Bellows Pumps
Bellows pumps (diaphragm pumps) from GRI are designed specifically for precise dosing applications at low pressures. A flexible bellows made from chemically inert material delivers the medium dry-run safe and without a dynamic seal. Up to 4 independently adjustable modules can be combined on a single motor.
Precision and Reliability for Demanding Applications
Bellows pumps, also known as diaphragm pumps, are found in numerous industrial sectors. Their design is based on a flexible bellows that ensures precise and reliable delivery of a wide variety of media. GRI bellows pumps are based on a special, proprietary polypropylene compound, resulting in a reliable and economical dosing pump with a long service life.
Operating Principle
The motor rotation is converted into a linear up-and-down movement by a crank drive; the stroke of the crank drive is adjustable. The bellows – typically made from PTFE or special polypropylene compounds – is continuously compressed and released. As it expands, a vacuum is created that draws in the medium; as it compresses, the medium is discharged in a controlled manner via valves. The delivery volume is determined by stroke length and stroke frequency. Up to 4 bellows modules can be driven by a single motor, enabling up to 4 different media to be delivered simultaneously – each module individually adjustable.
Fields of Application
- Chemical industry: dosing of acids, alkalis, solvents and other aggressive media
- Printing industry: delivery of inks and colourants within printing machines
- Pharmaceutical industry: delivery of high-purity media and suspensions
- Food industry: dosing of flavourings, colourings and other additives
- Analysis & laboratory: dosing of samples in analytical instruments
Bellows Pumps as OEM Components
As OEM components, bellows pumps are integrated into numerous industrial systems – for example into dosing systems for liquids and pastes, analytical systems for sampling, cleaning systems for detergents or packaging machines for filling containers.
- High precision through speed-controlled stroke regulation
- Chemically resistant to a wide range of aggressive media
- Dry-run safe thanks to the self-sealing bellows
- Gentle delivery without shear stress on the medium
- Modular design: up to 4 independent modules on one motor
- Compact design, ideal for OEM integration
Frequently Asked Questions about Bellows Pumps
What are bellows pumps particularly suited to?
Precise dosing tasks at low pressures – such as the exact metering of chemicals, flavourings or colourings.
Can several media be delivered at the same time?
Yes, up to 4 bellows modules can be operated independently of one another on a single motor, allowing 4 different media to be delivered simultaneously.
Are bellows pumps dry-run safe?
Yes. As the bellows seals itself and there is no dynamic seal, the pumps are dry-run safe.