The Vacuum Pump

Pumps, in whatever shape, size, or color they come, are something that most of us give particular importance to, yet they play a very important role in our daily life. These things normally catch our attention and we often don’t have to be so concerned with them. However, it is also important to know a little about the things that make our everyday existence a little bit easier.

It is just a water pump, yes. But have you ever thought about what these things can do when you are faced with problems at home? What do you do when there’s no one else around to help you get rid of the flood in your basement? Or, how do you fix that clog in your sink, or toilet? This is when you realize you need that vacuum pump to help you solve those miseries.

A vacuum pump is by no means a new design concept. Various pumps for water and gases that have come and gone with varying success have been in use for hundreds of years. An early predecessor to the vacuum pump came in the form of suction pump. This was invented by Arab engineer way back in the 12^th century.

The first prototype of the vacuum pump was conceptualized during the 15^th century. This design reached Europe in the form of the six-cylinder Monobloc device which could create a partial vacuum via a series of weights and pistons. This paved the way for newer vacuum designs during the early days.

The idea of the first vacuum pump did not instantly become such a hit. It took several years more for the device to convince people that it is in fact a great equipment to tackle water problems.

Vacuum pumps proved to be ideal by the 17^th century but the concept was not understood and it took a bunch of scientists, inventors and engineers to grasp the vacuum process and how it could solve the previous problems of not being able to pump water above a certain height.  Gaspar Berti, Evangelista Torricelli and Galileo played very crucial roles in the development of the vacuum pump technology.

The first real vacuum pump was manufactured in 1654 by Otto von Guericke. He conducted an experiment to prove that if the air was taken from a whole then there was no amount of force that could divide or separate the two halves of that whole.

This seemed to convince the early engineers. A few more tests were performed until 1855 when Heinrich Geissler took vacuum pumps to a new level using the mercury displacement pump method.

There are now three types of vacuum pump: the positive displacement pump (best for low vacuum needs); the momentum transfer pump (otherwise known as molecular pump, one of the most common vacuum pumps in use today); and the entrapment pump (best used for ultra-high vacuum tasks).

These pumps can be used in medical processes, ophthalmic applications, glass coating, analytical instruments, electric lamps production, freeze-drying and even sewage applications.

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.