TESTING OF PIPES EXPLAINED IN BRIEF
TESTING OF
PIPES & Backfilling
The pressure
test must be carried out in compliance with the requirements laid down in the
relevant rules and regulations, e.g. for gas pipelines the DVGW Worksheet G 469
and/or the VdTÜV Data Sheet 1060 and for gas pipelines up to 16 bar, EN 12327.
The example set
out below illustrates the pressure test for water pipelines in compliance with
EN 805 and/or DVGW Worksheet W 400-2.
Each pipeline
must be subjected to a pressure test after it has been laid. Pressure tests
must be carried out by qualified personnel with the relevant knowledge of
pipeline engineering, the execution of pressure tests, the measurement
techniques and the applicable safety regulations.
Before the
pressure test can be carried out, the pipeline must be covered with backfill
material so as to avoid shifts in position, which could cause leaks. This
applies in particular to pipelines with mechanical socket connections. The
joints need not be covered by backfill. The pipeline is to be tested over its
entire length or, if necessary, in sections. The test sections must be defined
so that:
the test pressure is reached at
the deepest point of each test section
and a pressure of at least 1.1
times the maximum design pressure (MDP) is reached at the highest point.
The system test
pressure (STP) can be calculated on the basis of the MDP as follows: