FP USER INSTRUCTIONS ENGLISH 71576286 - 07/06
Shutdown:
Close the outlet valve and stop the motor. Eventually close the inlet valve.
For prolonged shutdowns and especially when ambient temperatures are likely to drop below freezing point, the pump and any cooling and flushing arrangements must be drained or otherwise protected.
5.7Hydraulic, mechanical and electrical duty
NPSH required (NPSHR) is the minimum head required at the impeller inlet, above the vapour pressure of the pumped liquid, to avoid excessive cavitation and extreme performance degradation.
It is important that NPSHA > NPSHR. The margin between NPSHA > NPSHR should be as large as possible.
If any change in NPSHA is proposed, ensure these margins are not significantly eroded. Refer to the pump performance curve to determine exact requirements particularly if flow has changed.
This product has been supplied to meet the performance specifications of your purchase order, however it is understood that during the life of the product these may change. The following notes may help the user decide how to evaluate the implications of any change. If in doubt contact your nearest Flowserve office.
5.7.1 Specific gravity (SG)
Pump capacity and total head in meters (feet) do not change with SG, however pressure displayed on a pressure gauge is directly proportional to SG. Power absorbed is also directly proportional to SG. It is therefore important to check that any change in SG will not overload the pump driver or
5.7.2 Viscosity
For a given flow rate the total head reduces with increased viscosity and increases with reduced viscosity. Also for a given flow rate the power absorbed increases with increased viscosity, and reduces with reduced viscosity. It is important that checks are made with your nearest Flowserve office if changes in viscosity are planned.
5.7.3 Pump speed
Changing pump speed effects flow, total head, power absorbed, NPSHR, noise and vibration. Flow varies in direct proportion to pump speed, head varies as speed ratio squared and power varies as speed ratio cubed. The new duty, however, will also be dependent on the system curve. If increasing the speed, it is important therefore to ensure the maximum pump working pressure is not exceeded, the driver is not overloaded, NPSHA > NPSHR, and that noise and vibration are within local requirements and regulations.
5.7.4 Net positive suction head (NPSHA)
NPSH available (NPSHA ) is the head available at the impeller inlet, above the vapour pressure of the pumped liquid.
If in doubt please consult your nearest Flowserve office for advice and details of the minimum allowable margin for your application.
5.7.5 Pumped flow
Flow must not fall outside the minimum and maximum continuous safe flow shown on the pump performance curve and or data sheet.
5.8Pumps for Food Use or Potable Water
If the pump has not been specifically ordered for a food or drinking water application it must not be used for these types of applications. If it has been ordered for this type of application the following recommendations are to be followed.
5.8.1 Cleaning prior to operation
Pumps that are to be used for a food or drinking water application should be cleaned before being put into initial operation and after the installation of spare parts that are in contact with the liquid.
Cleaning once the pump has been commissioned will depend on the application and operating conditions. The user must ensure that the cleaning procedures are suitable for the application and operating conditions, and local regulations.
6MAINTENANCE 6.1 General
If a belt drive is used, the assembly and tension of the belts must be verified during regular maintenance procedure.
In dirty or dusty environments, regular checks must be made and dirt removed from areas around close clearances, bearing housings and motors.
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