Centrifugal pumps tests
The high economic cost inherent in the energy consumption necessary for its operation and that derived from its deterioration, make it necessary to have precise knowledge of its characteristic performance curves.
Usually grade 1 centrifugal pumps are only tested in the factory (FAT) under the requirements of the relevant standard (e.g. ISO 9906); the tests, checks and trials carried out in this way, particularly hydraulic efficiency, are carried out under ideal conditions which may vary substantially from the actual operating conditions of the pump already on site, and it is therefore recommended that pump acceptance is based on the results of the tests carried out on site rather than in the factory.
On-site centrifugal pumps tests (SAT) are carried out both for their definitive acceptance and for their periodic control, verification of their correct selection, determination of the origin of low performance, calculation of load losses, study of the behaviour of the variable frequency drive, etc. Tests are carried out in accordance with the standard specified by the customer: ISO 5198, ANSI/HI 14.6, AWWA E-103-15, ISO 13709, NFPA25, etc., in a range up to 700 m in height. In addition, vibration measurements are carried out in accordance with ISO 10816-7.
The measurement methods for determining the pump's main characteristic curves (head-flow, power-flow and efficiency-flow) are thermodynamic and acoustic transit time. In general, measured parameters are: flow rate, intake pressure, discharge pressure, atmospheric pressure, inlet level, air temperature, water temperature, pump rotational speed, instruments levels and electrical power consumed by the motor.