If the pressure in the suction line of the pump is less than the vapour pressure of the fluid, it results in the formation of bubbles and collapsing of those bubbles at the ‘eye of the impeller’ and that is termed as cavitation.
The pressure in the suction line can drop due to serval reasons.
● The suction line has too many turns and bends (avoid that, talk to layout and piping engineers)
● Plugged strainer or filter in the suction line (ensure the line is clean, maintenance is necessary)
● Rusted Pipe results in friction losses (keep an eye on those and change if necessary)
● Low level in the suction vessel (make sure that it operates at operating set point or close to it)
● Damaged fittings over a period and so forth