STH and STQ Ratio:Matic® Duplex pumpsSTH and STQ Ratio:Matic® Duplex pumps from Fluid Metering, Inc. are ideal for precision mixing, diluting, and proportional metering for OEM medical, analytical, and industrial instrumentation. The pumps are characterized by:

  • Ratio:Matic® pumps consist of two FMI valveless pump heads direct coupled to a single variable speed drive; a 23 frame stepper motor is standard,  although other drive types can be used.
  • The displacement of each pump head is independently adjustable, and a variety of pump head sizes can be used in combinations to achieve dispensing ratios from 1:1 up to 500:1.
  • Typically, each pump head is calibrated at the factory, locked in place, and will not require recalibration in the field, even after millions of cycles.
  • Models are also available that can be adjusted in the field for applications that require frequent changes in mixing ratios or dispense volumes.
  • The pumps feature FMI’s CeramPump® valveless piston pump technology — this unique pump design utilizes one moving part, a rotating and reciprocating ceramic piston to accomplish both pumping and valving functions without valves.
  • The piston and mated liner are made of dimensionally stable, sapphire-hard ceramics which ensure long term, drift-free accuracy of 1% or better for millions of maintenance-free cycles.