Description: Period of time from the commissioning of a plant, part of a plant, a component or a line system; Name: service life
Description: passed time period after comissioning of a system, sub-system, component or piping; Name: Operating time 
Description: Determined proportion of pump available power input, Pa, which is delivered as pump power output, Pu, after satisfying the losses resulting from friction due to the relative motion of internal surfaces and internal leakage ; Name: Hydraulic efficiency