closedvalve

Closedvalve is not a standard technical term, but is commonly used to describe a valve that is in the closed position, thereby isolating a section of a piping system. In this state, the closure member—such as a disc, plug, ball, or gate—seats against the corresponding seal to form a leak-tight barrier. The term emphasizes the functional condition rather than a specific device.

Valves are closed by various actuators, including manual handwheels or levers, and automated actuators driven by electricity, pneumatics, or hydraulics. The closed position is typically indicated by a position indicator or through control system feedback. In many installations, interlocks or programmable logic control ensure that a valve cannot be opened while other processes are unsafe.

Regardless of valve type, the closed position is defined by full engagement of the closure element with the seat. Seals may be soft seats (elastomer, PTFE) or metal-to-metal, chosen based on media, temperature, and pressure. Leakage classifications distinguish tight shutoff from minor seat leakage.

Common applications include isolation for maintenance, safety shutdowns, and prevention of backflow in emergency or process-control scenarios. Materials and pressure ratings vary by application, with valves standardized by specifications such as ANSI/ASME, API, or ISO. Proper sizing, actuation, and maintenance are essential to ensure reliable shutoff and long service life.