Unfired pressure vessels - Part 2: Materials

This document specifies the requirements for steel products used for unfired pressure vessels.
For some metallic materials other than steel, such as spheroidal graphite cast iron, aluminium, nickel,
copper, titanium, requirements are or will be formulated in separate parts of this document.
For metallic materials which are not covered by a harmonized material standard and are not likely to be
in near future, specific rules are given in this part or the above cited parts of this document.

Unbefeuerte Druckbehälter - Teil 2: Werkstoffe

Diese Europäische Norm legt die Anforderungen an Stahlerzeugnisse für unbefeuerte Druckbehälter fest.
Für einige metallische Werkstoffe außer Stahl, z. B. Gusseisen mit Kugelgraphit, Aluminium, Nickel, Kupfer, Titan, sind oder werden die Anforderungen in weiteren Teilen dieser Europäischen Norm festgelegt.
Für metallische Werkstoffe, die nicht in harmonisierten Werkstoffnormen enthalten sind und es auch in naher Zukunft nicht sein werden, sind spezielle Regeln in diesem Teil oder in den oben genannten Teilen dieser Europäischen Norm enthalten.

Récipients sous pression non soumis à la flamme - Partie 2: Matériaux

Nekurjene tlačne posode - 2. del: Materiali

General Information

Status
Published
Publication Date
19-Aug-2021
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
29-Jun-2021
Due Date
03-Sep-2021
Completion Date
20-Aug-2021

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SLOVENSKI STANDARD
SIST EN 13445-2:2021
01-september-2021
Nadomešča:
SIST EN 13445-2:2014
SIST EN 13445-2:2014/A1:2017
SIST EN 13445-2:2014/A2:2018
SIST EN 13445-2:2014/A3:2018
Nekurjene tlačne posode - 2. del: Materiali
Unfired pressure vessels - Part 2: Materials
Unbefeuerte Druckbehälter - Teil 2: Werkstoffe
Récipients sous pression non soumis à la flamme - Partie 2: Matériaux
Ta slovenski standard je istoveten z: EN 13445-2:2021
ICS:
23.020.32 Tlačne posode Pressure vessels
SIST EN 13445-2:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 13445-2:2021
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SIST EN 13445-2:2021
EN 13445-2
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2021
EUROPÄISCHE NORM
ICS 23.020.30 Supersedes EN 13445-2:2014
English Version
Unfired pressure vessels - Part 2: Materials

Récipients sous pression non soumis à la flamme - Unbefeuerte Druckbehälter - Teil 2: Werkstoffe

Partie 2: Matériaux
This European Standard was approved by CEN on 24 February 2021.

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 CEN-CENELEC 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 CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13445-2:2021 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
Contents
Page

European foreword ....................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms, definitions, symbols and units .................................................................................................... 7

3.1 Terms and définitions ................................................................................................................................... 7

3.2 Symbols and units ........................................................................................................................................... 9

4 Requirements for materials to be used for pressure-bearing parts ......................................... 11

4.1 General ............................................................................................................................................................. 11

4.2 Special provisions ........................................................................................................................................ 13

4.2.1 Special properties ........................................................................................................................................ 13

4.2.2 Design temperature above 20 °C ............................................................................................................ 13

4.2.3 Prevention of brittle fracture .................................................................................................................. 14

4.2.4 Design properties in the creep range ................................................................................................... 14

4.2.5 Specific requirements for steels for fasteners ................................................................................... 14

4.3 Technical delivery conditions ................................................................................................................. 15

4.3.1 European Standards .................................................................................................................................... 15

4.3.2 European Approval for Materials ........................................................................................................... 15

4.3.3 Particular material appraisals ................................................................................................................ 15

4.3.4 Clad products ................................................................................................................................................. 15

4.3.5 Welding consumables ................................................................................................................................. 15

4.4 Marking ............................................................................................................................................................ 15

5 Requirements for materials to be used for non-pressure parts ................................................. 16

(normative) Grouping system for steels for pressure equipment ......................................... 17

(normative) Requirements for prevention of brittle fracture at low temperatures ....... 19

B.1 General ............................................................................................................................................................. 19

B.2 Material selection and impact energy requirements ...................................................................... 20

B.2.1 Introduction ................................................................................................................................................... 20

B.2.2 Method 1 .......................................................................................................................................................... 20

B.2.3 Method 2 .......................................................................................................................................................... 30

B.2.4 Method 3 — Fracture mechanics analysis ........................................................................................... 42

B.3 General test requirements ........................................................................................................................ 43

B.3.1 General ............................................................................................................................................................. 43

B.3.2 Sub-sized specimens ................................................................................................................................... 44

B.4 Welds ................................................................................................................................................................ 45

B.4.1 General ............................................................................................................................................................. 45

B.4.2 Welding procedure qualification ........................................................................................................... 45

B.4.3 Production test plates ................................................................................................................................ 45

B.5 Materials for use at elevated temperatures ....................................................................................... 45

B.5.1 General ............................................................................................................................................................. 45

B.5.2 Materials .......................................................................................................................................................... 46

B.5.3 Welding procedure qualification and production test plates ...................................................... 46

B.5.4 Start up and shut down procedure ........................................................................................................ 46

B.5.5 Pressure test .................................................................................................................................................. 46

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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
(informative) Procedure for determination of the weld creep strength reduction

factor (WCSRF) .............................................................................................................................................. 54

(informative) Technical delivery conditions for clad products for pressure

purposes .......................................................................................................................................................... 55

D.1 Introductory note ......................................................................................................................................... 55

D.2 Requirements for the material ................................................................................................................ 55

D.3 Requirements for the deposited material ........................................................................................... 55

D.4 Qualification of the cladding procedure ............................................................................................... 56

D.5 Production tests ............................................................................................................................................ 57

(informative) European steels for pressure purposes ................................................................ 59

E.1 European Standards for steels and steel components for pressure purposes ....................... 59

E.2 European standardised steels grouped according to product forms ........................................ 60

(normative) Special provisions for materials and components .............................................. 83

F.1 General ............................................................................................................................................................. 83

F.2 Mechanical properties and technical delivery conditions for fasteners in accordance

with EN ISO 3506 ........................................................................................................................................... 83

F.2.1 Mechanical properties for austenitic bolts in accordance with EN ISO 3506-1 ..................... 83

F.2.2 Delivery conditions for austenitic fasteners....................................................................................... 84

(informative) History of EN 13445-2 ................................................................................................. 85

Y.1 Differences between EN 13445-2:2014 and EN 13445-2:2021.................................................... 85

Annex ZA (informative) Relationship between this European Standard and the essential

requirements of Directive 2014/68/EU aimed to be covered ..................................................... 86

Bibliography ................................................................................................................................................................. 87

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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
European foreword

This document (EN 13445-2:2021) 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 November 2021, and conflicting national standards shall

be withdrawn at the latest by November 2021.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document has been prepared under a standardization request given to CEN by the European

Commission and the European Free Trade Association, and supports essential requirements of

EU Directive(s).

For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this

document.
list of all parts in the EN 13445 series can be found on the CEN website.

Although these Parts may be obtained separately, it should be recognised that the Parts are inter-

dependant. As such the manufacture of unfired pressure vessels requires the application of all the

relevant Parts in order for the requirements of the Standard to be satisfactorily fulfilled.

Corrections to the standard interpretations where several options seem possible are conducted through

the Migration Help Desk (MHD). Information related to the Help Desk can be found at http://www.unm.fr

(en13445@unm.fr). A form for submitting questions can be downloaded from the link to the MHD

website. After subject experts have agreed an answer, the answer will be communicated to the

questioner. Corrected pages will be given specific issue number and issued by CEN according to CEN

Rules. Interpretation sheets will be posted on the website of the MHD.

This document supersedes EN 13445-2:2014. This new edition incorporates the Amendments which

have been approved previously by CEN members, and the corrected pages up to Issue 5 without any

further technical change. Annex Y provides details of significant technical changes between this European

Standard and the previous edition.

Amendments to this new edition may be issued from time to time and then used immediately as

alternatives to rules contained herein. It is intended to deliver a new Issue of EN 13445:2021 each year,

starting with the precedent as Issue 1, consolidating these Amendments and including other identified

corrections.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,

Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France,

Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands,

Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

the United Kingdom.
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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
1 Scope

This document specifies the requirements for steel products used for unfired pressure vessels.

For some metallic materials other than steel, such as spheroidal graphite cast iron, aluminium, nickel,

copper, titanium, requirements are or will be formulated in separate parts of this document.

For metallic materials which are not covered by a harmonized material standard and are not likely to be

in near future, specific rules are given in this part or the above cited parts of this document.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

EN 764-1:2015+A1:2016, Pressure equipment — Terminology — Part 1: Pressure, temperature, volume,

nominal size
EN 764-2:2012, Pressure equipment — Part 2: Quantities, symbols and units
EN 764-3:2002, Pressure equipment — Part 3: Definition of parties involved

EN 764-4:2014, Pressure equipment — Part 4: Establishment of technical delivery conditions for metallic

materials

EN 764-5:2014, Pressure equipment — Part 5: Inspection documentation of metallic materials and

compliance with the material specification

EN 1092-1:2018, Flanges and their joints — Circular flanges for pipes, valves, fittings and accessories, PN

designated — Part 1: Steel flanges

EN 10028-2:2009, Flat products made of steels for pressure purposes — Part 2: Non-alloy and alloy steels

with specified elevated temperature properties

EN 10028-3:2009, Flat products made of steels for pressure purposes — Part 3: Weldable fine grain steels,

normalized

EN 10028-4:2009, Flat products made of steels for pressure purposes — Part 4: Nickel alloy steels with

specified low temperature properties

EN 10028-5:2009, Flat products made of steels for pressure purposes — Part 5: Weldable fine grain steels,

thermomechanically rolled

EN 10028-6:2009, Flat products made of steels for pressure purposes — Part 6: Weldable fine grain steels,

quenched and tempered

EN 10028-7:2007, Flat products made of steels for pressure purposes — Part 7: Stainless steels

EN 10204:2004, Metallic products — Types of inspection documents
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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)

EN 10216-3:2013, Seamless steel tubes for pressure purposes — Technical delivery conditions — Part 3:

Alloy fine grain steel tubes

EN 10216-4:2013, Seamless steel tubes for pressure purposes — Technical delivery conditions — Part 4:

Non-alloy and alloy steel tubes with specified low temperature properties

EN 10217-3:2002, EN10217-3:2002/A1:2005, Welded steel tubes for pressure purposes — Technical

delivery conditions — Part 3: Alloy fine grain steel tubes

EN 10217-4:2002, EN 10217-4:2002/A1:2005, Welded steel tubes for pressure purposes — Technical

delivery conditions — Part 4: Electric welded non-alloy steel tubes with specified low temperature

properties

EN 10217-6:2002, EN 10217-6:2002/A1:2005, Welded steel tubes for pressure purposes — Technical

delivery conditions — Part 6: Submerged arc welded non-alloy steel tubes with specified low temperature

properties

EN 10222-3:1998, Steel forgings for pressure purposes — Part 3: Nickel steels with specified low

temperature properties

EN 10222-4:1998, EN 10222-4:1998/A1:2001, Steel forgings for pressures purposes — Part 4: Weldable

fine grain steels with high proof strength

EN 10269:2013, Steels and nickel alloys for fasteners with specified elevated and/or low temperature

properties

EN 10273:2007, Hot rolled weldable steel bars for pressure purposes with specified elevated temperature

properties

EN 12074:2000, Welding consumables — Quality requirements for manufacture, supply and distribution of

consumables for welding and allied processes
EN 13445-1:2021, Unfired pressure vessels — Part 1: General
EN 13445-3:2021, Unfired pressure vessels — Part 3: Design
EN 13445-4:2021, Unfired pressure vessels — Part 4: Fabrication
EN 13445-5:2021, Unfired pressure vessels — Part 5: Inspection and testing

EN 13479:2004, Welding consumables — General product standard for filler metals and fluxes for fusion

welding of metallic materials

EN ISO 148-1:2010, Metallic materials — Charpy pendulum impact test — Part 1: Test method (ISO 148-

1:2010)

EN ISO 204:2009, Metallic materials — Uniaxial creep testing in tension — Method of test (ISO 204:2009)

EN ISO 898-1:2013, Mechanical properties of fasteners made of carbon steel and alloy steel — Part 1: Bolts,

screws and studs with specified property classes — Coarse thread and fine pitch thread (ISO 898-1:2013)

EN ISO 898-2:2012, Mechanical properties of fasteners made of carbon steel and alloy steel — Part 2: Nuts

with specified property classes — Coarse thread and fine pitch thread (ISO 898-2:2012)

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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)

EN ISO 2566-1:1999, Steel — Conversion of elongation values — Part 1: Carbon and low alloy steels

(ISO 2566-1:1984)

EN ISO 2566-2:1999, Steel — Conversion of elongation values — Part 2: Austenitic steels (ISO 2566-

2:1984)

EN ISO 3506-1:2009, Mechanical properties of corrosion-resistant stainless-steel fasteners — Part 1: Bolts,

screws and studs (ISO 3506- 1:2009)

EN ISO 3506-2:2009, Mechanical properties of corrosion-resistant stainless-steel fasteners — Part 2: Nuts

(ISO 3506-2:2009)

EN ISO 6892-1:2009, Metallic materials — Tensile testing — Part 1: Method of test at room temperature

(ISO 6892-1:2009)

CEN ISO/TR 15608:2000, Welding — Guidelines for a metallic material grouping system

(ISO/CR 15608:2000)
3 Terms, definitions, symbols and units
3.1 Terms and définitions

For the purposes of this document, the terms and definitions given in EN 13445-1:2021, EN 764-

1:2015+A1:2016, EN 764-3:2002 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
minimum metal temperature T

the lowest temperature determined for any of the following conditions (also see 3.1.2, 3.1.3):

— normal operations;
— start up and shut down procedures;

— possible process upsets, such as flashings of fluid, which have an atmospheric boiling point below

0 °C;
— during pressure or leak testing.
3.1.2
temperature adjustment term T

relevant to the calculation of the design reference temperature T and is dependent on the calculated

tensile membrane stress at the appropriate minimum metal temperature
Note 1 to entry: Values for TS are given in Table B.2-12.

Note 2 to entry: For tensile membrane stress reference is made to EN 13445-3:2021, Annex C.

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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
3.1.3
design reference temperature T

the temperature used for determining the impact energy requirements and is determined by adding the

temperature adjustment T to the minimum metal temperature T :
S M
T = T + T
R M S
3.1.4
impact test temperature TKV

the temperature at which the required impact energy has to be achieved (see B.2).

3.1.5
impact energy KV

the energy absorbed by a sample of material when subjected to a Charpy-V-notch test in accordance with

EN ISO 148-1:2010
3.1.6
reference thickness e

thickness of a component to be used to relate the design reference temperature T of the component with

its required impact test temperature TKV, (see Tables B.2-2 to B.2-7 and Figures B.2-1 to B.2-11). For

unwelded parts the reference thickness e is equal to the nominal wall thickness (including corrosion

allowance). For welded parts the reference thickness is defined in Table B.4-1.
3.1.7
weld creep strength reduction factor (WCSRF)
factor to account for creep strength reduction at the weldment
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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
3.2 Symbols and units

For the purpose of this part, the symbols and units of EN 764-2:2012 apply together with those given in

Table 3.2-1 and Table 3.2-2.
Table 3.2-1 — Quantities for space and time
Quantity Symbol Unit
time t s, min, h, d, a
frequency f Hz
any Latin letter a
dimension mm
length l mm
thickness e mm
corrosion allowance c mm
diameter d, D mm
radius r, R mm
area A, S mm
b, c
volume, capacity V mm
weight W N, kN
density kg/mm
second moment of area mm
section modulus Z mm
acceleration m/s
any Greek letter
plane angle rad, °

Symbols may use any lower-case letter, except for those defined elsewhere in this table.

Volume may also be given in m or L.
Litre "L" is a non-SI unit which may be used with SI units and their multiples.
Density may also be given in kg/m .
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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
Table 3.2-2 — Mechanical quantities
a b
Symbol Unit
Quantity
force F N
moment M .
N mm
pressure p, P bar , MPa
Temperature T °C
linear expansion coefficient α µm/m°C
normal stress σ MPa
shear stress MPa
nominal design stress f MPa
tensile strength R MPa
ultimate tensile strength at temperature T R MPa
m/T
yield strength R MPa
yield strength at temperature T R MPa
e/T
upper yield strength R MPa
1 % proof strength R MPa
p1,0
0,2 % proof strength R MPa
p0,2
0,2 % proof strength at temperature T R MPa
p0,2/T
modulus of elasticity E MPa
shear modulus G MPa
Poisson's ratio –
strain ε %
elongation after fracture A %
impact energy KV J
hardness HB, HV –
Joint coefficient z –
safety factor S –
Mean 1 % creep strain limit at calculation MPa
p1,0/T/t
temperature T and lifetime t
Mean creep rupture strength at calculation MPa
m/T/t
temperature T and lifetime t
Weld creep strength reduction factor z -
Quantities without a temperature index normally refer to room temperature.
Some of these symbols, such as R, f, are not part of ISO 31.

"bar" is a non-SI unit which may be used with SI units and their multiples. The unit bar shall be used on nameplates,

certificates, drawings, pressure gauges and instrumentation and is always used as a gauge pressure. This is in line with

the requirements of the Pressure Equipment Directive 97/23/EC.
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SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
4 Requirements for materials to be used for pressure-bearing parts
4.1 General

4.1.1 Materials to be used for pressure-bearing parts shall meet the general requirements of 4.1 and the

special provisions of 4.2, if applicable. Materials for pressure bearing parts shall be ordered complying

with the technical delivery conditions in 4.3.

Marking of materials for pressure-bearing parts shall be performed in accordance with 4.4.

Materials shall be selected to be compatible with anticipated fabrication steps and to be suitable for the

internal fluid and external environment. Both normal operating conditions and transient conditions

occurring during fabrication transport, testing and operation shall be taken into account when specifying

the materials.

NOTE 1 The requirements of 4.1 and 4.2 should also be fulfilled when technical delivery conditions are

developed for European material standards, European approval of materials or particular material appraisals.

NOTE 2 When technical delivery conditions for pressure-bearing parts are developed, the structure and

requirements of EN 764-4:2014 should be met. Exceptions should be technically justified.

The materials shall be grouped in accordance with CEN ISO/CR 15608:2000 to relate manufacturing and

inspection requirements to generic material types.

NOTE 3 Materials have been allocated into these groups in accordance with their chemical composition and

properties in view of manufacture and heat treatment after welding.

4.1.2 Materials for pressure-bearing parts compliant with the requirements of this document shall be

accompanied by inspection documents in accordance with EN 10204:2004. Certificate of specific control

(3.1 or 3.2 certificate) shall be required for all steels if Design by Analysis – Direct Route according to

Annex B of EN 13445-3:2021 is used.

The type of inspection document shall be in accordance with EN 764-5:2014 and include a declaration of

compliance to the material specification.

4.1.3 The materials shall be free from surface and internal defects which can impair their intended

usability.

4.1.4 Steels shall have a specified minimum elongation after fracture measured on a gauge length

L = 5,65 S (4.1-1)
o o
where
S is the original cross sectional area within the gauge length.
The minimum elongation after fracture in any direction shall be ≥ 14 %.

When measured on a gauge length other than that stated here, the minimum elongation after fracture

shall be determined by converting the elongation in accordance with
— EN ISO 2566-1:1999 for carbon and low alloy steels;
---------------------- Page: 13 ----------------------
SIST EN 13445-2:2021
EN 13445-2:2021 (E)
Issue 1 (2021-05)
— EN ISO 2566-2:1999 for austenitic steels.

4.1.5 However, lower elongation values may also be applied (e.g. for fasteners or castings), provided

that appropriate measures are taken to compensate for these lower values and the specific requirements

are verifiable.
NOTE Examples for compensation:
— application of higher safety factors in design;
— performance of burst tests to demonstrate ductile material behaviour.

4.1.6 Steels shall have a specified minimum impact energy measured on a Charpy-V-notch impact test

specimen (EN ISO 148-1:2010) as follows:
— ≥ 27 J for
...

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