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prБДС EN 10253-4:2021

Butt-welding pipe fittings - Part 4: Wrought austenitic and austenitic-ferritic (duplex) stainless steels with specific inspection requirements

General information

60.55     May 30, 2021




European Standard

23.040.40     77.140.20  


This document specifies the technical delivery requirements for seamless and welded butt-welding fittings (elbows, concentric and eccentric reducers, equal and reducing tees, caps) made of austenitic and austenitic-ferritic (duplex) stainless steel in two test-categories which are intended for pressure purposes at room temperature, at low temperature or at elevated temperatures, and for the transmission and distribution of fluids and gases.
It specifies:
a) type of fittings;
1) type A: butt-welding fittings with reduced pressure factor;
2) type B: butt-welding fittings for use at full service pressure;
b) steel grades and their chemical compositions;
c) mechanical properties;
d) dimensions and tolerances;
e) requirements for inspection and testing;
f) inspection documents;
g) marking;
h) protection and packaging.
NOTE The selection of the appropriate fitting (material, thickness) is the ultimate responsibility of the manufacturer of the pressure equipment (see European Legislation for Pressure Equipment). In the case of a harmonized supporting standard for materials, presumption of conformity to the ESRs is limited to technical data of materials in the standard and does not presume adequacy of the material to a specific item of equipment. Consequently, it is essential that the technical data stated in the material standard be assessed against the design requirements of this specific item of equipment to verify that the ESRs of the PED are satisfied.

Directives and Regulations

When the standard is harmonized under a directive or regulation, the word Harmonized appear. When such an inscription does not appear, it means that the standard is related to / supporting the relevant directive or regulation.


Directive 2014/68/EU of the European Parliament and of the Council of 15 May 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of pressure equipment

Life cycle


БДС EN 10253-4:2009


prБДС EN 10253-4:2021
60.55 Ratification completed (DOR)
May 30, 2021

Related project

Adopted from EN 10253-4:2021


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