Peristaltic pump
A peristaltic pump moves medium by squeezing a flexible hose or tube against a curved track with rollers or shoes. The medium touches nothing but the bore of the hose, so the pump has no seals, valves or moving parts in the wetted path.
In more detail
It is a positive displacement pump, so it sweeps a fixed volume per revolution and its flow follows shaft speed rather than discharge pressure. That makes it self-priming and repeatable enough to meter with, and it runs dry without losing a mechanical seal, because it has no mechanical seal to lose. The hose is the wear part. For the mechanism itself, see how a peristaltic pump works.
The duties it suits
Abrasive media point towards a peristaltic, because the slurry only ever runs through a rubber bore and there are no close clearances for grit to wear open. So do shear-sensitive media, because the medium is carried rather than accelerated. So does anything that would attack a mechanical seal, or that must not pick up anything from the pump.
Abrasive and shear-sensitive media both want pumping slowly, and that constraint appears nowhere on a performance curve. It is a selection decision taken before anyone reads a duty point off a chart.
Where it stops
The hose is a consumable. It flexes under every revolution and eventually fails, so replacement is a planned running cost and the pump has to be sited where you can get at it. Which compound you run changes how often, and that is covered on the peristaltic pump hose page.
Discrete rollers also give a pulsed flow rather than a smooth one, and the hose sets the pressure ceiling rather than the drive. A duty a rotary lobe or a progressive cavity pump takes comfortably can sit outside the range of a peristaltic passing the same flow.
Where a peristaltic sits against the other types we carry
We supply peristaltic pumps, so this is a live choice rather than a referral. The peristaltic range sits alongside rotary lobe and progressive cavity pumps, and all three overlap on abrasive, viscous and shear-sensitive work.
Take a peristaltic when the medium would attack a seal or wear a clearance open. Take a progressive cavity pump when the product is thick and has to move at a steady rate. Take a rotary lobe when the head has to strip down and clean in place. The honest limit is pressure: on the Crane ELRO range the mobile pumps stop at 1.5 to 2 bar and the stationary IP and XP pumps reach 13 bar.
Frequently asked
What is a peristaltic pump used for?
Peristaltic pumps handle abrasive slurries, shear-sensitive product, and metering and dosing duties where the flow has to be repeatable. They also suit a medium that would attack a mechanical seal, because the medium touches only the bore of the hose and there is no seal in the wetted path.
What is the difference between a hose pump and a tube pump?
Both are peristaltic. A hose pump squeezes a thick reinforced hose with shoes or rollers and covers industrial flows and pressures. A tube pump squeezes thinner, more flexible tubing with rollers and suits low-flow dosing and laboratory work. Manufacturers use the two names for the two ends of the same principle.
Is a peristaltic pump self-priming?
Yes. The hose recovering its shape behind each roller is what creates the suction, so the pump pulls air out of the suction line and primes itself. Crane rates the ELRO range at 9.5 m of dry suction lift.
Should you use a peristaltic or an air-operated diaphragm pump?
Air-operated diaphragm pumps earn their place in a narrower set of cases than their popularity suggests, mainly where there is compressed air on site and no electricity. Compressed air is expensive to produce, so the running cost is far higher than an electric drive, and the air supply's reliability and cleanliness become part of your pump. Where electricity is available, we would go electric.
Does Channel Pumps supply peristaltic pumps?
Yes. We supply the Crane ELRO range, mobile and stationary, from 15 mm hose bore up to pressure bands of 13 bar. Send us the flow, the pressure and the medium and we will size the pump and the hose compound together.