EN 1759-4:2003

SLOVENSKI STANDARD
01-junij-2004
Prirobnice in prirobnični spoji - Okrogle prirobnice za cevi, ventile, fitinge in pribor
z oznako Class - 4. del: Prirobnice iz aluminijevih zlitin
Flanges and their joint - Circular flanges for pipes, valves, fittings and accessories, class
designated - Part 4: Aluminium alloy flanges
Flansche und ihre Verbindungen - Runde Flansche für Rohre, Armaturen, Formstücke
und Zubehörteile, nach Class bezeichnet - Teil 4: Flansche aus Aluminiumlegierungen
Brides et leurs assemblages - Brides circulaires pour tubes, appareils de robinetterie,
raccords et accessoires, désignées Class - Partie 4: Brides en alliages d'aluminium
Ta slovenski standard je istoveten z: EN 1759-4:2003
ICS:
23.040.60 Prirobnice, oglavki in spojni Flanges, couplings and joints
elementi
77.150.10 Aluminijski izdelki Aluminium products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 1759-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2003
ICS 23.040.60
English version
Flanges and their joint - Circular flanges for pipes, valves,
fittings and accessories, class designated - Part 4: Aluminium
alloy flanges
Brides et leurs assemblages - Brides circulaires pour tubes, Flansche und ihre Verbindungen - Runde Flansche für
appareils de robinetterie, raccords et accessoires, Rohre, Armaturen, Formstücke und Zubehörteile, nach
désignées Class - Partie 4: Brides en alliages d'aluminium Class bezeichnet - Teil 4: Flansche aus
Aluminiumlegierungen
This European Standard was approved by CEN on 10 July 2003.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2003 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1759-4:2003 E
worldwide for CEN national Members.

Contents Page
Foreword.3
1 Scope .4
2 Normative references .4
3 Terms and definitions.4
4 Designations.5
4.1 Range of nominal sizes .5
4.2 Range of Class designations.5
4.3 Types of flanges.5
4.4 Designation of flanges .5
5 General requirements.6
5.1 Flange materials.6
5.2 Repairs.6
5.3 Bolting.6
5.4 Gaskets .6
5.5 Pressure/temperature (p/T) ratings.6
5.6 Dimensions.6
5.7 Flange facings.7
5.7.1 Types of jointing faces .7
5.7.2 Jointing face finish .7
5.8 Spot facing and back facing of flanges .7
5.9 Tolerances .7
5.10 Marking .7
Annex A (informative) Masses of flanges .14
Annex B (informative) Comparison of metric bolting to imperial bolting.15
Annex ZA (informative) Relationship between this European Standard and the Essential Requirements
of EU Directive 97/23/EC .16
Foreword
This document (EN 1759-4:2003) has been prepared by Technical Committee CEN/TC74 "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 March 2004, and conflicting national standards shall be withdrawn at the latest by
March 2004.
This document has been prepared under a mandate given to CEN by the European Commission and the European
1)
Free Trade Association, and supports essential requirements of the Pressure Equipment Directive (PED) .
For relationship with EU Directive(s), see informative annex ZA, which is an integral part of this standard.
EN 1759 consists of the following parts:
� Part 1: Steel flanges (draft stage);
� Part 3: Copper alloy flanges (draft stage);
� Part 4: Aluminium alloy flanges
The mating dimensions of the flanges of this standard are compatible with those flanges of other materials in ac-
cordance with the other parts of EN 1759 and with those flanges of ISO 7005.
Annexes A and B are informative.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following coun-
tries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal,
Slovakia, Spain, Sweden, Switzerland and the United Kingdom.

1)
Directive 97/23 EC of the European Parliament and of the Council of 29 May 1997 on the approximation of the Laws of the
Member States concerning pressure equipment; OIEC L 181.
1 Scope
This European standard specifies requirements for Class designated circular flanges for pipes, valves, fittings and
accessories made from aluminium alloy in the range of DN 15 to DN 600 (NPS 1/2 to NPS 24) and Class 150 to
Class 300 (see Table 1).
This standard specifies the types of flanges and their facings, dimensions and tolerances, bolt sizes, surface finish
of jointing faces, marking and materials together with associated pressure temperature (p/T) ratings.
The flanges are intended to be used for piping as well as for pressure vessels.
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 1515-1, Flanges and their joints — Bolting — Part 1: Selection of bolting.
EN 12392, Aluminium and aluminium alloys — Wrought products — Special requirements for products intended for
the production of pressure equipment.
EN 12560, Flanges and their joints - Gaskets for Class-designated flanges (in different parts)
EN ISO 4287:1998, Geometrical product specification (GPS) — Surface texture: Profile method — Terms, defini-
tions and surface texture parameters (ISO 4287:1997).
EN ISO 6708:1995, Pipework Components — Definition and selection of DN (nominal size) (ISO 6708: 1995).
3 Terms and definitions
For the purposes of this European Standard the following terms and definitions apply:
3.1
DN
see EN ISO 6708:1995
3.2
NPS (Nominal pipe size)
An alphanumeric designation of size for components of a pipework system, which is used for reference purposes. It
comprises, for the purpose of Class designated flanges according to this standard, the letters NPS followed by a
dimensionless number which is indirectly related to the physical size of the bore or outside diameter of the end
connections.
NOTE 1 The number following the letters NPS does not represent a measurable value and should not be used for calculation
purposes except where specified in the relevant standard.
NOTE 2 The relationship between DN and NPS is given in the tables.
3.3
Class
An alphanumeric designation used for reference purposes related to a combination of mechanical and dimensional
characteristics of a component of a pipework system. It comprises the word Class followed by a dimensionless
whole number.
NOTE 1 The number following the word Class does not represent a measurable value and should not be used for calculation
purposes except where specified in the relevant standard.
NOTE 2 The designation Class is not meaningful unless it is related to the relevant component standard number.
NOTE 3 It is intended that all components with the same Class and NPS designations shall have the same mating dimen-
sions for compatible flange types.
3.4
Ra, Rz
see EN ISO 4287:1998
3.5
Maximum allowable pressure, PS
PS means the maximum pressure for which the equipment is designed, as specified by the equipment manufac-
turer.
3.6
Maximum allowable temperature, TS
TS means the maximum temperature for which the equipment is designed, as specified by the equipment manu-
facturer.
4 Designations
4.1 Range of nominal sizes
The range of DN (NPS) applicable to each Class shall be as given in Table 1.
4.2 Range of Class designations
The range of Class designations shall be as given in Table 1.
4.3 Types of flanges
Figure 1 illustrates flanges identified according to type:
a) Type 05 Blank flange;
b) Type 11 Weld-neck flange.
4.4 Designation of flanges
The designation of the flanges shall contain the following information:
a) Description (Flange);
b) Number of this standard (EN 1759-4);
c) Flange type (11, 05 resp.);
d) Flange facing type (e.g. C);
e) DN or NPS (e.g. DN 300);
f) For type 11 flanges only, neck diameter, A and neck thickness, S (e.g. 324 x 5);
g) Class (e.g. Class 150);
h) Material (e.g. EN AW-5083-O).
EXAMPLE 1 For a type 11 flange:
Flange EN 1759-4 - 11 - C - DN 300 - 324 x 5 - Class 150 - EN AW-5083-O
EXAMPLE 2 For a type 05 flange:
Flange EN 1759-4 - 05 - C - DN 300 - Class 150 - EN AW-5083-O
5 General requirements
5.1 Flange materials
Flanges shall be manufactured from the material grades EN AW-5083 (AlMg4,5Mn0,7) -O or EN AW-6061
(AlMg1SiCu) -T6 according to EN 12392. Other materials may be used. For the p/T ratings see 5.5.
Weld-neck flanges shall be forged or made from extruded bars; blank flanges shall be forged or made from plate.
5.2 Repairs
Repair welding of the flanges is not permitted.
5.3 Bolting
5.3.1 The bolting shall be chosen according to the pressure, temperature and gasket.
5.3.2 Bolting materials shall be selected according to the following criteria:
a) For all service conditions in accordance with EN 1515-1 (bolt/nut): 5.6/5, 8.8/8, 25Ni-15Cr-Ti/25Ni-15Cr-Ti,
A4-70/A4-70, A2-70/A2-70, 18Cr-9Ni-Mo-AT+C/18Cr-9Ni-Mo, 18Cr-9Ni-AT+C/18Cr-9Ni;
b) for less severe service conditions e. g. water service or in case of oversized flanged joints, in accordance with
EN 1515-1 (bolt/nut): A4-50/A4-50, A2-50/A2-5
...