Pumps

Pumps are nearly the most common type of machine used in all industrial and domestic applications, second to electric motors. There are almost 10-12 different types of pumps used in a car assembly that contribute to various functions of the car. A large number of industrial processes would be unimaginable without pumps.

Technically, a pump is a unit used for transportation of liquids, fluids and gases through pipes or similar channels. The functionality of pumps is very simple, it consists of a suction mechanism at one end where the material is drawn in. Counter pressure is developed at the other end which forces the material out. Depending upon the operating mechanism, pumps can be broadly classified as piston pumps and centrifugal pumps. There is one type of pump that uses fluid energy to operate. These are called jet pumps.

Piston pumps – these have a reciprocating action, like a to-and-fro or up-and-down motion. These types of pumps deliver the fluid in a pulsating form. For example consider a to-and-fro piston pump. When the piston moves from its original position to the extreme position, the pressure inside the channel is dropped and a suction action takes place which causes the fluid from outside to rush inside. Similarly when the fluid is to be delivered, the piston is moved from its extreme position to the original position and the pressure difference forces the fluid out.

Some types of piston pumps are mentioned below:

• Lifting pumps - the piston has defined up-and-down motion.
• Diaphragm pumps – the piston in this case is a diaphragm, whose movement is controlled using an actuating rod.

Centrifugal pumps – these pumps produce a continuous steady outflow of fluids. The pressure required for the operation is created by the centrifugal acceleration of the impeller. The fluid flows axially towards the impeller, which deflects the fluid, causing a direction change. This change in direction causes acceleration, which increases the pressure at the outlet. The whole mechanism revolves around the principle of converting kinetic energy of the fluid into pressure energy.

Cars often use diaphragm pumps, which direct the gasoline from the tank to the fluid injection plugs. These pumps have fuel filters incorporated in them. Diaphragm pumps are quite universal and are available in several sizes. Waste water treatment plants, chemical plants, oil industry, food industry, public utilities, fire fighters, plumbing companies, irrigation firms, aerospace, aviation and transportation industries are some of the other domains that make use of different types of pumps.