Samson 3254, Mounting And Operating Instructions

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5-2 EB 8060 EN
Installation
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 work position of operating person-
nel.
Valve accessories
Î
During connection of valve accessories,
make sure that they are easily accessible
and can be operated safely from the
work position.
5.2 Preparation for installation
Before installation, make sure the following
conditions are met:
− The valve is clean.
− The valve and all valve accessories (in-
cluding piping) are not damaged.
− The valve data on the nameplate (type
designation, valve size, material, pres-
sure rating and temperature range)
match the plant conditions (size and
Table 5-1: Inlet and outlet lengths
Q
a x DN b x DN
State of pro -
cess 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