Johnson Pump SPX Flow CombiLineBloc, Instruction Manual

Page: 30 / 67

28 Commissioning
CLB/EN (1901) 6.6
4.5 Pump in operation
When the pump is in operation, pay attention to the following:
• The pump should never run dry.
• Never use a stop valve in the suction line to control pump output. The stop valve
should always be fully opened during operation.
• Check whether the absolute inlet pressure is sufficient, to prevent vaporization in the
pump. Vaporization may cause cavitation.
!
Cavitation should always be prevented since it causes serious damage to the
pump!
• Check whether the pressure difference between suction and delivery side
corresponds with the specifications of the pump's duty point.
• A mechanical seal may never show visible leakage.
4.6 Noise
The noise production of a pump depends to a great extent on the operating conditions.
The values stated in paragraph 10.4 "Noise data" are based on normal operation of the
pump, driven by an electric motor. In case the pump is driven by a combustion engine, or
in case it is used outside the normal operation area, as well as in case of cavitation, the
noise level may exceed 85 dB(A). In that case precautions should be taken, like building
a noise-barrier around the unit or wearing hearing protection.