Description: Period of time during which an item performs its intended function, it includes all the time a machine is continuously running from start-up until it is shut down.; Name: ot
Description: passed time period after comissioning of a system, sub-system, component or piping; Name: Operating time 
Description: net positive suction head (NPSH) from flow rate at best efficiency point for actual impeller (indication of the minimum inlet pressure in meters required for the pump to deliver according to the QH curve. related to the optimum duty point at the current impeller diameter); Name: net positive suction head for Q opt at actual impeller size