CENTRIFUGAL PUMP

Working Principle of Reciprocating Pump

PRINCIPLE: Reciprocating pump operates on the principle of pushing of liquid by a piston that executes a reciprocating motion in a closed fitting cylinder.

DIAGRAM:

CONTRUCTION DETAILS OF A RECIPROCATIN PUMP:

Components of reciprocating pumps:-

a) Piston or plunger: – a piston or plunger that reciprocates in a closely fitted cylinder.

b) Crank and Connecting rod: – crank and connecting rod mechanism operated by a power source. Power source gives rotary motion to crank. With the help of connecting rod we translate reciprocating motion to piston in the cylinder.

c) Suction pipe: – one end of suction pipe remains dip in the liquid and other end attached to the inlet of the cylinder.

d) Delivery pipe: – one end of delivery pipe attached with delivery part and other end at discharge point.

e) Suction and Delivery value: – suction and delivery values are provided at the suction end and delivery end respectively. These values are non-return values.

WORKING OF RECIPROCATING PUMP

Operation of reciprocating motion is done by the power source (i.e. electric motor or i.c engine, etc). Power source gives rotary motion to crank; with the help of connecting rod we translate reciprocating motion to piston in the cylinder (i.e. intermediate link between connecting rod and piston). When crank moves from inner dead centre to outer dead centre vacuum will create in the cylinder. When piston moves outer dead centre to inner dead centre and piston force the water at outlet or delivery value.

EXPRESSION FOR DISCHARGE OF THE PUMP:-

Where: –

Q: – discharge in m3/sec

A: – cross-section of piston or cylinder in m2

L: – length of stroke in meter

N: – speed of crank in r.p.m