Question

Which of the following valves is used to maintain pressure in the system?

(a) Pressure relief valve

(b) Check valve

(c) Manual control valve with variable flow plug

(d) Pneumatic control valve with variable-flow plug

This question was posed to me in a job interview.

Asked question is from Pipes, Valves and Fittings in division Building Blocks of Dairy Processing of Dairy Engineering

Answer 1

Correct answer is (a) Pressure relief valve

To elaborate: A pressure relief valve maintains the pressure in the system. If the pressure is low, the spring holds the plug against the seat. When the pressure has reached a certain value, the force on the plug overcomes the spring force and the valve opens.