Do You Need to Move Corrosive Fluids? Try a Peristaltic Pump

If you need to move corrosive fluids, a peristaltic pump is the standard pump of choice. A peristaltic pump is named after its action, which resembles peristalsis, or the mechanism of swallowing food or liquids, present in most mammals and reptiles.Peristaltic Pump

It is classified as a positive displacement pump; its advantage for use with corrosive fluids is that the fluids go through a tube, thus removing any chance of cross-contamination with other components of the pump that may be exposed. The peristaltic action is caused when one end of the tube is pinched, thus compressing the tube, and moving the fluid away from the compressed part of the tube.

In addition, when the pressure is released from the part of the tube that has been pinched, it draws fluids from the other end into the space that was just created. Usually, two or more rollers are used to initiate the pinching action; the rollers are attached to a rotor which is responsible for fluid movement.

Currently, we carry the Verderflex Dura series and the VF series, also from Verderflex. The Dura series is generally accepted as the first authentic advance in hose pump technology since the advent of the high pressure hose. It combines the compact size of a close-coupled pump with the performance of a traditional long coupled pump.

The Dura 10 has a maximum flow of 130 l/h, a maximum pressure of 12 bars, and a 0.55 kW motor. The Dura 15 has a maximum flow of 424 l/h, a maximum pressure of 12 bars, and a 0.92 kW motor. The Dura 25 has a maximum flow of 1190 l/h, a maximum pressure of 12 bars, and a 1.5 kW motor. The Dura 35 has a maximum flow of 5488 l/h, a maximum pressure of 12 bars, and a 3.0 kW motor.

The VF series is the original peristaltic hose pump from Verderflex. The VF 125 is currently the largest hose pump in the world. The smallest model: the VF 10, which has a maximum flow of his 0.18 m3/h, maximum pressure of 7.5/12 bars, and a 0.18 kW motor. The aforementioned VF 125 has a maximum flow of 90 m3/h, maximum pressure of 15 bars, and a 35 kW motor.

For more information on our peristaltic pumps, call us at 1300 922 973 or go to our contact page.

How a Peristaltic Pump Works

If “peristaltic pump” reminds you vaguely of school, it’s because you might have heard it in a high school biology class. Peristalsis is the process by which food gets from your mouth to the other end of your gastro-intestinal tract. A more visible example might be seeing time-lapse photography of a snake swallowing an object that is wider than he is.

In peristalsis, whatever is being moved is on the inside of a tube, and outside forces are squeezing the tube, starting at one end and moving to the other end. As it is in nature, so it is with a peristaltic pump.

A peristaltic pump is classified as a positive displacement pump, and is used to pump fluids. The tube is filled with product, and a rotor with rollers, “wipers” or “shoes,” turns, causing the rollers to compress the tube at one end. Just like the biological example we used, the fluid is forced to the other end and finally out of the tube. Similar to squeezing a tube of toothpaste.

When the fluid is displaced, it causes a vacuum, and product is drawn in behind the rollers to refill the tube. This is often called “resilience” or “restitution.” The cycle starts over again for as long as there is fluid to pump and the rotor turns.

A popular application for a peristaltic pump is when sanitation is at a premium. Because neither the rotor nor the rollers touches the inside of the tube, there is less chance of any outside parts cross-contaminating the contents of the tube. Medical applications include pumping IV fluids and circulating blood through a heart-lung machine during heart bypass surgery.

It is also used for aggressive chemicals and other instances where the environment needs to be protected from the fluids, or where the fluid or sludge needs to be protected from the environment.   Due to their design, they are often the first choice for pumping viscous fluids or abrasives.

This means that there are no pressurised seals or O-rings to worry about. The only major design concern is that the tubing has to be elastomeric to maintain the integrity of the circular cross sections after repeated and prolonged use.

Besides being difficult to contaminate, peristaltic pumps are also extremely low-maintenance, and no backflow or check valve is needed to prevent siphoning.