1.6.1 Inspection and care of pumps

Inspection and care of pumps

The inspection of a pump unit should be carried out according to a definitive routine. The intervals required are dependent on the working conditions and environment of the pump and the demands of operational reliability. Periods exceeding one week are inadvisable, especially in the case of pumps separately erected and lacking alarm systems. Observations such as listening and feeling for vibrations, and checks on pressure, flow and power consumption, if measuring instruments are provided for the purpose, should be performed in connection with every inspection in addition to the checking of packings. More detailed investigation should, of course, be undertaken if deviations from normal operation are noted. Section 1.6.4 reviews a fault-detecting programme which may provide guidance for this purpose.

If several pumps are included in the system, the starting sequence switch should be adjusted so that the running time is divided between all the units. Automatic and alarm devices should also be regularly tested.

Dosing pumps often require special checks with regard to flow measurement, necessitating the use of graduated vessels or other measuring equipment, and also the testing of control equipment.

The concept of care may include the external cleaning of pump and motor in addition to the cleaning of screens and filters on the suction side and in pump sumps. The necessary cleaning of pump casings and impellers may
also be classed under the same heading. This work may be extensive, depending on the of pump. The possibility of reversing the direction of rotation of the pump or regular reverse flushing can considerably reduce trouble
caused by blockage. This kind of cleaning of the casing and impeller neæssitates that the unit can tolerate a certain amount of reverse rotation, which should be checked with the supplier and that care should be exercised.