SIST EN 13445-1:2021

SLOVENSKI STANDARD
SIST EN 13445-1:2021
01-september-2021
Nadomešča:
SIST EN 13445-1:2014
SIST EN 13445-1:2014/A1:2015
SIST EN 13445-1:2014/A2:2018
Nekurjene tlačne posode - 1. del: Splošno
Unfired pressure vessels - Part 1: General
Unbefeuerte Druckbehälter - Teil 1: Allgemeines
Récipients sous pression non soumis à la flamme - Partie 1: Généralités
Ta slovenski standard je istoveten z: EN 13445-1:2021
ICS:
23.020.32 Tlačne posode Pressure vessels
SIST EN 13445-1:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 13445-1:2021

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SIST EN 13445-1:2021


EN 13445-1
EUROPEAN STANDARD

NORME EUROPÉENNE

May 2021
EUROPÄISCHE NORM
ICS 23.020.30 Supersedes EN 13445-1:2014
English Version

Unfired pressure vessels - Part 1: General
Récipients sous pression non soumis à la flamme - Unbefeuerte Druckbehälter - Teil 1: Allgemeines
Partie 1: Généralités
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 13445-1:2021 E
worldwide for CEN national Members.

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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
Contents
Page
European foreword . 3
Introduction . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Interdependency of the parts of the series . 9
5 Quantities, symbols and units . 9
6 Risk assessment and handling . 12
(informative) Using the standard . 14
(informative) Index . 28
(informative) List of Essential Safety Requirements . 49
(informative) History of EN 13445-1 . 56
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Directive 2014/68/EU aimed to be covered . 57
Bibliography . 58



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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
European foreword
This document (EN 13445-1:2021) 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.
The 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 13445-1:2014. 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 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
Introduction
EN 13445 specifies the requirements for design, construction, inspection and testing of unfired pressure
vessels. It defines terms, definitions and symbols applicable to unfired pressure vessels.
NOTE In EN 13445 the term pressure vessel includes the welded attachments up to and including the nozzle
flanges, screwed or welded connections, or the edge to be welded at the first circumferential weld at connecting
piping or other elements. The term unfired excludes vessels that are subject to direct generated heat or flame
impingement from a fired process. This does not exclude vessels subject to electrical heating or heated process
streams.
In Parts 2 to 5 only pressure vessels manufactured from steels and steel castings as detailed in Part 2 of
this standard are covered. Parts 6, 8, and 10 specifically deal with vessels of spheroidal graphite cast iron,
aluminium, and nickel, respectively, where special considerations apply.
Part 1
This part contains general information on the scope of the standard as well as terms, definitions,
quantities, symbols and units which are applied throughout the standard.
Part 2
This part deals with the general philosophy on materials, material grouping and low temperature
behaviour. It is limited to steel with sufficient ductility and, for components operating in the creep range,
sufficient creep ductility.
Part 2 also provides the general requirements for establishing technical delivery conditions and the
requirements for marking of material.
Part 3
This part of the standard gives the rules to be used for design and calculation under internal and/or
external pressure (as applicable), local loads and actions other than pressure. The rules provided are both
design by formulae (DBF), design by analysis (DBA) and design by experiment (DBE).
The part also sets the requirements for when fatigue analysis must be performed and the rules to be
followed when this is the case.
NOTE Collaborative work is in hand to harmonize flange design across European standards.
Part 4
This part of the standard specifies requirements for the manufacture of unfired pressure vessels and their
connections to non-pressure parts. It specifies requirements for material traceability, manufacturing
tolerances, welding requirements, requirements for permanent joints other than welding, production
tests, forming requirements, heat treatment, repairs and finishing operations.
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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
Part 5
This part covers all those inspection and testing activities associated with the verification of the pressure
vessel for compliance with the standard, including design review by the manufacturer and supporting
technical documentation, NDT and other inspection activities including document control, material
traceability, joint preparation and welding.
The level of testing is driven by the selection of the vessel testing group. Basically, the testing group
determines the level of NDT and the joint coefficient used in the design.
In terms of NDT, the overall philosophy has been the general adoption of EN ISO 5817:2014 quality level
'C' for predominantly non-cyclic loaded vessels and level 'B' for vessels subject to cyclic loadings.
Part 6
This part contains special rules for material, design, fabrication, inspection, and testing of pressure
vessels made from spheroidal graphite cast iron. In general the rules in the relevant parts of parts 2–5
apply with additions and exceptions outlined in this part.
Part 7
This part gives guidance on how to use the conformity assessment procedures in the Pressure Equipment
Directive 97/23/EC. This is a CEN Technical Report.
Part 8
This part contains special rules for material, design, fabrication, inspection, and testing of pressure
vessels made from aluminium and aluminium alloys. In general the rules in the relevant parts of parts 2–
5 apply with additions and exceptions outlined in this part.
Part 9
This part details the conformance of the whole EN 13445 series to ISO 16528-1 "Boilers and pressure
vessels — Part 1: Performance requirements". This is a CEN Technical Report. The first edition is limited
to vessels of steel construction, but will be amended later to include spheroidal graphite cast iron and
aluminium.
Part 10
This part 10 contains special rules for material, design, fabrication, inspection, and testing of pressure
vessels made from nickel and nickel alloys. In general, the rules in the relevant parts of parts 2–5 apply
with additions and exceptions outlined in this part.
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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
1 Scope
This document defines the terms, definitions, quantities, symbols and units that are used throughout the
EN 13445 series and gives general information on the design and manufacturing of vessels under this
standard.
It also contains instructions on how to use the standard (Annex A) as well as an index which covers the
whole standard (Annex B). This information is aimed to aid users of the EN 13445 series.
This document applies to unfired pressure vessels with a maximum allowable pressure greater than
0,5 bar gauge but may be used for vessels operating at lower pressures, including vacuum.
This document is not applicable to pressure vessels of the following types:
— vessels of riveted construction;
— vessels of lamellar cast iron or any other materials not included in Parts 2, 6, or 8 of the standard;
— multilayered, autofrettaged or pre-stressed vessels.
This document can be applied to the following pressure vessels, provided that account is taken of
additional and/or alternative requirements resulting from the hazard analysis and from rules or
instructions specific for:
— transportable vessels;
— items specifically designed for nuclear use;
— pressure vessels with a risk of overheating.
NOTE EN 14222 covers electrically fired boilers made from stainless steel and can be used as an example of
additional requirements for such vessels.
Other European standards apply to industrial piping (EN 13480 series) and to water tube and shell
boilers (EN 12952 series and EN 12953 series).
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 — Part 1: Vocabulary
EN 764-2:2012, Pressure equipment — Part 2: Quantities, symbols and units
EN 13445-2:2021, Unfired pressure vessels — Part 2: Materials
EN 13445-3:2021, Unfired pressure vessels — Part 3: Design
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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
EN 13445-4:2021, Unfired pressure vessels — Part 4: Fabrication
EN 13445-5:2021, Unfired pressure vessels — Part 5: Inspection and testing
EN 13445-6:2021, Unfired pressure vessels — Part 6: Requirements for the design and fabrication of
pressure vessels and pressure parts constructed from spheroidal graphite cast iron
EN 13445-8:2021, Unfired pressure vessels — Part 8: Additional requirements for pressure vessels of
aluminium and aluminium alloys
EN 13445-10:2021, Unfired pressure vessels — Part 10 Additional requirements for pressure vessels of
nickel and nickel alloys
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 764-1:2015+A1:2016,
EN 764-2:2012 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
NOTE To aid the user, some of the most important terms and definitions from EN 764-1 have been repeated
here.
3.1
assembly
several pieces of pressure equipment assembled by a manufacturer to constitute an integrated and
functional whole
3.2
fluid
gas, liquid and vapour in their pure phase as well as mixtures thereof
Note 1 to entry: A fluid may contain a suspension of solids.
3.3
hazard
potential source of harm
3.4
hazard category
category of the pressure vessel taking into account the potential hazards
3.5
joint coefficient
reduction coefficient, which is applied to the nominal design stress
Note 1 to entry: E.g. used for a welded joint and related to the testing group.
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EN 13445-1:2021 (E)
Issue 1 (2021-05)
3.6
main pressure bearing parts
parts which constitute the envelope under pressure, essential for the integrity of the equipment
3.7
manufacturer
individual or organization responsible for the design, fabrication, testing, installation where relevant, and
compliance with the requirements of the relevant product standard, whether executed by him or a
subcontractor
Note 1 to entry: The manufacturer can subcontract one or more of the above mentioned tasks under its
responsibility.
3.8
material manufacturer
individual or organization that produces material in the basic product form used in the manufacture of
pressure components
3.9
maximum allowable pressure
PS
maximum pressure for which the pressure vessel is designed as specified by the manufacturer
3.10
maximum allowable temperature
TS
max
maximum temperature for which the pressure vessel is designed as specified by the manufacturer
3.11
minimum allowable temperature
TS
min
minimum temperature for which the pressure vessel is designed as specified by the manufacturer
3.12
pipelines
piping or system of piping designed for the conveyance of any fluid or substance to or from an installation
(onshore or offshore) starting from and including the first isolation device located within the installation
and including all the annexed equipment designed specifically for pipelines
3.13
piping
tubing, fittings, expansion joints, hoses or other pressure-bearing components, intended for the transport
of fluid, connected together and integrated into a pressure system
3.14
pressure vessel
housing and its direct attachments up to the coupling point connecting it to other equipment, designed
and built to contain fluids under pressure
Note 1 to entry: A vessel may be composed of more than one chamber.
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EN 13445-1:2021 (E)
Issue 1 (2021-05)
3.15
required thickness
thickness excluding corrosion or any other allowances specified in the EN 13445 series
Note 1 to entry: The minimum thickness that the component can have in service to fulfil the standard.
3.16
risk
combination of the probability of occurrence of harm and the severity of that harm
3.17
significant hazard
hazard which has been identified as associated with the pressure vessel and which requires specific
action by the designer to eliminate or to reduce the risk according to the risk assessment
3.18
testing factor
reduction factor taking into account the amount of NDT testing in castings, applied on the nominal design
stress to take account of possible manufacturing deficiencies
3.19
testing group
grouping which determines the appropriate level of non-destructive testing (NDT) on a welded joint
Note 1 to entry: The testing group of a vessel is not linked to the hazard category.
3.20
weldment
weld metal, heat affected zone and adjacent base material(s)
4 Interdependency of the parts of the series
Parts 2 to 6 and parts 8 and 10 of EN 13445, together with Part 1, form a consistent set of specifications
which shall be followed for compliance to the standard.
NOTE Parts 7 and 9 of this series are published as a CEN Report and a CEN Technical Report respectively. They
are not European Standards.
5 Quantities, symbols and units
Quantities, symbols and units to be used for pressure equipment shall be in accordance with Tables 5-1
and 5-2 and EN 764-2:2012
NOTE 1 Other symbols used in specific parts of this document are tabulated in the relevant part.
NOTE 2 The choice of the appropriate multiple (decimal multiple or sub-multiple) of a unit is governed by
convenience, the multiple chosen for a particular application being one which should lead to numerical values
within a practical range. Therefore when indicating quantities it is recommended that decimal multiple or sub-
multiple quantities be chosen such that the resulting values are easy to handle, e.g. between 0,1 and 1 000. The non-
SI units, bar for pressure and L for volume should be used on the nameplate.
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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
Table 5-1 — Quantities for space and time
Quantity Symbol Unit
Time t s, min, h
Frequency f Hz
a
any Latin letter
Dimension mm

Length l mm
Thickness e mm
Corrosion allowance c mm
Diameter d, D mm
Radius r, R mm
2
Area A, S mm
b c
3
Volume, capacity V
mm
Weight W N, kN
d
3
Density ρ kg/mm
4
Second moment of area mm
Ι
3
Section modulus Z mm
2
Acceleration m/s
γ
a
any Greek letter
Plane angle rad, °

a

Symbols may use any lower-case letter, except for those defined elsewhere in this table.
b
3
volume may also be given in m or L.
c
litre "L" is a non-SI unit which may be used with SI units and their multiples.
d
3
Density may also be given in kg/m .

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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
Table 5-2 — Mechanical quantities
a
b
Symbol Unit
Quantity
Force F N
Moment M .
N mm
c
Pressure p, P bar , MPa
Temperature T °C
Linear expansion coefficient α µm/m°C
Normal stress MPa
σ
Shear stress MPa
τ
Nominal design stress f MPa
Tensile strength R MPa
m
Yield strength R MPa
e
1 % proof strength Rp1.0 MPa
Proof strength at temperature T R MPa
p/T
Upper yield strength R MPa
eH
0,2 % proof strength R MPa
p0,2
0,2 % proof strength at temperature T R MPa
p0,2/T
Ultimate tensile strength at temperature T R MPa
m/T
Modulus of elasticity E MPa
Shear modulus G MPa
Poisson's ratio υ -
Strain ε %
Elongation after rupture/fracture A %
Impact energy KV J
Hardness HB,HV -
Joint coefficient z -
Safety factor S -
a

Quantities without a temperature index normally refer to room temperature.
b
Some of these symbols, such as R, f, are not part of ISO 31.
c
 "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 2014/68/EU.
NOTE The use of symbols for temperature may be different from the PED.

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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)
6 Risk assessment and handling
6.1 Hazards
Pressure vessels according to this document shall be designed, constructed, installed and equipped under
consideration of all significant hazards and risks that may arise when the vessel is erected, tested and
operated in accordance with the manufacturer’s instructions or else are reasonably foreseeable.
Such hazards shall be analysed by the manufacturer prior to designing the vessel. Apart from normal
hazards connected to the operation of the vessel (see EN 13445-3:2021, 5.3), the following hazards shall
be considered (as applicable):
— corrosion and chemical attack;
— wear;
— external fire;
— reasonably foreseeable misuse of the vessel.
6.2 Hazard removal and risk reduction
6.2.1 General
As far as practically feasible, the vessel shall be designed as to remove or reduce the respective risk. If
removal of a certain hazard is not feasible, the vessel shall be designed and equipped to protect against
the respective risk or (as a final measure) information be given on the hazard and what measures are to
be taken to reduce the risks from the hazard. Such information shall be given through warning signs and
in the operating instructions.
NOTE The procedure to follow is outlined in Figure 6.2–1.
6.2.2 Design considerations
If it is envisaged that safety accessories will have to be fitted to the vessel, the vessel shall be equipped
with the necessary connections for such accessories.
NOTE The selection, application and installation of safety related accessories intended to protect pressure
vessels during operation are covered in EN 764-7:2002.
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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)

Figure 6.2-1 — Hazard consideration
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SIST EN 13445-1:2021
EN 13445-1:2021 (E)
Issue 1 (2021-05)

(informative)

Using the standard
A.1 Purpose
This annex is designed to facilitate the introduction to the use of the standard.
This annex only gives a general overview of the requirements of the standard. Reference shall always be
made to the standard text itself, and not all requirements are necessarily mentioned in this annex.
A.2 General
The standard is harmonized under the Pressure Equipment Directive (2014/68/EU). This means that if
an unfired pressure vessel meets the requirements of the standard, this pressure vessel can be presumed
to conform to those essential safety requirements in Annex I of the Directive which are listed in the
Annexes ZA of the individual parts of the standard.
NOTE 1 A compilation of all annexes ZA can be found as Annex X of this Part 1.
In this connection, it should be understood that the standard is indivisible. The design and manufacture
of unfired pressure vessels requires the application of all relevant Parts of the standard for the
requirements of the standard to be fulfilled.
NOTE 2 Part 7 and Part 9 are not mandatory parts of the standard in this sense.
This standard applies to unfired pressure vessels with the limitations and exclusions stated in Clause 1
of this Part 1.
A.3 Prerequisites
Prior to designing and manufacturing a pressure vessel under the standard, the manufacturer shall
establish a number of prerequisites:
— The conditions under which the vessel will be operating.
— Load cases to be considered are enumerated in EN 13445-3:2021, 5.3.1 to 5.3.2 and also in clause 6
of this Part 1.
— The category of the vessel (I to IV) as defined in the Directive. CR 13445-7:2002, 4.2 and CR 13445-
7:2002, Annex A show how the category of a vessel is to be established.
NOTE 1 The category determines the type of inspection document required for the materials of the main
pressure-bearing parts, as stated in Annex I, section 4.3 of the Directive (Inspection Documents are defined in
EN 10204:2004). The category may also influence performance of welding, NDT qualification and particular
material appraisals (see A.4.2).
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— The assessment module (as defined in the directive) to be used. CR 13445-7:2002, 4.3 and CR 13445-
7:2002, Annex B describe the different assessment modules and which assessment modules can be
used for the different categories.
The choice of module may affect the participation of a notified body and/or a recognized third party
organization or user inspectorate in the inspection and testing of the vessel as enumerated in
CR 13445-7:2002, Annex C. (It should be noted that the use of user inspectorates may not be
permitted in all member states).
— The testing group of the vessel according to EN 13445-5:2021, 6.6.1.2. The available testing groups
depend upon the material group, thickness, and welding method. Testing Group 4 is further limited
with regards to pressure, temperature, content, number of cycles, and dimensions.
Although the same testing group normally applies to the whole vessel, it is (with the exception of
Group 4) permissible to have different testing groups apply to different parts (e.g., welds).
NOTE 2 The testing group affects not only the testing requirements but also design and manufacturing aspects,
e.g., joint coefficient, permitted weld details and required weld production tests.
A.4 Materials
A.4.1 General
Specific requirements for steels are given in Part 2.
Specific rules for spheroidal graphite cast iron, aluminium, and nickel/nickel alloys are given in
EN 13445-6:2021 (see A.8 in this annex), EN 13445-8:2021 (see A.9 in this annex), and
EN 13445-10:2021 (see A.10 in this annex), respectively. In some instances, references may be made
from these parts to EN 13445-2:2021.
A.4.2 Permitted materials
Only materials which are qualified for pressure equipment may be used. Qualification of materials can be
made in three different ways
— Materials from European harmonized standards, see EN 13445-2:2021, 4.3.1.
Certain materials supplied in accordance with European material Standards are accepted as qualified
for use in pressure-bearing parts. These materials are enumerated in EN 13445-2:2021, Table E.2-1.
— Materials with a European Approval for Materials (EAM), see EN 13445-2:2021, 4.3.2;
Materials with an EAM, which states that they can be used for products under the PED, are qualified
for use in relevant products according to this standard.
...