Question 49General Subjects - QMED

70% to pass

Which one of the following is a difference between a typical relief valve and a typical safety valve?

AThe actuator closing spring on a relief valve is in a compressed state whereas the actuator closing spring on a safety valve acts in tension.

BRelief valves are capable of being gagged whereas safety valves are not.

CA relief valve gradually opens as pressure increases above set point pressure whereas a safety valve fully opens at the set point pressure.

DThe blow down of a relief valve is greater than the blow down of a safety valve.

AI Explanation

The correct answer is C. A relief valve gradually opens as pressure increases above set point pressure, whereas a safety valve fully opens at the set point pressure. This is because the key difference between a relief valve and a safety valve is their response to pressure. A relief valve is designed to gradually open as the pressure increases above the set point, allowing a controlled release of pressure. In contrast, a safety valve is designed to fully open at the set point pressure, providing a rapid and complete pressure release to prevent system damage. The other options are incorrect because they do not accurately describe the fundamental difference in the operation of relief valves and safety valves.