Samson 3595, Mounting And Operating Instructions

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EB 8079 EN 5-3
Installation
Table 5-1: Inlet and outlet lengths
Q
a x NPS b x NPS
Q Flow rate
a Inlet length
b Outlet length
State of
process
medium
Valve conditions
1) 2)
Inlet length
a
Outlet length
b
Gas
Ma ≤ 0.3 2 4
0.3 ≤ Ma ≤ 0.7 2 10
Vapor
Ma ≤ 0.3
3)
2 4
0.3 ≤ Ma ≤ 0.7 3) 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)
Ma: Mach number (dimensionless quantity for velocity)
2)
w: Flow velocity
3)
No saturated steam