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Suction piping
1. Flooded suction system
Always realize the flooded suction system.
2. Suction piping bore
A suction piping bore should be equal to or larger than pump inlet.
3. Shortest piping length
Have piping shortest with the minimum number of bends.
4. Straight pipe length
The piping end right before the pump inlet should be straight.
When the pump inlet bore is 50A or smaller, the straight pipe length should be of 500 mm or longer
When the pump inlet bore is 65A or larger, the straight pipe length should be eight times longer than inlet
bore. For the easy pump removal and maintenance, install a removable pipe of 300mm in straight piping.
5. Air pocket
Do not make any projection or arched line where air may be trapped.
The suction pipe should be laid on a rising gradient of 1/100 toward the pump.
6. Use of the eccentric reducer pipe
If the pump inlet bore is different from that of suction pipe, use the eccentric reducer pipe. Upper side
should always be level. The air may be trapped if it is mounted upside down.
7. Gate valve installation
In flooded suction, install a gate valve on the suction piping for easier overhaul & inspection.
8. Flushing piping
Install the flushing piping for cleaning the pump when handling a harmful liquid.
9. Suction piping end
The suction piping end should always be at least 500 mm lower than a liquid level for the prevention of the
air ingress.
10. In a piping system other than the flooded suction
• The distance between the end of suction piping and the bottom of a suction tank should be 1 to 1.5
times wider than the suction pipe bore.
• Be sure to install a foot valve or a check valve on the suction piping.
11. Piping support
Support piping by pipe supports so that the pump is not subject to piping weight or thermal stress.
12. Connections
Each connection must be completely sealed so that air can not be sucked in. Imperfect sealing can cause
the air ingress and it results in the insufficient suction and the seizure of bearing.
Installation
