DOUBLE ENDED PUMP D021
A two-stage design is shown in the illustration.
- In this design there are bearings on either end of the pump, allowing you to use a wide impeller for high capacity applications
- These pumps are available in single or multistage designs.
- Multistage designs have multiple impellers installed on the pump shaft, with the discharge of the first impeller directed to the suction of the next impeller.
- This design allows the manufacturer to build a pump with a high head and a low capacity.
- Most API 610 applications use radially split casings rather than axial split because of potential problems with the larger axial split gasket.
- When the casing halves become distorted, both halves must be re-milled flat and then should be line bored. Line boring is frequently left out.
- API limits low flow to 60% of BEP with 70% preferred, and on the right side, 120% with 110% preferred.
A 90° elbow too close to the inlet can cause uneven flow to one of the impeller eyes. This could cause cavitation on one side and recirculation damage on the other, along with vibration and unstable operation. Pump manufacturers often reduce the requirement of 8-10 diameters of straight pipe at the inlet by recommending anti-vortexing devices to rectify the flow