nes 747 part 1 requirements for nickel aluminium bronze castings and ingots

Ministry of DefenceDefence Standard 02-747 (NES 747)

Issue 1 Publication Date 01 April 2000

Incorporating NES 747 Part 1 Category 2

Issue 4 Publication Date October 1999

Requirements For Nickel AluminiumBronze Castings And Ingots

Part 1Nickel Aluminium Bronze

Naval Alloy Centrifugally Cast

DStan

DStan is now the publishing authority for all Maritime Standards (formerly NESs). Any reference to any other publishing authority throughout this standard should be ignored. Any queries regarding this or any other Defence Standard should be referred to the DStan Helpdesk as detailed at the back of this document.

AMENDMENT RECORD

Amd No Date Text Affected Signature and Date

REVISION NOTE

This standard is raised to Issue 1 to update its content.

HISTORICAL RECORD

This standard supersedes the following:

Naval Engineering Standard (NES) 747 Part 1 Issue 4 dated October 1999.

Ministry of Defence

Naval Engineering Standard

CATEGORY 2

NES 747 Part 1 Issue 4 October 1999

REQUIREMENTS FOR NICKEL ALUMINIUM BRONZECASTINGS AND INGOTS

PART 1

NICKEL ALUMINIUM BRONZE NAVAL ALLOYCENTRIFUGALLY CAST

CROWN COPYRIGHT 1999

This NES Supersedes

NES 747 PART 1 ISSUE 1NES 747 PART 1 ISSUE 2NES 747 PART 1 ISSUE 3

Record of Amendments

AMDT INSERTED BY DATE

1

2

3

4

5

(i)

NAVAL ENGINEERING STANDARD 747

REQUIREMENTS FOR NICKEL ALUMINIUM BRONZE

CASTINGS AND INGOTS

PART 1 ISSUE 4 OCTOBER 1999

NICKEL ALUMINIUM BRONZE NAVAL ALLOY

CENTRIFUGALLY CAST

This Naval Engineering Standard

is authorized for use in MOD contracts

by the Defence Procurement Agency

and the Defence Logistics Organization

Published by:

Sea Technology Group,Defence Procurement Agency,STGSA,Ash 0, #95,MOD Abbey Wood,Bristol BS34 8JH

NES 747 Part 1Issue 4October 1999

(ii)

NES 747 Part 1Issue 4

October 1999

(iii)

SCOPE

1. This NES states the requirements for the physical characteristics, test methods andacceptance standards of centrifugally cast nickel aluminium bronze naval alloy from ingotsand approved certified scrap.


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October 1999

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FOREWORDSponsorship

1. This Naval Engineering Standard (NES) is sponsored by the Defence Procurement Agency,Ministry of Defence (MOD).

2. The complete NES 747 comprises:Requirements for Nickel Aluminium Bronze (NAB) Castings and IngotsPart 1: Nickel Aluminium Bronze Naval Alloy Centrifugally CastPart 2: Nickel Aluminium Bronze Naval Alloy Ingots and Sand Castings with

Welding Permitted to the Wetted SurfacePart 3: Nickel Aluminium Bronze Commercial Alloy Sand Castings and IngotsPart 4: Nickel Aluminium Bronze Naval Alloy Sand Castings with Welding

Restricted to the Non−Wetted Surface (Class I and II Castings only)Part 5: The Design andManufacture of Nickel Aluminium Bronze Sand Castings

3. 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.

4. If it is found to be unsuitable for any particular requirement MOD is to be informed inwritingof the circumstances.

5. No alteration is to be made to this NES except by the issue of an authorized amendment.6. Unless otherwise stated, reference in this NES to approval, approved, authorized and similar

terms, means by the MOD in writing.7. Any significant amendments that may be made to this NES at a later date will be indicated

by a vertical sideline. Deletions will be indicated by 000 appearing at the end of the lineinterval.

8. This NES has been reissued to reflect changes in Departmental Nomenclature due to theMOD reorganization and the changes in related documents.

Conditions of ReleaseGeneral

9. This Naval Engineering Standard (NES) has been devised solely for the use of the MOD, andits contractors in the execution of contracts for the MOD. To the extent permitted by law, theMOD hereby excludes all liability whatsoever and howsoever arising (including but withoutlimitation, libability resulting from negligence) for any loss or damage however caused whenthe NES is used for any other purpose.

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 publishedwithout written permissionof the MOD

11. The Crown reserves the right to amend or modify the contents of thisNES 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

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

13. When thisNES is used in connection with aMOD 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.


(vi)

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

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 Directorate of Standardization, Stan 1,Kentigern House, 65 Brown Street,Glasgow, G2 8EX.

c. Naval Engineering Standards CSE3a, CSE Llangennech, Llanelli, Dyfed,SA14 8YP.

d. Other documents Tender or Contract Sponsor to advise.

17. All applications to the MOD for related documents are to quote the relevant MOD Invitationto Tender or Contract number and date, together with the sponsoring Directorate and theTender or Contract Sponsor.

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

Health and Safety

Warning

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 in JSP430: MOD Ship Safety Management System Handbook.

Additional Information21. (There is no relevant information included.)


October 1999

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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). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Additional Information (vi). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CONTENTS (vii). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 1. PERFORMANCE SPECIFICATION 1.1. . . . . . . . . . .1.1 Classification 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.2 Physical Characteristics 1.1. . . . . . . . . . . . . . . . . . . . . . .1.2.1 Ingots 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.2.2 Ingot Analysis 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Table 1.1 Chemical Composition of Ingots 1.1. . . . . . . . . . . . . . . .1.2.3 Castings 1.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.2.4 Casting Analysis 1.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .Table 1.2 Chemical Composition of Castings 1.2. . . . . . . . . . . . . .1.2.5 Quality of Material 1.2. . . . . . . . . . . . . . . . . . . . . . . . . . .1.3 Mechanical Properties 1.3. . . . . . . . . . . . . . . . . . . . . . . .Table 1.3 Properties 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4 Defects and Rectification of Defects 1.3. . . . . . . . . . . . .1.4.1 Defects 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4.2 Rectification of Defects 1.3. . . . . . . . . . . . . . . . . . . . . . .1.4.3 Rectification of Dimensional Defects by

Weld Deposition 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4.4 Rectification of Surface Defects by Blending 1.4. . . . .1.4.5 Rectification of Surface and Sub-surface Defects

by Welding 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4.6 Limits of Combined Weld Repairs 1.4. . . . . . . . . . . . . .1.4.7 Impregnation 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4.8 Special Repairs 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5 Test Methods 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.1 Destructive Tests 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.1.1 Analysis 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.1.2 Mechanical Tests 1.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.1.3 Retests 1.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.2 Non-Destructive Tests 1.5. . . . . . . . . . . . . . . . . . . . . . . .1.5.2.1 Dimensional Check 1.5. . . . . . . . . . . . . . . . . . . . . . . . . . .


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1.5.2.2 Visual-Optical 1.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.2.3 Liquid-Penetrant 1.5. . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.2.4 Radiography/Ultrasonic Examination 1.5. . . . . . . . . . .1.5.2.5 Radiography 1.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5.2.6 Radiographic Examination of Non-Designated

Regions on a Sample Basis 1.6. . . . . . . . . . . . . . . . . . . .1.5.2.7 Ultrasonic Examination 1.6. . . . . . . . . . . . . . . . . . . . . . .1.5.2.8 Pressure Tests 1.6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 2. NATIONAL/INTERNATIONAL REGULATIONS 2.1

SECTION 3. MILITARY STANDARDS/REQUIREMENTS 3.1. . . .3.1 Acceptance Standards 3.1. . . . . . . . . . . . . . . . . . . . . . . .3.1.1 Destructive Examination Standards 3.1. . . . . . . . . . . . .3.1.1.1 Analysis 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.1.2 Mechanical Tests 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.1.3 Retests 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2 Non-Destructive Examination Standards 3.1. . . . . . . .3.1.2.1 Dimensional Check 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2.2 Visual-Optical 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2.3 Liquid-Penetrant 3.1. . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2.4 Radiography 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2.5 Ultrasonics 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2.6 Pressure Tests 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.2 Quality Assurance Documentation 3.2. . . . . . . . . . . . . .3.2.1 Ingots 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.2.2 Castings 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.3 Identification of Ingots and Castings 3.2. . . . . . . . . . . .3.3.1 Ingots 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.3.2 Castings 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.4 Packaging 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 4. DESIGN REQUIREMENTS/GUIDANCE 4.1. . . . . . .

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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


October 1999

1.1

1. PERFORMANCE SPECIFICATIONRelatedDocuments: BS 375, BS EN 1976, BS EN1978, BS 6208, BS EN 10002−1, DEFSTAN 03−1, NES 729 Parts 1, 4 & 5, NES 771, NES 863; see also Annex A.

1.1 Classification

a. The classification of castings is to be in accordance with NES 863.

1.2 Physical Characteristics

1.2.1 Ingots

a. For centrifugal casting stock is to be cast from virgin metals as follows:

(1) Nickel that complies with the chemical composition requirements ofBS 375: Grade R99.9.

(2) Iron that is of high purity, 99.5%w/wwith a carbon content not exceeding0.05% w/w.

NOTE ‘Swedish-Iron’ Nails have been found to meet the required purity.

(3) Aluminium commercial very pure, Grade 99.90% w/w.

(4) Copper that complies with either BS EN 1976 (designation Cu−ETP) orBS EN 1978 (designation Cu−CATH−2)

(5) Manganese − high purity electrolytic grade.

1.2.2 Ingot Analysis

a. Ingot Analysis is to conform to the chemical composition in Table 1.1.

ElementPer Cent By Weight

ElementNot Less Than Not More Than

Aluminium 8.9 9.6

Iron* 4.0 5.0

Nickel* 4.5 5.5

Manganese 1.0 1.4

Copper (by difference) Remainder

ImpuritiesZinc − 0.05

Lead − 0.01

Tin − 0.05

Silicon − 0.05

Magnesium − 0.05

Chromium − 0.01

Total Impurities − 0.20

*Nickel content is to be greater than the iron content.

Table 1.1 −Chemical Composition of Ingots


1.2

1.2.3 Castings

a. Castings are to be supplied in the ‘As Cast’ condition andmade from ingots andapproved scrap complying with the definition given in Annex B.

NOTE Contamination by graphite can be prevented by coating crucibles andladles with an alumina wash. The product Alumina Cement Pure Grade961, marketed by Morgan Matroc Ltd., Rugby, Warwickshire, orequivalent, has been found suitable.

All ingots used are to be stamped, embossed or have a label affixed witha unique cast number. Any ingots, on which the stamping or embossingis illegible, or the label has been removed/fallen off, or is illegible, are notto be used.

1.2.4 Casting Analysis

a. Casting Analysis is to conform to the chemical composition in Table 1.2.

ElementPer Cent By Weight

ElementNot Less Than Not More Than

Aluminium 8.9 9.5

Iron* 4.0 5.0

Nickel* 4.5 5.5

Manganese 0.75 1.3

Copper (by difference) Remainder

ImpuritiesZinc − 0.05

Lead − 0.01

Tin − 0.05

Silicon − 0.10

Magnesium − 0.05

Chromium − 0.01

Total Impurities − 0.25

*Nickel content is to be greater than the iron content.Table 1.2 −Chemical Composition of Castings

1.2.5 Quality of Material

a. Only the manufacturer’s own approved scrap complying with the definitiongiven in Annex B may be included in the cast. No other scrap is permitted.Following acceptance of the analysis from the melt no further additions arepermitted prior to pouring into the mould.


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1.3

1.3 Mechanical Properties

a. At room temperature the mechanical properties from nominated test pieces asspecified in Clause 1.5.1.2a. are to be as detailed in Table 1.3.

Tensile Strength 0.2% Proof StressElongation On

5.65Gauge Length

So

(N/mm2) (N/mm2) (Per Cent)600 230 15

Table 1.3 − Properties

1.4 Defects and Rectification of Defects

1.4.1 Defects

a. Any casting may be rejected for defects discovered during subsequentmachining notwithstanding that the casting had been passed previously asconforming to this NES.

1.4.2 Rectification of Defects

a. The rectification of surface and sub-surface defects by welding is not permittedon Class I and II centrifugal castings manufactured in accordance with thisNES.

b. Weld repair of Class III castings is to be in accordance with NES 771 and is tobe within the following limits of this NES.

1.4.3 Rectification of Dimensional Defects by Weld Deposition

a. Correction of casting dimensions, machining errors and repair of surfacedefects may be made by weld deposition using an approved procedure for thematerial concerned in accordance with NES 771 and is to be within thefollowing limits:

(1) Weld deposition thickness to be restricted to 20% of contract drawingsection thickness from 12mm to 50mm and to 10mmabove 50mm sectionthickness.

(2) Area of weld deposition in non-designated regions is to be restricted to20% of the non-wetted surface area of the region not including flangethickness and webs, subject to any limitations imposed by Clause 1.4.6a.

b. Weld build-up exceeding the tolerance on contract drawing section thickness isto be a reason for rejection.

NOTE Blending out of surface defects is preferable to weld repair wheneverpossible.


1.4

1.4.4 Rectification of Surface Defects by Blending

a. Unacceptable surface defects may be blended out by an approved process,providing the resulting depression does not reduce the contract drawing sectionthickness bymore than 5mm for section thickness over 50mm, or 10%of sectionthicknesses up to and including 50mm. The depression sides and ends are to besmoothly blended out by aminimum radius of three times the maximum depthof blending and the edge formed with the surface is also to be faired smooth. Theremaining section thickness in way of the depression is to be free fromsub-surface defects as revealed by radiography or ultrasonics, in Critical TestRegions and Test Regions. The total area subjected to blending, including thearea affected by the fairing, is not to exceed 10%of any designated region or 20%of any non-designated region.

b. Rectification by blending is not permitted where this encroaches on anybearingor sealing surface.

1.4.5 Rectification of Surface and Sub-surface Defects by Welding

a. Unacceptable surface defects which cannot be blended out within thelimitations of Clause 1.4.4a. and unacceptable sub-surface defects may berepaired by welding using an approved procedure for the material concerned inaccordance with NES 771 and within the following limits:

(1) Area of excavation in non-designated regions is to be restricted to 20% ofthe inner or outer surface area of the region, not including flangethicknesses and webs, subject to any limitations imposed by Clause1.4.6a.

1.4.6 Limits of Combined Weld Repairs

a. The total combined area of weld repairs from all causes, eg dimensionalcorrection, surface and sub-surface defects is to be within the following limits:

(1) The total weld repair area of class III castings is not to exceed 20% of thesurface area of the casting excluding flange thickness and webs.

1.4.7 Impregnation

a. Impregnation will not be accepted as a recovery procedure for Class I or IIcentrifugal castings. Impregnation is a recognized recovery procedure for ClassIII castings in accordance with Def Stan 03−1.

(1) Class III casting may be impregnated with the approval of the ProjectManager.

(2) The area of leakage necessitating remedial action does not exceed 10% ofthe total area pressure tested in non-designated regions in Class IIIcastings.

1.4.8 Special Repairs

a. Where the repairs necessary to meet the acceptance standards are moreextensive than are permitted by this specification and if it is considered thateffective economical repair is possible the Contractor may submit repairproposals in accordance with NES 771 to the Project Manager for decision.

1.5 Test Methods

1.5.1 Destructive Tests

1.5.1.1 Analysis

a. In addition to the normal melt control analysis, a full chemical analysis is to bemade from a sample piece taken from each cast for ingots and for castings.


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1.5

1.5.1.2 Mechanical Tests

a. Tensile tests inaccordance withBSEN10002−1 are to bemade ona test sampletaken from integrally cast material. The size, location and directionality of thetest pieces are to be agreed between the Project Manager and the founder.Threetensile-test specimens are advised, to enable retests in the event of failure of theinitial test specimen. Where the casting is of such a configuration that testpieces cannot be accommodated as an integral part of the casting, a separatelycentrifugally cast test piece from the same melt as the casting(s) it represents,is to be used for production of the cast test bars.

1.5.1.3 Retests

a. Should any of the original test specimens fail tomeet acceptance standards, twofurther specimens from the same test piece are to be broken in accordance withBS EN 10002−1.

1.5.2 Non-Destructive Tests

a. Reference diagrams according to NES 863 are to be provided by the purchaserfor all Class I and Class II castings to show Critical Test Regions and TestRegions which are to be subjected to non-destructive testing (NDT).

1.5.2.1 Dimensional Check

a. All castings are to be fully dimensionally checked.

1.5.2.2 Visual-Optical

a. All castings are to be 100% visually inspected, assisted where necessary by theuse of ¢5 magnification optics. All imperfections are to be identified andrecorded.

1.5.2.3 Liquid-Penetrant

a. It is recommended that a 100% liquid penetrant examination, in accordancewith NES 729 Part 4, is carried out on all Class I and Class II castings beforeany machining operations are commenced to prevent nugatory work.

b. Where practicable, a 100% liquid penetrant inspection is to be undertaken onall surfaces of Class I and Class II castings with the surfaces examined in theirfinished condition.

1.5.2.4 Radiography/Ultrasonic Examination

a. The manufacturer is to subject Critical Test Regions and Test Regions to either100% radiographic or 100% ultrasonic examination.

1.5.2.5 Radiography

a. Radiography is to be carried out in compliance with NES 729 Part 1. Allsub-surface imperfections are to be identified for subsequent assessment inaccordance with the acceptance standards.


1.6

1.5.2.6 Radiographic Examination of Non-Designated Regions on a Sample Basis

a. In certain circumstances examination by radiography on a sample basismay bespecified by contract or drawings to establish that a satisfactory general qualityof product is being supplied. Typical examples are:

(1) Lowly stressed Class II castings.

(2) Sample positions on large Class II or Class III castings.

(3) Batch supply of Class III castings.

1.5.2.7 Ultrasonic Examination

a. Ultrasonic examination is to be carried out in compliance with NES 729 Part 5.All sub-surface imperfections are to be identified for subsequent assessment inaccordance with the acceptance standards. Where ultrasonic examination isused the assessment of the casting is to be confirmed by radiography of selectedareas. A minimum of 10% of the total area examined by ultrasonics is to beradiographed.

NOTE The grain structure of cast nickel aluminium bronze may precludeinspection by ultrasonics. The suitability for ultrasonic inspection is to beassessed in accordance with BS 6208 Clauses 9.2 and 9.3.

1.5.2.8 Pressure Tests

a. When stated in the contract the castings are to be subjected to the specifiedwater-pressure test for a period of 15 minutes. Certain castings may requirelonger periods of pressure testing. When necessary this will be specified in thecontract.


October 1999

2.1

2. NATIONAL/INTERNATIONAL REGULATIONSThis NES contains no National/International Regulations information.


2.2


October 1999

3.1

3. MILITARY STANDARDS/REQUIREMENTSRelated Documents: NES 747 Part 1, NES 863 Part 1; see also Annex A.

3.1 Acceptance Standards

3.1.1 Destructive Examination Standards

3.1.1.1 Analysis

a. Each chemical analysis is to comply with:

(1) Table 1.1 for ingots.

(2) Table 1.2 for castings.

3.1.1.2 Mechanical Tests

a. Each tensile test result is to conform to Table 1.3 of this NES.

3.1.1.3 Retests

a. Both tensile test results are to conform to Table 1.3 of this NES.

3.1.2 Non-Destructive Examination Standards

3.1.2.1 Dimensional Check

a. Dimensions are to comply with the component drawing, and requirements ofNES 863.

3.1.2.2 Visual-Optical

a. On visual-optical inspection (Clause 1.5.2.2a.) the finished condition of allsurfaces is to be clean and free from cracks or linear defects. Rounded forms ofsurface defects are unacceptable in Critical Test Regions and Test Regions butmay be acceptable in Non-Designated Regions at the discretion of the ProjectManager.

NOTE Defects are deemed to be rounded when the aspect ratio of length to widthis 3:1 or less.

b. The surface finish is to meet the standard specified in the contract documentsand drawings.

3.1.2.3 Liquid-Penetrant

a. Indications of cracks, hot tears or chain-like porosity and surface oxideinclusions in linear formations are not acceptable.

b. Indications arising from porosity and surface oxide inclusions in non-linearformations are to be assessed as follows:

(1) Isolated pinpoint porosity (minimum separation 50mm) is acceptableexcept in areas where sealing of a housing against a running shaft isrequired, eg pump glands, propeller shaft seals etc, and in flexiblecouplings.

(2) Clustered pinpoint porosity and other defects are acceptable providedthat: The maximum size of any indication is not to exceed 3mm diameterbleed out and the sum of the diameters of all indications in an area of 70 ¢70mm does not exceed 24mm.


3.2

NOTE The indications identified in Clause 3.1.2.3b.(1) and 3.1.2.3b.(2) areacceptable providing that the immediate area of the castings is acceptablewhen examined for sub-surface defects.

c. There may be instances where machined surfaces of castings manufactured tothis NES require more stringent acceptance standards than those inClauses 3.1.2.3a. and 3.1.2.3b. eg in way of a wetted seal area. Where necessarythis requirement is to be clearly stated in the contract documents and is to bethe subject of discussion between the purchaser and the contractor prior tomanufacture of the castings.

3.1.2.4 Radiography

a. Cracks, hot tears and cold shuts are not acceptable in any area of the castings.Internal porosity and shrinkage are acceptable where;

(1) the local reduction in wall thickness does not exceed 5% of the designedwall thickness in Critical Test Regions and 10% in Test Regions,

(2) the total defective area does not exceed 10% of each Critical Test Regionand 20% of each Test Region containing the defect.

b. Where sample inspection is carried out in accordance with Clause 1.5.2.6a. thecumulative local reduction in section thickness resulting from sub-surfacedefects at any position is not to exceed 20% of the contract drawing sectionthickness. The total defective area is not to exceed 20% of the total area of thecasting examined.

3.1.2.5 Ultrasonics

a. Any defect that causes a signal greater than or equal to the signal produced bythe approved calibration standard is to be deemed unacceptable and the castingrejected. Where the backwall echo is attenuated by 40% or greater, theexamination by ultrasonics is unacceptable and radiography in accordance withClause 1.5.2.5a. is to be employed.

3.1.2.6 Pressure Tests

a. Each casting is to show no evidence of leakage.

3.2 Quality Assurance Documentation

3.2.1 Ingots

a. Each consignment of ingots is to be accompanied by Quality AssuranceDocumentation providing the results of themelt control analysis and the resultsof analysis of a sample piece taken from an ingot within the batch.

3.2.2 Castings

a. Each consignment of castings is to be accompanied by Quality AssuranceDocumentation giving the actual results of the tests required in Clause 1.5together with a certificate of compliance with the acceptance standards detailedin Clause 3.1.

3.3 Identification of Ingots and Castings

3.3.1 Ingots

a. Each ingot is to bemarked with the legend ‘NAB’ stamped or embossed in easilydiscernible letters. Each ingot is also to be marked with a unique cast numberwhich can be stamped or embossed in easily discernible letters, or an indeliblymarked self adhesive label is to be affixed; the unique cast number is topositively identify the ingot to its quality assurance documentation.


October 1999

3.3

3.3.2 Castings

a. Each casting is to be clearly identifiable during manufacture and bepermanently marked for identification during service life with the followingdetails:

(1) Pattern or Ship’s Identity Number plus NES 747 Part 1.

(2) Class of casting, ie CI, CII, CIII (see NES 863 Part 1).

(3) The legend ‘NAB−CC’.

(4) A unique cast Number that will relate the casting to its Quality AssuranceDocumentation.

b. The markings detailed in Clause 3.3.2a. are to be stamped, engraved orvibro-etched in the position indicated on the drawing. Markings are to be asconspicuous as the nature of the casting allows and provision is to be made fortransferring identification markings duringmanufacture such that traceabilityis maintained throughout the service life of a casting. The markings are not tobe made on the highly stressed regions, eg Critical Test Regions of the casting.

c. Where difficulty is experienced in satisfactorily applying identification symbols,this is to be resolved by consulting the Project Manager.

3.4 Packaging

a. Except where otherwise stated in the contract, packaging is to be in accordancewith the contractor’s normal practice subject to the affixing of a trade warninglabel and the addition of the following identification details on each package orcase:

(1) Description of castings.

(2) Quantity.

(3) Contract Number.


3.4


October 1999

4.1

4. DESIGN REQUIREMENTS/GUIDANCEThis NES contains no Design Requirements/Guidance information.


4.2


October 1999

5.1

5. CORPORATE EXPERIENCE & KNOWLEDGEThis NES contains no Corporate Experience & Knowledge information.


5.2


October 1999

A.1 ANNEX A

ANNEX A.

RELATED DOCUMENTS

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

BS 375 Specification for Refined Nickel

BS 6208 Method for Ultrasonic Testing of Ferritic Steel Castingsincluding Quality Levels

BS EN 1976 Copper and Copper Alloys. Cast Unwrought Copper Products

BS EN 1978 Copper and Copper Alloys. Copper Cathodes

BS EN 10002−1 Tensile Testing of Metallic MaterialsMethod of Test at Ambient Temperature

DEF STAN 03−1 Impregnation of Porous Castings

NES 729 Requirements for Non-Destructive Examination Methods:

Part 1: Radiographic

Part 4: Liquid Penetrant

Part 5: Ultrasonic

NES 771 Requirements Procedure and Inspection for Weld Repairs ofCopper Alloy and Nickel Alloy Castings

NES 863 Requirements for the Classification, Dimensions, Tolerances andGeneral Acceptance Standards for Copper and Nickel AlloyCastings


A.2ANNEX A


October 1999

B.1 ANNEX B

ANNEX B.

ABBREVIATIONS AND DEFINITIONS

B1. For the purpose of this NES the following abbreviations apply:

DPA Defence Procurement Agency

DLO Defence Logistics Organization

B2. For the purpose of this NES the following definitions apply:

Approved Scrap Scrap that is derived from nickel aluminium bronze, thecomposition of which has been established with regard tothe complete range of both the alloying elements andimpurity elements and is segregated and identifiable to thesatisfaction of the MOD/Acceptance Authority.

Cast A cast is:

the product of one furnace melt; or

the product of one crucible melt; or

the product of a number of furnaceor crucible melts where such areaggregated and mixed prior tosampling.

Centrifugal castings Centrifugal castings are made by introducing the alloy in amolten state into a mould which is rotated to ensure fillingand kept rotating while the alloy solidifies.

Contractor The Firm, Company, Organization or Establishmentworking within the scope of this NES.

Ingot A mass of metal of proportions to suit the Founder’srequirements.

Pinpoint porosity Any circular bleed out of less than 0.5mm diameter revealedduring liquid penetrant examination in accordance withNES 729 Part 4.

Project Manager The Section within the DPA or DLO, acting on behalf of theSecretary of State for Defence. The Project Manager shouldbe specified in the Contract, but where not known by thecontractor, enquiries are to be forwarded to DNA SectionNA115 Abbey Wood, Bristol. For sub−contractors, theProject Manager may be the Prime Contractor.

So The cross-section area of the gauge in a tensile testpiece,before testing, as detailed in BS EN 10002.


B.2ANNEX B


October 1999

C.1 ANNEX C

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 aparticular applicationparticular application.

C.2 Clauses where a preference for an option is to be used or where specific data isto 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 p or NA

1 Tensile test piece requirements. 1.5.1.2a.

2 Pressure tests 1.5.2.8a.

3 Radiography on a sample basis. 1.5.2.6a.

4 Surface finish requirements. 3.1.2.2b.

5 Isolated pinpoint porosity unacceptable. 3.1.2.3b.(1)

6 Liquid penetrant acceptance standards. 3.1.2.3c.

7 Packaging requirements. 3.4a.


C.2ANNEX C


October 1999

INDEX.1

ALPHABETICAL INDEX

(Note: Page numbers are given)

AAcceptance standards, 3.1

Alumina wash, 1.2

Analysis, 3.1

CCasting analysis, 1.2

Castings, 1.2

Chemical analysis, 3.1

Cold shuts, 3.2

Contamination by graphite, 1.2

DDefects, 1.3, 1.4, 3.1

Definitions, B.1

Destructive examination standards, 3.1

Destructive tests, 1.4

Dimensional check, 1.5, 3.1

EElongation, 1.3

IIdentification of castings, 3.3

Identification of ingots, 3.2

Impregnation, 1.4

Ingot analysis, 1.1

Ingots, 1.1, B.1

LLiquid penetrant, 1.5, 3.1

MManufacturer’s approved scrap, 1.2, B.1Mechanical properties, 1.3Mechanical tests, 1.5, 3.1

NNon−destructive examination standards, 3.1Non−destructive test, 1.5

OOptical inspection, 1.5, 3.1

PPhysical characteristics, 1.1Pinpoint porosity, 3.1Pressure tests, 1.6, 3.2Proof stress, 1.3

QQuality Assurance, 3.2, 3.3Quality of material, 1.2

RRadiography, 1.5, 1.6, 3.2Rectification of defects, 1.3Retest, 1.5, 3.1

TTensile strength, 1.3Tensile test, 1.5, 3.1Test pieces, 1.4, 1.5Tests, 1.4

UUltrasonics, 1.5, 1.6, 3.2

VVisual inspection, 1.5, 3.1


INDEX.2

Inside Rear Cover

© Crown Copyright 2000

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

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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/69/02/747.

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.

nes 747 part 1 requirements for nickel aluminium bronze castings and ingots

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