If you need to control the direction of flow (prevent flow from going in the wrong direction), you should use a:

If you need to control the direction of flow (prevent flow from going in the wrong direction), you should use a:

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

Answer: (B)

To prevent flow from going the wrong way, you need a one-way device that automatically blocks reverse flow. A check valve does exactly this: it opens to let fluid move in the intended direction and immediately closes when flow tries to reverse, stopping backflow. In practice, this protects pumps, compressors, and other equipment from reverse flow and helps maintain system prime and pressure. The other valves—globe, ball, and butterfly—are mainly used for isolating or throttling flow and do not inherently prevent backflow unless paired with a separate backflow prevention device.

To prevent flow from going the wrong way, you need a one-way device that automatically blocks reverse flow. A check valve does exactly this: it opens to let fluid move in the intended direction and immediately closes when flow tries to reverse, stopping backflow. In practice, this protects pumps, compressors, and other equipment from reverse flow and helps maintain system prime and pressure. The other valves—globe, ball, and butterfly—are mainly used for isolating or throttling flow and do not inherently prevent backflow unless paired with a separate backflow prevention device.