Which statement about gate valves is true?

• A. Gate valve is a linear-type valve
• B. Gate valve is a rotary-type valve
• C. Gate valve is used only for check flow
• D. Gate valve cannot isolate sections

Answer: (A)

Gate valves operate with the closure member moving straight in and out along the pipe axis. That straight-line, sliding motion is what defines them as linear-type valves. When opened, the gate lifts or slides away to leave a wide, unobstructed path for flow; when closed, the gate seals against seats to give a tight shut-off. This makes them ideal for isolating sections of a water distribution system, since they provide reliable shut-off with minimal flow resistance when fully open, and strong isolation when closed. They aren’t rotary-type devices like ball or butterfly valves, which use rotation of a closure member, and they’re not limited to checking flow—they’re commonly used specifically to isolate portions of the system.