32-differences between centrifugal pumps and reciprocating pumps

COMPARISON BETWEEN CENTRIFUGAL PUMPS & RECIPROCATING PUMPS

Sl No.

Centrifugal pump

Reciprocating pump

1

It is dynamic type pump

It is a positive displacement pump

2

It produces more flow

It produces lesser flow

3

It produces less head (pressure) for same size of pump

It produces more head (pressure) for the same size of pump

4

Work is done by rotating the impeller

Work is done by back & forth movement of piston or plunger or diaphragm

5

Simple construction

Complex construction

6

Simple operation

Complicated operation

7

Smoother operation no vibrations

Due to reciprocating movement vibrations are always there

8

Continuous supply of fluid

No continuous supply of fluid

9

Pressure increases by decreasing the flow

Flow is independent on pressure

10

High viscosity fluid cannot be pumped easily

High viscosity fluids can be p[umped very easily

11

Low viscosity fluids can be pumped very easily

Cannot be pumped very easily

12

Centrifugal pumps are low costlier

More costlier than centrifugal pumps

13

Maintenance is easy

Maintenance is difficult

14

Less maintenance cost

More maintenance cost as there are more rotating & moving parts in pump

15

Grease & oil lubricated

Most of the pumps are oil lubricated only

16

Cab ne installed easily

Complicated installation

17

Require less space for same size pump

Require more space for same size pump

18

Less accurate in flow measurement

More accurate for flow measurement

19

Not suitable for small quantity dosing system like chemical plants or water treatment plants

Best for small & accurate quantity dosage like in water treatment plants to maintain desired water parameters

20

Priming is required for centrifugal pumps

Priming is not required

21

Pumps can be started with discharge valve closed condition

Pumps cannot be started with discharge valve closed condition

22

In consists of impeller to create head & flow

In consists of plunger, pistons & diaphragms to create head & flow

23

Centrifugal pumps might be of positive as well as negative suction

Most of the reciprocating pumps are of positive suction

24

PRV is not required

PRV is required to protect the pump during discharge line blockage

25

Minimum recirculation system is there to protect pump at lower discharge flow

Recirculation line is not required as head is independent of flow

26

Pump major internal parts are impeller, wear ring, shaft sleeve, stuffing box, lantern ring, balance & counter balance disc  etc

Pump major internal parts are, connecting rod, crank, piston, plunger, diaphragm, gears etc

27

Reverse rotation of the pump affects pump performance & capacity

Reverse rotation of the pump does not affect much

28

Pipe lines have fittings like eccentric & concentric reducer

Eccentric & concentric reducers are not used

29

Generally air vessels are not used in reciprocating pumps

Air vessels are used in reciprocating pumps

30

Thrust balancing is required in high pressure centrifugal pumps

Thrust balancing is not required

31

Cavitation can damage pump internals & related piping system

Cavitation does not affect much

32

For same flow foundation required  is not much robust & strong

Strong & robust foundation is required


Reference books for power plant O&M



Reciprocating pumps

Reciprocating pumps parts























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