GRI Bellows Metering Pumps
SubCategory: MeteringPumps
Manufacturer: GormanRuppIndustries
Industry: Agriculture;Aviation;BuildingServices;Ceramics;Chemical;FishFarming;HeatingWaterSanitation;ResearchDevelopment;SurfaceFinishing;WaterTreatment;PlasticsProduction;AdhesivesProduction;DetergentProduction;FertilizerProduction;PaintResinProduction;DyePigmentProduction;EmulsionProduction
Key specifications
- Flows up to 3000 ml/min
- Pressure up to 3.45
Product features
- Positive-displacement bellows principle → Provides controlled liquid displacement for metering duties.
- Flow range 3.9–3,000 ml/min → Supports selection across low-flow and higher-output dosing applications.
- Discharge pressure range 5–50 psi → Enables configuration to match the pressure requirement of the dosing point.
- Fluid temperature up to 60 °C → Supports a defined operating window for warmer process liquids.
- Viscosity capability up to 5,000 cSt → Extends use beyond water-like liquids when valve selection is appropriate.
- Polypropylene bellows and connectors → Provide a chemically resistant base construction for many fluids.
- Multiple O-ring and valve elastomers → Helps match wetted materials to corrosive and non-corrosive media.
- Poppet valves prevent backflow → Supports stable metering and helps maintain prime.
- Optional anti-siphon spring → Helps prevent unintended flow when positive suction head is present.
- Adjustable stroke and configuration → Allows output to be matched to the required dosing duty.
GRI Bellows Metering Pumps are intended for low-pressure metering duties where controlled liquid delivery and chemical compatibility are important. Typical applications include film and X-ray processors, silver recovery, semiconductor washing equipment, detergent dispensing, analytical equipment, floor scrubbers and water or wastewater treatment systems. For users, the main selection questions are required flow, discharge pressure, fluid temperature, viscosity and material compatibility.
The pumps use a positive-displacement bellows principle. Motor rotation is converted through a lever-pivot crank into repeated compression and expansion of the bellows module, moving liquid through the valve body. Poppet valves limit backflow, while optional springs can provide positive shutoff to reduce siphoning when positive suction head is present. GRI specifies polypropylene bellows and connectors with a choice of valve and O-ring elastomers for corrosive and non-corrosive fluids.
Verified manufacturer data lists flow from 3.9 to 3,000 ml/min depending on configuration, discharge pressure from 5 to 50 psi depending on bellows size, and fluid temperature up to 60 °C. Maximum stated viscosity is 5,000 cSt, and stroke-to-stroke accuracy is ±0.5% when the pump is set between 50% and 100% of full stroke.
For lifecycle planning, the modular bellows and valve arrangement allows operating parameters and material choices to be matched to the application rather than relying on a single configuration. Correct selection of bellows size, elastomers, suction conditions and anti-siphon measures helps reduce dosing errors and avoid unnecessary maintenance. AxFlow can support product selection, availability and replacement planning for the required GRI configuration.
