3.4.13 Hose pump - Pumpfocus

Hose pump

A hose pump (or peristaltic pump) transports fluid by mechanically squeezing a space enclosed by a flexible element. The most usual hose pump operates by means of rollers or cams acting directly upon the hose containing the fluid, figure 3.46a. The number of rollers or cams vary depending upon the manufacturer, usually 2 or 3. A pump may be fitted with one or more hoses, sometimes as many as thirty. Peristaltic pumps are used in industries for slurries and mud with a high degree of fluid content and for aggressive chemicals or in laboratories for sterile applications and medical applications like heart lung machines.

Different hose options allow the pump to handle a large and wide range of fluids, the pump type can also be controlled for flow rates and pressures to suit almost every application. Maybe because of it´s ability in heavy duty slurry and sludge handling for process industries, users tend to forget the hose pumps as well as the peristaltic pump’s eminent suitability for handling shear sensitive products. The smooth, squeezing action makes it ideal to use with sensitive polymers, flocculants and fragile cell cultures.

Hose pump with three rollers — Figure 3.46a

Figure 3.46a Hose pump

In a hose pump the pumped fluid is completely enclosed and cannot leak, assuming that the hose does not fracture as a result of the mechanical stresses imposed. The lack of valves, seals and glands makes it look inexpensive to maintain and the hose being the only common replacement part on a peristaltic pump, a relatively low cost item that is easily exchanged. Its easy to think that maintenance cost can be neglected but be aware that a wrongly fit hose or one with bad quality wont lats long and maintenance cost might be higher than expected. Since such failures cannot be predicted it is necessary to replace with original hoses regularly as a preventive measure.

Hose pumps can be used for all types of fluids and to some extent even gases. The suction capacity varies greatly for different designs. Pressure increases between 0.1 and 0.3 MPa are normal. The capacities vary from small metering quantities of 0.001 l/h up to flows of 10-100 m³/h.