Rotary piston pumps components

The various components of a rotary piston pump are shown in Figure 2.12. 

Figure 2.12 Arrangement of Components in a Rotary Piston Vacuum Pump...

There is also a much more compact and low-cost option - based on the pump manufacturer concept . This concept has been tried and tested for decades in oil-lubricated rotary piston vacuum pumps - so why not in LRVPs. There is no need for extensive frame constructions for mounting system components. Costintensive pipes required for manufacturing previous units, as well as throughout the service life, are no longer required. Components can be retrofitted easily. 

Positive-displacement pumps and those that approach positive displacement will ideally produce whatever head is impressed upon them by the system restrictions to flow. The maximum head attainable is determined by the power available in the drive (slippage neglected) and the strength of the pump parts. A pressure relief valve on the discharge side should be set to open at a safe pressure for the casing and the internal components of the pump such as piston rods, cylinders, crankshafts, and other components which would be pressurized. In the case of a rotary pump, the total dynamic head developed is uniquely determined for any given flow by the speed at which it rotates. 

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