The Centrifugal Pump

A centrifugal pump is a gadget used for moving gases and liquids. It has two main parts: the impeller and the circular pump casing around it.

The volute centrifugal pump is the most common of this type of pump. Fluid enters the pump at high speed near the center of the rotating impeller and hurled against the casing by the vanes. The centrifugal pressure forces fluid or water through a hole in the casing. This opening progressively enlarges in a spiral motion, which minimizes the speed of the fluid and thereby raising its pressure.

Centrifugal pumps produce a constant flow of fluid. It functions by turning kinetic energy into potential energy and measured as static fluid pressure (SFP) at the outlet of the pump. This action is defined by Bernoulli's principle.

With the mechanical rotation of an electric motor, the pump’s impeller rotation provides kinetic energy to the fluid through the centrifugal force. The fluid is taken from the hole piping and through the impeller intake that is forced outwards through the impeller vanes all the way to the outlet piping. The impeller is the rotating part that converts energy into kinetic energy while the volute or diffuser is the stationary device that turns kinetic energy into pressure energy.

As the fluid comes out of the impeller vane (if the outlet piping is too high to let air flow), the kinetic fluid force is converted into static pressure. If the outlet piping is wide open at a lower level, the fluid will be released at faster and greater volumes.

The typical areas of application for centrifugal pumps are: industrial effluent treatment, transfer of 'live' fish, mine drainage, feeding oily water separators, sump emptying, oil and chemical spillages, processing of waste oils and sludge, parts washer equipment, municipal wastewater treatment, plants transfer of fruit and vegetables, etc.

 

Cantilever pumps are also referred to as vertical centrifugal pumps. They use a unique shaft and bearing foundation design that lets the volute to be suspended in the sump while the bearings are outside. This pump feature uses no box stuffing to seal the shaft but instead has a "throttle bushing". A common application for this style of pump is in a parts washer.

The centrifugal pump is one of the simplest types of equipment in liquid/water pumping processes. It is crafted to convert energy into velocity or kinetic energy and then into liquid pressure energy that is being pumped.

The energy changes occur by virtue of two main parts of the pump, the impeller and the volute or diffuser. The impeller is the rotating part that converts driver energy into the kinetic energy. The volute or diffuser is the stationary part that converts the kinetic energy into pressure energy.