SIST EN 13445-1:2009

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Unbefeuerte Druckbehälter - Teil 1: AllgemeinesRécipients sous pression non soumis à la flamme - Partie 1 : généralitésUnfired pressure vessels - Part 1: General23.020.30MHNOHQNHPressure vessels, gas cylindersICS:Ta slovenski standard je istoveten z:EN 13445-1:2009SIST EN 13445-1:2009en,fr,de01-november-2009SIST EN 13445-1:2009SLOVENSKI
STANDARDSIST EN 13445-1:2002/A3:2007SIST EN 13445-1:2002/A2:2007SIST EN 13445-1:2002/A1:20091DGRPHãþD



SIST EN 13445-1:2009



EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 13445-1July 2009ICS 23.020.30Supersedes EN 13445-1:2002
English VersionUnfired pressure vessels - Part 1: GeneralRécipients sous pression non soumis à la flamme - Partie 1: généralitésUnbefeuerte Druckbehälter - Teil 1: AllgemeinesThis European Standard was approved by CEN on 30 June 2009.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN 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 translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre:
Avenue Marnix 17,
B-1000 Brussels© 2009 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 13445-1:2009: ESIST EN 13445-1:2009



EN 13445-1:2009 (E) Issue 1 (2009-07) 2 Contents Page Foreword.3 Introduction.5 1 Scope.7 2 Normative references.7 3 Terms and definitions.8 4 Interdependency of the parts of the series.9 5 Quantities, symbols and units.9 Annex A (informative)
Using the standard.12 Annex B (informative)
Index.23 Annex Y (informative)
Differences between EN 13445:2002 and EN 13445:2009.37 Annex ZA
(informative)
Relationship between this European Standard and the Essential Requirements of the EU Pressure Equipment Directive 97/23/EC.38 Bibliography.39
SIST EN 13445-1:2009



EN 13445-1:2009 (E)
Issue 1 (2009-07) 3 Foreword This document (EN 13445-1:2009) 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 December 2009, and conflicting national standards shall be withdrawn at the latest by December 2009. 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 document has been prepared under a mandate 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. This European Standard concerning “Unfired pressure vessels” comprises the following Parts: ⎯ Part 1: General. ⎯ Part 2: Materials. ⎯ Part 3: Design. ⎯ Part 4: Fabrication. ⎯ Part 5: Inspection and testing. ⎯ Part 6: Requirements for the design and fabrication of pressure vessels and pressure parts constructed from spheroidal graphite cast iron. ⎯ CR 13445-7, Unfired pressure vessels — Part 7: Guidance on the use of conformity assessment procedures.
⎯ Part 8: Additional requirements for pressure vessels of aluminium and aluminium alloys. ⎯ CEN/TR 13445-9, Unfired pressure vessels — Part 9: Conformance of EN 13445 series to ISO 16528. 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). The link and information related to the Help Desk can be found at http://www.cen.eu/cenorm/sectors/sectors/mechanicalengineering/pressure/index.asp. 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. SIST EN 13445-1:2009



EN 13445-1:2009 (E) Issue 1 (2009-07) 4 This document supersedes EN 13445-1:2002. This new edition incorporates the Amendments which have been approved previously by CEN members, and the corrected pages up to Issue 36 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 13445:2009 each year, 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, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
SIST EN 13445-1:2009



EN 13445-1:2009 (E)
Issue 1 (2009-07) 5 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 and 8 specifically deal with vessels of spheroidal graphite cast iron and aluminium, 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. NOTE It is intended to revise EN 764-2:2002 for consistence, with EN 13445. 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 harmoniz flange design across European standards. Part 4 This part is based on existing good practice in previous national European Standards on manufacturing. It covers forming, welding procedures and welding qualification, production testing, and post weld heat treatment and repairs. Rules are also provided for material traceability and tolerances. 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. SIST EN 13445-1:2009



EN 13445-1:2009 (E) Issue 1 (2009-07) 6 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 5817:2003 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. It is not a standard, but merely 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. SIST EN 13445-1:2009



EN 13445-1:2009 (E)
Issue 1 (2009-07) 7 1 Scope 1.1
This part of this European Standard defines the terms, definitions, quantities, symbols and units that are used throughout the EN 13445. 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 the user of the EN 13445.
This European Standard 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. NOTE The selection, application and installation of safety related accessories intended to protect pressure vessels during operation are covered in EN 764-7. 1.2 Exclusions This European Standard is not applicable to pressure equipment of the following types: a) transportable pressure equipment; b) items specifically designed for nuclear use, the failure of which may cause a release of radioactivity; c) pressure equipment intended for the generation of steam or superheated water at temperatures higher than 110 °C; d) vessels of riveted construction; e) vessels of lamellar cast iron or any other materials not included in parts 2, 6, or 8 of the standard; f) multilayered, autofrettaged or pre-stressed vessels; g) pipelines and industrial piping. 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)
EN 764-1:2004, Pressure Equipment — Part 1: Terminology — Pressure, temperature, volume, nominal size. EN 764-2:2002, Pressure Equipment — Part 2: Quantities, symbols and units. EN 764-3:2002, Pressure Equipment — Part 3: Definition of parties involved. EN 13445-2:2009, Unfired pressure vessels — Part 2: Materials. EN 13445-3:2009, Unfired pressure vessels — Part 3: Design. EN 13445-4:2009, Unfired pressure vessels — Part 4: Fabrication. SIST EN 13445-1:2009



EN 13445-1:2009 (E) Issue 1 (2009-07) 8 EN 13445-5:2009, Unfired pressure vessels — Part 5: Inspection and testing. EN 13445-6:2009, Unfired pressure vessels — Part 6: Requirements for the design and fabrication of pressure vessels and pressure parts constructed from spheroidal graphite cast iron. EN 13445-8:2009, Unfired pressure vessels — Part 8: Additional requirements for pressure vessels of aluminium and aluminium alloys. 3 Terms and definitions For the purposes of this European Standard, the terms and definitions given in EN 764-1:2004, EN 764-2:2002 and EN 764-3:2002 and the following apply. 3.1 main pressure bearing parts parts which constitute the envelope under pressure, essential for the integrity of the equipment 3.2 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 A vessel may be composed of more than one chamber. 3.3 fluid gas, liquid and vapour in their pure phase as well as mixtures thereof
NOTE A fluid may contain a suspension of solids. 3.4 piping pipe or system of pipes, tubing, fittings, expansion joints, hoses or other pressure-bearing components, intended for the transport of fluid, connected together and integrated into a pressure system 3.5 assembly several pieces of pressure equipment assembled by a manufacturer to constitute an integrated and functional whole 3.6 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 3.7 maximum allowable pressure (PS) maximum pressure for which the pressure vessel is designed as specified by the manufacturer
3.8 maximum/minimum allowable temperature (TS) maximum/minimum temperature for which the pressure vessel is designed as specified by the manufacturer 3.9 testing group one of the four groups designed to specify the extent of non-destructive testing and destructive testing necessary in association with joint coefficient, material grouping, welding process, maximum thickness, service temperature range SIST EN 13445-1:2009



EN 13445-1:2009 (E)
Issue 1 (2009-07) 9 NOTE The testing group of a vessel is not linked to the hazard category. 3.10 joint coefficient reduction coefficient related to the testing group and which is applied to the nominal design stress 3.11 required thickness thickness excluding corrosion or any other allowances specified in EN 13445 3.12 hazard category category of the pressure vessel taking into account the potential hazards 3.13 testing factor a factor taking into account the amount of NDT testing in castings, applied on the nominal design stress 3.14 material manufacturer individual or organization that produces material in the basic product form used in the manufacture of pressure equipment 3.15 manufacturer individual or organization that is responsible for design, fabrication, testing, inspection, installation of pressure equipment and assemblies where relevant NOTE 1 The manufacturer may subcontract one or more of the above mentioned tasks under its responsibility. NOTE 2 In EU member states the manufacturer is responsible for compliance with the Pressure Equipment Directive 97/23/EC. For those manufacturers outside the EU their authorized representative inside the EU assumes this responsibility.
3.16 weldment weld metal, heat affected zone and adjacent base material(s) 4 Interdependency of the parts of the series Parts 2 to 6 and part 8 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 764-2:2002
NOTE 1 Other symbols used in specific parts of this European Standard are tabulated in the relevant part. SIST EN 13445-1:2009



EN 13445-1:2009 (E) Issue 1 (2009-07) 10 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. Table 5-1 — Quantities for space and time Quantity Symbol Unit Time t s, min, h Frequency f Hz Dimension any Latin letter a mm Length l mm Thickness e mm Corrosion allowance c mm Diameter d, D mm Radius r, R mm Area A, S mm2 Volume, capacity V mm3 b c Weight W N, kN Density ρ kg/mm3 d Second moment of area Ι mm4 Section modulus Z mm3 Acceleration γ m/s2 Plane angle any Greek letter a rad, ° a Symbols may use any lower-case letter, except for those defined elsewhere in this table. b volume may also be given in m3 or L. c litre "L" is a non-SI unit which may be used with SI units and their multiples. d Density may also be given in kg/m3. SIST EN 13445-1:2009



EN 13445-1:2009 (E)
Issue 1 (2009-07) 11 Table 5-2 — Mechanical quantities
Quantity a Symbol b Unit Force F N Moment M N.mm Pressure p, P
bar c, MPa Temperature T °C Linear expansion coefficient α μm/m°C Normal stress σ MPa Shear stress τ MPa Nominal design stress f MPa Tensile strength
Rm MPa Yield strength Re MPa 1 % proof strength Rp1.0 MPa Proof strength at temperature T Rp/T MPa Upper yield strength
ReH MPa 0,2 % proof strength
Rp0,2 MPa 0,2 % proof strength at temperature T Rp0,2/T MPa Ultimate tensile strength at temperature T Rm/T MPa 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 97/23/EC. Note
The use of symbols for temperature may be different from the PED. SIST EN 13445-1:2009



EN 13445-1:2009 (E) Issue 1 (2009-07) 12 Annex A (informative)
Using the standard A.1 Purpose EN 13445 is a new standard (first issued in 2002) and in many places uses new design, fabrication, inspection, and testing philosophies. 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 must 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 (97/23/EC). 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. 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. Only in the case that the standard gives no information to specific parts of pressure vessels other standards may be used exceptionally. In such a case, special attention should be paid to ensure that application of such other standard(s) is made consistent with the safety philosophy and the general safety requirements of EN 13445 (i.e. same nominal design stresses, same safety margins, etc.). NOTE 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 EN 13445-1:2009. A.3 Prerequisites Prior to designing and manufacturing a pressure vessel under the standard, the manufacturer must establish a number of prerequisites: ⎯ The conditions under which the vessel will be operating. ⎯ Load cases to be considered are enumerated in 5.3.1 to 5.3.2 of EN 13445-3:2009. ⎯ The category of the vessel (I to IV) as defined in the Directive. Subclause 4.2 of CR 13445-7:2002 and Annex A of CR 13445-7:2002 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 how particular material appraisals (see A.4.2) are to be performed. ⎯ The assessment module (as defined in the directive) to be used. Subclause 4.3 of CR 13445-7:2002 and Annex B of CR 13445-7:2002 describe the different assessment modules and which assessment modules can be used for the different categories. SIST EN 13445-1:2009



EN 13445-1:2009 (E)
Issue 1 (2009-07) 13 NOTE 2 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 Annex C of CR 13445-7:2002. (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 6.6.1.1 of EN 13445-5:2009. The available testing groups depend upon the material group, thickness, and welding method. Category 4 is further limited with regards to pressure, temperature, content, number of cycles, design stress, and dimensions.
NOTE 3 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.
NOTE 4 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). A.4 Materials A.4.1 General Specific requirements for steels are given in Part 2.
NOTE Specific rules for spheroidal graphite cast iron and aluminium are given in EN13445-6:2009 (see A.8 in this annex) and EN13445-8:2009 (see A.9 in this annex), respectively. In some instances, references may be made from these parts to EN13445-2:2009. 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 4.3.1 of EN 13445-2:2009; Certain materials supplied in accordance with European material Standards are accepted as qualified for use in pressure-bearing parts. These materials are enumerated in Table E.2-1 of EN 13445-2:2009. ⎯ Materials with a European Approval for Materials (EAM), see 4.3.2 of EN 13445-2:2009; 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. EAMs are published in the Official Journal, and the European Commission maintains a list of EAMs on their web site NOTE 1 This web site is presently accessible under the address http://ec.europa.eu/enterprise/pressure_equipment/ped/materials/published_en.html.
⎯ Materials with a Particular Material Appraisal (PMA) , see 4.3.3 of EN 13445-2:2009. Materials, which have been subject to a PMA are qualified. This appraisal is carried out by the manufacturer (and in certain cases checked by a Notified Body).
NOTE 2 The European Commission and Member States have in November 2006 agreed on ”Guiding Principles for the contents of Particular Materials Appraisals. The document is published on, http://ec.europa.eu/enterprise/pressure_equipment/ped/materials/index_en.html. SIST EN 13445-1:2009



EN 13445-1:2009 (E) Issue 1 (2009-07) 14 Whichever method of qualification is used, the qualification does not necessarily cover the suitability of the material with regards to the environment and content of the vessel, i.e., corrosion, erosion, etc. The manufacturer will always have to evaluate the material's resistance to such action.
Whichever way the material has been qualified, all other rules in Part 2 will have to be fulfilled. A.4.3 Prevention of brittle fracture Rules for prevention against brittle fracture are given in Annex B of EN 13445-2:2009. Three different routes are allowed: ⎯ Code of practice based on operating experience and fracture mechanics (B.2.2 of EN 13445-2:2009). ⎯ Code of more flexibility based on fracture mechanics (B.2.3 of EN 13445-2:2009). ⎯ Application of fracture mechanics analysis (B.2.4 of EN 13445-2:2009). The first two methods are limited to certain materials and thickness. The third method requires detailed work in fracture mechanics and the standard only contains guidance on it. It can only be used after agreement between the concerned parties.
A.4.4 Material grouping Materials are grouped in Table A-1 of EN 13445-2:2009 with respect to major chemical elements, specified minimum tensile test data. This grouping is used throughout the standard to decide design, manufacturing, and inspection aspects. A.5 Design A.5.1 General Most of the requirements for design are to be found in Part 3. NOTE Specific design rules for vessels manufactured from spheroidal graphite cast iron and aluminium are given in EN13445-6:2009 (see A.8 in this annex) and EN13445-8:2009 (see A.9 in this annex), respectively. A.5.2 Design for static loads There are four different methods for design, which can be used either separately or in combination with each other ⎯ Design by formulas (DBF) These rules are contained in Clauses 7 to 16 and 20 to 21 of EN 13445-3:2009 and Annexes F, G, GA and J of EN 13445-3:2009. For simple geometries such as cylinders and spheres, formulas can be given where pressure and geometrical dimensions give the required minimum thicknesses directly. For more complicated geometries, a trial-and-error approach must be used in most cases. The designer will have to assume the analysis thickness(es), and use the formulas to compute the stresses and/or the load ratios as applicable. These stresses and/or load ratios are then compared with allowable values. Figure 5-1 of EN 13445-3:2009 shows the relations between different thickness definitions.
SIST EN 13445-1:2009



EN 13445-1:2009 (E)
Issue 1 (2009-07) 15 In the design formulas of components having a governing weld, the weakening effect of that weld is accounted for by means of a joint coefficient z. The maximum allowed value of this coefficient depends upon the testing group of the weld as specified in 6.6.1.1 of EN 13445-5:2009.
NOTE 1 Governing welds are listed in 5.6 of EN 13445-3:2009. For two types of components, flange connections and heat exchanger tubesheets, a multiple sets of rules are given (in Clause 11 of EN 13445-3:2009, Annex G of EN 13445-3:2009, and Annex GA of EN 13445-3:2009, in Clause
...