Which valve offers the least resistance to flow?

The gate valve is designed specifically for allowing or blocking the flow of fluid with minimal resistance. When the gate is fully open, it creates a straight path for the fluid, which significantly reduces turbulence and pressure drops compared to other types of valves. This feature makes the gate valve especially effective for applications where the flow rate needs to be maximized, such as in water supply systems or pipelines.

In contrast, the globe valve has a more complex internal structure that causes increased turbulence and pressure loss, making it less efficient for flow. A ball valve, while offering good flow characteristics when fully open, can still introduce some restrictions due to the internal design. The check valve is used primarily to prevent backflow and is not designed for minimal flow resistance; its operation introduces additional friction and flow disruption.

Therefore, the gate valve is the best choice when it comes to ensuring the least resistance to flow in a piping system.