| 摘要 |
A piston prover comprises a measurement cylinder; a hydraulic cylinder coupled with a downstream end of the measurement cylinder; a measuring piston that moves a predetermined distance through the measurement cylinder during a measurement due to a fluid flow to eject a reference volume of fluid; and a piston rod that is movably in the hydraulic cylinder, wherein the measuring piston and the piston rod are separately constructed, When returning the measuring piston to a predetermined upstream measurement standby position, the piston rod moves the measuring piston to set the measuring piston at the predetermined measurement standby position, and thereafter only the piston rod is moved from upstream to downstream and is accommodated in the hydraulic cylinder. |
