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© 05.2022
US
Ga
s-D
ru
ck
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lg
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t
DEN
US
Ga
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7.10
7.09
7.10
7.09
For Germany:
According to DVGW work sheet G 491, the fully assembled system must be subjected to a leakage test with air or an inert
gas at the installation site, using 1.1 times the maximum operating pressure of the system (MOP).
An exception is the room between the actuator and the first shut-off valve on the outlet side. This room must be checked
using the test pressure corresponding to the maximum permissible pressure in the system in case of a malfunction (1.1
MOP
d
). In this test, all detachable connections must be checked using a foaming agent.
In direct-acting devices (without power supply), the outlet pressure acting on the actuator should not
be more than 0.5 bar above the set setpoint. This should be taken into account when specifying the
response pressure of the upstream SSVs.
Recommended upper response pressures:
•
p
d
≤
100 mbar
p
dso
= P
d
+ 50 mbar
•
p
d
> 100 - 200 mbar p
dso
= P
d
+ 100 mbar
•
p
d
> 200 - 1000 mbar p
dso
= P
d
x 1,5
•
p
d
> 1000 mbar
p
dso
= p
d
+ 500 mbar
For other countries:
The relevant national and international standards shall apply.
Procedure
•
Close the ball valve upstream of the valves and fittings (item 7.01).
•
Close the downstream shut-off devices (item 7.13) (ball valve,
solenoid or pneumatic valve).
•
Depressurize the system (item 7.11).
•
If there is a SRV (safety relief valve) in the controlled section and
the test pressure is higher than the relief pressure of the SRV (item
7.09), the line upstream of the SRV (item 7.10) must be closed.
•
Connect the testing device to measuring points upstream and
downstream of the gas pressure regulator (items 7.02 / 7.12).
•
Always increase the test pressure slowly and steadily
(max. 500 mbar/sec.)
7.3 Leakage Test (Test for External Leakage)
The devices are subjected to a strength and leakage test ex works at MEDENUS Gas-Druckregeltechnik GmbH.
The leakage test in the fully assembled system must be performed prior to commissioning and following maintenance
work.
For the external leakage test in the fully assembled system, the following applies:
While doing so, you must ensure:
Pressure in outlet chamber (item 7.12)
≤
pressure in inlet chamber (item
7.02)
Pressure build-up always from the inlet side (inlet chamber)
Pressure reduction always from the outlet side (outlet chamber)
•
After
leakage
test:
O p e n
the ball valve in the SRV line (item 7.10) again.
Note
ATTENTION
Note