Samson 3256, Mounting And Operating Instructions, Page: 42 / 84

5-16 EB 8065 EN
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. A sudden
surge in pressure and resulting high ve-
locities can 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 (see informa-
tion below under ‘Adjusting the packing’)
and repeat the leak test.
Adjusting the packing
A label on the flange or yoke indicates
whether an adjustable packing is installed
(see the 'Markings on the device' section).
Impaired valve functioning due to increased
friction as a result of the threaded bushing
being tightened too far.
Î
Make sure that the plug stem can still
move smoothly after the threaded bush-
ing has been tightened.
1. Tighten the threaded bushing gradually
(by turning it clockwise) until the packing
seals the valve.
2. Open and close the valve several times.
3. Check the valve for leakage to the atmo-
sphere.
4. Repeat steps 1 and 2 until the packing
completely seals the valve.
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If the adjustable packing does not seal
properly, contact our after-sales service.
Tip
NOTICE !