Samson 3241, Монтаж и эксплуатация

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32 EB 8012 EN
Mounting and start-up
Vent plug
Vent plugs are screwed into the exhaust air
ports of pneumatic and electropneumatic de-
vices. They ensure that any exhaust air that
forms can be vented to the atmosphere (to
avoid excess pressure in the device). Further-
more, the vent plugs allow air intake to pre-
vent a vacuum from forming in the device.
Î
Locate the vent plug on the opposite side
to the workplace of operating personnel.
Î
On mounting valve accessories, make
sure that they can be operated from the
workplace of the operating personnel.
Note:
The workplace of operating person-
nel is the location from which the
valve, actuator and any mounted
valve accessories can be accessed to
operate them.

Table 6: Inlet and outlet lengths
Q
a x NPS b x NPS
State of process
medium
Valve conditions Inlet length a Outlet length b
Gas
Ma ≤ 0.3 2 4
0.3 ≤ Ma ≤ 0.7 2 10
Vapor
Ma ≤ 0.3
1)
2 4
0.3 ≤ Ma ≤ 0.7
1)
2 10
Saturated steam (percentage of condensate
> 5 %)
2 20
Liquid
Free of cavitation/w < 10 m/s 2 4
Cavitation producing noise/w ≤ 3 m/s 2 4
Cavitation producing noise/3 < w < 5 m/s 2 10
Critical cavitation/w ≤ 3 m/s 2 10
Critical cavitation/3 < w < 5 m/s 2 20
Flashing – 2 20
Multi-phase – 10 20
1)
No saturated steam
Q Flow rate
a Inlet length
b Outlet length