S Series Metering Pumps Performance Benefits

Electronic solenoid/diaphragm pumps that provide economical and eco-friendly chemical injection



The IChemE Awards recognize innovation and excellence in making outstanding contributions to safety, the environment, and sustainable development in the chemical and bioprocess industries.

Hydra-Cell S Series electronic metering pumps are an economical and environmentally-friendly choice for reliable chemical injection in metering applications.

They are ideal for low-flow, low-pressure requirements and will complement other Hydra-Cell Seal-less Pumps and Hydra-Cell Metering Solutions pumps in many different types of installations.

SM manual control units as well as SP/ST/SA pulse/analog control models offer up to 300 strokes per minute. Maximum flow rates range from up to 25 ml/min (0.40 gph / 1.5 lph) to 220 ml/min (3.49 gph /13.2 lph) depending on model.

Several materials of construction choices and various design options result in pumps ideal for specific applications including chemical injection, high-pressure boiler, high-viscosity fluids, outgassing fluids and more.


Versatile, Economical and Easy to Operate

  • Manual-control SM models feature a simple hand-operated dial with stroke adjustment in 3% increments up to 300 strokes per minute.
  • SP, ST & SA models have pulse-in (SP), pulse-in with timer (ST) or pulse-in/analog-in (SA) control and stroke adjustment in 1-stroke increments up to 300 strokes per minute.
  • SP, ST & SA models also feature simple key operations and intuitive user interface - a bright, sharp LED display is clearly visible in lowlight as well as high-glare areas.
  • “Eco-friendly” environmentally sound operation is standard with SP, ST & SA models - this feature can lower power consumption up to 55%.
  • Double-ball check valve ensures accurate metering and reduces the chance of water hammer.
  • PVC, PVDF, 316SS, and Acrylic liquid end component choices to match specific applications
  • Model available with a pump head that can be moved in three directions to provide flexibility of installation
  • Waterproof (IP65), dust-resistant structure ideal for indoor or outdoor use
  • Pump housing is molded from high-impact PPO, an engineered thermoplastic that provides dimensional stability and excellent resistance to heat
  • Power supply range for operation between AC100 and 240V (±10%) with plugs available for North America, Europe, UK, and Asia
  • Fast, easy maintenance as liquid-end parts can be disassembled and replaced by simply detaching four bolts

Safety Mechanisms to Handle Air Build-up

S Series pumps feature an innovate design to minimize dead space and prevent air entry and build-up inside the pump. In case air or another gas does enter the pump and impede chemicals from being discharged, each S Series model has an easy-to-use mechanism to remove the air or gas.

Manual Air Release Valve

Air Release Knob
Air Release Port

S Series models 030, 060, and 100 feature a manual air release valve with a knob that is turned counterclockwise then clockwise.

Manual Air Release Valve with Integral Relief Valve Option

Air Release with Relief Valve Knob
Air Release Port

S Series pump models 03R, 06R, and 10R are equipped with an integral air release valve and external knob that is always turned clockwise.

Air Release for Stainless Steel Models

Air Release Nozzle
Hose Pump

S Series Stainless Steel models (ST type pump heads) feature an air release nozzle with a hose pump that is attached for purging air.

Safety Mechanisms to Prevent Air Lock (Outgassing)

  • Outgassing results when the fluid pressure drops below the saturation pressure of a gas dissolved in a liquid. If this occurs, gas comes out of the solution and builds up inside the pump. When air enters the pump head, it prevents the chemicals from being discharged.
  • S Series pumps for outgassing fluids (e.g. Sodium Hypochlorite) with Acrylic pump heads feature an innovative design to minimize dead space and prevent air entry and build-up in the pump.
  • If air enters the pump, or if outgassing occurs, safety mechanism with combat air lock and outgassing. The transparent Acrylic liquid ends allow the operator to see whether air is present in the pump head.

Air Release Port
Chemical Discharge Port

SM (manual) models with Acrylic pump heads discharge entrapped gas from the air release port. Gas or bubbles from the chemical tank are suctioned through the air release joint and expelled.

Automatic Degassing Joint

Select SP/ST/SA models with Acrylic pump heads feature a degassing joint that eliminates virtually all causes of air entrapment. Air is purged without infiltration of the pump head and goes out through discharge piping.

  • “If the owner of a plant wants cost- effective pumps... he will buy pumps with the lowest Life Cycle Cost. Hydra-Cell is simple in construction, less elaborate in design and physically smaller for equivalent flow/pressure performance. These differences can substantially affect both purchase and operating costs.”
    Dr. Ing Friedrich Wilhelm Hennecke, Chemical Engineering World



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