Pump Selection 75,51,74-1.pptx

Engineering stuff

1. Presented By Hriday Biswas ( 51 ) Shubham Nath ( 75 ) Prasun Bairagi ( 74 ) B.P.C.I.T BRANCH :- ELECTRICAL Selection of Pump

2. What Is Pump ? A pump is a device that moves fluids (liquids or gases), or sometimes slurries. By mechanical action, typically converted from electrical energy into hydraulic energy. Pumps can be classified into three major groups according to the method they use to move the fluid:  direct lift ,  displacement , and  gravity  pumps.

3. Mechanical pumps serve in a wide range of applications such as: 1- Pumping water from wells, aquarium filtering, pond filtering, and aeration, 2- In the car industry for water-cooling and fuel injection, 3- In the energy industry for pumping oil and natural gas or for operating cooling towers and other components of heating, ventilation and air conditioning systems. 4- Dewatering in flood 5- Water supply in houses Application Of Pump -

4. Classification Of Pump

5. Piston Pump - 1.transmission of fluids or gases under pressure. 2.Power consumption is low. 3.Ensure maximum safety.

6. Plunger pump - 1.Have high efficiency. 2.Capable of developing very high pressures. 3.Low and easy maintenance

7. Diaphragm Pump- When the volume of a chamber of either type of pump is increased (the diaphragm moving up), the pressure decreases, and fluid is drawn into the chamber. When the chamber pressure later increases from decreased volume (the diaphragm moving down), the fluid previously drawn in is forced out. Finally, the diaphragm moving up once again draws fluid into the chamber, completing the cycle.

8. Centrifugal Pump- Liquid forced into impeller Vanes pass kinetic energy to liquid and liquid rotates and leaves impeller Volute casing converts kinetic energy into pressure energy

9. Total Suction Head: The static head, sometimes referred to as the pressure head, is a term primarily used in Hydraulics to denote the static pressure in a pipe, channel, or duct flow. It has the physical dimensions of length (hence the term “head”) and represents the flow-work per unit weight of fluid. In practice the static head is equivalent to the vertical distance from a given streamtube to the piezometric head line or the hydraulic gradient line. If P is the pressure in a streamtube, the static head is defined by P/ρg. Using this definition it is apparent that in a open channel flow, where the pressure is assumed to be hydrostatic, the static head is the distance from the streamtube to the water surface.

10. Major Items to be considered for pump selection Pump selection: Based on the fluid characteristics, turn-down ratio, discharge pressure and system requirements, availability of space, lay-out, energy and pump costs, code requirements, and the materials used in the construction.

11. The BHP required to drive a pump at a specific duty point is: *When gpm = Gallon Per Minute Sp.Gv . = Specific Gravity

12. HP = 4.64 GPM = 400 Head= 30 SGW = 1 EOM= 0.70

13. Net positive suction head : NPSH is defined as the combination of atmospheric pressure and static suction head that causes liquid to flow thru the suction piping and finally enter the eye of the impeller. The NPSH increases with flow due to pump internal losses like friction. NPSH can be divided into : NPSHR – required by pump at duty point, found on the pump performance curve. NPSHA – Available in the system and must be determined by calculation. * NPSHA > NPSH

14. PA = atmospheric pressure or pressure in tank ( psia ); PV = vapor pressure of liquid at maximum pumping temperature; Sp. Gr. = specific gravity at pumping temperature; HE = elevation head (ft); and HF = friction loss in suction line (ft). Refer to following pages for example calculations. Values for vapor pressure (PV ) and atmospheric pressure (PA ) found in pump handbooks. (see attached)

15. Affinity Laws : The affinity laws express the mathematical relationships between the several variables involved in pump performance. Q1 = capacity H1 = Head (feet) N1 – rpm Q2 = capacity H2 = Head (feet) N2 – rpm

16. References en.wikipedia.org www.Google.com

17. To All