Supplementary Plant Lay-Out Instructions - LP121HT PUMP
Pressure in Inlet Side
The stipulated NPSHR is the minimum required pressure above the vapor pressure of the medium and is never to fall short of this figure. Temperature and vapor pressure of the medium, the geodetical height of the location, the flow rate and the loss of friction in the suction line, must all be taken into consideration. It may be necessary to install a booster pump (centrifugal) in the suction line.
Pulsation
Due to its construction, the plunger pump creates pulsation in the inlet and discharge lines. In particular, inlet pulsation must be dampened in order to prevent resonance in the suction line which in turn causes cavitation. Therefore, the pump is never to be connected by a rigid pipe. Rather, use a flexible hose, which is not reinforced by steel, that is 1.5 to 2 times wider than the inlet port. If a booster pump is used, the hose is to be attached between the booster pump and the high pressure pump.
If several pumps are used, each pump must have its own inlet line. If this cannot be done, an inlet air chamber or inlet flow stabilizer must be installed in front of each pump. The bladder in the stabilizer is to be
Depending on the layout of the plant, a pressure accumulator may be necessary on the discharge side. The pressure accumulator must be installed right behind the discharge outlet of the high pressure pump. Only use one pressure accumulator (in the discharge line) at a time in order to avoid irritation which could be caused by different pretension levels in the accumulators.
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