A gate valve is a linear flow control device that uses a flat or wedge-shaped disc to block or allow fluid passage through a pipe. The disc moves perpendicular to the flow direction, providing either fully open or fully closed positions. Gate valves are not suitable for throttling applications and should be operated in fully open or fully closed states only.
Technical Details
Gate valves feature a simple design with minimal pressure drop when fully open, typically rated for DN15 to DN600 sizes. They require multiple handle turns to operate and can develop seat wear if used for modulating control. Most gate valves are designed for on-off duty rather than continuous throttling in HVAC systems.
Applications in HVAC
Gate valves serve as isolation valves in main water supply lines, pump discharge lines, and boiler connections. They are commonly installed in equipment rooms where system isolation is needed for maintenance. Their low-cost design and reliable sealing make them standard in residential and light commercial installations.
Practical Significance
While economical, gate valves should never replace control valves for temperature or flow regulation. Proper installation requires adequate space for handle operation and periodic maintenance to prevent corrosion and sticking.