nes 323 requirements for centrifuges

Requirements for Centrifuges

Ministry of Defence Defence Standard 02-323 (NES 323)

Issue 2 Publication Date 1 June 2001

Category 3

AMENDMENTS ISSUED SINCE PUBLICATION

AMD NO DATE OFISSUE

TEXT AFFECTED SIGNATURE &DATE

Revision Note

This Issue of this Standard has been prepared to incorporate changes to text and presentation.The technical content has been updated in line with current practice.

Historical Record

Def Stan 02-323/Issue 1 1 April 2000NES 323 Issue 4 October 1991NES 323 Issue 3 November 1986NES 323 Issue 2 April 1981NES 323 Issue 1 September 1979

(i)

DEFENCE STANDARD 02323 (NES 323)

REQUIREMENTS FOR CENTRIFUGES

ISSUE 2

This Defence Standard is

authorized for use in MOD contracts

by the Defence Procurement Agency and

the Defence Logistics Organization

Published by:

Defence Procurement Agency,An Executive Agency of The Ministry of Defence,Directorate of Standardization,Kentigern House,65 Brown Street,Glasgow, G2 8EX.

DEF STAN 02323 / ISSUE 2(NES 323)

(ii)


(iii)

SCOPE1. This Defence Standard gives the requirements for power driven oil centrifuges in HM Surface

Ships and Submarines. It does not cover autopowered centrifugal filters.

2. Oil centrifuges are used in lubricating oil, fuel oil and hydraulic oil systems.

3. Centrifuge installations include:

a. Oil supply and discharge pumps with associated relief valves. The supply pump may beseparately mounted and powered;

b. Oil suction strainer;

c. Oil heater, for centrifuges other than fuel centrifuges;

d. Interconnecting pipework connected to centrifuge (shipbuilders supply);

e. Operating water tank and other water supplies with valves and strainers;

f. Antiflood tank, for nonselfcleaning centrifuges;

g. Sludge tank (shipbuilders supply) for selfcleaning centrifuges.

4. The following installation boundaries apply:

a. Oil inlet and outlet connections;

b. Water supplies to operating water tank and centrifuges;

c. Water outlet from antiflood tank, for nonselfcleaning centrifuges;

d. Water and sludge outlets to sludge tank, for selfcleaning centrifuges;

e. Electrical terminals on starters, controls and instruments.


(iv)


(v)

FOREWORD

Sponsorship1. This Naval Engineering Standard (NES) is sponsored by the Defence Logistics Organisation

(DLO), Ministry of Defence (MOD).

2. Any user of this NES either within MOD or in industry may propose an amendment to it.Proposals for amendments that are not directly applicable to a particular contract are to bemade to the publishing authority identified on Page (i), and those directly applicable to aparticular contract are to be dealt with using contract procedures.

3. If it is found to be unsuitable for any particular requirement, MOD is to be informed in writingof the circumstances.

4. No alteration is to be made to this NES except by the issue of an authorized amendment.

5. Unless otherwise stated, reference in this NES to approval, approved, authorized and similarterms means by the MOD in writing.

6. Any significant amendments that may be made to this NES at a later date will be indicatedby a vertical sideline. Deletions will be indicated by 000 appearing at the end of the lineinterval.

7. Extracts from British Standards quoted within this NES have been included with thepermission of the British Standards Institution.

8. This NES has been reissued to reflect changes in departmental nomenclature and the changesto technical requirements.

Conditions of Release

General9. This NES has been devised solely for the use of the MOD, and its contractors in the execution

of contracts for the MOD. To the extent permitted by law, the MOD hereby excludes all liabilitywhatsoever and howsoever arising (including but without limitation, liability resulting fromnegligence) for any loss or damage however caused when the NES is used for any otherpurpose.

10. This document is Crown Copyright and the information herein may be subject to Crown orthird party rights. It is not to be released, reproduced or published without written permissionof the MOD.

11. The Crown reserves the right to amend or modify the contents of this NES without consultingor informing any holder.

MOD Tender or Contract Process12. This NES is the property of the Crown. Unless otherwise authorized in writing by the MOD

it must be returned on completion of the contract, or submission of the tender, in connectionwith which it is issued.

13. When this NES is used in connection with a MOD tender or contract, the user is to ensure thathe is in possession of the appropriate version of each document, including related documents,relevant to each particular tender or contract. Enquiries in this connection may be made tothe authority named in the tender or contract.

14. When NES are incorporated into MOD contracts, users are responsible for their correctapplication and for complying with contractual and any other statutory requirements.Compliance with an NES does not of itself confer immunity from legal obligations.


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Categories of NES15. The Category of this NES has been determined using the following criteria:

a. Category 1. If not applied may have a Critical affect on the following:

Safety of the vessel, its complement or third parties.

Operational performance of the vessel, its systems or equipment.

b. Category 2. If not applied may have a Significant affect on the following:

Safety of the vessel, its complement or third parties.

Operational performance of the vessel, its systems or equipment.

Through life costs and support.

c. Category 3. If not applied may have a Minor affect on the following:

MOD best practice and fleet commonality.

Corporate Experience and Knowledge.

Current support practice.

Related Documents16. In the tender and procurement processes the related documents listed in each section and

Annex A can be obtained as follows:

a. British Standards British Standards Institution,389 Chiswick High Road,London, W4 4AL.

b. Defence Standards, including Defence Procurement Agency,Naval Engineering Standards An Executive Agency of The Ministry of Defence,

Directorate of Standardization,Kentigern House,65 Brown Street,Glasgow, G2 8EX.

c. Other documents Tender or Contract Sponsor to advise.

17. All applications to Ministry Establishments for related documents are to quote the relevantMOD Invitation to Tender or Contract number and date, together with the sponsoringDirectorate and the Tender or Contract Sponsor.

18. Prime Contractors are responsible for supplying their subcontractors with relevantdocumentation, including specifications, standards and drawings.

Health and SafetyWarning

19. This NES may call for the use of processes, substances and/or procedures that are injuriousto health if adequate precautions are not taken. It refers only to technical suitability and inno way absolves either the supplier or the user from statutory obligations relating to healthand safety at any stage of manufacture or use. Where attention is drawn to hazards, thosequoted may not necessarily be exhaustive.

20. This NES has been written, and is to be used, taking into account the policy stipulated inJSP430: MOD Ship Safety Management System Handbook.

Additional Information(There is no relevant information included)


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CONTENTSPage No

TITLE PAGE (i). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SCOPE (iii). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FOREWORD (v). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sponsorship (v). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conditions of Release (v). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Categories of NES (vi). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Related Documents (vi). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Health and Safety (vi). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CONTENTS (vii). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 1. PERFORMANCE SPECIFICATION 1.1. . . . . . . . . . . . . . . . . . 1.1 Safety 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Centrifuges 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 Centrifuge Performance 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Pumping Equipment Performance 1.2. . . . . . . . . . . . . . . . . . . . . 1.5 Motors 1.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6 Oil Heater Performance 1.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.7 Information Required from Manufacturer 1.3. . . . . . . . . . . . . . 1.8 Installation 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8.1 Centrifuges 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8.2 Lifting Gear 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.9 Testing 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 2. NATIONAL/INTERNATIONAL REGULATIONS 2.1. . . . . . . 2.1 Lifting Operations 2.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 3. MILITARY STANDARDS/REQUIREMENTS 3.1. . . . . . . . . . . 3.1 Lubrication 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Drawings 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3 Environmental Conditions 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.1 General 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.2 Vibrational Environment 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.3 Noise and Vibration 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.4 Shock 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4 Pumps 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 Motors and Starters 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.6 Strainers 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.7 Oil Heaters 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


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Page No3.8 Tanks 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.9 Valves 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.10 Pipework 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.11 Flexible Connections 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.12 Shock Mountings 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.13 Sampling Connections 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.14 Manufacturing Requirements 3.2. . . . . . . . . . . . . . . . . . . . . . . . . 3.15 Installation Requirements 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.15.1 Centrifuges 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.15.2 Electrical Connections 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.15.3 Cleanliness 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.15.4 Flushing 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.16 Test Requirements 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 4. DESIGN REQUIREMENTS/GUIDANCE 4.1. . . . . . . . . . . . . . 4.1 Safety 4.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 General 4.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Pumps 4.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Strainers 4.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 Oil Heaters 4.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6 Tanks 4.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6.1 Anti-flood Tank 4.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6.2 Sludge Tank 4.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6.3 Operating Water Tank 4.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7 Flexible Connections 4.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8 Pipework 4.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9 Control and Instrumentation 4.3. . . . . . . . . . . . . . . . . . . . . . . . . 4.9.1 Control 4.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9.2 Instrumentation 4.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 5. CORPORATE EXPERIENCE & KNOWLEDGE 5.1. . . . . . . .

ANNEX A. RELATED DOCUMENTS A.1. . . . . . . . . . . . . . . . . . . . . . . . . .

ANNEX B. ABBREVIATIONS AND DEFINITIONS B.1. . . . . . . . . . . . . . .

ANNEX C. PROCUREMENT CHECK LIST C.1. . . . . . . . . . . . . . . . . . . . .

ALPHABETICAL INDEX INDEX 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


1.1

1. PERFORMANCE SPECIFICATION

Related Documents: BS EN 292; BS EN 10088 Part 1; BS EN 12547;BS 4999 Part 111; DEF STAN 015; ASTM D95; see also Annex A.

1.1 Safety

a . Centrifuges are to be designed and manufactured to withstand the loadsassociated with the specified and reasonably foreseeable operating andmaintenance conditions, without endangering the health and safety of exposedpersons.

b . Significant hazards associated with centrifuges include the ejection of parts dueto:

(1) Rotor rupture and ejection;

(2) Parts working loose from the rotor and being ejected;

(3) Stationary parts being ejected.

c . To ensure that the centrifuge is safe for its intended use thedesigner/manufacturer is to adhere to the guidance in BS EN 292. Commonsafety requirements for centrifuges are given in BS EN 12547.

1.2 Centrifuges

a . Centrifuges are to be fully automatic in operation and be constructed andarranged to provide continuous removal of water and solids from oil. Thecentrifuge is to be capable of manual operation.

b . Automatic cleaning and automatic change over between tanks is to be provided.

c . The shell, hood, intermediate discs and other components which come intocontact with the medium being separated are to be manufactured in stainlesssteel to BS EN 10088 Part 1 1.4401.

1.3 Centrifuge Performance

a . Centrifuges are to achieve the standard of solid particle extraction and of solidand water extraction defined below when operating at the specified output andsupplied with:

(1) Lubricating oils at any viscosity in the range of 18 mm2/s to 24 mm2/s(centistokes) and densities in the range of 0.84 g/ml to 0.925 g/ml;

(2) Fuel oils at any viscosity in the range of 2 mm2/s to 14.5 mm2/s(centistokes) and densities in the range of 0.8 g/ml to 0.85 g/ml.

b . When the test oil contains 1% by weight of 700 grade carborundum and 5%volume of fresh water, the maximum and average mean particle sizes in the oildischarged after one pass are not to exceed 10 and 4 microns respectively.

NOTE Mean particle size is the nominal size, for filtration purposes, of any particle of indeterminate shape and is taken to be thearithmetic mean of the length and breadth measured at rightangles in the plane of view.


1.2

1.4 Pumping Equipment Performance

a . Centrifuge supply pumps are to deliver the rated throughput of the centrifugewhen supplied with:

(1) Aerated lubricating oil having a viscosity in the range of 18 mm2/s to24 mm2/s (centistokes);

NOTE Aerated oil is a mixture, comprising by volume, of 90% oil and10% air at 1 bar absolute at 80C.

(2) Fuel oil having a viscosity in the range of 2 mm2/s to 14.5 mm2/s(centistokes).

NOTE Graphs of Viscosity Characteristics can be found inDEF STAN 01-5.

b . Lubricating oil centrifuge supply pumps are to be capable of pumping oil ofviscosities up to a maximum of 2000 mm2/s (centistokes) when starting up.

c . Each integral supply pump is to supply the rated output when operating with aspecified negative manometric suction head.

d . The discharge pump is to deliver the rated throughput of the centrifuge whenoperating against:

(1) A specified discharge pressure when pumping lubricating oils ofviscosities in the range of 18 mm2/s to 24 mm2/s (centistokes);

(2) A specified discharge pressure when pumping fuel oils of viscosities in therange 2 mm2/s to 14.5 mm2/s (centistokes).

e . Lubricating oil centrifuge discharge pumps are also to be capable of pumping oilof viscosities up to a maximum of 2000 mm2/s (centistokes) when starting up.

1.5 Motors

a . Motors are to be suitable for Class 1 protection in accordance withBS 4999 Part 111.

1.6 Oil Heater Performance

a . The heater is to be capable of heating the supply pump rated throughput of oilto a viscosity in the range of 18 mm2/s to 24 mm2/s (centistokes) with:

(1) An oil viscosity of 2000 mm2/s (centistokes) at inlet to the heater;

(2) A pressure drop through the heater not exceeding 0.5 bar.


1.3

1.7 Information Required from Manufacturer

a . The following information is to be provided by the centrifuge manufacturer:

(1) Curves on a base of pump total head ranging from specified manometricsuction lift to the pressure at which the integral supply pump relief valveis fully open showing:

(a) The output of the supply pump;

(b) The power input to the supply pump;

(2) A curve on a base of output showing the total head developed by thedischarge pump;

NOTE For lubricating oil centrifuges the curves are to be based on an oilviscosity of 18 mm2/s centistokes and a density of 0.87 g/ml. Forfuel oil centrifuges the curves are to be based on viscosities of2.0 mm2/s and 14.5 mm2/s (centistokes) and a density of0.84 g/ml.

(3) The time taken for the supply pump to prime a specified length of suctionpiping with oil at the maximum specified viscosity;

(4) The maximum and average particle sizes passed and the liquid and solidextraction efficiencies when handling oils containing 1% by weight of 700grade carborundum and 5% by volume of water;

(5) The time between start and achieving normal running speed;

(6) Balancing requirements:

(a) The limit of acceptable residual dynamic unbalance;

(b) The method used to measure residual dynamic unbalance;

(c) The method of correction used to bring the unbalance within theacceptable limit;

(7) The dry weight of:

(a) The entire centrifuge;

(b) Each interchangeable assembly in excess of 15 kg;

(c) The motor;

(d) The motor control gear;

(8) Weight of fluids in the unit at normal working level.


1.4

1.8 Installation

1.8.1 Centrifuges

a . Centrifuges are to be provided with save-alls, which will be supplied by theshipbuilder and fitted between the pedestal and the shock mounts.

b . The supporting surfaces of the ships seatings are to be finally machined to suitthe centrifuge feet after the seating has been permanently installed in the ship.

1.8.2 Lifting Gear

a . Lifting gear is to be provided by the centrifuge manufacturer. The centrifugeand its frame are to be moved only by using this lifting gear.

1.9 Testing

a . Testing is to adequately demonstrate the capability and safe operation of theequipment.

b . A list of Type Tests and Examinations and Production Tests will be issued bythe Defence Procurement Agency (DPA). The Type Test programme is to beconducted on one unit. All subsequent equipment is to be Production Tested toconfirm the performance of each assembly conforms to Type Tests results.

c . The equipment manufacturer is to produce a record of results in a form agreedby DPA.

d . All testing is to be conducted with the base of the centrifuge horizontal unlessdirected otherwise.

e . The oil used in tests is to be the same grade as the oil for which the centrifuge isspecified.

f . Water and solids removal performance tests are to be carried out with the testoil containing an inlet contamination of 1% by weight of suspended solids and5% by volume of water (see Clause 1.3b).

g . Samples from inlet and outlet oil connections are to be analysed for suspendedsolids by filtration and drying and for water by the Dean and Stark method toASTM D95.

h . Flow performance tests are to be carried out using test oil with a contaminationof 5% by volume of water.


2.1

2. NATIONAL/INTERNATIONAL REGULATIONS

Related Documents: LOLER 98; see also Annex A.

2.1 Lifting Operations

a . Lifting activities identified at Clause 1.8.2, are to conform to the legislativeregulations stated in Lifting Operations and Lifting Equipment Regulations1998 (LOLER 98).


2.2


3.1

3. MILITARY STANDARDS/REQUIREMENTSRelated Documents: BS 1134; BS 5500; DEF STAN 0035; DEF STAN 015;DEF STAN 0510; NES 302; NES 303; NES 320; NES 322; NES 324; NES 327;NES 329; NES 341; NES 345; NES 360; NES 362; NES 502; NES 514; NES 626:NES 627; NES 632; NES 722; NES 726; NES 748; NES 773; NES 1004; BR 3013(2);BR 3021(2); see also Annex A.

3.1 Lubrication

a . Requirements for any oils or greases to be used for any purpose, are whereverpossible to be selected from those listed in DEF STAN 01-5. If for any reasonthis is not possible it is to be brought to the attention of the DPA.

3.2 Drawings

a . All drawings and diagrams are to conform to the requirements of NES 722 andDEF STAN 05-10. Additional requirements are to be identified in theSystem Requirement Document (SRD).

3.3 Environmental Conditions

3.3.1 General

a . Centrifuges are to be capable of operating continuously under the conditionsstated in NES 1004 and DEF STAN 00-35. HM Surface Ships are to conform toInstallation Region Reference 3 and Submarines are to conform to InstallationRegion Reference 6 requirements unless otherwise directed by the SRD.

3.3.2 Vibrational Environment

a . Centrifuges are to be vibration tested in accordance with NES 1004 andDEF STAN 00-35 unless instructed otherwise by the SRD.

3.3.3 Noise and Vibration

a . Noise and vibration levels to satisfy ships signatures will be given in the SRD.Guidance and test requirements are stated in NES 1004 and DEF STAN 00-35.

3.3.4 Shock

a . The inherent shock strength of the equipment is to meet the requirementsspecified in the SRD and NES 1004.

3.4 Pumps

a . Pumps are to conform to the relevant requirements in NES 327.

b . A separate motor driven positive displacement type supply pump is preferredfor fuel systems (see NES 320).


3.2

3.5 Motors and Starters

a . Electric motors are to conform to the requirements of NES 627 and NES 632.

b . Starters are to conform to the requirements of NES 626.

3.6 Strainers

a . Strainers are to be selected from the preferred range detailed in NES 748.

3.7 Oil Heaters

a . Oil heaters are to conform to the requirements of NES 329.

3.8 Tanks

a . A sludge tank is to be provided by the shipbuilder as part of a selfcleaningcentrifuge installation (see NES 322).

3.9 Valves

a . Valves are to be selected from NES 360.

3.10 Pipework

a . Pipework is to be selected from BR 3013(2).

3.11 Flexible Connections

a . Flexible rubber pipe assemblies and bellows are to conform to NES 345.

3.12 Shock Mountings

a . Centrifuges are to be suitable for mounting on appropriate shock mountsselected from BR 3021(2).

3.13 Sampling Connections

a . Sampling points at the dirty oil inlet and the clean oil outlet are to be suppliedby the manufacturer. Each sampling point is to be fitted and orientated asshown in NES 320 and facilitate the use of the sampling kit detailed in the SRD.

3.14 Manufacturing Requirements

a . Welding standards are to conform to NES 773. Procedures for welding of highlystressed parts are to conform to BS 5500. Requirements for surface finishes areto conform to BS 1134.

3.15 Installation Requirements

3.15.1 Centrifuges

a . Space for operation and maintenance is to be provided in accordance withNES 302.

3.15.2 Electrical Connections

a . Requirements for the installation of electrotechnical equipment are given inNES 502. Cables are to be terminated at the equipment in accordance withNES 514.


3.3

3.15.3 Cleanliness

a . Grades of cleanliness for items, components and equipment are stated inNES 341.

b . Processes for cleaning and preservation during manufacture, storage andinstallation until final acceptance are given in NES 341.

c . Before any equipment is installed on board the compartment is to conform tothe requirements of NES 726.

3.15.4 Flushing

a . After assembly the system is to be flushed in accordance with the instructionsgiven in the parent system NES, i.e.:

(1) NES 303 Lubrication Oil Systems for Propulsion and Generation inHM Surface Ships and Submarines;

(2) NES 320 Fuel Systems for Gas Turbine and Diesel Engines in HM SurfaceShips;

(3) NES 324 Requirements for Hydraulic Systems.

3.16 Test Requirements

a . Tests are to conform to the requirements of NES 362, NES 1004 andDEF STAN 00-35. A list of tests to be conducted will be issued by DPA.


3.4


4.1

4. DESIGN REQUIREMENTS/GUIDANCERelated Documents: There are no related documents in this section.

4.1 Safety

a . All hazards are to be where possible avoided by design. Where this is notpossible one of several protective measures are to be taken. Any residual hazardis to be indicated by warning labels positioned adjacent to the hazard andincluded in the operating instructions.

4.2 General

a . Centrifuge design is to be such as to allow the maximum interval betweenroutine servicing.

b . Centrifuges are not required to operate fully immersed.

4.3 Pumps

a . Centrifuges are to be provided with:

(1) An integral or separate supply pump to deliver dirty oil to the centrifuge;

(2) A pump for discharging clean oil from the centrifuge;

(3) A paring-disc pump, when required, for discharging water fromself-cleaning type centrifuges.

b . A separate motor driven supply pump is required when the system thecentrifuge is serving:

(1) Demands a higher suction lift capability than is generally specified for anintegral supply pump (see Clause 1.4c.);

(2) Requires the pump to perform duties additional to that of a centrifugesupply pump.

c . The design is to ensure that the centrifuge discharge pump has a higherthroughput than the supply pump to preclude overflowing in any condition.

d . Arrangements are to be fitted whereby the rate of discharge of oil to thecentrifuge can be regulated. Surplus oil is to be returned to the supply pumpsuction unless there are particular reasons to return it to a tank. Thearrangements are to be such that the suction chamber of the centrifugedischarge pump cannot run dry. This requirement is particularly important forpositive displacement type pumps.

e . Each integral positive displacement type pump is to be fitted with aspring-loaded relief valve with return to suction. No valve is to be fittedbetween the pump and the relief valve or in the return to source. The reliefvalve is to be permanently set to prevent excessive discharge pressure in theevent of operating against a closed discharge valve in the system.

f . It is essential that the inlet connection of the centrifuge supply pump remainsprimed with oil, even where the pump is self priming. To achieve this anon-return valve is to be provided in the pump suction line.

g . When a paring-disc pump is provided to discharge clean oil from thecentrifuge, the discharge head is to be not less than 11 m at the ratedthroughput of the centrifuge and the appropriate viscosity.


4.2

4.4 Strainers

a . A strainer is to be fitted at the inlet branch of the centrifuge integral supplypump and is to be 80 mesh size.

4.5 Oil Heaters

a . Centrifuges, other than fuel centrifuges, are to be provided with an oil heater,which is mounted separately from the centrifuge. The origin of supply will bestated in the SRD.

4.6 Tanks

4.6.1 Anti-flood Tank

a . An antiflood tank is to be provided by the centrifuge manufacturer as anassociated part of a centrifuge to meet the requirements of Clause 4.9.1. Theantiflood tank is to protect against loss of oil in the event of water seal failure.Alternative automated systems for this application should be submitted to theDPA for consideration.

b . The tank is to be fitted with a float controlled switch, set to shut down thecentrifuge if the oil or water in the tank rises to a predetermined level andinitiate an alarm.

c . The relative positions of the antiflood tank and the sullage tank are to be suchthat the water collecting in the antiflood tank drains continuously to thesullage tank. The effluent drain hole from the antiflood tank is to be fitted witha normally open SHUTOFF cock or valve of sufficient diameter to allow normalflow to drain adequately. The SHUTOFF cock or valve should only be shutwhen testing the float switch/alarm and fully opened on completion.

4.6.2 Sludge Tank

a . The provision of a common sludge tank for numerous separators may beconsidered, see Clause 3.8.

4.6.3 Operating Water Tank

a . An operating water tank, of suitable capacity for a selfcleaning centrifuge, is tobe provided by the centrifuge manufacturer and installed by the shipbuilder.The location of the tank is to provide the centrifuge with the static headrequired.

b . The tank is to be fitted with an air vent and a float controlled inlet valve tomaintain the water level in the tank.


4.3

4.7 Flexible Connections

a . Centrifuges are to be connected to associated service systems by flexibleconnections.

b . Flexible hoses for bowl sealing and operating water supplies, where fitted directto the centrifuge, are to be provided by the centrifuge manufacturer. All otherflexible connections are to be supplied by the shipbuilder.

4.8 Pipework

a . Piping on centrifuges is to be ungalvanized mild steel. Sampling flanges are tobe manufactured in the same material as the pipework to which they areconnected.

b . Discharge pipework is to include a length of clear material to enable visualinspection of discharged fluids whilst in operation.

4.9 Control and Instrumentation

4.9.1 Control

a . Each centrifuge is to be provided with an automatic safety device to preventexcessive loss of oil from any cause by stopping the centrifuge motor.

b . If the automatic safety device is actuated by a signal from a pressure transducerin the centrifuge clean oil discharge, the centrifuge starter is to include aninhibit switch to allow the unit to be started.

c . Where individual belts drive the centrifuge bowl and the supply pump; the drivemotor control is to be arranged to stop the motor in the event of the bowl drivebelt breaking.

d . The centrifuge starter and control panel is to be located adjacent to thecentrifuge to permit local starting and stopping. Arrangements are to beprovided so that the centrifuge can be stopped from a remote position.

e . If a separate motor driven supply pump is installed the separate starters of thepump and the centrifuge are to be interconnected:

(1) To ensure that the centrifuge cannot run when the supply pump isstopped;

(2) So that the supply pump is stopped by the automatic safety device calledfor in Clause 4.9.1a;

(3) To inhibit the automatic safety device both when starting the pump andcentrifuge and when running the pump with the centrifuge stopped.


4.4

4.9.2 Instrumentation

a . Centrifuges are to be provided with pressure indicators with sensing points in:

(1) The centrifuge oil inlet;

(2) The clean oil discharge line.

b . Centrifuges, with integral supply pumps, are also to be provided with apressure/vacuum indicator with a sensing point in the inlet branch of the pump,where applicable.

c . Pressure indicators are to be supplied with an isolating valve at each sensingpoint.

d . Lubricating oil centrifuges are to be provided with a temperature indicator witha sensing point in the centrifuge supply from the heater. The pocket for thetemperature indicator sensor is to be seal welded.

e . Pressure and temperature indicators are to be mounted on a panel attached tothe centrifuge and located so that the indicators are clearly visible from theoperating position.


5.1

5. CORPORATE EXPERIENCE & KNOWLEDGE

This NES contains no Corporate Experience & Knowledge information.


5.2


ANNEX AA.1

ANNEX A

RELATED DOCUMENTS

A1. The following documents and publications are referred to in this NES:

LOLER 98 Lifting Operations and Lifting Equipment Regulations 1998

BS EN 292 Safety of Machinery, Basic Concepts, General Principles forDesign:Part 1: Basic Terminoligy, MethodologyPart 2: Technical Principles and Specifications

BS EN 10088 Stainless Steels:Part 1: List of Stainless Steels

BS EN 12547 Centrifuges. Common Safety Requirements

BS 1134 Assessment of Surface Texture

BS 4999 General Requirements for Rotating Electrical Machines:Part 111: Specification for Builtin Thermal Protection for

Electric Motors Rated at 660 Volts AC and Below

BS 5500 Specification for Unfired Fusion Welded Pressure Vessels

JSP 430 Ship Safety Management System Handbook:Volume 1: Policy and Guidance on MOD Ship and Equipment

Safety Management

DEF STAN 0035 Environmental Handbook for Defence Material

DEF STAN 015 Fuels, Lubricants and Associated Products

DEF STAN 0510 Drawing Procedure

NES 302

(DEF STAN 02-302 Pt 1)(DEF STAN 08-103 Pt 2)

Requirements for Maintenance Envelopes and Removal Routes:

Part 1: HM Surface ShipsPart 2: Requirements for Submarines

NES 303

(DEF STAN 02-303)

Lubricating Oil Systems for Propulsion and Generation in HMSurface Ships and Submarines

NES 320

(DEF STAN 07-220)

Requirements for Design and Installation of Fuel Systems for GasTurbines and Diesel Engines in Surface Ships

NES 322

(DEF STAN 02-322)

Oil Pollution Prevention Shipboard Arrangements

NES 324

(DEF STAN 02-324 Pt 1)

Requirements of Hydraulic Systems:

Part 1: General

NES 327

(DEF STAN 02-327)

Pumps and Eductors

NES 329

(DEF STAN 08-105)

Requirements for Heat Exchangers

NES 341

(DEF STAN 02-341)

Requirements for Cleaning of Items, Components and Equipmentfor Fluid Systems

NES 345

(DEF STAN 02-345)

Requirements for Flexible Rubber Pipe Assemblies and Bellows inUse in Systems from Vacuum to 10 bar


ANNEX A A.2

NES 360

(DEF STAN 02-360)

List of Preferred Standard Valves (Metric) (Low Pressure)

NES 362

(DEF STAN 02-362)

Type and Production Testing of Mechanical Equipment

NES 502

(DEF STAN 02-502)

Requirements for Electrical Installations

NES 514(DEF STAN 02-514)

Guide to Cable Entry, Termination and Junction Components forEquipment

NES 626

(DEF STAN 02-626)

Control and Surveillance Equipment for Plant and SystemInstallations

NES 627

(DEF STAN 02-627)

Requirements for General Application to Rotating ElectricalMachinery

NES 632(DEF STAN 07-244)

Requirements for ac and dc Motors

NES 722

(DEF STAN 02-722)

Requiremnts for the Preparation, Identification and Managementof Drawings

NES 726

(DEF STAN 02-726)

Requirements for Cleanliness of Ships During Build

NES 748

(DEF STAN 02-748)

Strainers, Preferred Range

NES 773

(DEF STAN 02-773)

Minimum Acceptance Standards for Welds in HM Surface Shipsand Submarines

NES 1004

(DEF STAN 08-104)

Requirements for Design and Testing of Equipments to MeetEnvironmental Conditions

BR 3013(2) Admiralty Pipework Standards (Metric)

BR 3021(2) Shock Manual (Metric)

ASTM D9599 American Society for Testing and MaterialsStandard Test Method for Water in Petroleum Products andBituminous Materials by Distillation


ANNEX BB.1

ANNEX B

ABBREVIATIONS AND DEFINITIONS

B1. For the purpose of this NES the following abbreviations apply.ASTM American Society of Testing and Materials

BR Book of Reference

BS British Standard

BS EN British Standard European

DEF STAN Defence Standard

DLO Defence Logistics Organisation

DPA Defence Procurement Agency

LOLER Lifting Operations and Lifting Equipment Regulations

MOD Ministry of Defence

NES Naval Engineering Standard

PD British Standards Institution Published Document

SRD System Requirement Document

B2. There are no definitions in this NES.


ANNEX B B.2


ANNEX CC.1

ANNEX C

PROCUREMENT CHECK LIST

Notes:

C.1 This Check List is to ensure that certain aspects of this Naval Engineering Standard are consulted when preparing a procurement specification for a particular applicationparticular application.

C.2 Clauses where a preference for an option is to be used or where specific data is to be added are included in the Check List.

C.3 Each item is to be marked either:

= included

NA = not applicable

CHECKNo

CHECK CLAUSE No or NA

1 NES 323 to be invoked in ProcurementSpecification.

Foreword

2 Systems medium in which Centrifuges are to befitted stated.

SCOPE

3 Centrifuge to be fully automatic in operation. 1.2

4 Performance specification for lubricatingoil/fuel Centrifuge adequate.

1.3

5 Performance specification for lubricatingoil/fuel pumps suitable.

1.4

6 Performance specification for lubricating oilheater adequate.

1.6

7 Sufficient information requested frommanufacturer.

1.7

8 Provision of suitable lifting gear. 1.8.2

9 Test requirements identified for fuel and/orlubricating oil Centrifuges.

1.9

10 Presentation of testing results. 1.9

11 Use of specified oils and greases. 3.1

12 Any additional drawings required. 3.2

13 Additional environmental restrictions. 3.3

14 Provision of a sludge tank. 3.8

15 Sampling kit identified. 3.13

16 Origin of oil heaters if required. 4.5

17 Supply and location of tanks. 4.6

18 Supply of flexible connections. 4.7

This Check List may be subject to revision after other related NES have been finalised.


ANNEX C C.2


INDEXINDEX 1

ALPHABETICAL INDEX

(Note: Page numbers are given)

AAnti Flood Tank, 4.2

Automatic Cleaning, 1.1

Automatic Safety Device, 4.3

CCables, 3.3

DDiagrams, 3.1

Discharge Pump, 1.2

EElectrical connections, 3.3

FFlushing, 3.3

GGrades of Cleanliness, 3.3

HHazards, 4.1

MManual Operation, 1.1

Manufacturing requirements, 3.2

Maximum duty condition, 1.1

Mesh Size, 4.2

NNoise, 1.2

OOils and Greases, 3.1

PParticle Size, 1.1

Pressure Sensors, 4.4

Pressure tests, 3.3

RRelief Valve, 4.1

SSampling connection, 3.2

Save-alls, 1.3

Seatings, 1.3

Servicing, 4.1

Shock mountings, 3.2

Sludge Tank, 3.2, 4.2

Suction Lift, 4.1

Supply Pump, 1.2

Surplus Oil, 4.1

TType Test, 1.3

VOil Heater, 1.2

Vibration, 3.1

Viscosity Range, 1.1

WWeight, 1.3


INDEX INDEX 2

Inside Rear Cover

Crown Copyright 2001

Copying Only as Agreed with DStan

Defence Standards are Published by and Obtainable from:

Defence Procurement AgencyAn Executive Agency of The Ministry of Defence

Directorate of StandardizationKentigern House65 Brown Street

GLASGOW G2 8EX

DStan Helpdesk

Tel 0141 224 2531/2 Fax 0141 224 2503

Internet e-mail [email protected]

File Reference

The DStan file reference relating to work on this standard is D/DStan/069/02/323

Contract Requirements

When Defence Standards are incorporated into contracts users are responsible for their correctapplication and for complying with contractual and statutory requirements. Compliance witha Defence Standard does not in itself confer immunity from legal obligations.

Revision of Defence Standards

Defence Standards are revised as necessary by up issue or amendment. It is important thatusers of Defence Standards should ascertain that they are in possession of the latest issue oramendment. Information on all Defence Standards is contained in Def Stan 00-00 Standardsfor Defence Part 3 , Index of Standards for Defence Procurement Section 4 Index of DefenceStandards and Defence Specifications published annually and supplemented regularly byStandards in Defence News (SID News). Any person who, when making use of a DefenceStandard encounters an inaccuracy or ambiguity is requested to notify the Directorate ofStandardization (DStan) without delay in order that the matter may be investigated andappropriate action taken.

CONTENTSTITLE PAGESCOPEFOREWORDSponsorshipConditions of ReleaseCategories of NESRelated DocumentsHealth and Safety

1. PERFORMANCE SPECIFICATION1.1 Safety1.2 Centrifuges1.3 Centrifuge Performance1.4 Pumping Equipment Performance1.5 Motors1.6 Oil Heater Performance1.7 Information Required from Manufacturer1.8 Installation1.8.1 Centrifuges1.8.2 Lifting Gear

1.9 Testing

2. NATIONAL/INTERNATIONAL REGULATIONS2.1 Lifting Operations

3. MILITARY STANDARDS/REQUIREMENTS3.1 Lubrication3.2 Drawings3.3 Environmental Conditions3.3.1 General3.3.2 Vibrational Environment3.3.3 Noise and Vibration3.3.4 Shock

3.4 Pumps3.5 Motors and Starters3.6 Strainers3.7 Oil Heaters3.8 Tanks3.9 Valves3.10 Pipework3.11 Flexible Connections3.12 Shock Mountings3.13 Sampling Connections3.14 Manufacturing Requirements3.15 Installation Requirements3.15.1 Centrifuges3.15.2 Electrical Connections3.15.3 Cleanliness3.15.4 Flushing

3.16 Test Requirements

4. DESIGN REQUIREMENTS/GUIDANCE4.1 Safety4.2 General4.3 Pumps4.4 Strainers4.5 Oil Heaters4.6 Tanks4.6.1 Anti-flood Tank4.6.2 Sludge Tank4.6.3 Operating Water Tank

4.7 Flexible Connections4.8 Pipework4.9 Control and Instrumentation4.9.1 Control4.9.2 Instrumentation

5. CORPORATE EXPERIENCE & KNOWLEDGEANNEX A RELATED DOCUMENTSANNEX B ABBREVIATIONS AND DEFINITIONSANNEX C PROCUREMENT CHECK LISTALPHABETICAL INDEX