Water Distribution Grade 1 Certification Practice Exam

What is the name of a type of valve that reduces the differential pressure across a closed disk making the main valve easier to operate?

1. Bypass Valve

2. Check Valve

3. Pressure Relief Valve

4. Float Valve

The correct answer is: Bypass Valve

The type of valve that reduces the differential pressure across a closed disk, thereby making the main valve easier to operate, is known as a bypass valve. This valve is specifically designed to allow a portion of the fluid to flow through it, effectively lessening the pressure differential that the main valve encounters during operation. This is particularly important in systems where high-pressure differentials can lead to difficulty in valve operation or can even cause mechanical failure. Bypass valves are often used in conjunction with other valves to ensure smoother operation and can improve the longevity and reliability of the valve system by reducing operational stress. In many applications, they help maintain a steady flow and pressure, facilitating the efficiency of the overall system without causing unnecessary wear or operational issues. Other types of valves mentioned have different functions: check valves are designed to ensure fluid flows in only one direction, pressure relief valves are used to release excess pressure to protect the system, and float valves are used to control liquid levels by opening or closing based on the float's position. Each of these serves a distinct purpose that does not align with the function of reducing differential pressure in the manner that a bypass valve does.