... composed of measuring unit, a pair of Roots rotor, transmission components and registry unit. It is of high accuracy, large flow ... operation, none pulsating flow, low noise, good reliability and is able to remote monitor with 4-20mA signal.Main ... : JB/T9242-1999 positive displacement flowmeterMarket service: flow metrology and custody transfer in oil, petrochemical, electric power, traffic, food ...