What type of valve is typically used to prevent backflow in a pipeline?

• A. Ball valve
• B. Gate valve
• C. Check valve
• D. Butterfly valve

Answer: (C)

A check valve is specifically designed to prevent backflow in a pipeline. It allows the fluid to flow in one direction while automatically closing if the flow reverses, thereby stopping any backward movement of the fluid. This mechanism is crucial in various applications to ensure that the flow remains unidirectional, which can protect pumps and equipment from damage caused by backflow.

In contrast, ball valves and butterfly valves are primarily designed for on/off service and do not inherently prevent backflow without additional features. While gate valves can control the flow of fluid, they do not provide any protection against backflow either. These other types of valves serve different functions and are not equipped with the same one-way flow capabilities as check valves, which are specifically engineered for this purpose.