CEN/TS 764-8:2016
(Main)Pressure equipment and assemblies - Part 8: Proof test
Pressure equipment and assemblies - Part 8: Proof test
This document specifies the purpose, form and procedure of proof testing by pressure test of items of pressure equipment and assemblies.
It also specifies how to determine the value of the test pressure.
Druckgeräte und Zusammenbauten- Teil 8: Druckprüfung
Dieses Dokument legt den Zweck, die Form und die Durchführung der Druckprüfung anhand von Druck-versuchen an Druckgeräteteilen und Baugruppen fest.
Es legt ebenfalls das Verfahren für die Bestimmung des Druckwertes für den Druckversuch fest.
Équipements sous pression et ensembles - Partie 8: Épreuve
Le présent document précise le but, la forme et la procédure de l'épreuve par essai de pression des équipements et ensembles sous pression.
Il spécifie également comment déterminer la valeur de l'essai de pression.
Tlačna oprema in sklopi - 8. del: Preskušanje
Ta dokument določa namen, obliko in postopek preskušanja s tlačnim preskusom delov tlačne opreme in sklopov. Opredeljuje tudi način za določitev vrednosti preskusnega tlaka.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-oktober-2016
7ODþQDRSUHPDLQVNORSLGHO 3UHVNXãDQMH
Pressure equipment and assemblies - Part 8: Proof test
Druckgeräte und Zusammenbauten- Teil 8: Druckprüfung
Équipements sous pression et ensembles - Partie 8 : Épreuve
Ta slovenski standard je istoveten z: CEN/TS 764-8:2016
ICS:
23.020.32 7ODþQHSRVRGH Pressure vessels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
CEN/TS 764-8
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
June 2016
TECHNISCHE SPEZIFIKATION
ICS 23.020.30
English Version
Pressure equipment and assemblies - Part 8: Proof test
Équipements sous pression et ensembles - Partie 8: Druckgeräte und Zusammenbauten- Teil 8:
Épreuve Druckprüfung
This Technical Specification (CEN/TS) was approved by CEN on 8 March 2016 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of 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, 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: Avenue Marnix 17, B-1000 Brussels
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 764-8:2016 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Terms and definitions . 5
3 Symbols and abbreviations . 6
4 General . 6
4.1 Purpose of proof testing by pressure test . 6
4.2 Form of the pressure test . 6
4.3 Pressure test procedure . 7
5 Pressure equipment . 7
5.1 Hydrostatic test . 7
5.1.1 Basic rule . 7
5.1.2 Specific adjustment . 8
5.1.3 Creep consideration . 8
5.2 Pneumatic test . 8
6 Assemblies . 9
Annex A (informative) Guidelines from the European Commission . 10
Bibliography . 12
European foreword
This document (CEN/TS 764-8:2016) has been prepared by Technical Committee CEN/TC 54 “Unfired
pressure vessels”, the secretariat of which is held by BSI.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This European Standard consists of eight parts, which are currently:
Part 1 Vocabulary;
Part 2 Quantities, symbols and units;
Part 4 Establishment of technical delivery conditions for metallic materials;
Part 5 Inspection documentation of metallic materials and compliance with the material specification;
Part 6 Structure and content of operating instructions [technical report];
Part 7 Safety systems for unfired pressure equipment;
Part 8 Proof test [technical specification].
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to announce this Technical Specification: 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, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Introduction
This document is intended to establish a common approach for the proof testing by pressure test of
items of pressure equipment and assemblies, in order to fulfil the essential requirement 3.2.2 of
Annex 1 of the pressure equipment directive 97/23/CE.
It is intended to be used as a basis in the specific product standards, or directly by a manufacturer.
It takes into account the existing guidelines adopted by the European Commission, detailed in Annex A.
For the determination of the pressure test value, this document provides two methods in 5.1. Further
investigation will take place, in order to better specify the method to be retained in the future. The
determination of the nominal design stress will be part of this analysis.
CEN technical committees, which apply this document in their product standard, are encouraged to give
feedback to CEN/TC 54, for the future revision of this document.
1 Scope
This document specifies the purpose, form and procedure of proof testing by pressure test of items of
pressure equipment and assemblies.
It also specifies how to determine the value of the test pressure.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
NOTE Other useful definitions can be found in EN 764–1 to -7.
2.1
pressure equipment
vessel, piping, safety accessory or pressure accessory with a maximum allowable pressure PS greater
than 0,5 bar
Note 1 to entry: Where applicable, pressure equipment includes elements attached to pressurized parts, such as
flanges, nozzles, couplings, supports, lifting lugs, etc.
[SOURCE: Directive 97/23/CE]
2.2
assembly
several pieces of pressure equipment assembled by a manufacturer to constitute an integrated and
functional whole
[SOURCE: Directive 97/23/CE]
2.3
product standard
standard that specifies requirements to be fulfilled by a product or a group of products, to establish its
fitness for purpose
Note 1 to entry: For this document, a product standard is a standard dealing with a pressure equipment or an
assembly.
[SOURCE: EN 45020]
2.4
maximum allowable pressure
PS
p
s
maximum pressure for which the equipment is designed, as specified by the manufacturer
Note 1 to entry: The subscript “max” is added to the symbol for maximum values.
[SOURCE: EN 764-1]
2.5
test pressure
PT
p
t
pressure to which the equipment is subjected for test purposes
[SOURCE: EN 764-1]
3 Symbols and abbreviations
For the purposes of this document, the symbols and abbreviations shall be in accordance with Table 1.
Table 1 — Symbols, descriptions and units
Symbol Description Unit
a maximum allowable pressure b
PS, p MPa
s
a test pressure b
PT, p MPa
t
c material strength characteristic MPa
k
a
p or p for calculation purposes ; PS or PT for marking purposes
s t
b
MPa for calculation purpose, otherwise the unit may be bar (1 MPa = 10 bar)
c
subscript 20 or T is used for ambient temperature or maximum allowable temperature, respectively
4 General
4.1 Purpose of proof testing by pressure test
Proof testing by pressure test shall be a test for the pressure containment aspect, which verifies the
adequacy of manufacture. In addition, it can demonstrate tightness of the equipment.
NOTE 1 The proof testing by pressure test is not primarily intended to prove the design or to change material
behaviour or dimensioning of the equipment.
NOTE 2 Leak tightness, in the frame of this document, only considers testing under positive hydraulic or
pneumatic pressure and aims at ensuring a visually leak tight assembly without a precise quantification. If
necessary, additional tightness test are conducted as per the requirements of the product standard.
4.2 Form of the pressure test
For pressure equipment, the hydrostatic pressure test, as described in 5.1, shall be the standard
pressure test. If this is not practical then it may be substituted by:
a) a pneumatic test as described in 5.2;
b) a combined hydrostatic/pneumatic test.
The manufacturer shall document the form of the pressure test in the documentation, which shall be
reviewed before manufacturing commencing.
For assemblies, refer to Clause 6.
NOTE Local regulations may apply to the performance of pneumatic testing.
4.3 Pressure test procedure
Any item of pressure equipment shall be subjected to a pressure test; however items of category I may
be tested on a statistical basis.
The test sequence shall consist of the following:
— filling the equipment and pressurising it gradually;
— maintaining the required test pressure for a sufficient length of time;
— reducing the pressure for inspection where necessary;
— visually inspecting it to check if there has been any deterioration, deformation and/or leak
resulting from the pressure test;
— deciding if any possible deterioration, deformation and/or leak is acceptable;
— then, fully draining and cleaning the equipment.
Items that have a value of p less than that determined in accordance with the requirements of Clause 5,
t
and that are not part of the pressure-bearing housing of the equipment, shall be removed or isolated
during the pressure test.
For assemblies, refer to Clause 6.
5 Pressure equipment
5.1 Hydrostatic test
5.1.1 Basic rule
The test pressure shall be based on p and k, with possible specific adjustment as stated in 5.1.2.
s
NOTE 1 Design takes account of maximum loadings and variation in allowable stresses across the design
temperature range. This leads to selection of material grades, thicknesses and permanent joining processes. To
test the adequacy of manufacture, the value of k is considered a practical parameter, which is applicable to
determining the temperature related effects.
The test pressure shall be determined by the greater of the following values for p :
t
k
p = a⋅ p
t s
k
T
or
p = b⋅ p
t s
where
a and b are coefficients depending on the type of pressure equipment, defined as follows:
— for vessels, a = 1,25 and b = 1,43;
— for piping, pressure accessories, safety accessories, or items of pressure equipment constituting
boilers, a and b are defined in the product standard, generally the same values as for vessels.
NOTE 2 Boilers as such are considered as assemblies, covered under Clause 6.
k is defined in accordance with one of the following two methods:
— k is the nominal design stress of the considered material whenever this value is determined for the
design;
— k is a material property defined in the technical specification for the material below the creep
range, to be used for the item of pressure equipment. k is either the yield strength or rupture
strength as appropriate, to be decided in the product standard.
NOTE 3 The above equations intentionally do not relate to the remaining thickness after corrosion has taken
place.
For items of pressure equipment that consists of several pressure parts (with several ratios), the
smallest of the ratios in the above formula shall be used. Further details can be specified in the product
standard.
5.1.2 Specific adjustment
In specific cases, it may be necessary to adjust the basic rule to take account of more complex situations
(e.g. PS and TS not coincidental, compensation for water column etc.). The purpose of the adjusted
max max
rule shall still comply with 4.1 without resul
...
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