen, Cubicool International, Tel: (011) 974-6541, Email: [email protected]

HEATING & COOLING

Using two smaller compressors in tandem rather than using one large compressor

Log onto www.promech.co.za to read back issues of

“SA Mechanical Engineer”

Energy-saving, superior lubricants for supreme performing refrigeration equipmentEngen offers a range of Mobil synthetic and mineral oil-based refrigeration oils: Mobil Gargoyle Arctic, Mobil EAL Arctic, MobilGargoyle Arctic SHC and Mobil Zerice S. These oils help to enable an effi cient and reliable operation, so whatever your refrigeration application, we have a lubricant suitable for your needs. Formore information, call the Engen Customer Service Centreon 08600 36436 or visit www.engen.co.za orwww.mobilindustrial.com

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Annual Dinner 2010

Engen Table

SAIT President, John Fitton, welcomed everyone; Grace was said by Johan de Koker, and Anton Allner proposed the Toast to the SAIT.

David Collins was the after-dinner speaker. Dave consults on climate change response and energy strategies to many top companies, the SA coal industry and to various industry organisations. He has recently participated in several radio and TV shows. His fascinating, though somewhat alarming presentation on the looming crisis of civilization as driven by climate change, the end of cheap fossil fuels and population growth was much appreciated.

The Annual SAIT Awards:John Fitton presented the SAIT Student Award to Kgaugelo Mokhwazo of the University of Pretoria for her Undergraduate Final Year Research Project in B.Eng Chemical Engineering: “Effect of Biodie-sel Addition on the Lubricity of Petroleum Based Diesel.”

A warm welcome of gentle popular tunes by Isabel Bradley on flute

Guest Speaker Dave Collins and his wife Gisela

John Fitton presented the SAIT Student Award to Kgaugelo Mokhwazo

This year’s Annual Dinner and Awards Evening was held at the Wanderer’s Club in Illovo on Friday evening, 30 April. Each of the sixty SAIT members and guests who attended this gala event enjoyed themselves

enormously, not least the marvelous Wanderers buffet meal, and the wines, flowers and menus sponsored by Engen.

SAIT


We were honoured to have Dr Louw Alberts, Patron of the SAIT attend the Dinner, and present the Louw Alberts Award to George Peratides, “in recognition of his ongoing support of the SAIT through lectur-ing and administration in the training programme, and as a mentor, giving willingly of his time and expertise in enthusiastically passing knowledge and experience on to the next generation”.

John Fitton presenting the Best Technical Achievement Award to Gerald Leibstein of Engen

John Fitton, Dr Louw Alberts and George Peratides with the Louw Alberts Award

The final award of the evening went to SAIT Secretary, Gill Fuller, Secretary of the SAIT for 21 years!

Professor Philip & Mrs Corné de Vaal

The Best Technical Presentation went to Warren Walker of SKF Bearings for his presentation, ”Opti-mising Energy Efficiency within Rolling Bearings”, given at the Technical Meeting on 29 September 2009. Warren was unfortunately not present.

Gerald Leibstein of Engen Petroleum Ltd, was awarded the SAIT Best Technical Achievement Award for his work on “Electric Energy Savings by using Synthetic Oil instead of Mineral Oil”.

The 2010 Annual Dinner was a great success, thoroughly enjoyed by all.

G Fuller, SAIT Secretary, Email: [email protected]

SAIT

Engineer PlacementsProfessional opportunitiesOur job board continues to display a wide variety of excellent job positions that you can review and apply for on- line. Keep your credentials on our secure and confidential database, update them at any time.We keep in touch with you.www.engineerplacements.com


Market Forum

Larger incinerator for medical wasteAi-Tec has completed the design and manufacture of a new large capacity medical waste incinerator.

“The Macroburn VMED 500C incinerator has been developed by Ai-Tec in response to the urgent need for safe incineration of medical waste, with no harmful effects on the environ-ment,” says Arnold Retief, a director of Macrotec, Ai-Tec’s manufacturing operation. “The increase of illegal dumping of medical waste and non-compliant incineration, have become global problems,” he adds.

This new incinerator has the capacity to handle approxi-mately 4 845 kg of mixed medical waste per day, without any smoke or toxic emissions.

This Macroburn incinerator achieves complete burnout within the incinerator itself, thereby maintaining emissions well within EU (European Union) and DEAT (Department of Environmental Affairs and Tourism) standards.

An important feature of this new incinerator is its economical operating system, which is highly efficient compared with traditional wet scrubbing systems. Conventional incinerators require large quantities of water that need to be treated for contamination prior to release.

Hendrik Haywood, Nkosinathi Nkwanyana or Arnold Retief,Advanced Industrial Technology (Ai-Tec), Tel: (032) 552-2658, Email:[email protected], www.ai-tec.co.za

Ai-Tec has completed the design and manufacture of a new VMED 500C medical waste incinerator

The ultimate on-site solutionAtlas Copco’s nitrogen generators match industry demand for continuous availability of pure nitrogen, eliminating potentially hazardous handling of high pressure gas cylin-ders. “Our NG range provides on-site nitrogen generation in harsh and demanding working environments,” says Philip Herselman, Atlas Copco business line manager, Industrial Air Division.

The units supply the exact nitrogen purity demanded by any application, providing uninterrupted operation for a diverse range of applications. Furthermore, the nitrogen generators offer continuous surveillance which Philip says is essential for maximum production time. “In addition, the system’s monitor-ing ensures reduced maintenance and energy consumption.” All units feature an electronic control panel with an oxy-gen indicator and alarm, pu-rity indicator as well as an output pressure and alarm, ca-pable of con-trolling up to three towers.

“The ent i re range of NG generators fea-ture automatic request fo r maintenance on generator componen ts which leads to minimal down time due to unplanned stoppages and breakages,” he concludes.

Philip Herselman, Atlas Copco, (011) 821-9110, Email: [email protected]

New nitrogen generators

Energy efficiency second to noneElectric motors are the highest consumers of energy, a fast dwindling commodity that is becoming alarmingly expensive. With ever stricter legislation on reducing energy consumption and CO2 emissions, there is an increasing trend for industries to change to energy efficient electric motors.

The new ABS EffeX range of submersible pumps is fully compliant with the IE3 premium-efficiency standard.

The EffeX range incorporates the IE3 motor designed and is tested in accordance with IEC60034-30. According to ABS general manager, Hennie Basson, “The range’s design technology includes greater safety margins and ensures that the pumps meet current stringent requirements and exceed planned legislation.

Market Forum

Promech Publishing has a BEE rating of 97.2%


Compact heat exchange solutionSpirax Sarco’s EasiHeat is a compact heat exchange solution when compared to tradi-tional shell and tube options, with the core unit occupying only 1,2 m³.

EasiHeat can be used with either electric or pneumatic actuated control valves, and its steam plate heat exchanger can operate partially flooded.

The design of EasiHeat typically eliminates the EasiHeat can be used with either electric or pneumatic actuated control valves

In addition, the built-in IE3 premium-efficiency motors offer the advantage of lower operating temperatures (NEMA Class A) and reduce the need for cooling.

“Because the temperature rise is so low, continuous opera-tion of smaller motors (ABS PE1 & PE2 pumps) for dry well applications without the need for cooling is also possible.

This also leads to a considerable improvement of the bearing environment and reduced load on the stator. “The ABS EffeX range includes ABS’s Contrablock Plus impeller design with adjustable bottom plate to ensure dependability throughout the pump lifetime. Larger pumps also use optimised closed impeller designs to give the best balance between reliability and energy consumption,” concludes Hennie.

Hennie Basson , ABS Wastewater Technology, Tel: (011) 397 1612, Fax: +27 (0)11 397 1795, E-mail: [email protected]

New range of V-beltsBearing Man Group (BMG’s) Fenner branded power trans-mission components has been extended to include a new range of V-belts.

“The new range of NuTLink V-belts for classical V-section drives and SuperTLink detachable belts for wedge drives, is manufactured from a polyester/polyurethane,” says Lee Quigley, general manager of drive belts, BMG.

“The link construction of this new series enables belts to be fitted quickly and easily, even on inaccessible drives. The flexible design means belts can be joined around the shafts, without having to dismantle the drive,” she adds.

need for a storage or buffer tank, which saves footprint space and unit weight. Having no storage or buffer tank eradicates a potential breeding place for legionella or other bacteria and dispenses with the need for regular inspections.

EasiHeat can operate at low or even sub-atmospheric tem-peratures to minimise the risk of scaling in areas where it is prevalent. The basic unit contains the matched key components that will affect the control of the system. If required, various options can then be added to this basic design to provide extra safety features and steam quality improvements.

Because of the high maximum operating pressure and tem-perature limits of the components used in EasiHeat, extra pressure reducing valve stations and safety valves are not required.

Emily Heath, Spirax Sarco, Tel: (011) 230-1300, Fax: (011) 393-1922, E-mail: [email protected], www.spiraxsarco.com/za

The ABS EffeX range of submersible pumps

Market Forum


Component production doubledFesto has supplied three loading and handling solutions to SMA Engineering in East London which are being used in the manufacture of components for air conditioning units used in German cars.

The implemented solution is being used to load and unload components into a forming machine and includes an FEC-30 programmable logic controller (PLC) and expansion unit, rodless cylinders, rotary drives, cylinders with FEN guides, solenoid valves, sensors and accessories.

Prior to the installation of the handling solution, SMA Engi-neering employees conducted this procedure manually. Neville Schwulst of Festo says, “Festo HGR grippers are attached to rotary drive cylinders, which allow the system to pick and place the components into a forming machine. Once this procedure is completed, it is then reversed to facilitate the forming of the opposite side of the component, thereby eliminating human error.

Joanne Dexter, Festo, Tel: (011) 971-5560, Email: [email protected]

The Festo handling system is used to load and unload components into a forming machine

Geared for great customer service Hytec offers original equipment manufacturers (OEMs) peace of mind with a mobile gearbox repair facility that complies with manufacturer standards. “We offer the repair facility to our customers as part of our commitment to quality service. OEMs who use this facility are assured of superior workman-ship,” explains Hytec’s André Lindeque.

Although the actual repair of a gearbox is not a lengthy process, the availability of spares and the waiting period to acquire stock impact heavily on the period it takes to deliver a repaired gearbox to its owner. In some cases, this can take up to a year. Hytec remanufactures the gearbox completely, no chroming or welding of old parts are done. In addition, inspection of all parts for hairline cracks is part of the service.

The repairs can be carried out either on-site, especially in the case of very large or heavy gearboxes, or at Hytec’s facility in Johannesburg.

Hytec technicians have access to Bosch Rexroth documen-tation via the Internet, and they receive on-the-job training from German experts when needed. Representatives of Hytec also pay regular visits to gearbox manufacturers overseas to stay abreast of any new developments in this field.

André Lindeque, Hytec, Tel: (011) 975-9700, Email: [email protected]

Hytec technicians have access to Bosch Rexroth documentation via the Internet

Slurry pump gets upgradedWeir Minerals Africa has launched its upgrade of the Warman AH design, heavy duty slurry pump.

“The original design is in excess of 50 years old,” explains Rui Gomes, product manager for slurry pumps at Weir Minerals Africa.

By eliminating the need for an externally flushed gland, dilution of the product is eradicated. “The improved seal-

NuTLink V-belts are available in all the main industry belt profiles – Z/10, A/13, B/17 and C/22. SuperTLink detachable wedge belts are available in SPZ, SPA and SPB sections to enhance performance of wedge belt drives.

Lee Quigley, BMG, Tel: (031) 576 6200, Email: [email protected], Web: www.bmgworld.net

Market Forum

Log onto www.promech.co.za to read back issues of “SA Mechanical Engineer”


Market Forum

A new force on the global stageMcNally Bharat Engineering Company has purchased Humboldt Wedag Coal and Minerals Technology and its subsidiaries in South Africa, India, Russia, China, Australia and Brazil as well as the engineering workshops in Cologne, Germany.

The new company, MBE Coal & Minerals Technology will have its headquarters in Cologne, Germany. In South Africa, it will be known as MBE Minerals SA.

MBE in India has been providing turnkey solutions in the power, steel, coal and mining, ports, aluminium, materials handling and mineral processing industries since the early 1960s.

In South Africa, the new MBE Minerals SA brings to the table its capability to design, engineer, supply equipment, and provide process solutions.

Johannes Kottmann, MBE Minerals, Tel: (011) 397 4660, www.humboldtwedag.co.za

A diagram illustrating the Warman AH pump upgradefeatures

Challenging industry normsA modification of a drill rig by High Power Equipment (HPE) Africa has provided drilling company De Wet & Seun Boorkontrakteurs with an increase in drilling production and turnaround times.

HPE Africa’s involvement in the modification of a drill rig ex-cavator for drilling company De Wet & Seun Boorkontrakteurs will allow the company to increase its drilling production by up to 35% per month. De Wet & Seun Boorkontrakteurs managing director, Kobus De Wet says that for every 1 metre

that a regular drill rig drills, the modified Hyundai machine is capable of drilling 35% more.

In addition to saving time, the modified drill rig offers certain safety aspects. “When drilling on the crest of a rock face, the modified drill rig’s boom operates up to four metres away from the actual excavator, allowing a safe distance of approximately 6 metres between the actual drilling activity and the operator of the machine,” says Kobus.

In a traditional drill rig set-up, the operator’s seat would be positioned much closer to the actual drilling site, thereby creating an unnecessary safety risk for the machine operator.

HPE Africa sales consultant Peter van Rensburg explains that the excavator drill can be used in any application that requires

drilling for the purpose of blasting.

Peter Van Rensburg, HPE Africa, Tel: (011) 397-4670, Email: [email protected]

ing capability minimises or completely eliminates leakage of actual product and in many cases chemicals or other expensive solutions,“ he says.

The second phase of the Warman AH pump upgrade involves the impeller and matching throat bush design. The modi-fied impeller vane profiles provide the same performance at the same speed as previous models, but with increased wear life.

Rene Calitz, Weir Minerals Africa, Tel: (011) 929 2622, www.weirminerals.com

Market Forum

High Power Equipment ‘s (HPE) modified drill rig is designed to save time and offer additional safety aspects

Contact Pauline Bouwer to advertise in the “Mechanical Engineering Buyers Guide”.

Tel: (011) 781-1401, Fax: (011) 781-1403, Cell: 082-498-1693 or

Email:[email protected] for details

�� THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 60 July 2010

Tapered journals get a reconditioningIn April 2009 Mondi Merebank in Durban, requested SKF to conduct an urgent on-site assessment of four tapered journals fitted onto suction press roll heads.

The suction press rolls press moisture out of and consolidate the paper sheet, which then pass through various production stages to produce paper of different quality and thicknesses. Stoppages are simply not an option, but Mondi had run out of spare suction press roll journals which meant that if one of the operating journals failed, the machine would grind to a halt.

S a y s Re g a n Scheepers, from the SKF project engineering de-partment, “Mondi hoped the used journals would be suitable as spares but unfortunately, after inspecting the journals, this was not possi-ble.

There are two accepted repair methods for ta-pered journals, re-sleeving and welding. Accord-ing to Regan, re-sleeving is SKF’s preferred method of repair. “Because the customers’ first journal was

Market Forum

The Bosch Rexroth VarioFlow modular conveyor system with mat top chain

An explosive conveyer systemTectra Automation, through its system integrator, Vertex Automation has sup-

plied a complete conveyor system for use at an explosives manufacturing plant in eKandustria, Bronkhorstspruit.

Vertex was contracted by the explosives manufacturer to design, supply, construct and install two complete conveyor systems, including the SCADA system, in its new detonator assembly plant.

Koos Smit, Vertex managing director says, “Our client needed a system that is reliable, simple, offers fast cycle times, and is easy to maintain. A further requirement was for locally available spares to avoid lengthy downtime.”

a breakdown repair, we used the weld repair method,” he explains. The SKF project engineering department then presented a detailed re-sleeve design proposal to Mondi for restoring the remaining three tapered journals. SKF re-sleeved the journals to OEM standards and after final quality inspection by SKF, the journal was delivered to Mondi three month later.

Samantha Joubert , SKF South Africa, Tel: (011) 821 3500, Fax: (011) 821 3501, Email: [email protected], www.skf.co.za


Rubber assists a goldmineMultotec Rubber, a manufacturer of rubber wear products recently supplied two mill liners to Polysius for the Bisha Mining Share Company (BMSC) in Eritrea, a gold mine which has copper as a by-product.

“We sent the mill liners to site and our installation supervisors are overseeing the installation,” says Charles Els, sales manager at Multotec Rubber.

The liners are designed for a SAG mill with a 6.1m diameter, 3.6 metres in length and for a Ball mill with a 5.5m diameter and 8.6 metres in length.

“Rubber is more user-friendly and safer to handle and install. It seals well, practically eliminates clogging at grate plates and reduces noise. Its use in the diamond industry is particularly widespread because it doesn’t degrade diamonds,” he concludes.

Bernadette Wilson, Multotec Group, Tel: (011) 923 6193, Email: [email protected], www.multotec.com

Charles ElsLow TCO stainless steel submersiblesThe Lowara Z10 and Z12 stainless steel submersible pumps are corrosion and wear resistant, even in aggressive environments. The submersible series covers a wide performance range with five main sizes available.

The smallest is the Lowara Z10150 with a nominal flow rate of 150 m³/h, and the largest unit is the Lowara Z12420 with a nominal flow rate of 420 m³/h. The complete range offers heads of up to 545 metres and flow rates of up to 520 m³/h.

Furthermore, the pumps are suitable for a variety of applications including water supply from deep wells, pressure boosting and water distribution in civil and industrial systems, water level control, dewatering, fire fighting and irrigation.

For highly aggressive water environments, a full duplex version is also available.

With this new addition to the Lowara borehole family, the range of stainless steel borehole pumps now span from 4’’up to 12’’ pumps.

Lanelle Wheeler, ITT Water and Wastewater, Tel: (011) 966 9300, www.flygt.co.zaThe Lowara

stainless steel submersible pump

Market ForumTectra Automation supplied the aluminium profile, servo motors and drives, linear modules, and a VarioFlow modular conveyor system with mat top chain from Bosch Rexroth. Both systems have been completed and are currently in production.

Georg Venter, Tectra Automation, Tel: (011) 971 9400, Fax: (011) 971 9440, Email: [email protected]

High pressure sight glasses Spirax Sarco has released details of its latest range of 40 barg, high pressure sight glasses in carbon or stainless steel. The SGC40 (carbon steel) and SGS40 (stainless steel) double window sight glasses provide a solution for easy visual de-tection of flow, and are offered with an optional Mica insert for steam and high pH applications, or a flow indicator flap for enhanced flow indication.

With the pressure rating increased to PN40/ASME 300, the instruments are suited for a wider range of applications. The design incorporates double windows with a large viewing area and creates additional turbulence that allows easy inspection of flow media. Borosilicate glass windows provide a high level of safety and integrity.


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Market Forum

On the MoveSKF South Africa, has ap-pointed Barry Dailly as the new Managing Director for the local subsidiary of the Swedish multinational Group. Barry, who has been with SKF since 2007 in the capacity of Financial Manager, takes the reigns from previous Managing Director, Gavin Garland, who left South African shores at the end of April 2010 to fill a position at SKF in China.

Barry Dailly

The SGC40 and SGS40 provide a solution for easy inspection for the detection of flow such as detecting blocked valves, strainers, steam traps and other pipeline products. They can be used on other fluids other than steam and condensate within the food, pharmaceutical, OPC, institutions and gen-eral industry. Under certain conditions, corrosive elements in condensate can affect the inside face of the window, particularly where caustic, alkali and hydrofluoric acid is present. In these instances, Mica inserts should be used.

The SGC40 and SGS40 meet EN 10204 3.1 and ISO 9001 requirements, and fully comply with the requirements of the European Pressure Equipment Directive (PED) 97/23/EC and carry the CE mark when so required.

Emily Heath, Spirax Sarco, Tel: (011) 230-1300, Fax: (011) 393-1922, Email: [email protected], Website: www.spiraxsarco.com/za


Predictive Maintenance Conference

South Africa’s premier event focusing on predictive maintenance

and reliability engineering-based maintenance

“It’s all about UPTIME”

PdMSA 2010ABB Campus - 1 and 2 September 2010To register contact Riana van Buuren, ABB, Tel 010 202 5955 or go to: http://www.abb.co.za

This two-day event, to be held at the ABB Campus, Johannesburg, comprises a conference with more than 45 presentations by local and international experts and an

exhibition aimed at personnel responsible for the reliability and availability of equipment in the mining, utilities and industrial sectors.

same: jul 2010

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