Samson EB 8075 EN, Монтаж и эксплуатация

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EB 8075 EN 5-15
Installation
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 yoke indicates whether an ad-
justable packing is installed (see the 'Mark-
ings on the device' section).
Risk of valve damage due to the use of un-
suitable tools.
A special tool is required for form HT pack-
ings.
Î
Contact our after-sales service.
Impaired valve functioning due to increased
friction as a result of the threaded bushing
being tightened too far.
Î
Make sure that the piston stem can still
move smoothly after the threaded bush-
ing has been tightened.
1. Up to NPS 16 (Class 150): tighten the
threaded bushing gradually (by turning it
clockwise) until the packing seals the
valve.
NPS 16 and larger (Class 300 and
higher): tighten the nuts on the packing
gland in a crisscross pattern (by turning
them 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.
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.
Î
Check the travel reading at the travel in-
dicator scale.
5.4.3 Fail-safe position
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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.
NOTICE
!
NOTICE
!
Tip