Centrifugal Pumps - A Deep Study (Part 3)

End suction Centrifugal and Split Case Piping Suction Conditions End suction and split case pumps can be installed in suction lift or suction headache conditions. The piping system associated with the pump varies slightly depending on the suction conditions. Since the suction lift condition is the most difficult, it is used in the following description. Suction Piping Most pumps in a suction lift condition require a foot valve on the end of the suction line to prevent the pump from losing prime. Most foot valves are large globe valves. The suction piping is usually designed one pipe size larger than the inlet of the pump with smooth piping material and fittings. Isolation valves on the suction side of a pump should only be gate or ball valves. Butterfly valves cause high headloss. As the piping reaches the pump, it is reduced to meet the pump connection using an eccentric reducer. The eccentric reducer prevents air accumulation in the piping.
Discharge Piping The discharge side of a p…

Centrifugal Pumps - A Deep Study (Part 2)

In the previous article we discussed briefly about the centrifugal pumps and its various configuraions. Now we are going to discuss a little deep about the various configurations explained in the previous article.
End Suction Centrifugal and Split Case ComponentShaft and BearingsThe shaft is used to transfer energy from the motor to the impeller.The most common shaft materials are carbon steel and stainless steel.Each shaft is supported by bearing that support loads along the shaft called thrust loads, and loads at right angles to the shaft. called radial loads.The bearings may or may not be a part of the motor. Impellers The energy is transfered from the shaft to the impeller and from the impeller to the water.There are 3 types of impellers, based on the number of shrouds: Closed Impeller - When an impeller has a shroud in the front and in the back.Semi-Open Impeller - When there is only a shroud in the back of the impellerOpen Impeller - When there is no shrouds. Wear Rings
With closed im…

Centrifugal Pumps - A Deep Study (Part 1)

Centrifugal pumps are a sub-class of dynamic axisymmetric work-absorbing turbo-machinery.Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow.
Centrifugal Pumps – Energy InputIf you were to cut a section out of the top of a pipe and use a canoe paddle to move the water, you would have a pump. It would not be very efficient, but you would be inputting energy into the water. If you reshaped the paddle into an impeller, you would be able to place more energy into the water. The energy would be transferred from the impeller to the water due to the friction between the impeller and the water. However, water would splash out onto the floor. This is because centrifugal forcecauses the water to fly outward away from the impeller.
The Pump Case
If you surrounded the impeller with a case, you could control the waterand obtain a more efficient energy transfer. The case that you would use is volute (spiral-shaped).…

Selection and Application of Pumps

The pumping system selection process needs to consider the properties of the fluid to be pumped, the pressure and flow requirements over time, and the environmental conditions. Pumping applications include constant and variable flow rate situations, where single or networked loads can be present. Pumping systems may also consist of open loop or closed loops where the fluid is fully or partially recirculated. The choice of pump can be significantly influenced by the inherent properties of fluid being pumped. The main considerations as discussed below include: Fluid PropertiesEnd Use Requirements andEnvironmental FactorsFluid Properties Acidity or Alkalinity (pH) and material chemical composition. As caustic and acidic fluids can degrade pumps through corrosion, the fluid chemistry must be considered when selecting pumps materials.Operating Temperature: - In cases where the pumped fluids may be hotter than 200 Father pump materials must be evaluated for expansion.…

Classification of Pumps

Pumps may be classified on the basis of the applications they serve, the materials from which they are constructed, the liquids they handle, and even their orientation in space. All such classifications, however, are limited in scope and tend to substantially overlap each other.A more basic system of classification,first defines the principle by which energy is added to the fluid, goes on to identify the means by which this principle is implemented, and finally delineates specific geometries commonly employed. This system is therefore related to the pump itself and is unrelated to any consideration external to the pump or even to the materials from which it may be constructed.
Under this system, all pumps may be divided into two major categories:
 (1) Kinetic/Rotodynamic,in which energy is continuously added to increase the fluid velocities within the machine to values greater than those occurring at the discharge so subsequent velocity reduction within or beyond the pump produces a …

The History of Pumps

The man has been using pumps of some type for 4000 years, which makes 50 years a very short time in the history of pumping. Indeed, looking back at the most significant developments in technology, the last fifty years seem relatively insignificant. By 1959, all the major pump designs had been introduced and mostly developed into commercial products. So what has World Pumps been writing about for the past 50 years?

The earliest pumps we know of are variously known, depending on which culture recorded their description, as Persian wheels, waterwheels, or norias. These devices were all undershot waterwheels containing buckets that filled with water when they were submerged in a stream and that automatically emptied into a collecting trough as they were carried to their highest point by the rotating wheel. Similar waterwheels have continued in existence in parts of the Orient even into the twentieth century.

The best-known of the early pumps, the Archimedean screw, also persists into modern…

Introduction to Pumps

Pump is the one of the first pieces of powered machinery to be invented at the dawn of the industrial age was a crude form of pump. The pump has since evolved into an endless variety of types, sizes, and applications. This blog will give an overview of the general types of pumps that are in common use in process plants. A functional understanding of pumps, their use, and application, is essential to understand how most processes are handled in process plants today.
Pump is a machine or mechanical equipment which is required to lift liquid from low level to high level or to flow liquid from low pressure area to high pressure area or as a booster in a piping network system.

The principle behind the working of pump is "Conversion of mechanical energy into fluid flow energy".

Pump also can be used in process operations that requires a high hydraulic pressure. This can be seen in heavy duty equipment’s. Often heavy duty equipment’s requires a high discharge pressure and a low suctio…