abogadie- single stage centrifugal pump.pptx

8/14/2019 Abogadie- Single Stage Centrifugal Pump.pptx

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Centrifugal Pump(Single Stage)

Nicolle Jan A. Abogadie

BSEE V-2


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Brief History The centrifugal pump was developed in Europe in the late 1600s and was seen in the

United States in the early 1800s. Its wide spread use, however, has occurred only in

the last seventy-five years. Prior to that time, the vast majority of pumpingapplications involved positive displacement pumps.

Source: http://www.pacificliquid.com/pumpintro.pdf

Year 1475According to Reti, a Brazilian soldier and historian of science, the firstmachine that could be characterized as a centrifugal pump was a mud lifting machinethat appeared in a treatise by the Italian Renaissance engineer Francesco di GiorgioMartini.

Year 1687French-born inventor Denis Papin develops the first true centrifugalpump, one with straight vanes used for local drainage.

Year 1851British inventor John Appold introduces the curved vane centrifugalpump.

Year 1851John Gwynne files his first centrifugal pump patent. His early pumpswere used primarily for land drainage, and many can still be seen today in pump

house museums. They were usually powered by Gwynnes' steam engines. By the endof the 19th century, Gwynne was producing pumps of all sizes to cover all industrialapplications, from small electric pumps to those rated at 1,000 tons per minute. Hiscompany had also begun to produce scientific pumps, e.g., porcelain pumps forchemical works. In the 1930s they were producing almost 1,000 different models.

Source: http://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-years
http://www.pacificliquid.com/pumpintro.pdfhttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pump-zone.com/topics/pumps/pumps/history-pumps-through-yearshttp://www.pacificliquid.com/pumpintro.pdfhttp://www.pacificliquid.com/pumpintro.pdf


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Operation: Centrifugal pumps move fluids by stirring them faster and

faster in a circular motion and then changing the increased

speed of the fluid into pressure. Depending on the design ofthe particular pump, centrifugal pumps are capable of either

very high or very low discharge pressures, or very high or very

low volume discharge.

Major parts

1. Pump Casing

2. Seal Chamber / Stuffing Box

3. Volutes and Diffusers

4. Impellers

5. Shaft Sleeves


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Pump casing Casing may be either solid or split. Solid casing implies a

design in which the discharge waterways leading to the

nozzle are all contained in one (1) casing, or fabricated

piece. It must have one (1) side open so that the impeller

may be installed into the casing. As the sidewalls

surrounding the impeller are in reality part of the casing,

a solid casing strictly speaking, cannot be used, designsnormally called solid casing are really radially split. Most

single stage end suction pumps are solid casing pumps.

A split casing pump is made of two (2) or more parts

fastened together and commonly referred to as ahorizontally split case pumps.


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Pump casing


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Seal Chamber / Stuffing Box

Seal Chamber and Stuffing box bot refer to a chamber, eitherintegral with or separate from pump case housing that formsthe region between the shaft and casing where sealing mediaare installed. When the sealing is achieved by means of amechanical seal (Figure 8), the chamber is commonly referredto as a Seal chamber. When the sealing is achieved by meansof packing, the chamber is referred to as a Stuffing box (Figure9). Both the seal chamber and the stuffing box have theprimary function of protecting the pump against leakage atpoint where the shaft passes out through the pump pressurecasing. When the pressure at the bottom of the chamber is

below atmospheric, it prevents air leakage into pump. Whenthe pressure is above atmospheric, the chambers preventliquid leakage out of the pump. The seal chamber and stuffingboxes are also provided with cooling or heating arrangementfor the proper temperature control.


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Volutes and Diffusers Volute and diffuser describes the area in which a centrifugal

pump converts the kinetic energy of the fluid into pressure

The volute pump derives its name from the spiral-shaped

casing surrounding the impeller and converts velocity energy into

pressure energy. A centrifugal pump volute increases in size from its

initial point until it encompasses the full 360 degrees around the

impeller and then flares out to the final discharge opening. The wall

dividing the initial section and discharge nozzle portion of the casingis called the tongue of the volute or the cut-water.

In a single stage volute pump that is operating at normal

capacities the forces on the impeller are balanced, at reduced flows

they are not. The amount of this force depends on pressures and

impeller size. This force can distort (bend) the shaft and the causerubbing of the impellers on the casing. If the condition persists, the

result is often a broken shaft. There are several ways to solve this

problem. One (1) is to use heavier shafts and bearings. Another way

is to use a double-volute (Figure 10), or a diffuser (Figure 11).


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Volutes and Diffusers

Diffuser (Figure 11) performs the same function as volutes,converting kinetic energy into pressure energy. It consists of anumber of vanes set around the impeller. These acts tofurther divide the forces to lessen the shaft bending. Diffusersare used mainly in high-pressure multistage pump designs andin vertical pumps.


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Impellers

The impeller is the main rotating part that provides the centrifugalacceleration to the fluid. They are often classified in many ways.

Based on major direction of flow in reference to the axis ofrotation

1. Radial flow 2. Axial flow

3. Mixed flow

Based on suction type

1. Single-suction

2. Double-suction

Based on mechanical construction

1. Closed

2. Open

3. Semi-open


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Shaft Sleeves

Shaft sleeves (Figure 21) are used on pumps to protect the

shaft from erosion and corrosion. Shaft sleeve are commonly

used as stuffing boxes leakage joints and bearings and, like

wear rings, provides a cheap an easy way to renew a shaft to

its original dimensions.


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Applications:

1. Energy and Oil- refineries, power plants

2. Building Services- pressure boosting, heating installations,fire protection sprinkler systems,

drainage, air conditioning

3. Industry and Water engineering- boiler feed applications,water supply (municipal,

industrial ), wastewater management, irrigation, sprinkling,drainage and flood protection.

4. The Chemical and Process Industries- paints, chemicals,

hydrocarbons, pharmaceuticals, cellulose, petro-chemicals,sugar refining, food and beverage production.

5. Secondary systems- coolant recirculation, condensatetransport, cryogenics, refrigerants

abogadie- single stage centrifugal pump.pptx

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