Where are swing type check valves typically used?

Swing type check valves are typically used on the discharge side of most pumps because they are designed to prevent backflow in systems where gravity or the pump's discharge pressure can force fluid in the reverse direction. When the pump operates, the flow opens the swing check valve, allowing fluid to pass through; if the flow stops or reverses, the valve closes by virtue of its weight and the fluid pressure against it, effectively preventing backflow. This characteristic makes them particularly suited for installation downstream of pumps to safeguard system integrity and efficiency.

The other options do not correctly align with the primary application of swing type check valves. For example, while they can be found in many systems, they are not ideal for the suction side of pumps because backflow can cause cavitation or other operational issues. High-pressure applications typically require valves designed to handle such conditions without risk of failure, which is not the primary function of a swing type check valve. Additionally, while swing check valves do offer some resistance to flow, they are not primarily selected for that quality; rather, the focus tends to be on their ability to prevent backflow while minimizing flow obstruction compared to other valve types.