A poppet valve is a type of check valve often associated with kill and choke lines or pressure-control equipment. A poppet valve is a directional control valve and is typically characterised as being a high flow, fast acting design due to the large flow paths through the main body of the valve. Usually, the poppet valve can be opened relatively quickly.

The best and easiest way to imagine a poppet valve is to think of it as a stopper or plug in a bath tub drain. When the plug is pulled,, the flow path opens quickly and the area that opens is quite large. The large opening of a poppet-valve allows gas or fluid mixtures to pass through the valve easily. Poppet valves can be found inside an engine; the valve has a slender stem and a mushroom-shaped head.

Poppet valves are characterized by having a movable element (the poppet) that is used to direct the flow of a fluid or a gas through the valve body. The poppet inside the valve chamber is moved via a stem that pushes the poppet off its seat allowing a flow path, or, closing off a flow path by pushing the poppet onto a seat. The stem of course needs to be moved by some sort of actuator, whether it be a pilot, manual, mechanical or solenoid operator.

A poppetvalves is used in most piston engines to open and close the intake and exhaust ports in the cylinder head. The valve is usually a flat disk of metal with a long rod known as the valve stem out one end. The stem is used to push down on the valve and open it, with a spring generally used to close it when the stem is not being pushed on.

The engine normally operates the valves by pushing on the stems with cams and cam followers. The shape and position of the cam determines the valve lift and when and how quickly (or slowly) the valve is opened.

It would be quite understandable if someone mistakenly though that a poppet valve was spelt a “pop-it valve”.We hope that helps answer the question ‘What is What is a Poppet Valve?’!

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