En 764-4-2002 [PDF]

Zitiervorschau

EUROPEAN STANDARD

EN 764-4

NORME EUROPÉENNE EUROPÄISCHE NORM

October 2002

ICS 23.020.30

English version

Pressure equipment - Part 4: Establishment of technical delivery conditions for metallic materials Equipements sous pression - Partie 4: Etablissement des conditions techniques de livraison des matériaux métalliques

Druckgeräte - Teil 4: Erstellung von technischen Lieferbedingungen für metallische Werkstoffe

This European Standard was approved by CEN on 19 August 2002. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: rue de Stassart, 36

© 2002 CEN

All rights of exploitation in any form and by any means reserved worldwide for CEN national Members.

B-1050 Brussels

Ref. No. EN 764-4:2002 E

EN 764-4:2002 (E)

Contents page Foreword......................................................................................................................................................................3 1

Scope ..............................................................................................................................................................4

2

Normative references ....................................................................................................................................4

3 3.1 3.2

Terms and definitions, symbols and abbreviations ...................................................................................5 Terms and Definitions ...................................................................................................................................5 Symbols and abbreviations ..........................................................................................................................5

4 4.1 4.2 4.3

Types of technical delivery conditions........................................................................................................7 European Standards for material for pressure equipment........................................................................7 European approvals for materials for pressure equipment ......................................................................7 Particular material appraisals for pressure equipment .............................................................................7

5 5.1 5.2 5.3 5.4

Content of technical delivery conditions for materials for pressure equipment ....................................8 General............................................................................................................................................................8 Requirements .................................................................................................................................................8 Testing and inspection................................................................................................................................10 Marking .........................................................................................................................................................11

Annex A (normative) Procedures for the establishment of European Approvals for pressure equipment materials (EAM).........................................................................................................................12 A.1 European Approvals of established materials..........................................................................................12 A.2 European Approvals for new materials .....................................................................................................12 A.3 Procedure for the transformation of existing national material specifications into European Material Data Sheets....................................................................................................................................12 A.4 First testing of the production of established materials .........................................................................15 A.5 First testing of the production of new materials ......................................................................................16 A.6 Title scheme and structure of a European Material Data Sheet (EMDS) for materials for Pressure Equipment ....................................................................................................................................17 Annex B (normative) Appraisal schedule for ferritic and martensitic steels ......................................................20 B.1 General..........................................................................................................................................................20 B.2 Test procedures ...........................................................................................................................................20 B.3 Basic testing.................................................................................................................................................21 B.4 Subsequent testing......................................................................................................................................24 B.5 Collective tests.............................................................................................................................................25 Annex C (normative) Appraisal schedule for austenitic and austenitic-ferritic steels ......................................27 C.1 General..........................................................................................................................................................27 C.2 Test procedures ...........................................................................................................................................27 C.3 Basic testing.................................................................................................................................................28 C.4 Sampling .......................................................................................................................................................30 C.5 Extent of testing ...........................................................................................................................................35 Annex D (normative) Appraisal schedule for cast steels......................................................................................36 D.1 General..........................................................................................................................................................36 D.2 Test procedures ...........................................................................................................................................36 D.3 Basic testing.................................................................................................................................................37 D.4 Sampling .......................................................................................................................................................39 D.5 Extent of testing ...........................................................................................................................................39 Annex E (normative) Welding and heat treatment conditions for verification of the weldability of finegrain steels ...................................................................................................................................................40 E.1 General..........................................................................................................................................................40 E.2 Determination of the cooling time..............................................................................................................40 E.3 Heat treatment conditions...........................................................................................................................41 Annex F (normative) Metallographic investigation of the sensitivity to stress relief cracking ........................42 Bibliography ..............................................................................................................................................................43 2

EN 764-4:2002 (E)

Foreword This document EN 764-4:2002 has been prepared by Technical Committee CEN/TC 54 "Unfired pressure Vessels", the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by April 2003, and conflicting national standards shall be withdrawn at the latest by April 2003. This European Standard “Pressure equipment” consists of seven Parts which are: 

Part 1: Pressure, temperature, volume, nominal size.



Part 2: Quantities, symbols and units.



Part 3: Definition of parties involved.



Part 4: Establishment of technical delivery conditions for materials.



Part 5: Compliance and Inspection Documentation of Materials.



Part 6: Operating instructions.



Part 7: Safety systems and unfired pressure equipment.

Annexes A to F are normative. The terminology for safety systems is dealt with in prEN 13340 Pressure equipment — Safety devices for the prevention of excessive pressure — Terminology. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.

3

EN 764-4:2002 (E)

1

Scope

This Part of the European Standard specifies the requirements for the establishment of the technical delivery conditions in form of: 

harmonized European Standard for material;



European approval for material (EAM);



particular material appraisal

for metallic materials for pressure equipment in all product forms, and is restricted to steel at present. Welding consumables are not covered by this standard.

2

Normative references

This European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). prEN 764-1:2001, Pressure equipment — Terminology -Part 1: Pressure, temperature, volume, nominal size. EN 764-2:2002, Pressure equipment — Terminology - Part 2: Quantities, symbols and units. EN 895, Destructive tests on welds in metallic materials — Transverse tensile test. EN 1011-2, Welding — Recommendations for welding of metallic materials — Part 2: Arc welding of ferritic steels. EN 10002-1, Metallic materials — Tensile testing — Part 1: Method of test at ambient temperature. EN 10002-5, Metallic materials — Tensile testing — Part 5: Method of testing at elevated temperature. EN 10045-1, Metallic materials —Charpy impact test — Part 1: Test method. EN 10045-2, Metallic materials —Charpy impact test — Part 2: Verification of the testing machine (pendulum impact). EN 10204:1991, Metallic products — Types of inspection documents. EN 10213-1, Technical delivery conditions for steel castings for pressure purposes — Part 1: General. EN 10291, Metallic materials — Uniaxial creep testing in tension — Method of test. EN 13445-2:2002, Unfired pressure vessels — Part 2: Materials. prEN ISO 17642-1, Destructive tests on welds in metallic materials — Cold cracking tests for weldments — Part 1: General. prEN ISO 17642-2, Destructive tests on welds in metallic materials — Cold cracking tests for weldments — Part 2: Self-restraint tests. prEN ISO 17642-3, Destructive tests on welds in metallic materials — Cold cracking tests for weldments — Part 3: Externally loaded tests. EURONORM 103-71, Microscopic determination of the ferrite or austenitic grain size of steels. 4

EN 764-4:2002 (E)

CR ISO 15608:2000, Welding — Guidelines for a metallic material grouping system (ISO/TR 15608:2000). EURONORM 114-72, Determination of the resistance of stainless austenitic steels to intergranular corrosion; corrosion test in sulfuric acid copper sulfate solution (Monypenny-Strauss test).

3

Terms and definitions, symbols and abbreviations

For the purposes of this European Standard the following terms and definitions apply.

3.1

Terms and definitions

3.1.1 European Approval for materials (EAM) technical approval for materials for pressure equipment with no harmonized standard, see also [1], Article 11 3.1.2 European Material Data Sheet (EMDS) document defining the requirements for a material approved for use in the manufacture of pressure equipment by a European approval for materials according to the provisions of annex A 3.1.3 established material metallic materials specified in a product standard for pressure equipment; or in an EAM 3.1.4 new material metallic material not included in a product standard or in an EAM

3.2

Symbols and abbreviations

For the purposes of this standard the symbols and abbreviations of prEN 764-1:2001, EN 764-2:2002 and the following in Table 1 and Table 2 will apply.

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EN 764-4:2002 (E)

Table 1 — Symbols and units Symbols

a

6

Characteristic

Units

b

width

mm

e

thickness

mm

h

max. permissible reinforcement of weld

mm

T

temperature

°C

TD

design temperature

°C

A

elongation after fracture

%

C

constant

D

diameter

mm

E

modulus of elasticity

N/mm

2 a

G

shear modulus

N/mm

2 a

HB

Brinell hardness

—

HV

Vickers hardness

—

KV

Charpy V-notch impact energy

J

Lo

length (gauge length)

mm

P

pressure

bar

PLM

parameter according to Larson-Miller

Re

yield strength

N/mm

2 a

ReH

upper yield strength

N/mm

2 a

ReL

lower yield strength

N/mm

2 a

Rm

tensile strength

N/mm

2 a

Rm/t/T

creep rupture strength for t hours at T °C

N/mm

2 a

Rm/T

tensile strength at temperature T

N/mm

2 a

Rp0,2/T

0,2 % proof strength at temperature T

N/mm

2 a

Rp0,2

0,2 % proof strength

N/mm

2 a

Rp1,0

1,0 % proof strength

N/mm

2 a

Rp1,0/T

1,0 % proof strength at temperature T

N/mm

2 a

S0

original cross section area

mm

t

time

h

α

linear expansion coefficient

K−

ε

strain

%

v

Poisson's ratio 2

1 N/mm = 1 MPa

—

—

2

1

—

EN 764-4:2002 (E)

Table 2 — Abbreviations Abbreviation

Description

EAM

European approval of material

EC

European Commission

EMDS

European material data sheet

NDE

non destructive examination

PED

Pressure equipment directive

OJEC

Official Journal of European Communities

RA

Responsible authority

4 4.1

Types of technical delivery conditions European Standards for material for pressure equipment

European material Standards define the technical requirements for materials frequently used in pressure equipment in Europe. It is within the remit of the responsible technical committee for materials to check at each occasion of the revision work whether related materials covered by a European Material Data Sheet (EMDS) are used to an extent that justifies the incorporation of the material in the European material Standard.

4.2

European approvals for materials for pressure equipment

European approvals for materials are intended for repeated use. They are established on the basis of Article 11 of the PED and apply to materials or treatment conditions and product forms or dimensions not covered in a harmonized European material Standard for pressure equipment. The European approval for materials for pressure equipment result in European Material Data Sheets. NOTE Reference of available European Material Data Sheets is published in the Official Journal of the European Community (OJEC).

4.3

Particular material appraisals for pressure equipment

Particular material appraisals apply for individual cases as for example: a) a material or a product form or a thickness not covered by a harmonized European material Standard or EMDS intended for use in a particular pressure equipment; b) a product specified in a European material Standard or EMDS for materials for pressure equipment is intended in an exceptional case for service conditions outside its specified range of application. NOTE Under the scope of the PED for pressure equipment in category III and IV the particular material appraisal shall be performed by the Notified Body in charge of the conformity assessment for the pressure equipment.

Where relevant to the pressure equipment under consideration the requirements given in annexes B to F may be used as guidance.

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EN 764-4:2002 (E)

5

Content of technical delivery conditions for materials for pressure equipment

5.1

General

Technical delivery conditions for materials for pressure equipment shall describe the material with its specific properties and shall at least contain clauses for scope, normative references, requirements, testing and inspection and marking and restriction on application where necessary. EMDS and particular material appraisals shall take account of material processing. If appropriate, information on the allocation of the material to the relevant material group in CR ISO 15608 shall be provided with the technical material specification. Particular material appraisals shall always specify in detail the range of application. For EMDS a list of material manufacturers shall be provided where appropriate.

5.2

Requirements

5.2.1

Manufacture

The method of manufacture of the material shall be specified. Details need only be specified to an extent as is necessary to ensure the specified quality. 5.2.2

Treatment condition

The following conditions shall be specified: 

type of heat treatment condition;



surface condition of the material at the time of delivery, where necessary.

5.2.3

Chemical composition

The chemical composition limits shall be specified. Where the composition of the product may be different from the composition of the cast, limit deviations from the cast analysis shall be specified. The specification of the chemical composition shall include the following: "Elements, which can influence the essential material characteristics, not specified for the specific material shall not intentionally be added. All reasonable precautions shall be taken to prevent the addition of elements from scrap or other materials used in the manufacture, but residual elements may be present, provided the specified mechanical properties are met and the applicability is not impaired."

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EN 764-4:2002 (E)

5.2.4

Mechanical and technological properties

The following properties shall be specified for the individual steel grades. a)

Tensile properties at room temperature The technical material specification shall specify the tensile properties in the direction and location of test pieces which shall be representative of the material characteristics. Where the form and thickness of the products permit the verification testing of transverse test pieces, the property characteristics shall be given for the transverse direction. In those cases, where the properties in the longitudinal direction are lower, this shall be taken into account; 1)

Yield or proof strength For austenitic steels minimum proof strength values for 1 % non proportional extension (Rp1,0/min and, where appropriate, Rp0,2/min values additionally) shall be specified. For all other materials the minimum value for the upper yield strength or, for cases where no yield phenomenon occurs, the minimum proof strength for 0,2 % non proportional extension shall be specified;

2)

Tensile strength For the tensile strength a minimum value shall be specified. A maximum value shall be specified additionally where no maximum yield or proof strength value is specified;

3)

Elongation after fracture The minimum percentage elongation after fracture for the gauge length specified in accordance with EN 10002-1 shall be specified;

b) Impact properties The impact requirements of the material (temperature, energy) shall be specified with regard to the pressure equipment requirements to avoid brittle fracture; c) Elevated temperature tensile properties 1)

The following tensile properties shall be specified for temperatures in accordance with Table 3:



for austenitic steels intended for an application at a temperature ≥ 50 °C and in accordance with Table 3 the minimum 1,0 % proof strength at elevated temperatures. It is also proposed to specify the minimum elevated temperature tensile strength;



for all other steels intended for an application at a temperature in accordance with Table 3, but not higher than the maximum design temperature rounded up to 50 K, the minimum 0,2 % proof strength at elevated temperatures.

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EN 764-4:2002 (E)

Table 3 — Elevated temperatures for steels Steel group from

to a maximum of

preferably in steps of

°C

°C

K

2, 7.1, 7.2, 3 1.1 to 1.3

100

400

50

1.4, 4, 5.1, 5.2

100

500

50

5.3, 5.4, 6

100

600

50

8

50

600

50

10

50

250 a

50

in accordance with CR ISO 15608:2000

a

2)

Temperature

250 °C if welded, 280 °C unwelded

The specified minimum proof strength values at elevated temperatures should be derived in accordance with prEN 10134 on the basis of data determined in accordance with EN 10002-1 and EN 10002-5;

d) Technological properties Where necessary, requirements for formability e.g. specified on the basis of flattening or ring expanding tests or on the basis of tests for the deformation properties perpendicular to the surface of the product (see EN 10164) or requirements for other technological properties, important for the processing or use of the material, shall be specified. 5.2.5

Other material properties

Where necessary, the requirements for properties other than those covered under 5.2.2 to 5.2.4, as for example requirements referring to the corrosion resistance of the material shall also be specified together with their methods of verification. 5.2.6

Freedom of surface and internal defects

The requirements for non destructive testing and visual inspection shall be specified where necessary to meet the relevant requirements in EN 13445-2:2002, 4.1.3. 5.2.7

Dimensions, shape, mass and related tolerances

Dimensions, shape and mass and related tolerances shall be specified where necessary, preferably by reference to an appropriate dimensional standard.

5.3

Testing and inspection

The following requirements on inspection and testing shall be specified: a)

the types of applicable inspection documents (see EN 10204);

b)

the requirements to be verified (e.g. chemical composition, tensile properties);

c)

the conditions applicable for specific inspection and testing namely: 

10

the composition and maximum size of the test unit (e.g. the maximum weight or number of products of the same cast, heat treatment batch); and

EN 764-4:2002 (E)

d)

5.4



the number of sample products per test unit;



the number of samples per sample product; and



the number of test pieces per sample to be taken and tested;



the location and direction of the test pieces in the product;



where necessary, additional conditions for sampling and conditions for the preparation of the samples and test pieces;



the European Standards in which the test methods are described;



the provisions for retesting;

any other necessary specification for testing and inspection.

Marking

The marking of the delivery units or products shall ensure traceability between these and the inspection documents. For European standardized materials the marking shall fulfil the requirements of the relevant product standard. For other materials the marking shall at least contain: a)

the material specification (reference, material designation);

b)

the material manufacturers name or mark;

c)

the stamp of the inspection representative, if applicable;

d)

an identification which permits the correlation between the product or delivery unit and the relevant inspection document.

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EN 764-4:2002 (E)

Annex A (normative) Procedures for the establishment of European Approvals for pressure equipment materials (EAM) A.1 European Approvals of established materials The following requirements shall apply for EAMs established by transformation of material specifications originally covered in national standards for material for pressure equipment or in national technical material data sheets approved by the body competent for such approvals. The following requirements shall apply: a)

the national material specification exists and is in force before the transformation commences;

b)

the sampling and testing conditions of the EAM are equivalent to a European Material Standard;

c)

the EAM shall be based on the requirements of the national specification;

d)

the requirements specified in the national specification should be backed by statistical data;

NOTE

For previous national specifications the original assessment reports may not be available.

e)

the compliance with these requirements shall be checked in accordance with the procedure indicated in A.4;

f)

the requirements of the appropriate product standard shall be met.

A.2 European Approvals for new materials European Approvals for new materials are established in accordance with A.5. They might be limited to a number of material manufacturers. A list of material manufacturer(s) shall be provided where appropriate.

A.3 Procedure for the transformation of existing national material specifications into European Material Data Sheets A.3.1 At request EAMs shall be issued by a Notified Body specifically designated for that task. An example of a form for request is given in Table A.1.

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EN 764-4:2002 (E)

Table A.1 — Necessary information for preparation of a European Material Data Sheet transposed from an existing standard or national material specification No

Data required

1

Name and address of the applicant

2

Denomination/No of nationally approved material specification

3

Date of first edition

4

Date of last edition

5

Material group

6

Material designation

7

Product form

8

Approved dimensions

9

Material manufacturing process

10

Comparable material specifications

11

Basis of the approval

12



Appraisal no (test report no) and date of issue, if applicable



experience (production, manufacture, application)



other

Actual data

Notified Body

A.3.2 The Notified Body shall verify the requirements of A.1. Where appropriate the detailed technical information summarised in Table A.2 shall be considered. After consideration the Notified Body shall prepare a draft EMDS in accordance with A.6. In order to ensure compliance of the specified material with the requirements of the applicable product standard, draft EMDS may contain additional conditions to the original standard/specification. Table A.2 — Detailed technical information for verifying the compliance of the nationally approved material specification with requirements for a European material data sheet No

Type of data or indications required

00

Reference data for the national material specification

02

Designation of nationally approved material specification

03

Date of first edition

04

Date of last edition

05

Material Group

06

Material designation

07

Product form

08

Approved dimensions

09

Type of manufacture

10

Deoxidisation

11

Delivery conditions of the material

Data or indications

13

EN 764-4:2002 (E)

No 12

Type of data or indications required

Data or indications

Range of application

13 14 15 20

Comparable material specifications

21 22 23

40

Verify the compliance with the pre-conditions

42

material specification existed prior to initiating work on the relevant European material standard

43

the requirements are backed by statistical data

44 45 50

Verify the compliance with the minimum requirements of clause 5. Explain the reasons for non compliance and the modification to be considered to achieve compliance

51

chemical composition

52

Tensile properties at room temperature 

Yield or proof strength;



Tensile strength;



Elongation after fracture;



Reduction of area after rupture.

53

Tensile properties at elevated temperatures

54

Impact properties

55 56

Technological properties

57

Other properties

58 59

14

60

Comparison of the sampling and testing conditions between the national approved material specification and the relevant European material standard

61

Type of applicable inspection documents

62

Chemical composition (test unit)

63

tensile test 

location and direction of test piece,



form of test specimens;



number of test specimens.

EN 764-4:2002 (E)

No 64

Type of data or indications required

Data or indications

impact test 

location and direction of test piece;



form of test specimens;



number of test specimens.

65

technological tests

66

other tests

70

Reduced additional tests and investigation

80

References to earlier assessment reports or expert opinions and other sources

81 82 83 90

Other data or notes

91 92 93

Date: .................................................

Name and address of Notified Body:.......................................................................................................................

Signature: ..........................................

A.3.3 The Notified Body shall issue the final European Material Data Sheet following the procedure described in Article 11 of the PED.

A.4 First testing of the production of established materials A.4.1 General The first production of an established material not previously produced by a material manufacturer shall be subject to first testing as defined in A.4.3. Where a material manufacturer has already produced very similar materials and can put forward data regarding chemical composition, material characteristics, manufacturing process and product forms, the data of this material shall be used in fulfilling the requirements of A.4.3. Where a material manufacturer applies only for an extension of the scope of an existing EAM and has experience with that material the amount of testing as defined shall be reduced and justification given in the assessment report.

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EN 764-4:2002 (E)

Where a material manufacturer has already produced and delivered the established material previously, and can provide satisfactory information on this material no testing as required in A.4.3 is requested.

A.4.2 Responsibilities The responsibility for the first testing and, unless otherwise agreed, for the assessment of the results of the relevant tests is: a)

in the case of materials of the steel groups 1.1, 1.2 and 8.1 in accordance with CR ISO 15608:2000 with the department of the material manufacturer competent for issuing certificates in accordance with EN 10204:1991, type 3.1.B certificate;

b)

in all other cases with the Notified Body.

A.4.3 Procedure for the first testing of established materials not previously produced The first three to five casts shall be melted to represent the specified range of material composition A.4.3.1 specified by the material manufacturer. The number of samples required by the technical delivery conditions shall be doubled for the first three A.4.3.2 to five casts, but not be greater than two samples per plate as rolled, coil, tube in manufactured length, forging or casting. Where two samples per sample product are taken they shall be from opposite ends of the product. In A.4.3.3 all other respects the sampling conditions shall be the same as specified in the technical delivery condition. For each sample a tensile test at room temperature and, where Charpy V-notch impact energy is A.4.3.4 specified in the technical delivery condition, three Charpy V-notch impact tests shall be carried out. Where the impact energy is specified for more than one temperature the test shall be carried out at the temperature for which the value of 27 J for ferritic and 1,5 % to 5 % Ni-alloyed steel and 40 J for austenitic material is specified or at the test temperature nearest to this energy level. For materials with specified tensile properties at elevated temperatures these properties shall be A.4.3.5 determined with reference to 5.2.4 c) for each cast melted in accordance with A.4.3.1 up to the defined maximum test temperature.

A.4.4 Statistical methods Where appropriate, the relevant data or test results shall be evaluated by the manufacturer according to common statistical procedures.

A.5 First testing of the production of new materials A.5.1 Requirements for the establishment of EAM for a new material A.5.1.1

When a new material is applied for an EAM the Notified Body shall establish, that

a)

the material is not covered in any other existing EAM;

b)

the proposal fulfils the requirements in clause 5;

c)

the material characteristics which are of importance for the intended processing and application of the material are available and whether these are at a level which does necessitate special precautions during processing and application, e.g.: 

16

cold and hot formability;

EN 764-4:2002 (E)

d)



weldability;



hardening and tempering behaviour;



ageing behaviour;



fatigue strength;



corrosion resistance;

the material characteristics necessary for the proposed EAM can be consistently fulfilled.

For the establishment of the EAM a test program shall be developed in co-operation between the A.5.1.2 material manufacturer and the Notified Body to fulfil the requirements in A.5.1.1 c) and d). The type and extent of testing shall consider the processing and use of the product forms as well as the expected minimum properties. Annexes B to F may be used as guidelines to select the relevant tests to be included in the test program. The test program shall involve 5 casts. The test program shall specify which tests shall be confirmed by the Notified Body.

A.5.2 Requirements for inclusion of additional material manufacturers in an EAM that is limited to certain manufacturers If a material manufacturer applies to be approved for the manufacture of a material specified in an EAM the requirements of A.5.1 shall be followed with the following exceptions: 

the test program shall be the one applied for the establishment of the original EAM. This program may be reduced or modified if justified by experience with this material;



unless considerable changes in the test program are intended A.5.1.2 does not apply.

NOTE

A.5.2 to be reconsidered with respect to PED guidelines on pressure equipment materials, as soon as available.

A.6 Title scheme and structure of a European Material Data Sheet (EMDS) for materials for Pressure Equipment A European Material Data Sheet (EMDS) for materials for Pressure Equipment shall contain the applicable elements given in the Table A.3 and the title scheme of that table.

17

EN 764-4:2002 (E)

Table A.3 — Title scheme and structure of a European Material Data Sheet (EMDS) for materials for Pressure Equipment European Material Data Sheet (EMDS) Logo

Title

1

Material designation

2

Product form

3

Dimensions

4

Scope (Range of application)

5

References

6

Requirements

6.1

Delivery conditions (heat treatment)

6.2

Type of manufacture (steelmaking process)a

6.3

Deoxidisationa

6.4

Chemical composition

EMDS No. .................... Date of issue: ......................................

Cast analysis Product analysis a European Material Data Sheet (EMDS) Logo

6.5

Title Mechanical and technological properties Tensile properties (e.g. ReH, ReL, Rp0,2, Rp1,0, Rm) and bend test at room temperature Tensile properties at elevated temperatures Impact properties Other tests e.g. hardness tests, ring tests

6.6

Surface treatment condition

6.7

Internal soundness

6.8

Other properties, if applicable (e.g. corrosion)

7

Testing and inspection

7.1

Types and content of inspection documents

7.2

Frequency of tests

7.3

Sampling and test piece preparation

7.4

Test procedures Chemical composition Tensile test at room temperature Tensile test at elevated temperatures Impact test Visual and dimensional examination Leak tightness test a

18

EMDS No. .................... Date of issue: ......................................

EN 764-4:2002 (E)

Intercristalline corrosion resistance Identification test Non destructive testing Other tests 7.5

Re-tests

8

Marking

9

Guidelines for processing

9.1

Cold and hot forming

9.2

Welding, thermal cutting

9.3

Post weld heat treatment

10

Design data a

11

Other data a

12

List of material manufacturers .............................................................................................................. ..............................................................................................................

13 a

EMDS prepared by where applicable

19

EN 764-4:2002 (E)

Annex B (normative) Appraisal schedule for ferritic and martensitic steels B.1 General The purpose of this annex is to provide a list of properties and test procedures which may be relevant in the characterisation of new ferritic and martensitic steels and the determination of material property requirements. When assessing the material property requirements, for each specific material, the material properties to be assessed for which parameters have to be specified shall be selected in accordance with A.5.1.1. The following requirements are valid for rolled or forged ferritic-perlitic steels, including normalised fine-grain steels1), and martensitic or bainitic air or liquid quenched and tempered steels and copper bearing age hardened steels.

B.2 Test procedures B.2.1 The type of the testing depends on the processing and use of the product forms in question. Tests shall be carried out in the normal delivery conditions unless otherwise specified. The applicable test standards shall be indicated. B.2.2 In the case of a simultaneous appraisal of a number of product forms or thicknesses, the samples to be tested shall be selected, that they cover the scope proposed for appraisal and the required manufacturing procedures. Endeavours shall be made to select as low a number of test samples as possible, covering the whole size range, see Table B.1. B.2.3 The appraisal of the product forms shall be performed with respect to the thickness for each product form as given in Table B.1. Table B.1 — Wall thickness for product forms Dimensions in millimetres

thickness

Product form

I

II

III

Strip


70

Tube

< 30

30

to 70

> 70

Forging/rolled bar

< 150

150

to 300

> 300

4,5

4,5 to 12

> 12

B.2.4 The products to be tested should be at the upper limit of the requested thickness range, i.e. not less than 80 % of the proposed maximum thickness. B.2.5 The tests may be divided into those, which shall be conducted before the first delivery (basic testing) and those, which shall be carried out during initial deliveries (subsequent testing).

1)

20

Fine-grain steels are those unalloyed or low-alloyed steels with a grain size of 6 or finer in accordance with EUR 103-71

EN 764-4:2002 (E)

B.2.6

Testing shall generally be performed as follows:

Normally the tensile testing is performed over the full thickness for a product thickness e ≤ 30 mm. For a product thickness e > 30 mm the thickness may be reduced to ≥ 30 mm retaining one rolled surface on the rectangular test piece. Circular test pieces are permissible but shall only be provided for a product thickness e > 30 mm. The specimen diameter shall be at least 10 mm. For a product thickness e > 70 mm a circular test specimen taken from mid thickness of the product shall be tested additionally. For the impact tests the test specimens shall be taken near the surface for a product thickness e ≤ 40 mm. For a product thickness e > 40 mm the location for the specimen shall be in e/4, for e > 70 mm additionally in e/2.

B.3 Basic testing B.3.1 General Basic testing shall be conducted by each material manufacturer on at least two casts, which should cover the specified range of analysis and of the heat treatment.

B.3.2 Determination of the chemical composition The cast analysis shall be given by the material manufacturer. The product analysis shall be carried out on samples to determine all elements given by the material data sheet.

B.3.3 Tensile tests Tensile tests at room temperature shall be carried out in accordance with EN 10002-1 to determine the B.3.3.1 upper and lower yield strength (or should not yield strength be indicated, the 0,2 % proof strength) tensile strength, elongation after fracture (A) and reduction of area. Samples shall be tested in the longitudinal and transverse/tangential directions. The test results will indicate the degree of directionality occurring in the properties of a product and the direction with inferior mechanical properties. Trend curves up to 50 K above the maximum operating temperature in accordance with prEN 10134 B.3.3.2 shall be determined for steels for which the minimum values of elevated temperature proof strength are intended to be specified.

B.3.4 Notched bar impact tests Notched bar impact tests shall be carried out to determine the upper and lower shelf by a complete transition curve. Impact energy temperature curves are required for both longitudinal and transverse/tangential direction (with determination of the shear fracture percentage and the lateral expansion). For each curve tests shall be carried out for six temperatures in accordance with EN 10045.

B.3.5 Technological tests As far as for the new product specific technological properties need to be characterised, bend tests, flaring tests, flanging tests, ring tensile tests, ring flattening tests, ring expansion tests or other tests appropriate to the material shall be carried out.

B.3.6 Metallographic investigation Metallographic examination shall be carried out to assess microstructure, grain size and impurities. 21

EN 764-4:2002 (E)

B.3.7 Hardness testing In the case of quenched and tempered and thermomechanically rolled materials, a hardness survey over the product thickness shall be carried out to determine homogeneity.

B.3.8 Production of a tempering chart for quenched and tempered and age-hardened steels The tempering characteristic shall be determined for yield strength, tensile strength, yield strength to tensile strength ratio, elongation at fracture, reduction of area and impact energy at a minimum of three different of tempering temperatures between 550 °C and 700 °C and for two tempering times. Tempering temperatures and holding times shall be transformed in Larson-Miller parameters and the change of the mechanical properties shall be plotted over the Larson-Miller parameter2). Temperatures and times should be fixed as to reveal any tendency towards tempering embrittlement. Tensile tests shall be conducted and impact tests with Charpy V-notch transverse specimen at three typical temperatures in the transition range including the lowest specified temperature.

B.3.9 Determination of the transformation behaviour In order to estimate the transformation behaviour of transformable steels the transition points shall be determined by tests. A continuous cooling-transformation diagram shall be produced for quenched and tempered or agehardened steels (see EN 10052).

B.3.10

Investigation of the effect of stress relief

Tensile tests at room temperature and higher temperature, as well as impact tests with Charpy V-notch transverse specimens at three typical temperatures in the transition range including the lowest specified temperature, shall be carried out on stress relieved test pieces, for a representative range of product thickness. In case of plate materials the specimen should be from material between 30 mm and 40 mm. NOTE The change of the strength and notch ductility values at three stress relief conditions (e.g. with 1 temperature at the lowest specified temperature for stress relief with 1 h holding time. 1 at the highest specified temperature for stress relief with 15 h holding time and 1 between these extreme conditions) can be demonstrated by expressing the stress relief conditions by Larson-Miller-Parameter and plotting the results of the mechanical testing over the Larson-Miller-Parameter.

The specimens shall be tested in the directions with the lowest results of testing in accordance with B.3.2.1 and B.3.3.

B.3.11

Investigation of the effect of cold forming

B.3.11.1 Determination of the cold formability Cold forming shall be carried out by straining with two levels of deformation, preferably 2 % and 5 %. If a higher level than 5 % deformation is required this shall be carried out in place of the 5 % deformation. Notched bar impact tests on Charpy V-notch transverse specimen shall be carried out to determine impact energy-temperature curves in the cold formed condition. If the level of deformation is greater than 5 % similar tests shall also be carried out after stress relief heat treatment (in a typical stress relief condition). Where the level of deformation is 5 % or greater tensile tests shall be carried out additionally in both cold formed conditions and after stress relief heat treatment.

2)

22

Larson-Miller Parameter or Hollomon Parameter 3 HP = t (20 × Ig T) × 10− T = temperature in °K t = holding time in min

EN 764-4:2002 (E)

B.3.11.2 Determination of the susceptibility to strain age embrittlement Susceptibility to strain age embrittlement is tested by subjecting the material to 5 % or to the highest permissible degree of cold forming followed by tempering at 250 °C/30 min. Charpy V-notch impact tests shall then be carried out at three characteristic temperatures on transverse Charpy V-notch specimens including the lowest specified temperature.

B.3.12

Investigation of the behaviour of the base material after welding

B.3.12.1 General The requirements apply primarily to fine-grain steels. They may require modifications for applications to other steels. The welding consumables shall, taking into consideration the welding conditions, be chosen in such a way that the weld metal complies with the minimum requirements for the properties of the base metal but that its strength is not much higher than the minimum values specified for the base metal. B.3.12.2 Welded joints Tests on butt welds with varying heat inputs respectively varying cooling times t 8/5 shall be carried out. The weld seam shall be parallel to the direction of rolling. The joint should have a steep level with a maximum angle of 5 degrees. The welding conditions and heat treatment are summarised in annex E. The welded joints shall be tested in the as-welded condition. The following tests shall be performed: 

one tensile test across the weld in accordance with EN 895;



an impact energy transition curve from the heat affected zone on Charpy V-notched specimens with the notch at right angles to the surface and in the coarse grain zone at a distance of 0,5 mm ± 0,3 mm besides the fusion line to determine the toughness in the heat affected zone. The notched bar impact energy and crystalline percentage shall be determined;



root and face bend tests;



side bend test specimen;



macrosection;



grain structure assessment of the microsection;



hardness measurement (HV 10 series with determination of the maximum hardness in the centre and 2 mm below the surface).

B.3.12.3 Weld surfacing For steels with a specified minimum yield strength > 355 N/mm , stringer beads should be applied to a test piece with a thickness ≥ 30 mm, one without preheat, one at 120 °C and one at 200 °C, with 3,25 mm diameter rod electrodes using the complete length of the electrode minus the stub. 2

A series of hardness tests shall be carried out parallel to the surface and tangential to the root of the fusion line through the heat affected zone both in the as-welded and heat treated condition, b and d as per E.3. B.3.12.4 Susceptibility to cold cracking Susceptibility of the material to hydrogen-induced cracking shall be investigated in fine-grain steels and quenched 2 and tempered steels and thermomechanical steels with a specified minimum yield strength > 335 N/mm and a product thickness ≥ 20 mm. 23

EN 764-4:2002 (E)

One of the following methods should be applied which are specified in prEN ISO 17642-1, prEN ISO 17642-2 or prEN ISO 17642-3 

Implant test;



Tekken test;



CTS test.

B.3.12.5 Influence on mechanical properties of a stress-relief treatment on welded joints B.3.12.5.1 Influence of a stress-relief treatment on mechanical values In steels with minimum yield strength > 335 N/mm the influence of different stress-relief treatments on the tensile values and especially on the impact values in the HAZ shall be determined. 2

The following testing shall be conducted on test specimens as far as possible from the casts in accordance with B.3.11.2 in the stress relieved conditions b and d (see E.3): 

one tensile test across the weld;



impact test on Charpy V-notch specimen with the notch at right angles to the surface and (0,5 ± 0,3) mm from the fusion line in the heat affected zone, at minimum 3 temperatures to characterise the impact behaviour of the HAZ in the stress relief condition compared to the as welded condition;



hardness measurement (HV 10) perpendicular to the welding direction across the heat affected zone.

B.3.12.5.2 Sensitivity to stress relief cracking In the case of materials for which crack development during stress relief heat treatment may be anticipated (e.g. Cr, Mo, V, Nb, B steels), this shall be checked on at least one cast. In the case of doubt a metallographic investigation should be carried out, e.g. in accordance with annex F.

B.3.13

Thermal cutting

Investigation of the influence of thermal cutting is required. The material manufacturer shall verify by appropriate thermal cutting tests with and without preheating which conditions allow for thermal cutting without crack formation. Additionally it shall also be indicated which precautions shall be taken for cold bending of thermally cut parts.

B.4 Subsequent testing Subsequent tests shall be carried out to "round off" the still necessary investigations of each material manufacturer. They should be carried out without delay not later than with the first deliveries and should be completed in a reasonable time.

B.4.1 Long term tests B.4.1.1

Ageing tests

In the case of quenched and tempered and age-hardened steels, for elevated temperature applications, ageing tests shall be carried out.

24

EN 764-4:2002 (E)

B.4.1.2 NOTE

Creep rupture tests Not considered at present.

B.4.2 Further brittle fracture investigations Other brittle fracture investigations, e.g. mechanical fracturing tests [Crack opening displacement (COD) KlC, J-Integral or instrumentation notched bar impact tests] shall be carried out if the results of previous testing indicates they are necessary.

B.4.3 Investigation of behaviour after welding B.4.3.1

Welded joints

If the specified range of the chemical analysis which had been defined during the basic testing will be remarkably changed which might happen during the widening of the production program a new investigation of welded joints in accordance with B.3.11 shall be performed. B.4.3.2

Brittle fracture behaviour of welded joints

If necessary, further investigations shall be performed to determine the brittle fracture behaviour of welded joints. No investigations are necessary for a material thickness < 30 mm. B.4.3.3

Long-term tests

The tests shall be conducted in accordance with B.3.11.2 and B.4.1.1 on welded specimens (heat input l and h, heat treatment conditions a, b and d per annex E). In addition, the hardness (HV 10) shall be determined in the heat affected zone. B.4.3.4

Continuous Cooling Transformation-diagram (CCT-diagram)

In the case of high or multi alloyed steels, the transformation behaviour of which is difficult to estimate (e.g. 12 % chrome-molybdenum-vanadium steel), a CCT-diagram shall be compiled, whereby the T8/5 range should be 5 s to 30 s and the austenitizing temperature ≥ 1 300 °C.

B.5 Collective tests B.5.1 General Collective tests may be executed to satisfy the outstanding necessary investigations by a number of manufacturers in a joint programme.

B.5.2 Fatigue tests Fatigue tests shall be carried out with K = 0 and, as necessary, K = − 1 (K = minimum stress/maximum stress) on 2 steels with a minimum tensile strength > 640 N/mm , whereby testing shall be carried out on three stress levels 6 within the tensile strength range and in addition, the fatigue strength (N = 2 × 10 cycles) shall be determined. Should the material be used exclusively for components for which the number of cycles in the range of their service life-time is known, it will suffice if the tests are based on this number of cycles with an adequate safety factor. Where fatigue testing is carried out on welded test pieces or if the results of corresponding tests carried out elsewhere are available, these investigations of the parent metal may be waived.

25

EN 764-4:2002 (E)

B.5.2.1

Fatigue tests on un-notched specimen

The above mentioned tests shall be carried out on plain specimen. B.5.2.2

Fatigue tests on notched specimen

In order to verify the notch sensitivity, testing may be by: a)

round bar specimen with radius in the notch of R = 0,25 mm; or

b)

flat specimen with a cross-section of 90 mm × 10 mm and a notch of 20 mm depth, 2 mm width and a radius in the notch of R = 1 mm.

B.5.2.3

Fatigue strength of welded joints

Fatigue tests shall be carried out on steels with a minimum tensile strength ≥ 640 N/mm or a minimum yield 2 3 5 strength ≥ 460 N/mm . The tests shall be carried out with K = 0 or if necessary K = − 1 for 10 to 10 cycles whereby five specimen shall be tested for each of three stress levels in the region of the tensile strength. 2

The welding conditions, heat treatment conditions and joint types of Table B.2 are applicable. Table B.2 — Welding conditions, heat treatment conditions and joint types Welding conditions t 8/5 in s

Heat treatment conditions per annex E

Joint type

7

a

1, 2, 3

7

d

2

25

a

2

Key 1

butt welded seam, ground

2

butt welded seam with reinforcement (max. permissible reinforcement h = + 0,10 b)

3

double fillet weld, not ground

Figure B.1 — Butt welded joint

B.5.3 Corrosion behaviour In cases where the resistance to a corrosion mechanism is important, this shall be verified.

26

EN 764-4:2002 (E)

Annex C (normative) Appraisal schedule for austenitic and austenitic-ferritic steels C.1 General The purpose of this annex is to provide a list of properties and test procedures which may be relevant in the characterisation of new "materials" and the determination of material property requirements. For each specific material, the properties to be used as basis for the assessment of the material property requirements shall be selected in accordance with A.5.1.1. The following requirements are valid for austenitic and austenitic-ferritic (Duplex) rolled and forged steels including nickel and nickel-based alloys.

C.2 Test procedures C.2.1 The type and extent of the testing is dependent upon the expected minimum requirements, in considering the processing and use of the product forms and range of dimensions in question. The tests are carried out in the normal delivery condition unless otherwise specified. Test pieces must be taken from upper and lower range of dimensions in accordance with Table C.1. All following testing shall be performed on the base material: 

chemical analysis including accompanying and trace elements in accordance with C.3.2;



tensile tests of the welded joint in accordance with C.3.3;



notched bar impact tests for verifying the heat-affected zone in accordance with C.3.4;



technological tests in accordance with C.3.5;



metallographic investigations in accordance with C.3.6;



testing of the resistance to corrosion in accordance with C.3.7;



long term ageing tests in accordance with C.3.8;



investigation of the effects of cold-forming in accordance with C.3.9.

C.2.2 In the case of the simultaneous appraisal of a number of product forms or thicknesses, the test pieces shall be delected in the way, that they cover the scope proposed for appraisal and the required manufacturing procedures. Endeavours shall be made to select a number of test pieces as low as possible, covering the whole size range (I, II or III, see Table C.1). Normally the following ranges of wall thickness for each product form are applicable as given in Table C.1.

27

EN 764-4:2002 (E)

Table C.1 — Wall thickness for product forms Dimensions in millimetres

Product form Strip Plate Tube Forging/rolled bar

I < 1,5 < 15 < 6 < 25

Ranges of wall thickness II

III

1,5 to 6 15 to 75 6 to 18 25 to 160

> 6 > 75 > 18 > 160

C.2.3 The products to be tested should be at the upper limit of the requested thickness range i.e. not less than 80 % of the proposed maximum thickness. C.2.4 The position from which test pieces shall be removed, unless otherwise specified expressly in the following sections, shall be so arranged, that less favourable areas are also covered by the testing and a good general survey of the uniformity of the product is obtained.

C.3 Basic testing C.3.1 General Basic testing shall be conducted by each material manufacturer on at least two casts, which should cover the specified range of analysis and of the heat treatment.

C.3.2 Determination of the chemical composition The cast analysis shall be given by the material manufacturer. The product analysis shall be carried out on samples to determine all elements given by the material data sheet including accompanying and trace elements.

C.3.3 Tensile tests Tensile tests at room temperature shall be carried out to determine the 0,2 % and 1,0 % proof strength C.3.3.1 (for austenitic-ferritic steels only the 0,2% proof strength), tensile strength, elongation after fracture and yield point ratio on flat test specimen and for product thicknesses > 16 mm, also on round test specimen, whereby the reduction of area is also to be determined. Should it be called for from the manufacturing process or type of material additional tests may be required in the case of plates with thickness > 15 mm on specimen in the thickness direction. Tensile tests (round specimen) shall be carried out at elevated temperatures at intervals of 100 K to C.3.3.2 approximately 50 K above the maximum operating temperature for steels with a guaranteed high temperature yield/tensile strength. The characteristic values to be determined shall be in accordance with C.3.2.1.

C.3.4 Notched-bar impact tests The notched bar impact tests shall be carried out at room temperature and in accordance with B.3 in EN 13445-2:2002 provided for, on Charpy V-notch specimen in accordance with EN 10045. If necessary, impact energy temperature curves (KV-T) shall be produced.

C.3.5 Technological tests According to the form of products, bend tests, flaring tests, flanging tests, ring tensile tests, ring flattening tests, ring expansion tests or other tests appropriate to the material shall be carried out as appropriate with the form concerned. 28

EN 764-4:2002 (E)

C.3.6 Metallographic investigation Metallographic examination shall be carried out to assess the grain size and impurities, intermetallic phases and, as necessary, the delta-ferrite content.

C.3.7 Corrosion tests Where the resistance to intercristalline corrosion is guaranteed, this has to be checked. In the case of stabilized austenites, the lowest possible stabilisation ratio guaranteed by the material manufacturer has to be considered. Limit temperature and service life shall be determined in accordance with C.3.8.2. Where further guarantees have been provided by the material manufacturer in respect of resistance to corrosion (e.g. stress corrosion cracking), these shall be verified under the conditions of the guarantee.

C.3.8 Long term tests Long term tests shall be conducted on high-temperature materials on plain and notched test specimen.

C.3.8.1 NOTE

Further details not considered at present.

Ageing tests shall be carried out over a minimum of 1 000 h, 2 000 h and 5 000 h to determine the C.3.8.2 tendency to precipitation induced embrittlement, if it is expected that such embrittlement may occur in the course of the service life. The estimation of the permissible upper operating temperature or temperature interval can be made if the occasion arise from parametric equations, e.g. in accordance with Larson-Miller: PLM =

T (C + log t)

where C

is the constant (usually C = 20);

T

is the temperature in K;

t

is the time in h.

The testing is carried out on Charpy V-notched specimen in accordance with EN 10045.

C.3.9 Investigation of the effects of cold-forming The influence of cold forming on the grain structure, strength and toughness properties, behaviour in the creep range, guaranteed resistance to corrosion and recrystallization behaviour shall be determined, whereby consideration shall be given to the further processing and operating temperatures provided for and the maximum permissible cold forming without heat treatment shall be ascertained. Specimen are cold formed by straining and pressing respectively.

C.3.10

Investigation of weldablility

The behaviour of the base material shall be investigated for the intended welding procedure, whereby the maximum permissible heat input and operating (interpass) temperature, with consideration of the wall thickness limits, shall be determined. For this purpose, steep bevel seams with max. five degree flange angle shall be welded (see Figure E.1).

C.3.11

Effects of heat treatment after further processing

Should heat treatment be provided for (e.g. solution heat treatment, stress relieving, stabilising annealing), the above mentioned testing shall be conducted, appropriate to the proposed application. The limits for the time/temperature cycles of the heat treatment shall be determined.

29

EN 764-4:2002 (E)

C.4 Sampling C.4.1 Forgings/rolled bar Location of specimen is in accordance with Figure C.1 and Figure C.2. Dimensions in millimetres

main dimension e ≤ 25

main dimension 25 < e ≤ 160

tensile test specimen:

M is the axis of the specimen

notched bar impact specimen: M is the axis of the unnotched specimen

Figure C.1 — Location of the specimens for rolled bar and wire

30

EN 764-4:2002 (E)

Dimensions in millimetres

Figure C.2 — Standard dimensions and specimen locations for bars ≥ 160 mm diameter or thickness and simple forgings

31

EN 764-4:2002 (E)

Table C.2 — Specimen location and direction Dimensions in millimetres

Product

Specimen location and direction

Authoritative dimension

Rolled bar

D/6

Round or

max. 50 mm

diameter or smallest

Rectangular

transverse specimen

length of edge

Disc a 0,1 D ≤ h ≤ D

h/6 and Da/6

Disc with hole 0,1 Da ≤ h ≤ Da

nevertheless cut out of ring

Di ≤ 0,4 Da

tangential specimen

Ring h ≤ Da Di > 0,4 Da

h/6 and s/6, nevertheless max. 50 mm cut out of ring or

Ring h > Da Di > 0,4 Da

cut off from head level of a disc with a hole tangential specimen

a

32

h

smallest dimension from h or s

Discs machined out of rolled bar referring to the authoritative dimension are classified as rolled bar.

s

EN 764-4:2002 (E)

C.4.2 Plate and strip Location of specimen is in accordance with Figure C.3. Conformity with sampling rules in the materials standards is anticipated. Dimensions in millimetres

Key a b c d e

Rolling direction Width of the plate Flat tensile test specimen Notched bar impact test specimen Round tensile test specimen Figure C.3 — Location of specimens for plates and strip 33

EN 764-4:2002 (E)

C.4.3 Tube In the case of tube material, as far as geometrically possible, transverse specimen shall be tested instead of longitudinal specimen. For the tensile tests no round specimens with a diameter less than 8 mm should be used. Tubes with smaller diameter may be tested whole. To proof the uniformity additional specimen shall be tested for every product form at different locations and directions of the test specimen.

C.4.4 Product forms forgings, plate and tube For all product forms according C.4.1, C.4.2, C.4.3 apply: for thickness > 50 mm additionally e/2, > 100 mm additionally e/4 and e/2.

C.4.5 Notched bar In the case of all notched bar impact tests, the notch shall be at right-angles to the rolled surface.

C.4.6 Intercrystalline corrosion Sampling for the testing of resistance to intercrystalline corrosion shall be agreed in accordance with EURONORM 114-72 and C.4.7 respectively.

C.4.7 Testing for resistance to intercrystalline corrosion This test is relevant for a material in the as-welded condition and shall be carried out as follow: a)

for sheet and strip, two sections about 100 mm in length and about 50 mm in width (see Figure C.4); and

b)

for tubes (seamless), two sections about 50 mm in length (see Figure C.5)

shall be joined together by a qualified welding procedure. The form of the seam, the welding process, the weld filler material, welding conditions and heat treatment are accordance with the norm range of application provided for. From these welded components, test specimens accordance with Figure C.4 or Figure C.5 are machined out. Should provision be made for cross-seam welding the fabrication of plates, then the test specimens are prepared from four sections of plate about 50 mm × 50 mm accordance with Figure C.6. The testing of the specimens in conducted in accordance with EURONORM 114-72.

in in in in

Dimensions in millimetres

Figure C.4 — Plate test specimen

34

Figure C.5 — Tube test specimen

EN 764-4:2002 (E)

Figure C.6 — Plate test specimen with cross seam welding

C.5 Extent of testing C.5.1 The tests in accordance with C.3.2, C.3.3.1, C.3.3.2, C.3.4, C.3.5, C.3.6 and C.3.7 shall be conducted for each size range (dimensional limits in accordance with C.2.3 for individual guaranteed values) of every product form. C.5.2 form.

The tests in accordance with C.3.8.2 and C.3.9 shall be carried out for one dimension at every product

C.5.3 In the case of testing in accordance with C.3.10, the identical relevant thickness of a formed product from one cast shall be provided. Normally regarded as relevant thicknesses are the thinnest and the thickest material provided for the welding. The lowest thickness shall be tested every time. For the upper limit, tests which have been carried out on thicknesses > 30 mm are sufficent for a range up to 1,5 times the thickness tested. C.5.4

As a general rule, tests in accordance with C.3.11 are conducted on one cast only.

35

EN 764-4:2002 (E)

Annex D (normative) Appraisal schedule for cast steels D.1 General The purpose of this annex is to provide a list of properties and test procedures which may be relevant in the characterisation of new "materials" and the determination of material property requirements. For each specific material, the properties to be used as basis for the assessment of the material property requirements shall be selected in accordance with A.5.1.1. The following requirements are valid for cast steels.

D.2 Test procedures D.2.1 The type and extent of the testing is dependent upon the expected minimum requirements, in considering the processing and use of the product forms in questions. The tests are carried out in the normal delivery condition unless otherwise specified. The pieces must be taken from upper and lower range of dimensions in accordance with Table C.1. All following testing shall be performed on the base material: 

chemical analysis including accompanying and trace elements in accordance with D.3.2;



tensile tests in accordance with D.3.3;



notched bar impact tests for verifying the heat-affected zone in accordance with D.3.4;



metallographic investigations in accordance with D.3.5;



hardness testing in accordance with D.3.6;



investigation of tempering characteristics in accordance with D.3.7;



determination of transformation behaviour in accordance with D.3.8;



testing of the resistance to corrosion in accordance with D.3.9;



long term ageing tests in accordance with D.3.10;



investigation of weldability in accordance with D.3.11.

D.2.2 In the case of the simultaneous appraisal of a number of product forms or thicknesses, the test pieces shall be selected in the way, that they cover the scope proposed for appraisal and the required manufacturing procedures. Endeavours shall be made to select a number of test pieces as low as possible, covering the whole size range (I, II or III, see Table D.1). Normally the following ranges of wall thickness for each product form are applicable as given in Table D.1.

36

EN 764-4:2002 (E)

Table D.1 — Wall thickness Dimensions in millimetres

Ranges of wall thickness I

II

III

< 25

25 to 160

> 160

D.2.3 Where casting contains more than one thickness range each of these ranges shall be subjected to separate testing. D.2.4 The positions from which test pieces shall be removed, unless otherwise specified expressly in the following sections, shall be so arranged, that less favourable areas are also covered by the testing and a good general survey of the uniformity of the product is obtained. D.2.5

Samples are taken for each casting technique.

D.3 Basic testing D.3.1 General Basic testing shall be conducted by each material manufacturer on at least two casts, which should cover the specified range of analysis and of the heat treatment.

D.3.2 Determination of the chemical composition The cast analysis shall be given by the material manufacturer. The product analysis shall be carried out on samples to determine all fundamental elements and ascertain the segregation behaviour given by the material data sheet.

D.3.3 Tensile tests Tensile tests at room temperature shall be carried out on round test specimens to determine the 0,2 % D.3.3.1 or 1,0 % proof strength, tensile strength, elongation after fracture and reduction of area. Tensile tests (round specimen) shall be carried out at elevated temperatures at intervals of 100 K to D.3.3.2 approximately about 50 K above the maximum operating temperature for steels with a guaranteed high temperature yield/tensile strength. The characteristic values to be determined shall be in accordance with C.3.3.1. D.3.3.3

In the case of low temperature austenitic cast steel, tensile tests shall be carried out on:

a)

plain test specimens at the lowest operating temperature but not lower than − 196 °C, in order to determine the 0,2 % and 1,0 % proof strength, tensile strength, elongation at fracture and reduction area;

b)

plain and notched test specimens with the same area So at the base of the notch, in order to determine the notch tensile ratio. The ratio of maximum edge stress to mean stress shall be at least 4.5. The notch tensile tests shall result in a ratio of Rm notched/Rm plain ≥ 1.

D.3.4 Notched-bar impact tests The notched bar impact tests shall be carried out at room temperature and in accordance with B.3 in EN 13445-2:2002 provided for, on Charpy V-notch specimen in accordance with EN 10045-1. If necessary, impact energy temperature curves (KV-T) shall be produced.

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EN 764-4:2002 (E)

D.3.5 Metallographic investigation Metallographic examination shall be carried out to assess microstructure, grain size and impurities and, as necessary, the delta-ferrite content. In the case of spun-type casts, macro sections shall be produced in addition.

D.3.6 Hardness testing In the case of quenched and tempered materials, a hardness survey shall be carried out to determine homogeneity. The hardenability can be determined by the Jominy test or calculation.

D.3.7 Production of a tempering chart for quenched and tempered and age-hardened steels The tempering characteristic shall be determined for yield strength, tensile strength, yield strength to tensile strength ratio, elongation after fracture, reduction of area and notched bar impact energy at a minimum of five different tempering temperatures above 300 °C and for three tempering times. Temperatures and times should be fixed as to reveal any tendency towards tempering embrittlement and sensitivity to extended times. Tensile tests shall be conducted and impact energy transition curves shall be compiled. According to the results of D.3.4 and D.3.5 the specimen should be selected such that the lowest results can be anticipated.

D.3.8 Determination of the transformation behaviour In order to estimate the transformation behaviour of normalised cast steels the transition points shall be determined by tests. A continuous time-temperature-transformation diagram shall be produced for quenched and tempered or agehardened cast steels.

D.3.9 Corrosion tests Where the resistance to intercristalline corrosion is guaranteed, this shall be checked. In the case of stabilised austenites, the lowest possible stabilisation ratio guaranteed by the material manufacturer shall be considered. Limit temperature and service life shall be determined in accordance with D.3.10.2. Where further guarantees have been provided by the material manufacturer in respect of resistance to corrosion (e.g. stress corrosion cracking), these shall be verified under the conditions of the guarantee.

D.3.10

Long term tests Long term tests shall be conducted on high-temperature materials on plain and notched test speci-

D.3.10.1 mens. NOTE

Further details not considered at present.

Ageing tests shall be carried out over a minimum of 1 000 h, 2 000 h and 5 000 h to determine the D.3.10.2 tendency to precipitation induced embrittlement, if it is expected that such embrittlement may occur in the course of the service life. The estimation of the permissible upper operating temperature can be made if the occasion arise from parametric equations, e.g. in accordance with Larson-Miller: PLM =

t (C + log T)

where

38

C

is the constant (usually C = 20);

T

is the temperature in K,

t

is the time in h.

EN 764-4:2002 (E)

The testing is carried out on Charpy V-notched specimens in accordance with EN 10045-1.

D.3.11

Investigation of weldability

The behaviour of the base material shall be investigated for the intended welding procedure, whereby the maximum permissible heat input and operating (interpass) temperature, with consideration of the wall thickness limits, shall be determined. for this purpose, steep bevel seams with max. 5° flange angle shall be welded (see Figure E.1).

D.3.12

Effects of heat treatment after further processing

Should heat treatment be provided for (e.g. solution heat treatment, stress relieving, stabilising annealing), the above mentioned testing shall be conducted, appropriate to the proposed application. The limits for the time/temperature cycles of the heat treatment shall be determined.

D.4 Sampling D.4.1 the specimens shall be taken in accordance with EN 10213-1 and additionally one specimen taken at mid thickness for wall thicknesses > 50 mm and one specimen at quarter thickness and mid thickness for wall thicknesses > 100 mm. D.4.2

In the case of all notched bar impact tests, the notch shall be perpendicular to the surface.

D.4.3

Sampling for the testing of resistance to intercrystalline corrosion shall be agreed.

D.5 Extent of testing D.5.1 The tests in accordance with D.3.2, D.3.3.1, D.3.3.2, D.3.4; D.3.5 and D.3.6 shall be conducted for each size range (dimensional limits in accordance with D.2.3 for individual guaranteed values) of every product form. D.5.2 In the execution of creep rupture tests in accordance with D.3.10.1, the requirements of EN 10291 shall be noted. D.5.3 form.

The tests in accordance with D.3.10.2 and D.3.11 shall be carried out for one dimension at every product

D.5.4

For the tests in accordance with D.3.3.3 b) one form of product and one cast will suffice.

D.5.5 In the case of testing in accordance with D.3.11, the identical relevant thickness of a product from one cast shall be provided. Normally regarded as relevant thicknesses are the thinnest and the thickest material provided for the welding. The lowest thickness shall be tested every time. For the upper limit, tests which have been carried out on thicknesses > 30 mm are sufficient for a range up to 1,5 times the thickness tested. D.5.6

As a general rule, tests in accordance with D.3.11 are conducted on one cast only.

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EN 764-4:2002 (E)

Annex E (normative) Welding and heat treatment conditions for verification of the weldability of fine-grain steels E.1 General The weldability of the new material shall be qualified by welded specimens. As far as there is no essential change in the analysis within a given thickness range the thickness of the product to be welded should be at the upper limit of the requested thickness range. As for the structure in the HAZ (as well in the filler material) mainly the cooling time t8/5 is relevant, which is defined by the heat input of the welding, the plate thickness and the preheat respectively working temperature, welded joints shall be performed to determine the minimum and maximum t8/5 times; the minimum t8/5 time influences mostly the maximum hardness in the heat affected zone (HAZ) and hereby the probability for cold cracking, the maximum cooling time t8/5 is responsible for a sufficient impact behaviour in the HAZ. NOTE 1

It is recommended to weld joints with cooling times t8/5 between 7 s and 25 s (or 40 s, if appropriate).

NOTE 2 If it is demonstrated e.g. by the cold cracking test that is impossible to keep a cooling time of t8/5 of 7 s then it should be stepwise increased to a higher value of 8 or 9 or 10 s. NOTE 3 If it is foreseen to weld the new material with a high welding heat input a higher cooling time than about 25 s can be used e.g. 40 s. If it becomes evident during the testing of the impact toughness of the HAZ that the impact energy of 27 J respectively 40 J at the temperature which is characteristic for the base material will not be reached the cooling time of 40 s is to be reduced.

E.2 Determination of the cooling time The cooling time t8/5 can be measured, calculated or determined by diagrams in accordance with EN 1011-2, see Figures E.1 to E.3 [13].

Figure E.1 — Plate thickness for the transition from two-dimensional to three-dimensional heat flow, as a function of the heat input and preheat temperature T0 in case of the submerged-arc welding 40

Figure E.2 — Cooling time of beads on plate with three-dimensional heat flow, as a function of the heat input and preheat temperature T0 in case of the submerged-arc welding

EN 764-4:2002 (E)

Figure E.3 — Cooling time of beads on plate with two-dimensional heat flow, as a function of the heat input and preheat temperature T0 in case of the submerged-arc welding

E.3 Heat treatment conditions Table E.1 — Heat treatment conditions Heat treatment condition

a

Welding condition, untreated

b

1 h at Tmin (lowest specified temperature for stress relief)

c

5 h at (Tmin + Tmax)/2

d

15 h at Tmax (highest specified temperature for stress relief)

41

EN 764-4:2002 (E)

Annex F (normative) Metallographic investigation of the sensitivity to stress relief cracking In order to cover the necessary area for the detection of cracking, three separate stages of the tangential section at intervals totalling 0,3 mm to 0,15 mm are generally necessary. The tangential section shall include the top layer, filler layers and root area (see Figure F.1). The overall surface of the section should have dimensions of 50 mm × the product thickness, but not however greater than 50 mm × 50 mm.

Key a b c d e

HAZ Crack susceptible size Base material Layers Centre line of weld Figure F.1 — Tangential section

The location of the section shall be determined by the grain structure in the cross-section and the pattern of the heat-affected zone (HAZ). 42

EN 764-4:2002 (E)

Bibliography [1] Directive 97/23/EC of the European Parliament and of the Council of 29 May 1997 on the approximation of the laws of the Member States concerning pressure equipment [OJEC No L 181, 9 July 1997]. [2] Global Approach to Certification and Testing, published in the "Official Journal of the European Communities" from 89-10-19, No C 267/1 to 27. [3] Guide to the implementation of Community Harmonization Directives based on the new approach and the global approach; first version from February 1993, European Commission, ISBN 92-826-8584-5. [4] AD-Merkblatt W 8, Plattierte Stähle (clad steels); July 1987 [5] Codap, Section M 5: Rules applicable to ferrous and non ferrous cladded metal sheets. [6] SEL 075: Plattierte Erzeugnisse (plated products); February 1993. [7] Sanz G., Rev Metal CIT 1980, pp 621-642. [8] Sandström R., "Minimum usage temperatures for ferritic steels" Scandinavian Journal of Metallurgy 16 (1987), pp 242-252. [9] Garwood S. J. and Denham J. B., 'The fracture toughness requirements of BS 5500', ASME pressure vessel and piping conference (1988), paper 88-PBP-7. [10] 'Guidance on methods for assessing the acceptability of flaws in fusion welded structures', BSI: PD 6493:1991. [11] 'Assessment of the Integrity of Structures Containing Discontinuities', INSTA Technical Report, Materials Standards Institute, Stockholm 1991. [12] Case proposal to EN 13445-2:2002, clause 4.1.6 and annex B, B.3.2 in EN 13445-2:2002 (prepared by SG Low Temperature), document CEN/TC 54/267/JWG B N 400. [13] EN 287-1, Approval testing of welders — Fusion welding — Part 1: Steels. [14] EN 288-1, Specification and qualification of welding procedures for metallic material — Part 1: General rules for fusion welding. [15] EN 288-2, Specification and qualification of welding procedures for metallic material — Part 2: Welding procedure specification for arc welding. [16] EN 1252-2, Cryogenic vessels — Materials — Part 2: Toughness requirements for the temperature between − 80 °C and − 20 °C. [17] EN 10164, Steel products with improved deformation properties perpendicular to the surface of the product — Technical delivery conditions. [18] prEN 12074, Welding consumables — Quality requirements for manufacture, supply and distribution of consumables for welding and allied processes. [19] ENV 22605-1, Steel products for pressure purposes — Derivation and verification of elevated temperature properties — Part 1: Yield or proof stress of carbon and low alloy steel products (ISO 2605-1:1976). [20] ENV 22605-2, Steel products for pressure purposes — Derivation and verification of elevated temperature properties — Part 2: Proof stress of austenitic steel products (ISO 2605-2:1976). [21] ENV 22605-3, Steel products for pressure purposes — Derivation and verification of elevated temperature properties — Part 3: An alternative procedure for deriving the elevated temperature yield of proof stress properties when data are limited (ISO 2605-3:1985). 43

EN 764-4:2002 (E)

[22] EN ISO 3690, Welding and allied processes — Determination of hydrogen content in ferritic arc weld metal. [23] EN ISO 377, Steel and steel products — Location of samples and test pieces for mechanical testing (ISO 377:1997). [24] EN ISO 642:1999, Steel — Hardenability test by end quenching (Jominy test) (ISO 642:1999).

[25] EN 764-5, Pressure equipment — Part 5: Compliance and Inspection Documentation of Materials.

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