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Installation
■ Suction line
1. Always build up a flooded suction system. Have a suction line shortest with the minimum number of bends. Support
piping by pipe supports so that the pump is not subject to piping weight or thermal stress.
2. Make sure joints on a suction line are secure and air doesn't come in. If air is entrained into a suction line, liquid
may not be pumped or the pump may break at its worst.
3. When the inner pressure of a supply tank is negative, or a suction lift or a suction line is long, apply the following
formula.
NPSHa>NPSHr+0.5m (See the standard performance curve for NPSHr.)
4. If a bent pipe is installed in a suction line, lay a straight line (length: 500mm or longer, or 8 times longer than the
inlet I.D. of the pump) between a pump inlet and the bent pipe. Also, have the curvature radius of the bent pipe larg-
est.
5. Do not allow any arched line where air may be trapped. A suction line should be laid on a rising gradient of 1/100
toward the pump.
6. If the inlet I.D. of the pump is different from that of a suction pipe, use an eccentric reducer pipe. Upper side should
always be level. Air may be trapped if it is mounted upside down.
Load direction
Pipe dia. (mm)
25
Moment
40, 50
0.05
0.10
0.02
0.05
0.05
0.10
kN·m
Mx
My
Mz
Load direction
Pipe dia. (mm)
25
Moment
40
0.02
0.05
0.05
0.10
0.05
0.10
kN·m
Mx
My
Mz
Load direction
Pipe dia. (mm)
25
Load
40
0.10
0.15
0.15
0.20
0.10
0.10
0.10
0.15
kN
Fx
Fy: compression
Fy: tension
Fz
Load direction
Pipe dia. (mm)
25
Load
40, 50
0.10
0.10
0.10
0.15
0.10
0.15
kN
Fx
Fy
Fz
Permissible stress to outlet flange
Permissible stress to inlet flange
Permissible moment to outlet flange
Permissible moment to inlet flange
