PUMP TYPES P051
There is no end to the variety of pumps available today. Here is a listing of some of the common centrifugal types you will be using:
|The end suction centrifugal pump.The fluid enters the horizontal inlet and discharges out the vertical outlet.|
Centrifugal pumps account for about 90% of the pumps used in industry. In the United states about 85% of these pumps are supplied with open impellers. In Europe most centrifugal pumps are supplied with closed impellers
|The end suction centrifugal, double volute pumpThe double volute design was created to reduce shaft deflection problems when the pump is operating off its best efficiency point (BEP).|
Because of its lower efficiency, the double volute design has just about disappeared in the smaller size pumps.
|Horizontally split double ended pump Double ended pumps are specified:|
- For higher capacity.
- If you need a lower net positive suction head required (NPSHR) than that required for end suction centrifugal pumps.
|Vertical, inline pumpThese pumps take up very little floor space and eliminate most pipe strain problems.|
Most of them are close coupled or come equipped with a “C or D” frame adapter eliminating the need for alignment with the motor.
|Vertical turbine pump, Sometimes called a deep well pump. These pumps were originally made for pumping deep wells. They have been made for heads as high as 1000 feet (300 meters) and capacities as high as 25000 gpm (5700 m3/hr)|
These pumps are normally equipped with sleeve or journal bearings.
|Self-priming, end suction centrifugal pump. The main purpose of these pumps is to remove any air that might be entrained on the suction side of the pump that will prevent the pump from functioning.|
|The closed impeller pump. This design is widely used in oil refineries or any application where the product is explosive. The soft wear rings provide a safety feature in the event the pump experiences a bearing failure.|
|The close coupled pump. |
This design eliminates alignment problems. The pump shaft is an extension of the motor shaft.
Unfortunately most commercially available close coupled pumps have too large an L3/D4 shaft number.
|Double ended, multi stage pump |
Multistage pumps are the logical method of providing a high head pump any time you need a decent capacity.
Rotary or positive displacement pumps can provide the high head if the capacity is low.