bhel report blosk 3

8/10/2019 bhel report blosk 3

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1. INTRODUCTION

BHEL or the Bharat Heavy Engineering Limited is one of the largest engineeringand manufacturing organizations in the country and the BHEL, Haridwaris their gift to

Uttaranchal. With two large manufacturing plants, BHEL in Haridwar is among theleading industrial organizations in the state. It has established a Heavy ElectricalEquipment Plant or HEEP and a Central Foundry Forge Plant or CFFP in Haridwar.

The Heavy Electrical Equipment Plant in Haridwar designs and manufacturesturbo generators, AC and DC motors, gas turbines and huge steams. The Central Foundry

Forge Plant in Haridwar deals with steel castings and manufacturing of steel forgings.

BHEL was established more than 40 years ago when its first plant was setup in

Bhopal ushering in the indigenous Heavy Electrical Equipment Industry in India a dream

which has been more than realized with a well-recognized track record of performance it

has been earning profits continuously since 1971-72.

BHEL

1.1. OVERVIEW

Bharat Heavy Electricals Limited (B.H.E.L.) is the largest engineering

and manufacturing enterprise in India. BHEL caters to core sectors of the IndianEconomy viz., Power Generation's & Transmission, Industry, Transportation,

Telecommunication, Renewable Energy, Defense and many more.

The BHEL plants in Haridwar have earned the ISO - 9001 and 9002 certificates

for its high quality and maintenance. These two units have also earned the ISO - 14001certificates. Situate in Ranipur near Haridwar, the Bharat Heavy Engineering Limited

employs over 8,000 people.

BHEL is an integrated power plant equipment manufacturer and one of the largestengineering and manufacturing companies in India in terms of turnover. BHEL was

established in 1964, ushering in the indigenous Heavy Electrical Equipment industry inIndia - a dream that has been more than realized with a well-recognized track record ofperformance. The company has been earning profits continuously since 1971-72 and

paying dividends since 1976-77 .BHEL is engaged in the design, engineering,

manufacture, construction, testing, commissioning and servicing of a wide range ofproducts and services for the core sectors of the economy, viz. Power, Transmission,

Industry, Transportation, Renewable Energy, Oil & Gas and Defence.BHEL has 15

manufacturing divisions, two repair units, four regional offices, eight service centres,


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eight overseas offices and 15 regional centres and currently operate at more than 150

project sites across India and abroad. BHEL places strong emphasis on innovation and

creative development of new technologies. Our research and development (R&D) effortsare aimed not only at improving the performance and efficiency of our existing products,

but also at using state-of-the-art technologies and processes to develop new products.

This enables us to have a strong customer orientation, to be sensitive to their needs andrespond quickly to the changes in the market.The high level of quality & reliability of our products is due to adherence to

international standards by acquiring and adapting some of the best technologies from

leading companies in the world including General Electric Company, Alstom SA,Siemens AG and Mitsubishi Heavy Industries Ltd., together with technologies developed

in our own R&D centres. Most of our manufacturing units and other entities have been

accredited to Quality Management Systems (ISO 9001:2008), Environmental

Management Systems (ISO 14001:2004) and Occupational Health & Safety ManagementSystems (OHSAS 18001:2007).

BHEL has a share of around 59% in India's total installed generating capacitycontributing 69% (approx.) to the total power generated from utility sets (excluding non-

conventional capacity) as of March 31, 2012. We have been exporting our power and

industry segment products and services for approximately 40 years. We have exported

our products and services to more than 70 countries. We had cumulatively installedcapacity of over 8,500 MW outside of India in 21 countries, including Malaysia, Iraq, the

UAE, Egypt and New Zealand. Our physical exports range from turnkey projects to after

sales services.BHEL work with a vision of becoming a world-class engineering enterprise,

committed to enhancing stakeholder value.

Our greatest strength is our highly skilled and committed workforce of over

49,000 employees. Every employee is given an equal opportunity to develop himselfand grow in his career. Continuous training and retraining, career planning, a positive

work culture and participative style of management - all these have engendered

development of a committed and motivated workforce setting new benchmarks in termsof productivity, quality and responsiveness.


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1.2. WORKING AREAS

1.2.1. POWER GENERATION

Power generation sector comprises thermal, gas, hydro and nuclear power plantbusiness as of 31.03.2001, BHEL supplied sets account for nearly 64737 MW or 65% of

the total installed capacity of 99,146 MW in the country, as against nil till 1969-70.

BHEL has proven turnkey capabilities for executing power projects from

concept to commissioning, it possesses the technology and capability to produce thermalsets with super critical parameters up to 1000 MW unit rating and gas turbine generator

sets of up to 240 MW unit rating. Co-generation and combined-cycle plants have been

introduced to achieve higher plant efficiencies. To make efficient use of the high-ash-

content coal available in India, BHEL supplies circulating fluidized bed combustionboilers to both thermal and combined cycle power plants. The company manufactures

235 MW nuclear turbine generator sets and has commenced production of 500 MW

nuclear turbine generator sets.Custom made hydro sets of Francis, Pelton and Kaplan types for different head

discharge combination are also engineering and manufactured by BHEL. In all, orders

for more than 700 utility sets of thermal, hydro, gas and nuclear have been placed on theCompany as on date. The power plant equipment manufactured by BHEL is based on

contemporary technology comparable to the best in the world and is also internationally

competitive.

The Company has proven expertise in Plant Performance Improvement throughrenovation modernization and upgrading of a variety of power plant equipment besides

specialized know how of residual life assessment, health diagnostics and life extension

of plants.

1.2.2. POWER TRANSMISSION & DISTRIBUTION (T & D)

BHEL offer wide ranging products and systems for T & D applications. Products

manufactured include power transformers, instrument transformers, drytype transformers, series and stunt reactor, capacitor tanks, vacuum and SF circuit

breakers gas insulated switch gears and insulators.

A strong engineering base enables the Company to undertake turnkey delivery

of electric substances up to 400 kV level series compensation systems (for increasing

power transfer capacity of transmission lines and improving system stability and voltageregulation), shunt compensation systems (for power factor and voltage improvement)

and HVDC systems (for economic transfer of bulk power). BHEL hasindigenously developed the state-of-the-art controlled shunt reactor (for reactive

power management on long transmission lines). Presently a 400 kV Facts (Flexible AC

Transmission System) project under execution.


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1.2.3. INDUSTRIES

BHEL is a major contributor of equipment and systems to industries. Cement,sugar, fertilizer, refineries, petrochemicals, paper, oil and gas, metallurgical and other

process industries lines and improving system stability and voltage regulation, shunt

compensation systems (for power factor and voltage improvement) and HVDC systems(for economic transfer of bulk power) BHEL has indigenously developed the state-of-the-

art controlled shunt reactor (for reactive power management on long transmission lines).

Presently a 400 kV FACTS (Flexible AC Transmission System) projects is underexecution. The range of system & equipment supplied includes: captive power plants, co-

generation plants DG power plants, industrial steam turbines, industrial boilers and

auxiliaries. Water heat recovery boilers, gas turbines, heat exchangers and pressure

vessels, centrifugal compressors, electrical machines, pumps, valves, seamless steeltubes, electrostatic precipitators, fabric filters, reactors, fluidized bed combustion boilers,

chemical recovery boilers and process controls.

The Company is a major producer of large-size thruster devices. It also

supplies digital distributed control systems for process industries, and control &instrumentation systems for power plant and industrial applications. BHEL is the only

company in India with the capability to make simulators for power plants, defense and

other applications. The Company has commenced manufacture of large desalinationplants to help augment the supply of drinking water to people.

1.2.4. TRANSPORTATION

BHEL is involved in the development design, engineering, marketing, production,

installation, and maintenance and after-sales service of Rolling Stock and tractionpropulsion systems. In the area of rolling stock, BHEL manufactures electric locomotives

up to 5000HP, diesel-electric locomotives from 350 HP to 3100 HP, both for mainline andshunting duly applications. BHEL is also producing rolling stock for special

applications viz., overhead equipment cars, Special well wagons, Rail-cum-road vehicle

etc., Besides traction propulsion systems for in-house use, BHEL manufactures traction

propulsion systems for other rolling stock producers of electric locomotives, diesel-electric locomotives, electrical multiple units and metro cars. The electric and diesel

traction equipment on India Railways are largely powered by electrical propulsion

systems produced by BHEL. The company also undertakes retooling and overhauling

of rolling stock in the area of urban transportation systems. BHEL is geared up toturnkey execution of electric trolley bus systems, light rail systems etc. BHEL is also

diversifying in the area of port handing equipment and pipelines transportation system.

1.2.5. TELECOMMUNICATIONBHEL also caters to Telecommunication sector by way of small, medium

and large switching systems.


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1.2.6. RENEWABLE ENERGY

Technologies that can be offered by BHEL for exploiting non-conventional and

renewable sources of energy include: wind electric generators, solar photovoltaic

systems, solar lanterns and battery-powered road vehicles. The Company has taken upR&D efforts for development of multi-junction amorphous silicon solar cells and fuel

based systems.

1.2.7. INTERNATIONAL OPERATIONS

BHEL has, over the years, established its references in around 60 countries of

the world, ranging for the United States in the west to New Zealand in the far east. these

references encompass almost the entire product range of BHEL, covering turnkey powerprojects of thermal, hydro and gas-based types, substation projects, rehabilitation

projects, besides a wide variety of products, like transformers, insulators,

switchgears, heat exchangers, castings and forgings, valves, well-head equipment,

centrifugal compressors, photo-voltaic equipment etc. apart from over 1110mw ofboiler capacity contributed in Malaysia, and execution of four prestigious power projects

in Oman, some of the other major successes achieved by the company have been in

Australia, Saudi Arabia, Libya, Greece, Cyprus, Malta, Egypt, Bangladesh,Azerbaijan, Sri Lanka, Iraq etc.

The company has been successful in meeting demanding customer's requirements in

terms of complexity of the works as well as technological, quality and otherrequirements viz. extended warrantees, associated O&M, financing packages etc. BHEL

has proved its capability to undertake projects on fast-track basis. The company has

been successful in meeting varying needs of the industry, be it captive power plants,

utility power generation or for the oil sector requirements. Executing of overseas

projects has also provided BHEL the experience of working with world renownedconsulting organizations and inspection agencies.

In addition to demonstrated capability to undertake turnkey projects on its own, BHELpossesses the requisite flexibility to interface and complement with international

companies for large projects by supplying complementary equipment and meeting their

production needs for intermediate as well as finished products.

The success in the area of rehabilitation and life extension of power projects hasestablished BHEL as a comparable alternative to the original equipment manufacturers

(OEMS) for such plants.

1.3. TECHNOLOGY UPGRADATION AND RESEARCH & DEVELOPMENT

To remain competitive and meet customers' expectations, BHEL lays great

emphasis on the continuous up gradation of products and related technologies,

and development of new products. The Company has upgraded its products tocontemporary levels through continuous in house efforts as well as through acquisition

of new technologies from leading engineering organizations of the world.

The Corporate R&D Division at Hyderabad, spread over a 140 acre complex, leadsBHEL's research efforts in a number of areas of importance to BHEL's product range.


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Research and product development centers at each of the manufacturing divisions play

a complementary role. BHEL's Investment in R&D is amongst the largest in the

corporate sector in India. Products developed in-house during the last five yearscontributed about 8.6% to the revenues in 2000-2001.

BHEL has introduced, in the recent past, several state-of-the-art products

developed in-house: low-NOx oil / gas burners, circulating fluidized bedcombustion boilers, high-efficiency Pelton hydro turbines, petroleum depot

automation systems, 36 kV gas-insulated sub-stations, etc. The Company has also

transferred a few technologies developed in-house to other Indian companies forcommercialization.

Some of the on-going development & demonstration projects include:

Smart wall blowing system for cleaning boiler soot deposits, and micro-controller based

governor for diesel-electric locomotives. The company is also engaged in research infuturistic areas, such as application of super conducting materials in power generations

and industry, and fuel cells for distributed, environment-friendly power generation.

1.3.1 HUMAN RESOURCE DEVELOPMENT INSTITUTE

The most prized asset of BHEL is its employees. The Human Resource

Development Institute and other HRD centers of the Company help in not only keepingtheir skills updated and finely honed but also in adding new skills, whenever required.

Continuous training and retraining, positive, a positive work culture and

participative style of management, have engendered development of a committed andmotivated work force leading to enhanced productivity and higher levels of quality.

1.4. HEALTH, SAFETY AND ENVIRONMENT MANAGEMENT

BHEL, as an integral part of business performance and in its endeavor ofbecoming a world-class organization and sharing the growing global concern on issuesrelated to Environment. Occupational Health and Safety, is committed to protecting

Environment in and around its own establishment, and to providing safe and healthy

working environment to all its employees. For fulfilling these obligations, CorporatePolicies have been formulated as:

1.4.1. ENVIRONMENTAL POLICY

Compliance with applicable Environmental Legislation/Regulation;

Continual Improvement in Environment Management Systems to protect our

natural environment and Control Pollution; Promotion of activities for conservation of resources by Environmental

Management; Enhancement of Environmental awareness amongst employees, customers and

suppliers. BHEL will also assist and co-operate with the concerned GovernmentAgencies and Regulatory Bodies engaged in environmental activities, offering the

Company's capabilities is this field.


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1.4.2. OCCUPATIONAL HEALTH AND SAFETY POLICY

Compliance with applicable Legislation and Regulations; Setting objectives and targets to eliminate/control/minimize risks due to

Occupational and Safety Hazards;Appropriate structured training of employees on Occupational Health and Safety

(OH&S) aspects.

Formulation and maintenance of OH&S Management programs for continualimprovement;

Periodic review of OH&S Management System to ensure its continuingsuitability, adequacy and effectiveness;

Communication of OH&S Policy to all employees and interested parties.

The major units of BHEL have already acquired ISO 14001 Environmental

Management System Certification, and other units are in advanced stages of acquiringthe same. Action plan has been prepared to acquire OHSAS 18001 Occupational Health

and Safety Management System certification for all BHEL units.In pursuit of these Policy requirements, BHEL will continuously strive to improve

work particles in the light of advances made in technology and new understandings in

Occupational Health, Safety and Environmental Science. Participation in the "Global

Compact" of the United Nations.The "Global Compact" is a partnership between the United Nations, the business

community, international labor and NGOs. It provides a forum for them to work

together and improve corporate practices through co-operation rather than confrontation.

BHEL has joined the "Global Compact" of United Nations and has committed tosupport it and the set of core values enshrined in its nine principles.

1.4.3. PRINCIPLES OF THE "GLOBAL COMPACT" HUMAN RIGHTS

1. Business should support and respect the protection of internationally proclaimedhuman rights;

2. Make sure they are not complicit in human rights abuses.

LABOUR STANDARDS

3. Business should uphold the freedom of association and the effective recognition of

the right to collective bargaining;

4. The elimination of all form of forces and compulsory labor.5. The effective abolition of child labor, and

6. Eliminate discrimination.

ENVIRONMENT7. Businesses should support a precautionary approach to environmental challenges;

8. Undertake initiatives to promote greater environmental responsibility and


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9. Encourage the development and diffusion of environmentally friendly

technologies.

By joining the "Global Compact", BHEL would get a unique opportunity ofnetworking with corporate and sharing experience relating to social responsibility on

global basis.

1.5. BHEL UNITS

UNIT TYPE PRODUCT

1. Bhopal Heavy Electrical Plant Steam turbines , Turbo generators , Hydro

sets , Switch gear controllers

2. Haridwar

HEEP

CFFP

Heavy Electrical

Equipment Plant

Central Foundry ForgePlant

Hydro turbines , Steam turbines, Gas

turbine, Turbo generators, Heavy castings

and forging. Control panels, Light aircrafts,Electrical machines

3.Hyderabad

HPEP

Heavy Power Equipment

Plant

Industrial turbo sets, Compressors Pumps

and heaters, Bow mills, Heat exchangers oilrings, Gas turbines , Switch gears, Power

generating set

4.Tiruchi

HPBPSSTP

High Pressure Boiling

Plant

Steam less steel tubes, Spiral fin welded

tubes.

5.JhansiTP Transformer Plant Transformers, Diesel shunt less AC locos

and AC EMU

6.BangloreEDN

EPD

Control EquipmentDivision

Electro Porcelain Division

Energy meters, Water meters, Controlequipment, Capacitors, Photovoltaic panels,

Simulator, Telecommunication system, Otheradvanced microprocessor based control

system. Insulator and bushing, Ceramic

liners.

7.RanipetBAP

Boiler Auxiliaries Plant Electrostatic precipitator, Air pre-heater,Fans, Wind electric generators, Desalination

plants.

8.Goindwal Industrial Valves Plant Industrial valves and Fabrication

9.JagdishpurIP

Insulator Plant. High tension ceramic, Insulation Plates andbushings


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10.Rudrapur Component FabricationPlant

Windmill, Solar water heating system

11.Gurgoan Amorphous Silicon Solar

Cell Plant.

Solar Photovoltaic Cells, Solar lanterns

Chargers,Sl

ar clocks

TABLE 1

1.6 BHEL HARIDWAR

BHEL Har idwar consis ts of two manufactur ing uni ts , namely Heavy

Electrical

Equipment Plant (HEEP) and Central Foundry Forge Plant (CFFP), having area

HEEP area: - 8.45 sq. km

CFFP area: - 1.0 sq. kmThe Heavy Electricals Equipment Plant (HEEP) located in Haridwar, is one of the major

manufacturing plants of BHEL. The core business of HEEP includes design and

manufacture of large steam and gas turbines, turbo generators, hydro turbines andgenerators, large AC/DC motors and so on.

Central Foundry Forge Plant (CFFP) is engaged in manufacture of Steel Castings:

Upto 50 Tons per Piece Wt. & Steel Forgings: Up to 55 Tons per Piece Wt.

1.6.4. UNITS

There are two units in BHEL Haridwar as followed:

1) Heavy Electrical Equipment Plant (HEEP)2) Central Foundry Forge Plant (CFFP).

THERE ARE 8 BLOCKS IN HEEP

BLOCKS WORK PERFORMED IN THE BLOCK

I. Electrical Machine Turbo generator, generator exciter , motor (ac and dc)

II. Fabrication Large size fabricated assemblies or components

III. Turbine & Auxiliary Steam ,hydro ,gas turbines, turbine blade , special tooling

IV. Feeder Winding of Turbo ,hydro generators ,insulation for ac& dc motors

V. Fabrication Fabricated parts of steam turbine, water boxes, storage

tank, hydro turbine parts


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VI.FabricationStamping

and die manufacturingFabricated oil tanks, hollow guide blades, Rings, stator

frames and rotor spindle, all dies, stamping for

generators and motors

VII. Wood working Wooden packing, spacers.

VIII. Heaters & coolers LP heaters, ejectors, glands, steam and oil coolers, Oil tank,bearing covers

TABLE 2

THERE ARE 3 SECTIONS IN CFFP

TABLE 3

1.6.5. HEEP PRODUCT PROFILE

1. THERMAL SETS: Steam turbines and generators up to 500 MW capacity for utility and combined

cycle applications

Capability to manufacture up to 1000 MW unit cycle.

2. GAS TURBINES: Gas turbines for industry and utility application; range-3 to 200 MW (ISO). Gas turbines based co-generation and combined cycle system.

3. HYDRO SETS: Custom built conventional hydro turbine of Kaplan, Francis and Pelton with

matching generators up to 250 MW unit size. Pump turbines with matching motor-generators.

Mini / micro hydro sets. Spherical butterfly and rotary valves and auxiliaries for hydro station.

4. EQUIPMENT FOR NUCLEAR POWER PLANTS:Turbines and generators up to 500MW unit size.Steam generator up to 500MW unit size.Re-heaters / separators.

Heat exchangers and pressure vessels.

SECTIONS WORK PERFORMED IN THE SECTION

I. Foundry Casting of turbine rotor, casing and Francis runner

II. Forging Forging of small rotor parts

III. Machine shop Turning, boring, parting off, drilling etc.


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5. ELECTRICAL MACHINES:DC general purpose and rolling mill machines from 100 to 19000KW suitable for

operation on voltage up to 1200V. These are provided with STDP, totally enclosed

and duct ventilated enclosures.DC auxiliary mill motors.

6. CONTROL PANEL:Control panel for voltage up to 400KW and control desks for generating stations and

EMV substations.

7. CASTING AND FORGINGS:Sophisticated heavy casting and forging of creep resistant alloy steels, stainless steel

and other grades of alloy meeting stringent international specifications.

8. DEFENCE:Naval guns with collaboration of Italy.


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2. STEAM TURBINE

2.1 INTRODUCTION

A turbine is a device that converts chemical energy into mechanical energy,

specifically when a rotor of multiple blades or vanes is driven by the movement of a

fluid or gas. In the case of a steam turbine, the pressure and flow of newly condensedsteam rapidly turns the rotor. This movement is possible because the water to steam

conversion results in a rapidly expanding gas. As the turbines rotor turns, the rotating

shaft can work to accomplish numerous applications, often electricity generation.

FIG.1 STEAM TURBINE

In a steam turbine, the steams energy is extracted through the turbine and the steamleaves the turbine at a lower energy state. High pressure and temperature fluid at the

inlet of the turbine exit as lower pressure and temperature fluid. The difference is

energy converted by the turbine to mechanical rotational energy, less any

aerodynamic and mechanical inefficiencies incurred in the process. Since the fluid isat a lower pressure at the exit of the turbine than at the inlet, it is common to say the

fluid has been expanded across the turbine. Because of the expanding

flow, higher volumetric flow occurs at the turbine exit (at least for compressible

fluids) leading to the need for larger turbine exit areas than at the inlet.

The generic symbol for a turbine used in a flow diagram is shown inFigure below. The symbol diverges with a larger area at the exit than at the inlet.

This is how one can tell a turbine symbol from a compressor symbol. In Figure,the graphic is colored to indicate the general trend of temperature drop through a

turbine. In a turbine with a high inlet pressure, the turbine blades convert this pressure

energy into velocity or kinetic energy, which causes the blades to rotate. Many greencycles use a turbine in this fashion, although the inlet conditions may not be the same

as for a conventional high pressure and temperature steam turbine. Bottoming cycles,


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for instance, extract fluid energy that is at a lower pressure and temperature than a

turbine in a conventional power plant. A bottoming cycle might be used to extract

energy from the exhaust gases of a large diesel engine, but the fluid in a bottomingcycle still has sufficient energy to be extracted across a turbine, with the energy

converted into rotational energy.

FIG.2 FLOW DIAGRAM OF A STEAM TURBINE

Turbines also extract energy in fluid flow where the pressure is not high but where

the fluid has sufficient fluid kinetic energy. The classic example is a wind turbine, which

converts the winds kinetic energy to rotational energy. This type of kinetic energy

conversion is common in green energy cycles for applications ranging from larger windturbines to smaller hydrokinetic turbines currently being designed for and demonstrated

in river and tidal applications. Turbines can be designed to work well in a variety of

fluids, including gases and liquids, where they are used not only to drive generators, but

also to drive compressors or pumps.

One common (and somewhat misleading) use of the word turbine is gas turbine,as in a gas turbine engine. A gas turbine engine is more than just a turbine and typically

includes a compressor, combustor and turbine combined to be a self-contained unit usedto provide shaft or thrust power. The turbine component inside the gas turbine still

provides power, but a compressor and combustor are required to make a self-contained system that needs only the fuel to burn in the combustor.

An additional use for turbines in industrial applications that may also be

applicable in some green energy systems is to cool a fluid. As previously mentioned,when a turbine extracts energy from a fluid, the fluid temperature is reduced. Some

industries, such as the gas processing industry, use turbines as sources of refrigeration,

dropping the temperature of the gas going through the turbine. In other words, the

primary purpose of the turbine is to reduce the temperature of the working fluid asopposed to providing power. Generally speaking, the higher the pressure ratio across a

turbine, the greater the expansion and the greater the temperature drop. Even whereturbines are used to cool fluids, the turbines still produce power and must be connectedto a power absorbing device that is part of an overall system.

Also note that turbines in high inlet-pressure applications are sometimes called expanders.

The terms turbine and expander can be used interchangeably for most applications,but expander is not used when referring to kinetic energy applications, as the fluid

does not go through significant expansion.


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2.2. ADVANTAGES:- Ability to utilize high pressure and high temperature steam.

High efficiency. High rotational speed.

High capacity/weight ratio. Smooth, nearly vibration-free operation. No internal lubrication. Oil free exhausts steam.

2.3 DISADVANTAGES:-

For slow speed application reduction gears are required. The steam turbine

cannot be made reversible. The efficiency of small simple steam turbines is poor.

2.4 STEAM TURBINES THE MAINSTAY OF BHEL BHEL has the capability to design, manufacture and commission steam turbines

of up to 1000 MW rating for steam parameters ranging from 30 bars to 300 bars

pressure and initial & reheat temperatures up to 600 C. Turbines are built on the building block system, consisting of modules suitable

for a range of output and steam parameters.For a desired output and steam parameters appropriate turbine blocks can be

selected.


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3. TYPES OF STEAM TURBINE

There are complicated methods to properly harness steam power that give rise to thetwo primary turbine designs: impulse and reaction turbines. These different designs

engage the steam in a different method so as to turn the rotor.

3.1 IMPULSE TURBINEThe principle of the impulse steam turbine consists of a casing containing stationarysteam nozzles and a rotor with moving or rotating buckets.

The steam passes through the stationary nozzles and is directed at high velocity

against rotor buckets causing the rotor to rotate at high speed.

The following events take place in the nozzles:

1. The steam pressure decreases.

2. The enthalpy of the steam decreases.

3. The steam velocity increases.

4. The volume of the steam increases.

5. There is a conversion of heat energy to kinetic energy as the heat energy from thedecrease in steam enthalpy is converted into kinetic energy by the increased steam

velocity.

3.2 THE IMPULSE PRINCIPLE

If steam at high pressure is allowed to expand through stationary nozzles, the resultwill be a drop in the steam pressure and an increase in steam velocity. In fact, the steam

will issue from the nozzle in the form of a high-speed jet. If this high steam is applied to

a properly shaped turbine blade, it will change in direction due to the shape of the blade.The effect of this change in direction of the steam flow will be to produce an impulse

force, on the blade causing it to move. If the blade is attached to the rotor of a turbine,

then the rotor will revolve. Force applied to the blade is developed by causing the steam

to change direction of flow (Newtons 2ND Law change of momentum). The

change of momentum produces the impulse force. The fact that the pressure does not

drop across the moving blades is the distinguishing feature of the impulse turbine. Thepressure at the inlet to the moving blades is the same as the pressure at the outlet from

the moving blades.


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3.3 REACTION PRINCIPLE

A reaction turbine has rows of fixed blades alternating with rows of moving

blades. The steam expands first in the stationary or fixed blades where it gains somevelocity as it drops in pressure. It then enters the moving blades where its direction offlow is changed thus producing an impulse force on the moving blades. In addition,

however, the steam upon passing through the moving blades again expands and further

drops in pressure giving a reaction force to the blades. This sequence is repeated as thesteam passes through additional rows of fixed and moving blades.

3.4 IMPULSE TURBINE STAGING

In order for the steam to give up all its kinetic energy to the moving blades in an

impulse turbine, it should leave the blades at zero absolute velocity. This condition willexist if the blade velocity is equal to one half of the steam velocity. Therefore, for good

efficiency the blade velocity should be about one half of steam velocity.

In order to reduce steam velocity and blade velocity, the following methods maybe used:

1. Pressure compounding.

2.Velocity compounding.

3. Pressure-velocity compounding.

4.Pressure Compounding


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4. TURBINE PARTS

4.1 TURBINE BLADES Cylindrical reaction blades for HP, IP and LP Turbines 3-DS blades, in initial stages of HP and IP Turbine, to reduce secondary losses.

Twisted blade with integral shroud, in last stages of HP, IP and initial stages ofLP turbines, to reduce profile and Tip leakage losses

Free standing LP moving blades Tip sections with supersonic design

Fir-tree root

Flame hardening of the leading edge Banana type hollow guide blade

Tapered and forward leaning for optimized mass flow distribution

Suction slits for moisture removal

4.2 TURBINE CASING

Casings or cylinders are of the horizontal split type. This is not ideal, as the heavyflanges of the joints are slow to follow the temperature changes of the cylinder walls.

However, for assembling and inspection purposes there is no other solution. The casingis heavy in order to withstand the high pressures and temperatures. It is general practice

to let the thickness of walls and flanges decrease from inlet- to exhaust-end.

The casing joints are made steam tight, without the use of gaskets, by matching theflange faces very exactly and very smoothly. The high pressure is applied to the inner

casing, which is open at the exhaust end, letting the turbine exhaust to the outer casings.

4.3 TURBINE ROTORS

The design of a turbine rotor depends on the operating principle of the turbine. The

impulse turbine with pressure drop across the stationary blades must have seals betweenstationary blades and the rotor. The smaller the sealing area, the smaller the leakage;

therefore the stationary blades are mounted in diaphragms with labyrinth seals around the

shaft. This construction requires a disc rotor. Basically there are two types of rotor:

DISC ROTORS

All larger disc rotors are now machined out of a solid forging of nickel steel; this shouldgive the strongest rotor and a fully balanced rotor. It is rather expensive, as the weight of

the final rotor is approximately 50% of the initial forging. Older or smaller disc rotors

have shaft and discs made in separate pieces with the discs shrunk on the shaft. The bore

of the discs is made 0.1% smaller in diameter than the shaft. The discs are then heated

until they easily are slid along the shaft and located in the correct position on the shaft andshaft key. A small clearance between the discs prevents thermal stress in the shaft.

DRUM ROTORS

The first reaction turbines had solid forged drum rotors. They were strong, generally well

balanced as they were machined over the total surface. With the increasing size ofturbines the solid rotors got too heavy pieces. For good balance the drum must be

machined both outside and inside and the drum must be open at one end. The second part

of the rotor is the drum end cover with shaft.


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5. CONSTRUCTIONAL FEATURES OF A BLADE

The blade can be divided into 3 parts: The profile, which converts the thermal energy of steam into kinetic energy, with a

certain efficiency depending upon the profile shape.

The root, which fixes the blade to the turbine rotor, giving a proper anchor to theblade, and transmitting the kinetic energy of the blade to the rotor.

The damping element, which reduces the vibrations which necessarily occur inthe blades due to the steam flowing through the blades. These damping elements

may be integral with blades, or they may be separate elements mounted between the

blades.

5.2 CLASSIFICATION OF PROFILES

There are two basic types of profiles - Impulse and Reaction. In the impulse type

of profiles, the entire heat drop of the stage occurs only in the stationary blades. In the

reaction type of blades, the heat drop of the stage is distributed almost equally betweenthe guide and moving blades.

Though the theoretical impulse blades have zero pressure drop in the moving

blades, practically, for the flow to take place across the moving blades, there must be asmall pressure drop across the moving blades also. Therefore, the impulse stages in

practice have a small degree of reaction. These stages are therefore more accurately,

though less widely, described as low-reaction stages.The presently used reaction profiles are more efficient than the impulse profiles at

part loads. This is because of the more rounded inlet edge for reaction profiles. Due to

this, even if the inlet angle of the steam is not tangential to the pressure-side profile of the

blade, the losses are low.

However, the impulse profiles have one advantage. The impulse profiles can takea large heat drop across a single stage, and the same heat drop would require a greater

number of stages if reaction profiles are used, thereby increasing the turbine length.

The Steam turbines use the impulse profiles for the control stage (1st stage), and

the reaction profiles for subsequent stages. There are three reasons for using impulseprofile for the first stage.

a) Most of the turbines are partial arc admission turbines. If the first stage is a

reaction stage, the lower half of the moving blades do not have any inlet

steam, and would ventilate. Therefore, most of the stage heat drop shouldoccur in the guide blades.

b) The heat drop across the first stage should be high, so that the wheel chamber of theouter casing is not exposed to the high inlet parameters. In case of -4 turbines, the

inner casing parting plane strength becomes the limitation, and therefore requires a

large heat drop across the 1st stage.

c) Nozzle control gives better efficiency at part loads than throttle control.

d) The number of stages in the turbine should not be too high, as this willincrease the length of the turbine


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6. MANUFACTURING PROCESS

6.1 INTRODUCTIONManufacturing process is that part of the production process which is directly

concerned with the change of form or dimensions of the part being produced. It does notinclude the transportation, handling or storage of parts, as they are not directlyconcerned with the changes into the form or dimensions of the part produced.

Manufacturing is the backbone of any industrialized nation. Manufacturing and

technical staff in industry must know the various manufacturing processes,materials being processed, tools and equipments for manufacturing different

components or products with optimal process plan using proper precautions and

specified safety rules to avoid accidents. Beside above, all kinds of the future engineers

must know the basic requirements of workshop activities in term of man, machine,material, methods, money and other infrastructure facilities needed to be positioned

properly for optimal shop layouts or plant layout and other support services effectively

adjusted or located in the industry or plant within a well-planned manufacturingorganization.

Todays competitive manufacturing era of high industrial development and

research, is being called the age of mechanization, automation and computer integrated

manufacturing. Due to new researches in the manufacturing field, the advancement hascome to this extent that every different aspect of this technology has become a

full- fledged fundamental and advanced study in itself. This has led to introduction

of optimized design and manufacturing of new products. New developments in

manufacturing areas are deciding to transfer more skill to the machines for considerablyreduction of manual labor.

6.2 CLASSIFICATION OF MANUFACTURING PROCESSES

For producing of products materials are needed. It is therefore important to

know the characteristics of the available engineering materials. Raw materials used

manufacturing of products, tools, machines and equipments in factories or industries

are for providing commercial castings, called ingots. Such ingots are then processedin rolling mills to obtain market form of material supply in form of bloom, billets, slabs

and rods.

These forms of material supply are further subjected to various manufacturing processes

for getting usable metal products of different shapes and sizes in various manufacturingshops. All these processes used in manufacturing concern for changing the ingots into

usable products may be classified into six major groups as

Primary shaping processes

Secondary machining processes Metal forming processes Joining processes

Surface finishing processes and Processes effecting change in properties


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6.2.1 PRIMARY SHAPING PROCESSES

Primary shaping processes are manufacturing of a product from an amorphous material.

Some processes produces finish products or articles into its usual form whereas others do

not, and require further working to finish component to the desired shape and size. Theparts produced through these processes may or may not require to undergo further

operations. Some of the important primary shaping processes are:

(1) Casting

(2) Powder metallurgy(3) Plastic technology

(4) Gas cutting

(5) Bending and(6) Forging

6.2.2 SECONDARY OR MACHINING PROCESSES

As large number of components require further processing after the primaryprocesses. These components are subjected to one or more number of machining

operations in machine shops, to obtain the desired shape and dimensional accuracy on flat

and cylindrical jobs. Thus, the jobs undergoing these operations are the roughly finished

products received through primary shaping processes. The process of removing theundesired or unwanted material from the work-piece or job or component to produce a

required shape using a cutting tool is known as machining. This can be done by a manual

process or by using a machine called machine tool (traditional machines namely lathe,

milling machine, drilling, shaper, planner, slitter). In many cases these operations areperformed on rods, bars and flat surfaces in machine shops.

These secondary processes are mainly required for achieving dimensionalaccuracy and a very high degree of surface finish. The secondary processes require the

use of one or more machine tools, various single or multi-point cutting tools (cutters), job

holding devices, marking and measuring instruments, testing devices and gauges etc. forgetting desired dimensional control and required degree of surface finish on the work-

pieces. The example of parts produced by machining processes includes hand tools

machine tools instruments, automobile parts, nuts, bolts and gears etc. Lot of material is

wasted as scrap in the secondary or machining process.


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7. BLOCK 3 LAY-OUT

TABLE-4: LAYOUT OF BLOCK-3


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8. CLASSIFICATION OF BLOCK 3

BAY-1 IS FURTHER DIVIDED INTO THREE PARTS

1. HMS -

In this shop heavy machine work is done with the help of different NC & CNCmachines such as center lathes, vertical and horizontal boring & milling machines.

Asias largest vertical boring machine is installed here and CNC horizontal boring

milling machines from Skoda of Czechoslovakia.

2. Assembly Section (of hydro turbines) In this section assembly of hydro turbines are done. Blades of turbine are 1st assemble

on the rotor & after it this rotor is transported to balancing tunnel where the balancing isdone. After balancing the rotor, rotor & casings both internal & external are transported

to the customer. Total assembly of turbine is done in the company which

purchased it by B.H.E.L.

3. OSBT (over speed balancing tunnel)-

In this section, rotors of all type of turbines like LP(low pressure), HP(high

pressure)& IP(Intermediate pressure) rotors of Steam turbine , rotors of Gas & Hydroturbine are balanced .In a large tunnel, Vacuum of 2 torr is created with the help of

pumps & after that rotor is placed on pedestal and rotted with speed of 2500-4500 rpm.

After it in a computer control room the axis of rotation of rotor is seen with help of

computer & then balance the rotor by inserting the small balancing weight in thegrooves cut on rotor.

FIG.3 OVERSPEED AND VACCUM BALANCING TUNNEL


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For balancing and over speed testing of rotors up to 320 tons in weight, 1800 mm inlength and 6900 mm diameter under vacuum conditions of 1Torr.

BAY 2 IS DIVIDED IN TO 2 PARTS:

1. HMS In this shop several components of steam turbine like LP, HP & IP rotors,

Internal & external casing are manufactured with the help of different operations carriedout through different NC & CNC machines like grinding, drilling, vertical &

horizontal milling and boring machines, center lathes, planer, Kopp milling machine.

2 .Assembly section In this section assembly of steam turbines up to 1000 MW Isassembled. 1st moving blades are inserted in the grooves cut on circumferences of rotor,

then rotor is balanced in balancing tunnel in bay-1. After is done in which guide blades

are assembled inside the internal casing & then rotor is fitted inside this casing. After

it this internal casing with rotor is inserted into the external.

BAY 3 IS DIVIDED INTO 3 PARTS:

1. Bearing section In this section Journal bearings are manufactured which are used

in turbines to overcome the vibration & rolling friction by providing the proper

lubrication.

2. Turning section In this section small lathe machines, milling & boringmachines, grinding machines & drilling machines are installed. In this section small jobs

are manufactured like rings, studs, disks etc.

3. Governing section In this section governors are manufactured. These governors

are used in turbines for controlling the speed of rotor within the certain limits. 1st allcomponents of governor are made by different operations then these all parts aretreated in heat treatment shop for providing the hardness. Then these all components

are assembled into casing. There are more than 1000 components of Governor.

BAY-4 IS DIVIDED INTO 3 PARTS:

1. TBM (turbine blade manufacturing) shop- In this shop solid blade of both steam

& gas turbine are manufactured. Several CNC & NC machines are installed here

such as Copying machine, Grinding machine, Rhomboid milling machine, Duplex

milling machine, T- root machine center, Horizontal tooling center, Vertical &horizontal boring machine etc.


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FIG.4 STEAM TURBINE CASING

2. Turning section- Same as the turning section in Bay-3, there are several small

machine like lathes machines, milling, boring, grinding machines etc.

FIG.5 CNC ROTOR TURNING LATHE

Heat treatment shop-

In this section there are several tests performed for checking the hardness ofdifferent components. Tests performed are Sterelliting, Nitriding, and DP test.


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9. BLADE SHOP

Blade shop is an important shop of Block 3. Blades of all the stages of turbine are made

in this shop only. They have a variety of centre lathe and CNC machines to perform the

complete operation of blades. The designs of the blades are sent to the shop and the

Respective job is distributed to the operators. Operators perform their job in a fixedinterval of time.

9.1 TYPES OF BLADESBasically the design of blades is classified according to the stages of turbine. The size ofLP TURBINE BLADES is generally greater than that of HP TURBINE BLADES. At the

first T1, T2, T3 & T4 kinds of blades were used, these were 2nd generation blades. Then

it was replaced by TX, BDS (for HP TURBINE) & F shaped blades. The most modernblades are F & Z shaped blades.

9.2 OPERATIONS PERFORMED ON BLADES

Some of the important operations performed on blade manufacturing are:-

Milling Blank Cutting Grinding of both the surfaces

Cutting

Root milling

9.3 MACHINING OF BLADESMachining of blades is done with the help of Lathe & CNC machines. Some of themachines are:-

Centre lathe machine Vertical Boring machine

Vertical Milling machine CNC lathe machin

9.4 NEW BLADE SHOP

A new blade shop is being in operation, mostly 500MW turbine blades are manufacturedin this shop. This is a highly hi tech shop where complete manufacturing of blades is

done using single advanced CNC machines. Complete blades are finished using

modernized CNC machines. Some of the machines are:-

Pama CNC ram boring machine Wotum horizontal machine with 6 axis CNC control CNC shaping machine


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10. CONCLUSION

Gone through rigorous one month training under the guidance of capable engineers and

workers of BHEL Haridwar in Block-3 TURBINEMANUFACTURINGheaded by

Senior Engineer of department Mr. Jaykesh Kumar situated in Ranipur, Haridwar,

Uttarakhand.

The training was specified under the Turbine Manufacturing Department. Working under

the department I came to know about the basic machining processes which were required

for manufacturing of steam turbines. Duty lathes were also planted in the same linewhere the specified work was undertaken.

The training brought to my knowledge the various machining and fabrication

processes went not only in the manufacturing of blades but other parts of the turbine also.


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REFERENCES

1. http://www.bhel.com/about.php

2. http://en.wikipedia.org/wiki/Bharat_Heavy_Electricals

3. http://economictimes.indiatimes.com/bharat-heavy-electricals-

ltd/infocompanyhistory/companyid-11831.cms4. http://en.wikipedia.org/wiki/Steam_turbine

bhel report blosk 3

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