EN 1591-1:2001+A1:2009
(Main)Flanges and their joints - Design rules for gasketed circular flange connections - Part 1: Calculation method
Flanges and their joints - Design rules for gasketed circular flange connections - Part 1: Calculation method
1.1 General
This European Standard defines a Calculation method for bolted, gasketed, circular flange joints. Its purpose is to ensure structural integrity and control of leaktightness. The following equations use gasket parameters based on definitions and test methods specified in EN 13555.
1.2 Requirement for use of the Calculation method
Where permitted, the Calculation method is an alternative to design validation by other means e.g.
- special testing;
- proven practice;
- use of standard flanges within permitted conditions.
1.3 Validity
1.3.1 Geometry
The Calculation method is applicable to the configurations having:
- flanges whose section is given or may be assimilated to those given in Figures 4 to 12;
- four or more identical bolts uniformly distributed;
- gasket whose section and configuration after loading can be assimilated by one of those given in Figure 3;
- flange dimension which meet the following conditions:
a) 0,2 ≤ bF/eF ≤ 5,0; 0,2 ≤ bL/eL ≤ 5,0
b) eF ≤ max {e2; dB0; pB x }
c)
NOTE For explanations of symbols see clause 3.
NOTE The condition bF/eF ≤ 5,0 need not be met for collar in combination with loose flange.
NOTE The condition is for limitation of non-uniformity of gasket pressure due
to spacing of bolts. The values 0,01 and 0,10 are to be applied for soft (non-metallic) and hard (metallic)
gaskets respectively. A more precise criterion is given in annex A.
NOTE Attention may need to be given to the effects of tolerances and corrosion on dimensions; reference should be made to other codes under which the calculation is made, for example values are given in EN 13445 and EN 13480.
The following configurations are outside the scope of the Calculation method:
- flanges of essentially non-axisymmetric geometry, e.g. split loose flanges, web reinforced flanges;
Flansche und Flanschverbindungen - Regeln für die Auslegung von Flanschverbindungen mit runden Flanschen und Dichtung - Teil 1: Berechnungsmethode
Brides et leurs assemblages - Règles de calcul des assemblages à brides circulaires avec joint - Partie 1: Méthode de calcul
1.1 Généralités
La présente Norme européenne définit une méthode de calcul des assemblages à brides boulonnées circulaires
avec joint. Son objectif est d'en assurer l'intégrité structurale et la maîtrise de l'étanchéité. !Les équations
suivantes utilisent des paramètres de joints basés sur les définitions et les modes opératoires d'essais spécifiés
dans l’EN 13555."
1.2 Prescription d'emploi
La méthode de calcul est destinée à être utilisée lorsqu’un code ou une réglementation l'exige. Elle constitue l’une
des alternatives possibles (quand cela est permis), pour la justification de la conception d'un assemblage, au même
titre que d’autres, par exemple :
— des essais spécifiques ;
— la référence à une expérience pratique justifiée ;
— l'utilisation de brides normalisées, dans les conditions autorisées.
1.3 Domaine de validité
1.3.1 Géométrie
La méthode de calcul est applicable aux configurations présentant :
— des brides dont la section correspond ou peut être assimilée à l’une de celles présentées dans les Figures 4 à 12 ;
— quatre boulons identiques ou plus, répartis régulièrement ;
— un joint dont la section et la configuration après chargement peuvent être assimilés à l’une de celles présentées
en Figure 3 ;
— des dimensions de brides qui satisfont aux conditions suivantes :
a) 0,2 ≤ bF / eF ≤ 5,0 ; 0,2 ≤ bL / eL ≤ 5,0 ;
b) eF ≤ max ;
c) cos ϕ ≥ 1/(1 + 0,01 ds / es).
NOTE 1 Voir article 3 pour la signification des symboles.
NOTE 2 La condition bF / eF ≤ 5,0 n'a pas besoin d'être satisfaite pour le collet d'une bride tournante.
NOTE 3 La condition eF ≥ pB × a pour objet de limiter l'inégalité de la répartition de la compression
du joint qui peut résulter de l'espacement des boulons. Les valeurs 0,01 et 0,10 sont à utiliser respectivement pour les joints
à faible dureté (non métalliques) et pour les joints durs (métalliques). Un critère plus précis est donné en annexe A.
Prirobnice in prirobnični spoji - Pravila za načrtovanje okroglih prirobničnih spojev s tesnili - 1. del: Način izračuna
Ta evropski standard opredeljuje način izračuna za vijačne in tesnilne okrogle prirobnice in prirobnične spoje. Njegov namen je zagotoviti strukturno celovitost in nadzor neprepustnosti.
General Information
Relations
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Flansche und ihre Verbindungen - Regeln für die Auslegung von Flanschverbindungen mit runden Flanschen und Dichtung - Teil 1: BerechnungsmethodeBrides et leurs assemblages - Règles de calcul des assemblages à brides circulaires avec joint - Partie 1: Méthode de calculFlanges and their joints - Design rules for gasketed circular flange connections - Part 1: Calculation method23.040.60Prirobnice, oglavki in spojni elementiFlanges, couplings and jointsICS:Ta slovenski standard je istoveten z:EN 1591-1:2001+A1:2009SIST EN 1591-1:2002+A1:2009en,fr01-maj-2009SIST EN 1591-1:2002+A1:2009SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 1591-1:2001+A1
March 2009 ICS 23.040.60 Supersedes EN 1591-1:2001English Version
Flanges and their joints - Design rules for gasketed circular flange connections - Part 1: Calculation method
Brides et leurs assemblages - Règles de calcul des assemblages à brides circulaires avec joint - Partie 1: Méthode de calcul
Flansche und ihre Verbindungen - Regeln für die Auslegung von Flanschverbindungen mit runden Flanschen und Dichtung - Teil 1: Berechnungsmethode This European Standard was approved by CEN on 8 March 2001 and includes Amendment 1 approved by CEN on 7 February 2009.
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 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 Management Centre has the same status as the official 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 STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre:
Avenue Marnix 17,
B-1000 Brussels © 2009 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1591-1:2001+A1:2009: ESIST EN 1591-1:2002+A1:2009
Requirement for limitation of non-uniformity of gasket stress . 41Annex B (informative)
Dimensions of standard metric bolts . 42Annex C (informative)
Scatter of bolting-up methods . 43Annex D (informative)
Assembly using torque wrench . 44Annex E (informative)
Flange rotations . 46E.1General . 46E.2Use of flange rotation . 46E.3Calculation of flange rotations . 46Annex F (informative)
Diagram of calculation sequence . 48Annex G (informative)
Joints with spacer-seated flanges . 50G.1Introduction . 50G.2Behaviour of spacer-seated gaskets . 50G.3Simplified treatment . 50Annex H (normative)
!!!!Use of the former creep factor gC"""" . 55Annex ZA (informative)
!Relationship between this European Standard and the Essential Requirements of EU Directive 97/23/EC"""" . 56Bibliography . 57SIST EN 1591-1:2002+A1:2009
Foreword This document (EN 1591-1:2001+A1:2009) has been prepared by Technical Committee CEN/TC 74 "Flanges and their joints", the secretariat of which is held by DIN.
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 September 2009, and conflicting national standards shall be withdrawn at the latest by September 2009.
This document includes Amendment 1, approved by CEN on 2009-02-07. This document supersedes EN 1591-1:2001. The start and finish of text introduced or altered by amendment is indicated in the text by tags ! ".
This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. This European Standard is considered as a supporting standard to other application and product standards which in themselves support an essential safety requirement of a New Approach Directive and will appear as a normative reference in them.
For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this standard.
EN 1591 consists of two parts:
– EN 1591-1 Flanges and their joints – Design rules for gasketed circular flange connections – Part 1: Calculation method
– !EN 1591-2" Flanges and their joints – Design rules for gasketed circular flange connections – Part 2: Gasket parameters
The Calculation method satisfies both leaktightness and strength criteria. The behaviour of the complete flanges-bolts-gasket system is considered. Parameters taken into account include not only basic ones such as:
– fluid pressure;
– material strength values of flanges, bolts and gaskets;
– gasket compression factors;
– nominal bolt load;
but also:
– possible scatter due to bolting up procedure;
– changes in gasket force due to deformation of all components of the joint;
– influence of connected shell or pipe;
– effect of external axial forces and bending moments; SIST EN 1591-1:2002+A1:2009
– effect of temperature difference between bolts and flange ring
Calculation for sealing performance is based on elastic analysis of the load/deformation relations between all parts of the flange connection, corrected by a possible plastic behaviour of the gasket material. Calculation for mechanical resistance is based on (plastic) limit analysis of the flange-shell combination. Both internal and external loads are considered. Load conditions covered include initial assembly, hydrostatic test, and all significant subsequent operating conditions. The calculation steps are broadly as follows:
1) First, the required minimum initial bolt load (to be reached at bolting-up) is determined, so that in any subsequent specified load condition, the residual force on the gasket will never be less than the minimum mean value required for the gasket (value is gasket data from !EN 1591-2", for instance). The determination of this load is iterative, because it depends on the effective gasket width, which itself depends on the initial bolt load.
2) Then, the internal forces that result from the selected value of initial bolt load are derived for all load conditions, and the admissibility of combined external and internal forces is checked as follows:
bolting-up condition: the check is performed against the maximum possible bolt force that may result from the bolting-up procedure; test and operating conditions: checks are performed against the minimum necessary forces, to ensure that the connection will be able to develop these minimum forces without risk of yielding, except in highly localized areas. Higher actual initial bolting results in (limited) plastic deformation in subsequent conditions (test, operation). But the checks so defined assure that these deformations will not reduce the bolt force to a value less than the minimum required.
If necessary, the flange rotations may be estimated in all load conditions, using annex E, and the values obtained, compared with the relevant gasket limits which could apply.
Checks for admissibility of loads imply safety factors which are those applied to material yield stress or strength in the determination of the nominal design stresses used in the Calculation method.
NOTE Where flanges are used to comply with other codes the Calculation method does not specify values for nominal stresses.
Nevertheless, since all significant design parameters are accounted for, the use of low safety factors is made possible by special use of nominal design stresses:
for assembly conditions the nominal design stresses have the same values as for the hydraulic pressure tests (normally higher than for operating conditions); – the nominal design stresses for the bolts are determined by the same rules as relevant for the flange and shell material e.g. same safety factor on yield stress.
The minimum force required on the gasket for leak tightness considerations may be established by two different ways:
1) Use of tabulated gasket factors, for example those given in !EN 1591-2", which are based on industrial experience and correspond to mainly gas and steam leak rates.
2) Derivation from measured leak rate versus gasket stress data, if available for the gasket, for example as in !EN 1591-2". This permits design to be based on any specified maximum leak rate.
The use of this Calculation method is particularly useful for joints where the bolt load is monitored when bolting up. The greater the precision of this, the more benefit can be gained from application of the Calculation method.
In the present stage of development, the Calculation method is
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.