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Question: What is the diffrence between reciprocating pumps and centrifugal pumps?

(Posted by: sravanti on 2007-12-18 05:22:34)

Posted by: Andrew G on 2007-12-18, 05:26:09

Reciprocating = back and forth, i.e. piston Centrifugal = in a circular motion i.e. impeller

Posted by: BABUCHA on 2007-12-18, 05:29:33

Reciprocating pumps uses to and fro movement of piston and centrifugal pumps uses circular motion of fluid or it gives circular motion so as to make it move.

Posted by: AL in Bama on 2007-12-18, 05:31:28

Both answers above are correct. Additionally, reciprocating pumps, also known as 'positive displacement' can be designed for extremely high pressures, whereas centrifugal pumps only go up to a certain pressure and then 'dead-head' (develop no further pressure).

Posted by: buckhomes on 2007-12-18, 05:31:50

Reciprocating pumps move in a linear direction....typically up and down. A good example wold be a piston. Centrifugal move in a circle....and typically involve fluids however not always.

Posted by: johnathanapples on 2007-12-18, 05:38:17

Do you have a DICTIONARY? Can you look up RECIPROCATING and CENTRIFUGAL?...

Posted by: Marc Robertson on 2007-12-18, 06:12:55

A reciprocating pump is a piston that is moved by a turning shaft that reciprocates the piston back and forth in a cylinder. As the piston moves back, the inlet valve opens and allows fluid to enter the cylinder. When the piston stops, the intake valve closes and the outlet valve opens. Then the piston forces the fluid out the outlet valve. When the piston stops at the opposite end of travel, the outlet valve closes and the inlet valve opens and the cycle continues. The reciprocating, or piston pump is a positive displacement pump. This means that it will move a specific volume of fluid for each cycles unless something breaks or pump stalls the prime mover (as in a motor, engine.or some other motive power) This also means that a relief valve is required else the system can restricted and cause a pressure spike. This can easily blow something out do to excessive pressure. A piston or reciprocating pump is limited in pressure by it's mechanical ability to withstand pressure. Good piston pumps can handle 5,000 PSI/ 345 bar/ 34.5 MPa fairly easily. The downside is they don't handle dirty fluids well. A centrifugal pump is basically an impeller that rotates the fluid. The centrifugal force on the fluid pull the fluid out and builds the pressure on the outside of the impeller blades. The inlet is placed in the center of the impeller and the outlet collects around the outside of the impeller. These are not positive displacement pumps and are limited to a certain pressure. As the pressure increases on the outlet side, the fluid will backfeed through the impellers. They typically have an upper limit of 100-300 PSI max. This is done either by scaling the size of the pump up to get more centrifugal pressure or by putting several pumps in series. For example a car's fuel pump has muiltiple stages of centrifugal pumps in series intermally. The advantage is that they can handle dirty water as long as it doesn't clog up the inlet or impeller.

Posted by: AALUNGA on 2007-12-18, 06:57:32

Centrifugal Pumps (Roto-dynamic pumps) The centrifugal or roto-dynamic pump produce a head and a flow by increasing the velocity of the liquid through the machine with the help of a rotating vane impeller. Centrifugal pumps include radial, axial and mixed flow units. Reciprocating pumps operates by alternating of filling a cavity and then displacing a given volume of liquid. The positive displacement pump delivers a constant volume of liquid for each cycle against varying discharge pressure or head.

Posted by: Abdul A on 2007-12-18, 07:54:32

Reciprocating pump is a positive displacement pump.