poppet valve

mechanical device

Also known as: mushroom valve, perpendicular valve

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Last updated

July 2, 2026

Quick Summary

A poppet valve is a type of valve used in mechanical engineering to control the flow of fluids. It features a movable element, typically a disk with a tapered edge, that rises perpendicularly to or from its seat. This design allows it to open, shut, or partially obstruct a passageway.12

Poppet valves are commonly found in gasoline engines, where they regulate the intake and exhaust of gases into cylinders. They can also function as safety valves, opening automatically when fluid pressure exceeds a set limit. The movement of the poppet valve is often controlled by cams, springs, and pushrods.134

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valve
On gasoline engines, poppet valves are used to control the admission and rejection of the intake and exhaust gases to the cylinders. In the Figure (right centre), the valve, which consists of a disk with a tapered edge attached to a shank, is held against the tapered seat…
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On gasoline engines, poppet valves are used to control the admission and rejection of the intake and exhaust gases to the cylinders. In the Figure (right centre), the valve, which consists of a disk with a tapered edge attached to a shank, is held against the tapered seat…
Read More

gasoline engine
Valves, pushrods, and rocker arms
…all the so-called poppet, or mushroom, valves, consisting of a stem with one end enlarged to form a head that permits flow through a passage surrounding the stem when raised from its seat and that prevents flow when the head is moved down to contact the valve seat formed in…
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…all the so-called poppet, or mushroom, valves, consisting of a stem with one end enlarged to form a head that permits flow through a passage surrounding the stem when raised from its seat and that prevents flow when the head is moved down to contact the valve seat formed in…
Read More