Spare Parts

Maintenance Manual


Commissioning and Maintenance Instructions :

Polyhydron make Radial Piston Pumps are reliable hence require very little attention from user. However it is necessary that following points must be kept in mind while storage, assembly, commissioning and maintenance.

Storage :

For open execution type, it is necessary that during storage the pumps must be properly covered and well lubricated. This will prevent the ingress of dust/dirt in the working mechanism and during commissioning it will be easy to install the same.

Assembly :

During assembly take care to align the pump properly with respect to the electric motor or other driving mechanism.

Badly aligned pumps will damage the bearings very fast.

Badly machined flexible couplings will damage the bearings and the key in very short time. The flexible couplings used to drive the pump must be of good quality.

For open execution type it is necessary that the pumps must be properly immersed in the oil for its efficient and smooth working. The proportions of the tank should be adequate so that even after the maximum displacement of the oil from the tank the oil level should not fall below the minimum level for the pump. Please remember that the pump always needs its suction valves flooded with oil.

For casing pumps the maximum negative suction head should not exceed 300 mm. The suction pipe should be 16 O.D x 3 mm Th. and preferably straight.

Commissioning :

During commissioning, the pumps do not need any special attention. But if it is stored for a long time it is likely that it’s suction valves may not operate properly (open execution pump). In such cases remove the suction nut by applying 5 kg-m torque and clean the suction valve assembly with kerosene. These cleaned suction valves are again put back in the cylinders. Ensure 5 kg-m torque is reapplied.

For casing type ensure the total removal of air inside the casing.

The direction of rotation of the pump is not important. However if the pump is coupled to any other make pump, then the direction of rotation of the pump depends on the coupled pump.

Maintenance :

The radial piston pumps do not need any major attention, but to ensure its efficient working and long life of the pump it is necessary that the following points kept in mind:

The oil must be of prime quality and clean as per ISO code 16/13.

Care should be taken that the oil should be periodically changed. The use of Contaminated oil may damage suction valves and bearings.

For optimum performance the viscosity of the oil at operating temperature should be in the range of 40 – 70 cSt.

In case if you disassemble the pump use 5 kg-m torque for tightening the cap screws.


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78-80, Machhe Industrial Estate, Machhe, Belgaum - 590 014. Karnataka, INDIA. 
Phone :
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Updated on May 13, 2010 02:32 pm .