Ministry of Defence Defence Standard 02-864 (NES 864)

Issue 1 Publication Date 01 April 2000

Incorporating NES 864 Category 2

Issue 1 Publication Date September 1999

Carbon, Carbon-Manganese, AndChromium-Molybdenum Steel Pipes

And Tubes For Pressure Purposes

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) 864 Issue 1 dated September 1999.

Ministry of Defence

Naval Engineering Standard

CATEGORY 2

NES 864 Issue 1 September 1999

CARBON, CARBON − MANGANESE,AND CHROMIUM − MOLYBDENUM STEEL PIPES AND TUBES

FOR PRESSURE PURPOSES

CROWN COPYRIGHT 1999

This NES Supersedes

DGS 6142BDGS 6143DGS 8140D

Record of Amendments

AMDT INSERTED BY DATE

1

2

3

4

5

(i)

NAVAL ENGINEERING STANDARD 864

ISSUE 1 SEPTEMBER 1999

CARBON, CARBON −MANGANESE, AND CHROMIUM

MOLYBDENUM STEEL PIPES AND TUBES FOR PRESSURE PURPOSES

This Naval Engineering Standard is

authorized for use in MOD contracts

by the Defence Procurement Agency

and the Defence Logistics Organisation

Published by:

Sea Technology GroupDefence Procurement AgencyNA 145Ash 0, #95MOD Abbey WoodBristol BS34 8JH

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SCOPE

1. This NES specifies the requirements for the manufacture, inspection and testing ofcarbon, carbon−manganese and chromium molybdenum steel tubes for pressurepurposes. The normal application for such tubes is in steam and hydraulic systems.

2. The requirements specified in this NES cover tubes intended for use inFirst Level andnon First Level systems. Where tubes are required for use in First Level systems theadditional requirements of SSP 25 (as summarized in Annex E of this NES) must alsobe complied with.

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FOREWORD

Sponsorship

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

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

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. 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 Ministry of Defence 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 within this NES have been included with the permission ofthe British Standards Institution.

8. This NES has been issued to replace DGS 6142B, DGS 6143, and DGS 8140D, The technicalcontent has been updated to reflect current practice.

Conditions of Release

General

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 Process

12. This NES is the property of the Crown. Unless otherwise authorized in writing by the MODmust 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.

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.

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Categories of NES

15. 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 Documents

16. In the tender and procurement processes the related documents listed in each section andAnnex 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 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 calls for the use of processes, substances and/or procedures that may be 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. The manufacture and usage of steel tubes require careful attention to safety procedures inparticular high temperature operations and mechanical handling activities.

21. 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 Information(There is no relevant information included)

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CONTENTS

Page No

TITLE PAGE i. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SCOPE iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FOREWORD v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Introduction v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conditions of Release v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Categories of NES vi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Related Documents vi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Health and Safety vi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Warning vi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CONTENTS vii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 1. PERFORMANCE SPECIFICATION 1.1. . . . . . . .1.1 Steel Grade, Chemical Composition and

Mechanical Properties 1.1. . . . . . . . . . . . . . . . . . . . . .1.1.1 Steel Grade 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.1.2 Chemical Composition 1.1. . . . . . . . . . . . . . . . . . . . .1.1.2.1 Ladle Analysis 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . .Table 1.1 Chemical Composition 1.1. . . . . . . . . . . . . . . . . . . . .1.1.3 Product Analysis 1.2. . . . . . . . . . . . . . . . . . . . . . . . . .Table 1.2 Permitted Deviations of

the Product Analysis from theSpecified Ladle Analysis 1.2. . . . . . . . . . . . . . . . . . . .

1.1.4 Mechanical Properties 1.2. . . . . . . . . . . . . . . . . . . . . .Table 1.3 Mechanical Properties

at Room Temperature 1.3. . . . . . . . . . . . . . . . . . . . . .1.2 Manufacture 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.2.1 Steel Manufacture 1.3. . . . . . . . . . . . . . . . . . . . . . . . .1.2.1.1 Process 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.2.1.2 Deoxidation 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.2.2 Tube Manufacture 1.3. . . . . . . . . . . . . . . . . . . . . . . . .1.2.2.1 Process 1.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.2.3 Final Supply Condition 1.3. . . . . . . . . . . . . . . . . . . . .1.2.4 Heat Treatment 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . .1.3 Tube Dimensions and Tolerances 1.4. . . . . . . . . . . . .1.3.1 General 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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1.3.2 Order or Contract Requirements 1.4. . . . . . . . . . . . .1.3.3 Outside Diameter and Wall Thickness 1.4. . . . . . . .1.3.4 Length 1.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.3.5 Straightness 1.5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4 Test Methods and Examinations 1.5. . . . . . . . . . . . . .1.4.1 Non−Destructive Tests and Examination 1.5. . . . . . .1.4.1.1 Visual Inspections 1.5. . . . . . . . . . . . . . . . . . . . . . . . .1.4.1.2 Dimensional Inspections 1.5. . . . . . . . . . . . . . . . . . . .1.4.1.3 Ultrasonic inspection 1.5. . . . . . . . . . . . . . . . . . . . . . .1.4.1.4 Pressure Test 1.6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4.2 Destructive Tests, Standards and

Examinations 1.6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4.2.1 Mechanical Tests − Sampling 1.6. . . . . . . . . . . . . . . .1.4.2.2 Tensile tests at Room Temperature 1.6. . . . . . . . . . .1.4.2.3 Tensile Test at Elevated Temperature 1.7. . . . . . . . .1.4.2.4 Flattening or Bend Test 1.7. . . . . . . . . . . . . . . . . . . . .1.4.2.4.1 Flattening Test Method 1.7. . . . . . . . . . . . . . . . . . . . .1.4.2.4.2 Bend Test method 1.8. . . . . . . . . . . . . . . . . . . . . . . . . .1.4.3 Re−tests 1.8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 2. NATIONAL/INTERNATIONALREGULATIONS 2.1. . . . . . . . . . . . . . . . . . . . . . . . . .

SECTION 3. MILITARY STANDARDS/REQUIREMENTS 3.13.1 Acceptance Standards 3.1. . . . . . . . . . . . . . . . . . . . . .3.1.1 Non−Destructive Tests 3.1. . . . . . . . . . . . . . . . . . . . . .3.1.1.1 Visual Examination 3.1. . . . . . . . . . . . . . . . . . . . . . . .3.1.1.2 Dimensional Checks 3.1. . . . . . . . . . . . . . . . . . . . . . . .3.1.1.3 Ultrasonic Inspection 3.1. . . . . . . . . . . . . . . . . . . . . . .3.1.1.4 Pressure Tests 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.1.5 Eddy Current Tests 3.2. . . . . . . . . . . . . . . . . . . . . . . .3.1.2 Destructive Tests 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2.1 Tensile Tests at Room Temperature 3.2. . . . . . . . . . .3.1.2.2 Tensile Tests at Elevated Temperature 3.2. . . . . . . . .Table 3.1 Minimum Elevated Temperature Properties 3.2. . .3.1.2.3 Flattening Test 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.2.4 Bend Test 3.2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.3 Re−Tests 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.2 Quality Assurance Documentation 3.3. . . . . . . . . . .3.2.1 Test Certificate 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . .3.2.2 Certificate of Conformity 3.3. . . . . . . . . . . . . . . . . . .3.2.3 Records 3.3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.2.4 First Level Quality Assured Tubes 3.4. . . . . . . . . . . .3.3 Identification 3.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.4 Packaging 3.4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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

SECTION 5. CORPORATE EXPERIENCE ANDKNOWLEDGE 5.1. . . . . . . . . . . . . . . . . . . . . . . . . . .

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

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

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

ANNEX D. PROCEDURE FOR VERIFICATIONOF ELEVATED TEMPERATUREPROPERTIES D.1. . . . . . . . . . . . . . . . . . . . . . . . . . .

ANNEX E. INTERPRETATION OF SSP 25 E.1. . . . . . . . . . . .REQUIREMENTS APPLYING TO STEELTUBES INTENDED FOR USE IN FIRSTLEVEL SYSTEMS

Alphabetical Index Index 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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1. PERFORMANCE SPECIFICATIONRelated Documents: BS EN 10002−1, BS EN 10002−5, BS 3600, BS3602 Part 1, BS3604 Part 1, BS 3920 Part 1, see also Annex A.

1.1 Steel Grade, Chemical Composition and Mechanical Properties

1.1.1 Steel Grade

a. Four grades of steel tube are specified in this NES. details are provided below.The steels align with those specified in BS 3602 Part 1 and BS 3604 Part 1, andare to replace the original DGS grades which are now withdrawn. This NESpermits only the use of CFS grade tubes.

Steel Grade Steel Type Original DGS Grade BS No.

CFS 360 Carbon DGS 6142B: Carbon steelsteam piping

BS 3602 Part 1

CFS 430 Carbon−Manganese DGS 6142B: Carbon−manganese steelsteam piping

BS 3602 Part 1

CFS 500 Nb Carbon−Manganese DGS 8140D: Carbon−manganese steelhydraulic piping

BS 3602 Part 1

CFS 620 Chromium−Molyb-denum

DGS 6143: Chromium−Molyb-denum steel steam piping

BS 3604 Part 1

1.1.2 Chemical Composition

1.1.2.1 Ladle Analysis

a. The chemical composition of the steel grades based on ladle analysis is tocomply with the limits specified in Table 1.1.

SteelGrade Steel Type Composition (Weight %)

C Si Mn S P Cr Mo Nb A1

Min Max Min Max Min Max Max Max Min Max Min Max Min Max Max

CFS360

Carbon − 0.17 0.10 0.35 0.30 0.80 0.035 0.035 − − − − − − 0.06total

CFS430

CarbonManganese

− 0.21 0.10 0.35 0.40 1.20 0.035 0.035 − − − − − − 0.06total

CFS500 Nb

CarbonManganese

− 0.22 0.15 0.35 1.00 1.50 0.030 0.035 − − − − 0.015 0.10 0.06Total

CFS620

ChromiumMolybdenum

0.10 0.15 0.10 0.35 0.40 0.70 0.040 0.040 0.70 1.10 0.45 0.65 − − 0.02Metallic

Table 1.1: Chemical CompositionNOTES:

1. The symbol “−” denotes that the composition is not specified.

2. For all steel grades the residual elements are not to be greater than the following limits:

Tin 0.03% max.

Copper 0.25% max

Nickel 0.30% max.

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1.1.3 Product Analysis

a. If the Contract requires a product analysis to be carried out for acceptancepurposes, the composition is to be in accordance with the ladle analysis statedin Table 1.1, taking into account the permitted deviations stated in Table 1.2.

b. One sample is to be taken from each cast. The sample is to be taken either fromthe test piece used for verification of the mechanical properties or from thewhole thickness of the tube at a location immediately adjacent to that of themechanical test piece.

Element

Upper limit of rangein which the specifiedmaximum for ladle

l i f ll

Permitted deviations fromspecified limits*

%analysis falls

%Greater thanMaximum

Less thanMinimum

Carbon ! 0.25 0.03 0.03

Silicon ! 1.00 0.05 0.05

Manganese ! 2.0 0.10 0.10

Sulphur ! 0.050 0.005 −

Phosphorous ! 0.050 0.005 −

Chromium ! 10.0 0.10 0.10

Molybdenum > 0.35 0.05 0.05

! 1.5

Nickel ! 5.0 0.07 0.07

Copper ! 1.00 0.05 0.05

Niobium ! 0.05 0.005 0.005

Aluminium ! 0.06 0.005 0.005

* The deviations apply either above the specified maximum or below the specified minimumbut both deviations are not to be applied to different samples from the same cast.

Table 1.2: Permitted Deviations of the Product AnalysisFrom the Specified Ladle Analysis

1.1.4 Mechanical Properties

a. The mechanical properties at room temperature for the steel grades are tocomply with the requirements specified in Table 1.3.

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MECHANICAL PROPERTIES AT ROOMTEMPERATURE

SteelGrade

Steel TypeTensile Strength

(N/mm2)Yield Strength (N/mm2)

(Min)Elong5.65"SoGrade

Min Max Thickness Range (mm) %Mi!16 >16 !40 >40 !65 Min

CFS 360 Carbon 360 500 235 225 215 25

CFS 430 Carbon−Manganese

430 570 275 265 255 22

CFS 500Nb

Carbon−Manganese

500 650 355 345 335 21

CFS 620 Chromium−Molybdenum

440 590 290 (Min)max wall thickness of 25mm

22

Table 1.3: Mechanical Properties at Room Temperature

1.2 Manufacture

1.2.1 Steel Manufacture

1.2.1.1 Process

a. The steels are to be produced by an electric process or one of the basic oxygenprocesses.

1.2.1.2 Deoxidation

a. All steels are to be produced in the fully killed condition.

1.2.2 Tube Manufacture

1.2.2.1 Process

a. All tubes are to be produced by a seamless process and are to be cold finished(CFS grades).

1.2.3 Final Supply Condition

a. On completion of manufacture by the CFS process, tubes are to be heat treatedand supplied in the following conditions.

Steel Grade Final Supply Condition

CFS 360 NormalisedCFS 430 NormalisedCFS 500Nb NormalisedCFS 620 Normalised and Tempered

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1.2.4 Heat Treatment

a. Temperatures for heat treatment are to be within the following temperatureranges:

CFS 360 − Normalised in the temperatures range 880 to 940° C.

CFS 430 − Normalised in the temperatures range 880 to 940° C.

CFS 500 Nb − Normalised in the temperature range 900 to 960° C.

CFS 620 − Normalised in the temperature range 900 to 960° C andTempered in the range 640 to 720° C.

where temperatures are metal temperatures.

b. Heat treatment may be undertaken by either continuous furnaces or by batchtype furnaces.

c. If required, the supplier is to be able to demonstrate by appropriate records thata compliant heat treatment cycle has been achieved.

1.3 Tube Dimensions and Tolerances

1.3.1 General

a. Tubes are to be produced to specified dimensions for outside diameter andthickness. Where practicable, they are to comply with the dimensionalspecifications given in BS 3600. Permitted tolerances on dimensions arespecified in Section 1.3.3 below.

1.3.2 Order or Contract Requirements

a. If the Contract specifies tube dimensions and/or tolerances outside thosespecified in this NES, then, after agreement with the supplier, the dimensionsspecified in the Contract are to apply.

1.3.3 Outside Diameter and Wall Thickness

a. The tolerances on outside diameter are to include ovality and those on wallthickness are to include eccentricity (where ovality and eccentricity are asdefined in Annex B).

b. The following tolerances on outside diameter and thickness are to apply:

Outside diameter − # 0.75% with a minimum of # 0.50 mm

Thickness − # 7.5%

1.3.4 Length

a. Tubes may be supplied in random lengths. If the contract requires supply ofexact cut lengths, the permissible deviation on length is to be +6 mm −0 mmfor lengths up to 6.0 metres. For every 3.0 metres increase in length above 6.0metres, the plus tolerance is to be increased by 1.5mm up to amaximum of 12.0mm.

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1.3.5 Straightness

a . The tubes are not to deviate from straightness by more than 1 in 600 at thecentre of the length.

1.4 Test Methods and Examinations

1.4.1 Non−Destructive Tests and Examination

1.4.1.1 Visual Inspections

a. Visual inspection is to be carried out on the external and internal surfaces ofevery tube. For internal visual examination, the tube is to be viewed from eachend, recognising that the ability to visually examine the inner surface from thetube ends is limited in the case of small diameter tubes.

b. Visual inspection is to be carried out in suitable lighting, (ie an illuminance of500 lux or greater).

c. The tubes are to have a finish and surface condition which permits surfaceimperfections or marks requiring removal to be identified.

1.4.1.2 Dimensional Inspections

a. Each tube is to be subjected to the following dimensionsional checks:

(1) External diameter.

(2) Wall thickness.

(3) Ovality.

(4) Eccentricity of bore.

(5) Length.

(6) Straightness.

a. Dimensional checks are to be carried out using instruments and equipmentwhich are to calibrated and which are appropriate for the tube dimensions.

1.4.1.3 Ultrasonic inspection

a . Tubes procured for general purpose (non−First Level) use, ordered to BS3602(test category 2) or BS3604 (test category 2), do not require ultrasonicinspection where the pressure test specified in Section 1.4.1.4 has been carriedout.

b . Tubes procured for use in First Level applications shall be ultrasonically testedin accordance with Appendix F of BS3602 or BS3604 as applicable.

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1.4.1.4 Pressure Test

a. All tubes above 180 mm o.d. are to be subjected to a pressure test for assessingleak tightness. This test is to be a hydraulic pressure test using appropriateequipment. The test pressure for each tube is to be derived from the followingequation:

Test pressure P (bar) = 20 SaD

where: “D” is the specified outside diameter of the tube (mm)“a” is the specified wall thickness of the tube (mm)“S” is the stress (N/mm2) − which is to be taken as 80% of thespecified minimum yield strength of the tube material at roomtemperature.

b. The pressure test specified in Clause 1.4.1.4a is to be carried out at the pressureP or at 140 bar whichever is lower, but when 140 bar is lower than P the testshould be carried out at a pressure higher than 140 bar but not greater than thevalue of P determined from the equation.

c. For tubes below 180 mm o.d., the test may be either a hydraulic test inaccordance withClauses 1.4.1.4a &b or an eddy current test in accordance withthe requirements of BS 3602 Part 1.

1.4.2 Destructive Tests, Standards and Examinations

1.4.2.1 Mechanical Tests − Sampling

a. It is a requirement of this NES that sampling of tubes for performance ofdestructive testing be carried out on basis of the batch size in which the tubeswere manufactured.

b. This NES requires a defined percentage of the total tubes from each batch tobe subject to destructive testing, but if this calculated number of tests includea fraction, the number of tubes tested is to be rounded up to the next wholenumber.

c. The number of tubes on which mechanical tests are to be performed is to be asfollows:

Grade CFS 360

(1) Up to and including 323.9 mm outside diameter: 0.5% of the tubes fromeach batch.

(2) Over 323.9 mm outside diameter: 1% of the tubes from each batch.

Grade CFS 430, CFS 620 and CFS 500Nb

2% of the tubes from each batch.

d. The test samples are to be cut from the tube in the final heat treatmentcondition.

1.4.2.2 Tensile Tests at Room Temperature

a. From the above test sample from each tube selected for testing, one tensile testis to be prepared.

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b. The geometry and dimensions of the tensile test are to comply with therequirements of BS EN 10002−1.

c. The yield strength, tensile strength and elongation values are to be measured.For the yield strength, either the upper yield stress or the 0.5% proof stress isto be determined. The percentage elongation is to be reported with referenceto a gauge length of 5.65 "So, where So is the original cross sectional area of thegauge length.

1.4.2.3 Tensile Test at Elevated Temperature

a. If the contract requires elevated temperature proof stress testing to be carriedout for verification purposes, one test is to be made on each cast, using a testpiece taken at a position adjacent to the test piece used for the tensile test atroom temperature. The test is to be carried out in accordance with BSEN10002−5. If tubes of more than one thickness are to be supplied from onecast, the test piece is to be taken from a tube with the nominally thickestdimensions. The temperature of testing is to be specified, to the nearest 50° C,to the maximum service temperature (see Table 3.1).

b. Where the Contract Order does not specify that verification of elevatedtemperature proof stress values is to be carried out by testing, themanufactureris required to demonstrate the compliance of the tube steel with the minimumelevated temperature proof stress values, by the procedures specified inBS 3920 Part 1 (see Annex D of this NES).

1.4.2.4 Flattening or Bend Test

a. At the option of the manufacturer or as required by the contract, anddependent upon the dimensions of the tube, either a flattening test or a bendtest is to be carried out.

1.4.2.4.1 Flattening Test Method

a. For the flattening test, a ring not less than 40 mm long is to be taken from oneend of each selected tube.

b. The test piece is to be flattened at room temperature between parallel flatplatens until the distance between the platens H (mm) measured under load isnot greater than the value given by the equation:

H =(1 + C) a

C + aD

where a is the specified thickness (mm)D is the specified outside diameter (mm)C is the flattening constant(C = 0.09 for CFS 360, C = 0.08 for CFS 430, C = 0.07 for CFS 620,C=0.06 for CFS 500 Nb)

NES 864Issue 1April 1999

1.8

1.4.2.4.2 Bend Test Method

a. The test piece is to be cut circumferentially from one end of each selected tube.The test piece is not to be less than 40 mm wide and of the full thickness of thetube. For tubes greater than 20 mm thick, the test piece is to be machined froma circumferential strip to a rectangular cross section 40 mm by 20 mm. Thelength of the test piece is to be selected by the tube manufacturer, to suit theequipment in which the test is to be carried out.

b. The test piece is to be bent at room temperature in the direction of the originaltube curvature, through an angle of 180° , around a former having a diameter4 x test piece thickness (maximum).

1.4.3 Re−tests

a. Should a tube selected for testing fail any of the tests specified in Sections1.4.2.1 and 1.4.2.4 to the Acceptance Standards specified in Section 3, the tubeand the batch of tubes that it represents is to be deemed not to comply with thisNES unless:

(1) Two further tests of the same kind as produced the failure are made fromthe same tube and both these further tests prove satisfactory.

or

(2) The first tube tested is rejected and all the tests specified in Sections1.4.2.1 and 1.4.2.4 are carried out on two further tubes from the batchand all these tests are satisfactory.

or

(3) If either of the further tests required by (1) or(2) proves unsatisfactory,the tubes represented are suitably re−heat treated and samples selectedand tested in accordance with all the tests specified in Sections 1.4.2.1 to1.4.2.4 and all these tests are satisfactory to the Acceptance Standardsspecified in Section 3.

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February 1999

RESTRICTED −COMMERCIAL

2.1RESTRICTED −COMMERCIAL

2. NATIONAL/INTERNATIONAL REGULATIONS(No relevant information included)

NES 864Issue 1February 1999

RESTRICTED −COMMERCIAL

2.2RESTRICTED −COMMERCIAL

NES 864Issue 1

September 1999

3.1

3. MILITARY STANDARDS/REQUIREMENTSRelated Documents: BS 3602, BS 3604, BS 5383, SSP25, see also Annex A.

3.1 Acceptance Standards

3.1.1 Non−Destructive Tests

3.1.1.1 Visual Examination

a . Every tube is to be free of such defects as can be established by visualexamination.

b. The limit to the dressing of surface defects by grinding, is such that thethickness of the tube after dressing does not fall below the nominal thicknessby more than the thickness tolerance specified in Clause 1.3.3b.

c. It is permissible to dress by grinding or machining, surface marks andimperfections such as scabs, tears, laps, slivers or gouges. All dressed areas arerequired to blend smoothly into the contour of the tube.

d. The manufacturer is required to demonstrate that he has explored by grinding,a sufficient number of any surface marks and imperfections identified duringvisual inspection, to provide assurance that these imperfections have beenevaluated.

e. Surface imperfections which encroach upon the minimum wall thickness areto be considered as defects and are to be deemed not to comply with therequirements of this standard (Clause 1.3.3b).

f. The manufacturer is (subject to the limitations given in Clause 3.1.1.1g)required to dress:

(1) Surface imperfections found by exploration in accordance with Clause4.1.1g to be deeper than 5% of the nominal wall thickness or 1.5 mm,whichever is the lesser, but not less than 0.5 mm.

(2) Mechanical marks, abrasions or pits caused by themanufacturing processwhich are deeper than 1.6 mm.

g. If surface imperfections acceptable under Clause 3.1.1.1b are not scattered andappear over a large area in excess of what is considered to be an acceptablesurface condition, then tubes are to be rejected.

h. The tube ends are to be cut nominally square with the axis of the tube and areto be free from excessive burrs.

3.1.1.2 Dimensional Checks

a. The cold finished seamless tubes are to comply with the tolerances given inClauses 1.3.3a and b.

b. The tubes are to be supplied in accordance with Clause 1.3.4a.

3.1.1.3 Ultrasonic Inspection

a . When inspected in accordance with Clause 1.4.1.3b, the results are to beassessed in accordance with Appendix F of BS 3602 or BS 3604 as applicable.

NES 864Issue 1September 1999

3.2

3.1.1.4 Pressure Tests

a. When tested in accordance with Clauses 1.4.1.4a and b, the test pressure is tobe maintained sufficiently long for any leakage to be observed visually. Anytube failing to withstand the hydraulic pressure test is to be deemed not tocomply with the standard.

3.1.1.5 Eddy Current Tests

a. For tubes which are leak tested by eddy current tests in accordance withClause1.4.1.4c, the acceptance standard of the test is to be in compliance with BS 3602Part 1.

3.1.2 Destructive Tests3.1.2.1 Tensile Tests at Room Temperature

a. The mechanical properties at room temperature as determined by theprocedures specified in Clauses 1.4.2.2a to 1.4.2.2c, are to comply with therequirements of Table 3.1.

3.1.2.2 Tensile Test at Elevated Temperature

a. The elevated temperature minimum 0.2% proof stress values are to be asspecified in Table 1.4 when sampled and tested in accordance with Clause1.4.2.3a.

SteelG d

Minimum 0.2% Proof Stress Values (N/mm2) at Elevated TemperatureGrade ° C

20° 50° 100° 150° 200° 250° 300° 350° 400° 450° 500° 550°

CFS 360 212 207 198 187 170 150 132 120 112 108 − −

CFS 430 255 248 239 224 202 180 164 151 143 137 − −

CFS500Nb

343 333 313 291 267 244 222 203 188 177 − −

CFS 620 287 276 264 253 245 236 192 182 174 168 166 163

NOTE: Values at 20° C and 50° C are for information purposes only and are not subjectto verification.

Table 3.1: Minimum Elevated Temperature Properties

3.1.2.3 Flattening Test

a. When tested in accordance with procedures given in Clauses 1.4.2.4.1a & b, thering is to withstand being flattened to the specified limits without showing anycracks or flaws in the steel, except as permitted by Clause 3.1.2.3b.

b. The flattening test is carried out without preparation of the cut edges and anycracks originating at the edges of the test piece which are less than 6 mm longand which do not penetrate the thickness, are to be deemed acceptable to thisNES.

3.1.2.4 Bend Test

a. When tested in accordance with procedures given in Clauses 1.4.2.4.2a & b, thetest piece is not to show any crack or flaw, except as permitted by Clause3.1.2.4b.

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3.3

b. The bend test is carried out without preparation of the cut edges and any cracksoriginating at the edges of the test piece which are less than 6 mm long andwhich do not penetrate the thickness, are to be deemed acceptable to thisstandard.

3.1.3 Re−Tests

a. If re−tests are necessary the requirements of Clause 1.4.3a are to be met foracceptance.

3.2 Quality Assurance Documentation

3.2.1 Test Certificate

a. The manufacturer is to supply a test certificate with the following information:

(1) The MOD contract number.

(2) The steel grade (see Clause 1.1.1a).

(3) The steelmaking process.

(4) The steel cast identity

(5) The ladle analysis for elements specified in Table 1.1 for each of the castsused.

(6) The product analysis

(7) The mechanical test results for each of the batches tested.

(8) The heat treatment temperature and time and temperature for eachbatch of tubes.

(9) The results of the ultrasonic examination (where required).

(10) The pressure applied in the hydraulic leak tightness test.

(11) The elevated temperature test results or statement of verification ofvalues.

b. Where tubes are intended for use in First Level systems, the Test Certificatemust contain the information required by SSP25 (see Annex E of this NES), inaddition to the information called for in 3.2.1a.

3.2.2 Certificate of Conformity

a. The manufacturer is to supply a Certificate of Conformity on completion of thecontract. This certificate is to certify that all requirements specified in theContract have been complied with.

3.2.3 Records

a. The manufacturer is required to keep records of all activities which collectivelyform control of the tube manufacturing and certification procedures. Suchrecords are to be retained for possible future reference for a minimum periodof 5 years.

NES 864Issue 1September 1999

3.4

3.2.4 First level Quality Assured Tubes

a. Where tubes are specified for use in First level systems, the requirements ofSSP25 and any SOQRmust bemet in addition to the requirements of thisNES.

b. Guidance on the interpretation of SSP25 Quality Assurance requirements asapplied to steel tubes is included in Annex E.

3.3 Identification

a. Before dispatch from the manufacturer’s works, the tubes are to be marked incompliance with Clauses 3.3b & e.

b. Each tube is to be legibly marked at one end, commencing not more than300 mm from the end, by stencilling or other indelible marking.

The marking is to consist of the following in the sequence indicated and hardstamped, where possible on the cut end face:

(1) The manufacturer’s name or identification mark.

(2) The tube grade as defined in Clause 1.1.1a.

(3) NES 864 and designation ie outside diameter and wall thickness.

(4) The MOD Contract Order number.

(5) NATO Stock No.

(6) The steel cast identity.(Where the tube wall thickness does not permit hard stamping, theinformation is to be recorded on the tube surface by stencilling)

c. For tubes that are supplied bundled, the information in (1)−(6) of Clause 3.3bmay be stamped on one or more metal tags, or printed on banding clips orstraps, which are to be securely attached to each bundle, for additionalidentification during storage. However the individual tubemarking as specifiedin Clause 3.3b must also be applied. Not more than one steel grade is to beincluded in any one bundle.

d. The quality of the paint or ink is to be such that it will have a life of at least oneyear inunheated storage under cover. The dried film isnot to containmore than250 ppmof any of the followingmetals: lead, tin, copper, zinc. In addition, whenspecified in the Contract Order, the paint film is required to comply with anyspecified limits of sulphur and halogens in the paint.

e. In addition to the above, the tubes are required to be colour coded foridentification purposes, in compliance with the procedures given in BS 5383.

3.4 Packaging

a. After final inspection, the bores of the tubes are to be coated with waterrepellant oil to CS2060 and the tube ends protected by false flanges or plugs.The outside of the tubes are to be coated with CS1033 preservatives or otherapproved preparations.

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February 1999

4.1

4. DESIGN REQUIREMENTS/GUIDANCE(No relevant information included)

NES 864Issue 1February 1999

4.2

NES 864Issue 1

February 1999

5.1

5. CORPORATE EXPERIENCE AND KNOWLEDGE(No relevant information included)

NES 864Issue 1February 1999

5.2

NES 864Issue 1

February 1999

ANNEX AA.1

ANNEX A..

RELATED DOCUMENTS

A.1. The following documents and publications are referred to in this NES:

BS EN10002−1

Tensile testing of metallic materials. Methods of test at ambient tem-perature

BS EN10002−5

Tensile testing of metallic materials. Methods of test at elevated tem-peratures

BS 3600 Specification for dimensions and masses per unit length of welded andseamless steel pipes and tubes for pressure purposes.

BS 3602 Steel pipes and tubes for pressure purposes:Carbon and carbon−manganese steel with specified elevated tempera-ture properties.Part 1: Specification for seamless and electric resistance welded includ-ing induction welded tubes

BS 3604 Steel pipes and tubes for pressure purposes:Ferritic alloy steel with specified elevated temperature properties.Part 1: Specification for seamless and electric resistance welded tubes

BS 3920 Derivation and verification of elevated temperature properties for steelproducts for pressure purposes.Part 1: Method for deriving the minimum elevated temperature yield orproof stress properties when data on a minimum of 50 casts are avail-able.

BS 5383 Specification for material identification of steel, nickel alloy and tita-nium alloy tubes by continuous character marking and colour coding ofsteel tubes.

JSP 430 Vol 1: Policy and Guidance on MOD Ship and Equipment Safety Man-agement

SSP25 Quality Assurance for Safety in Submarines

NES 864Issue 1February 1999

ANNEX A A.2

NES 864Issue 1

April 1999

ANNEX BB.1

ANNEX B.

ABBREVIATIONS

B.1. For the purpose of this NES the following abbreviations an definitions apply:

Batch A batch is to consist only of tubes of the same diameter andwall thickness, from the same cast and subjected to the samefinal heat treatment in a continuous furnace or a batch typefurnace.

CFS Cold Finish Seamless − Terminology describing the condi-tion of the tube before final heat treatment is applied.

The Cold Finish Seamless condition requires the final pipeproduction stages to be carried out in the cold working tem-perature range.

Eccentricity(of tube bore)

The distribution of maximum and minimum wall thicknessesmeasured around the circumference of the tube.

First Level Quality Assur-ance

Where the consequences of failure of a hull area, system orequipment are such that they would lead to loss of the sub-marine, these areas, systems and equipments will be classi-fied as First Level and additional Quality Assurance mea-sures will be implemented. These requirements are definedin SSP25.

First Level System A submarine system subject to First Level Quality Assur-ance.

o.d. outside diameter of tube

Ovality The ratio of maximum external to minimum external diame-ter of the pipe.

Tubes The terminology ‘tubes’ is used throughout this NES but nodistinction is intended between ‘tubes’ and ‘pipes’.

Seamless Tube A tube manufactured by a procedure in which no longitudi-nal joint or seam is incorporated in the product.

SOQR Statement of Quality Requirements

NES 864Issue 1April 1999

ANNEX B B.2

NES 864Issue 1

April 1999

ANNEX CC.1

ANNEX C.

PROCUREMENT CHECK LIST

Notes:

1. This Check List is to ensure that certain aspects of this Naval Engineering Standardare consulted when preparing a Statement of Technical Requirements for a particularapplication.

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

3. Each item is to be marked either

" = included

NA = not applicable

Check No Check ClauseNo

"or NA

1. That the grade of steel required is specified 1.1.1

2. Whether there is a recommendation that a productanalysis is required

1.1.3

3. Whether dimensions and/or tolerances outside thosegiven in this NES are required

1.3.2

4. Whether lengths other than random lengths are re-quired

1.3.4

5. Whether verification procedure for Elevated Tempera-ture Properties by testing is required and the tempera-ture at which this is to be carried out

3.1.2.2

6 Whether the tubes are First Level items which mustsatisfy the requirements of SSP25

3.2.4

NES 864Issue 1April 1999

ANNEX C C.2

NES 864Issue 1

February 1999

ANNEX DD.1

ANNEX D.

PROCEDURE FOR VERIFICATION OF ELEVATED TEMPERATURE PROPERTIES

D1. Verification that any specific cast of steel from which the pipes have been manufactured,meets the elevated temperature strength requirements, is to be carried out by the proceduresspecified in BS 3920 Part 1.

D2. The basis of the procedure referred to in Clause D1 is that the manufacturer comparesappropriate data relating to his product, with the confidence lines that have been determinedfrom a large body of data and used to derive specification minimum values given in thisstandard.

D3. Information required for the construction of the lower confidence lines necessary for theapplication of the procedure are given in Tables D1 − D3 from BS 3602 Part 1 and BS 3604Part 1, respectively.

Temperature0.2% proof stress at two levels of room temperature tensile

strength300 N/mm2 500 N/mm2

°C N/mm2 N/mm2

100 147 262

150 140 245

200 127 221

250 108 199

300 90 183

350 79 169

400 72 161

450 70 153

TABLE D1: PARAMETERS FOR LOWER CONFIDENCE LINES −STEEL GRADE CFS 360 AND CFS 430

Temperature0.2% proof stress at two levels of room

temperature tensile strength480 N/mm2 610 N/mm2

°C N/mm2 N/mm2

100 289 351

150 270 325

200 249 297

250 225 275

300 201 255

350 182 238

400 166 224

450 154 213

TABLE D2: PARAMETERS FOR LOWER CONFIDENCE LINES −STEEL GRADE CFS 500 Nb

NES 864Issue 1February 1999

ANNEX D D.2

Temperature0.2% proof stress at two levels of room temperature tensile

strength300 N/mm2 500 N/mm2

°C N/mm2 N/mm2

100 256 336

150 245 330

200 236 326

250 227 319

300 183 274

350 173 262

400 166 252

450 160 243

500 158 236

550 156 227

TABLE D3: PARAMETERS FOR LOWER CONFIDENCE LINES −STEEL GRADE CFS 620

D4. An example of the confidence lines for the verification procedure referred to in Clause D1 isshown in Figure D1 for Grade CFS 430 steel. To achieve the appropriate degree of accuracy,however, it is necessary to construct the confidence lines on a larger scale. To facilitate this,the co−ordinates of two suitably spaced points on the lines, appropriate to the various gradesof steel at each temperature are given in Tables D1 and D3. Application of the verificationprocedure is to be in compliance with requirements of BS 3920 Part 1.

NES 864Issue 1

February 1999

ANNEX DD.3

100

150

200

250

300

350400450

300 400 500

Tensile Strength at Room Temperature

0.2%proof stressat to C

Rm N/mm 2

260

240

200

160

to C

Figure D1: Example of Lower Confidence Lines (for Grade CFS 430)

NES 864Issue 1February 1999

ANNEX D D.4

NES 864Issue 1

September 1999

ANNEX EE.1

ANNEX E.

INTERPRETATION OF SSP25 REQUIREMENTS APPLYING TO STEEL TUBESINTENDED FOR USE IN FIRST LEVEL SYSTEMS

E1. This Annex provides the guidance on the interpretation of SSP25 Quality Assurance require-ments as applied to steel tubes intended to ruse in first level systems. It isnot a comprehensivestatement of the requirements and should be read in conjunction with SSP25. Additional re-quirements may be included in the Contract or SOQR.

Property SSP25 Requirement

Chemical Analysis Certification giving the actual results of the chemicalanalysis, i.e. a statement that the result was withinspecification is not adequate.

Mechanical Properties Certification giving the actual results of the mechanicaltests required by the standard, i.e. a statement that theresults were within specification is not adequate.

Heat treatment SSP25 states that heat treatment records are generally onlyrequired where heat treatment is carried out aftermechanical testing. This would not apply to tubes coveredby this NES, so no heat treatment certification would berequired.

Non−destructive examination Ultrasonic inspection must be carried out on all First Leveltubes. Certification is to include the details of the procedure,equipment and operator used to carry out the examination,and the acceptance standard used to confirm thatsatisfactory results have been obtained.

Dimensional Certification that the dimensions are in accordance with thespecified requirements.

Pressure Test: Tubes less thanor equal to 180mm o.d.

Pressure test to be carried out in accordance with thespecification requirements. For tubes the “pressure test” isa hydraulic leak tightness test. The material specification,BS3602, permits eddy current testing in lieu of thehydraulicpressure test, at the discretion of the manufacturer unlessspecified by the purchaser. Where a pressure test is carriedout, certification must be provided to show that the testsrequired have been carried out with satisfactory results.Where eddy current testing is carried out, the resultspresented must be as stated against non−destructiveexamination above.

Pressure Test: Tubes greaterthan 180mm o.d.

Pressure test is carried out in accordance with thespecification requirements. For tubes the “pressure test” isa hydraulic leak tightness test; for tubes greater than180mm o.d. this test is mandatory. Certification must beprovided to show that the tests required have been carriedout with satisfactory results.

Unique Identity The tube must have a unique identity which can be relatedto the certificates described above.

NES 864Issue 1September 1999

ANNEX E E.2

NES 864Issue 1

April 1999

INDEX1

ALPHABETICAL INDEX

(Note: Page numbers are given)

BBatch type furnaces, 1.4

CChemical composition, 1.1

Colour coded, 3.4

Continuous furnaces, 1.4

DDestructive tests, 1.6, 3.2

Dimensions and tolerances, 1.4

FFirst level Quality Assurance, 3.3, E.1

HHeat treatment, 1.4, 1.6, 3.3, E.1

IInspection, visual, 1.5

Inspection, dimensional, 1.5

LLeaktightness, 1.6

MMechanical tests, 1.6, E.1

PPercentage elongation, 1.7

Permissible deviation, 1.2, 1.4

Preservatives, 3.4

Pressure test, 1.6, 3.2

RResidual elements, 1.1

SStatement of Quality Requirements, 3.4, E1

Steel manufacture, 1.3

Surface imperfections, 1.5, 3.1

TTest certificate, 3.3

NES 864Issue 1April 1999

INDEX2

Inside Rear Cover

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