Check out our 3D animation of how FMI Valveless Metering Pumps work.


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.

Easy Flow Rate Adjustment

  • Moving the pump head position changes the piston stroke length and, in turn, the flow rate
  • Infinite fine flow adjustments between 0-100% flow rate
  • Flow rate indicator provides for accurate and simple linear calibration
  • Flow rate can be changed while pump is operating or at rest

Q Pump Adjustment

Pump Flow rate Adjustment

Adjustments are made by turning the Flow Control Knob which moves the flow rate indicator along a fixed 20 unit scale linearly calibrated "10-0-10". The "10" equals 100% flow rate in that direction, "0" equals zero flow. To improve the fine adjustment of the flow rates on Q pumps, there is an optional Dial Indicator Kit Q485 which provides for 1000 discrete settings.

RH Pump Adjustment

RH Pump Adjustment RH Pump Adjustment

Adjusting line flow on an RH model pump is accomplished by turning an easy-grip Flow Control Ring graduated in 450 divisions from 0 to 100% flow.