Welding Fabrication Standards - EWF

Welding Fabrication Standards Page 68
7.3 EN 12732: Quality requirement categories
The standard considers different categories of pipelines, depending on which the requirements to
comply with are identified. Table 14 reports this assignment based on the materials used and on
the operating pressure.
Category
A
B
Operating
pressure
Lower than
100 mbar
100 mbar up to
5 bar
C 5 bar up to 16 bar
D Higher than 16 bar
Base material Example of use
C and C-Mn steels,
with Rs≤360Mpa*
C and C-Mn steels,
with Rs≤360Mpa*
C and C-Mn steels,
with Rs≤360Mpa*
Low alloyed C, C-Mn,
microalloyed and quenched
and tempered steels**
NOTES
* Steels classified as Group 1 according to CR ISO 15608 and reported in EN 10208
** Steels classified as Group 1 to 3 according CR ISO 15608 and reported in EN 10208
Table 14 – Allocation to quality requirements categories
Mains and service pipes in gas supply
systems
Mains and service pipes in gas supply
systems, pipework in stations
Pipeline including pipework in stations
and gas distribution systems
Pipeline including pipework in stations
and gas distribution systems
However, depending on particular conditions, such as materials used, line routing, design or
welding techniques, higher or lower quality categories can be assigned in order to identify the more
coherent quality requirements.
7.4 EN 12732: requirements on quality systems
Depending on the quality requirement category, some specific requirements on the application of
quality systems are identified by the standards.
This involves the application of an appropriate quality level of EN ISO 3834, the qualification grade
of the welding coordinator, the NDT personnel and the approval of welding procedures; giving the
exact interpretation and integrating the clauses of EN ISO 3834.
Table 15 reports a summary on the recommended quality requirements to be fulfilled.
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