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[3] When installing a valve on the suction pipe, select a valve with an orifice larger than the inner diameter of the said
pipe. A smaller orifice may result in a larger suction piping resistance or an increased chance for the valve to be
clogged with a crystallized substance. Make sure to keep the valve open during pump operation.
Caution
Operating the pump with the valve on the suction pipe increases the pressure inside the bellows to deform the
bellows inwardly.
2.2.2 Points to be observed in discharge pipe arrangement
[1] The pump discharge load increases with the length of the discharge pipe or the number of bends along the pipe. In
order to decrease the load install a dampener which minimizes pulsation.
[2] When installing a valve in the discharge pipe, select a valve with an orifice whose diameter is larger than that of the
inner diameter of the pipe. A valve with a smaller diameter may increase the discharge piping resistance or easily
be clogged with crystallized substance. Keep the valve open when the pump is in operation. Do not close the valve
until the discharge pressure reaches "0" after the pump is stopped.
Caution
Do not close the valve before stopping the pump. The resulting impactive pressure may deform the bellows.
[3] A filter must be selected to meet the pump type.
Filtering area, grain-removing performance, and flow characteristics should be taken into consideration in selecting
the filter. Desired flow rate may not be achieved if the selection is wrong.
Caution
The filter should be dampened well before running operation liquid. A desired flow rate may not be achieved if the
filter is not dampened well.
The filter dries out if the operation liquid is not supplied for a long time. Make sure to dampen the filter prior to pump
operation. Read the instruction manual of the filter for the details.
[4] The piping should be designed in a manner that no residual pressure results on the discharge side upon stopping the
pump.
(For example, filter air elimination shall be set full open or a return circuit shall be employed to remove residual
pressure.)
Caution
Residual pressure on the discharge side upon stopping the pump may deform the bellows.
