Peristaltic Pump Used for Pumping a Variety of Fluids

A peristaltic pump, or roller pump, is a type of positive displacement pump used for pumping a variety of fluids. The fluid is contained within a flexible tube fitted inside a circular pump casing (though linear peristaltic pumps have been made). A rotor with a number of "rollers", "shoes" or "wipers" attached to the external circumference compresses the flexible tube. As the rotor turns, the part of tube under compression closes (or "occludes") thus forcing the fluid to be pumped to move through the tube. Additionally, as the tube opens to its natural state after the passing of the cam ("restitution" or "resilience") fluid flow is induced to the pump. This process is called peristalsis and used in many biological systems such as the gastrointestinal tract. Applications Peristaltic pumps are typically used to pump clean/sterile or aggressive fluids because cross contamination with exposed pump components cannot occur. Some common applications include pumping IV fluids through an infusion device, aggressive chemicals, high solids slurries and other materials where isolation of the product from the environment, and the environment from the product, are critical. It is also used in heart-lung machines to circulate blood during a bypass surgery as the pump does not cause significant hemolysis. Peristaltic pumps are also used in a wide variety of industrial applications. Their unique design makes them especially suited to pumping abrasives and viscous fluids. Advantages No contamination. Because the only part of the pump in contact with the fluid being pumped is the interior of the tube, it is easy to sterilize and clean the inside surfaces of the pump. Low maintenance needs. Their lack of valves, seals and glands makes them comparatively inexpensive to maintain. They are able to handle slurries, viscous, shear-sensitive and aggressive fluids. Pump design prevents backflow and syphoning without valves. Source: wikipedia