Meter provers and methods of proving flow meters

摘要

A meter prover has a linearly displaceable piston 15 which is associated with a position encoder 24 adapted to provide signals denoting increments of movement of the piston along a cylinder during a proving run. The beginning and end of the proving run are defined by pulses from the meter 2 and in particular pulses which are spaced apart by an integral number of cycles of metering by the meter. Thus the actual displacement of the piston is measured during an interval defined by the meter. The piston is retracted by a piston and cylinder arrangement 30,31. IMAGE