FMI Patented "No-Valve" Technology The valveless pumping function is accomplished by the synchronous rotation and reciprocation of the ceramic piston in the precisely mated ceramic cylinder liner. One complete piston revolution is required for each suction/discharge cycle. Moving the pump-head position changes the stroke length and in turn the flow rate. Flow rate indicator provides for simple and accurate flow rate adjustment The Valveless Piston Advantage No valves to clog, hang up or service One moving part Drift Free Accuracy - better than 1% Precision Dispensing - CV's better than 0.17% Instant reversibility Inert ceramic & fluorocarbon fluid path Viscosity independent Positive displacement up to 6.9 bar (100 psig) Self-priming to 4.5 m (15 feet) FMI Pump Operation The piston rotates and reciprocates. As the piston is pulled back and the piston flat opens to the inlet port, suction is created and fluid fills the pump chamber. The inlet port is then sealed and crossover occurs. As the inlet port is sealed and the pump chamber is full, the outlet port opens up. Only one port is open at any time and at no time are both ports interconnected. The piston is forced down and the piston flat opens to the outlet port. Discharge is created and fluid is pumped out. The piston bottoms for maximum bubble clearing. The outlet port is sealed and the pump chamber is empty, the inlet port opens to start another suction stroke.   Overview piston pumps

Last modified 05/03/09