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: pump h(q) curve where the maximum head (peak point) and shut-off head are not coincidental, or the total head does not decline continuously as the rate of flow increases; Name: stable pump H(Q) curve