EN 3275:2019

SLOVENSKI STANDARD
01-julij-2019
Nadomešča:
SIST EN 3275:2004
Aeronavtika - Cevni priključek 8°30' do 28 000 kPa - Dinamično tesnilo snopa -
Metrične serije - Tehnična specifikacija
Aerospace series - Pipe coupling 8°30' up to 28 000 kPa Dynamic beam seal - Metric
series - Technical specification
Luft- und Raumfahrt - Rohrverschraubung 8°30' bis 28 000 kPa Dichtlippe - Metrische
Reihe - Technische Lieferbedingungen
Série aérospatiale - Système de raccordement 8°30' jusqu'à 28 000 kPa - Joint à lèvre -
Série métrique - Spécification technique
Ta slovenski standard je istoveten z: EN 3275:2019
ICS:
49.080 Letalski in vesoljski Aerospace fluid systems and
hidravlični sistemi in deli components
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 3275
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2019
EUROPÄISCHE NORM
ICS 49.080 Supersedes EN 3275:2002
English Version
Aerospace series - Pipe coupling 8°30' up to 28 000 kPa
Dynamic beam seal - Metric series - Technical specification
Série aérospatiale - Système de raccordement 8°30' Luft- und Raumfahrt - Rohrverschraubung 8°30' bis 28
jusqu'à 28 000 kPa - Joint à lèvre - Série métrique - 000 kPa Dichtlippe - Metrische Reihe - Technische
Spécification technique Lieferbedingungen
This European Standard was approved by CEN on 5 November 2018.

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, 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 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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 3275:2019 E
worldwide for CEN national Members.

Contents
Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 5
4 Symbols . 7
5 Requirements, inspection and test methods . 7
5.1 Test conditions and preparation of specimens for qualification . 8
6 Quality assurance . 23
6.1 Product qualification . 23
6.2 Quality control records . 23
6.3 Acceptance conditions . 23
6.4 Rejection . 23
6.5 Purchaser’s (user’s) quality control . 24
7 Preparation for delivery . 24
7.1 Cleaning . 24
7.2 Preservation and packaging . 24
Annex A (normative) Production batch identification . 28
A.1 Introduction . 28
A.2 Records . 28
A.3 Example of batch identification . 29
Bibliography . 30

European foreword
This document (EN 3275:2019) has been prepared by the Aerospace and Defence Industries
Association of Europe - Standardization (ASD-STAN).
After enquiries and votes carried out in accordance with the rules of this Association, this Standard has
received the approval of the National Associations and the Official Services of the member countries of
ASD, prior to its presentation to CEN.
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 2019, and conflicting national standards
shall be withdrawn at the latest by November 2019.
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 supersedes EN 3275:2002.
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.
1 Scope
This European standard specifies the required characteristics, inspection and test methods, quality
assurance and procurement requirements for metric series 8°30’ dynamic beam seal pipe couplings, for
temperature ranges type II and III according to ISO 6771 and nominal pressure up to 28 000 kPa.
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 2813, Aerospace series — Aluminium alloy AL-P-6061- — T6 — Drawn tube for pressure
applications — 0,6 mm ≤ a ≤ 12,5 mm
EN 3120, Aerospace series — Titanium alloy TI-P64003 — Cold worked and stress relieved — Seamless
tube for pressure systems — 4 mm ≤ D ≤ 51 mm, 690 MPa ≤ R ≤ 1 030 MPa
m
EN 10204, Metallic products — Types of inspection documents
EN ISO 1302, Geometrical Product Specifications (GPS) — Indication of surface texture in technical
product documentation
ISO 2685, Aircraft — Environmental test procedure for airborne equipment — Resistance to fire in
designated fire zones
ISO 2859-1, Sampling procedures for inspection by attributes — Part 1: Sampling schemes indexed by
acceptance quality limit (AQL) for lot-by-lot inspection
ISO 5855 (all parts), Aerospace — MJ threads
ISO 6771, Aerospace — Fluid systems and components — Pressure and temperature classifications
ISO 6772, Aerospace — Fluid systems — Impulse testing of hydraulic hose, tubing and fitting assemblies
ISO 7137, Aircraft — Environmental conditions and test procedures for airborne equipment
ISO 7257, Aircraft — Hydraulic tubing joints and fittings — Rotary flexure test
ISO 8625-1, Aerospace — Fluid systems — Vocabulary — Part 1: General terms and definitions related to
pressure
ISO 9538, Aerospace series — Hydraulic tubing joints and fittings — Planar flexure test
TR 2674, Design and construction of pipeline for fluids in liquid or gaseous condition — Rigid lines,
installation
1 Published as ASD-STAN Prestandard at the date of publication of this standard by AeroSpace and Defence
industries Association of Europe – Standardization (ASD-STAN) (www.asd-stan.org).
2 Published as ASD-STAN Technical Report at the date of publication of this standard by AeroSpace and Defence
industries Association of Europe – Standardization (ASD-STAN) (www.asd-stan.org).
MIL-H-5606, Hydraulic fluid, Petroleum Base, Aircraft, Missile and Ordnance
MIL-H-8446, Hydraulic fluid, Nonpetroleum Base, Aircraft
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
 ISO Online browsing platform: available at http://www.iso.org/obp
 IEC Electropedia: available at http://www.electropedia.org/
3.1
pressure
nominal pressure, proof pressure, impulse pressure, burst pressure according to ISO 8625-1
3.2
coupling
3.2.1
coupling assembly
assembled and torque-tightened nut, ferrule and pipe mating with e.g. unions, tees or elbows
Note 1 to entry: See Figure 1.

Key
1 dynamic beam seal
2 ferrule
3 nut
4 union end
Figure 1 — Example of coupling assembly
3.2.2
straight coupling
union connecting pipe to pipe
3 Published by: Department of Defense (DoD), the Pentagon, Washington, D.C. 20301.
3.2.3
forged parts
shaped parts
couplings machined out of individual forging blanks
Note 1 to entry: For crosses, tees and elbows machined out of bar or plate stock the term “shaped” may be used.
3.3
surface defects
3.3.1
surface irregularity
nonconformity with general surface appearance, possible defect
3.3.2
crack
clean (crystalline) fracture passing through or across the grain boundaries that possibly follows
inclusions of foreign elements
Note 1 to entry: Cracks are normally caused by overstressing the metal during forging or other forming
operations, or during heat treatment. Where parts are subject to significant reheating, cracks are usually
discoloured by scale.
3.3.3
fold
doubling over of metal, which can occur during the forging operation
Note 1 to entry: Folds can occur at or near the intersection of diameter changes and are especially prevalent
with non-circular necks, shoulders and heads.
3.3.4
lap
fold-like machining defect
3.3.5
seam
(1) usually a surface opening or crack resulting from a defect obtained during casting or forging
(2) extraneous material, stringer in the material, which is not homogeneous with base metal
3.3.6
pit
void or hole in the surface as caused, for example, by corrosion
3.4
quality assurance
3.4.1
production batch
definite quantity of some commodity or service produced at one time under conditions that are
presumed uniform
3.4.2
delivery batch
batch consisting of couplings with the same identity block which may come from different production
batches
3.4.3
acceptable quality level
AQL
when a continuing series of lots is considered, a quality level which for the purposes of sampling
inspection is the limit of a satisfactory process average
3.4.4
qualification
testing required to demonstrate successful performance of the coupling assembly in simulated service
(overload, destructive and fatigue tests)
3.4.5
major defect
defect other than critical, that is likely to result in a failure or to reduce materially the usability of the
considered product for its intended purpose
3.4.6
minor defect
defect that is not likely to reduce materially the usability of the considered product for its intended
purpose, or that is a departure from established specification having little bearing on the effective use
or operation of this product
4 Symbols
A Elongation, in percent [%]
D Actual outside diameter of pipe, in millimetres [mm]
D Actual inside diameter of pipe, in millimetres [mm]
DN Nominal outside diameter of pipe
P Working pressure, in megapascals [MPa]
R Tensile strength, in megapascals [MPa]
m
R 0,2 % proof stress, in megapascals [MPa]
p0,2
σ Axial stress due to pressure, in megapascals [MPa]
x
5 Requirements, inspection and test methods
See Table 1 and Table 2.
5.1 Test conditions and preparation of specime
...