Samson 3321CT, Монтаж и эксплуатация

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EB 8115 EN 5-7
Installation
To test the valve functioning before start-up
or putting back the valve into operation, per -
form the following tests:
5.4.1 Leak test
The plant operator is responsible for per -
forming the leak test and selecting the test
method. The leak test must comply with the
requirements of the national and internation
-
al standards that apply at the site of installa -
tion.
Our after-sales service can support you to
plan and perform a leak test for your plant.
1. Close the valve.
2. Slowly apply the test medium to the inlet
space upstream of the valve. Avoid sud-
den surges in pressure since the resulting
high velocities may damage the valve.
3. Open the valve.
4. Apply the required test pressure.
5. Check the valve for leakage to the atmo-
sphere.
6. Depressurize the pipeline section and
valve.
7. Rework any parts that leak and repeat
the leak test.
5.4.2 Travel motion
The movement of the actuator stem must be
linear and smooth.
Î
Apply the maximum and minimum con-
trol signals to check the end positions of
the valve while observing the movement
of the actuator stem.
5.4.3 Fail-safe position
Î
Shut off the signal pressure line.
Î
Check whether the valve moves to the
fail-safe position (see the 'Design and
principle of operation' section).
5.4.4 Pressure test
The plant operator is responsible for per -
forming the pressure test.
Our after-sales service can support you to
plan and perform a pressure test for your
plant.
During the pressure test, make sure the fol -
lowing conditions are met:
− Retract the plug stem to open the valve.
− Observe the maximum permissible pres-
sure for both the valve and plant.
Tip
Tip