Comparison Between Reciprocating and Centrifugal Compressors

Comparison between reciprocating and centrifugal compressors can done in aspects like mechanical efficiency, cost, noise, pressure ratio, multi stage possibility, volume handled, maintenance required or not, weight of compressor, operation speed, isentropic efficiency, higher compression efficiency condition and suitable operation conditions.

S.no	Reciprocating Compressors	Centrifugal Compressors
1	Reciprocating compressors have poor mechanical efficiency due to large sliding parts.	Centrifugal compressors have better mechanical efficiency due to absence of sliding parts.
2	Installation cost for setting up reciprocating compressors is higher.	Installation cost for setting up centrifugal compressors is lower.
3	Reciprocating compressors produce greater noise and vibrations.	Centrifugal compressors have comparatively salient operation.
4	Pressure ratio up to 5 to 8.	Pressure ratio up to 4.
5	Higher pressure ratio up to 500 atmosphere is possible with multistage of compressor.	It is not suitable for multistage.
6	It runs intermittently and delivers pulsating air.	It runs continuously and delivers steady and pulsating free air.
7	Less amount of volume is handled.	Large amount of volume is handled.
8	More maintenance is required.	Less maintenance is required.
9	Weight of reciprocating compressor is more.	Less weight compared to other compressors.
10	Reciprocating compressor operates at low speed.	Centrifugal compressors operates at high speed.
11	Isothermal efficiency should be better.	Isentropic efficiency should be better.
12	Higher compression efficiency at pressure ratio more than 2.	Higher compression efficiency, if pressure ratio is less than 2.
13	Suitable for low discharge and high pressure ratio.	Suitable for high discharge and low pressure ratio.

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