Stopcock

The stopcock is a valve that completely frees the flow of a fluid in a pipe or completely off. A valve is actuated by a 90 ° rotation of the closing element. The construction of stopcocks is completely sealed; This applies both to the connected pipe as well as for the spindle of the actuator.

Unlike the shut-off valve in which the flow can be continuously adjusted according to need, the setting is not provided on intermediate positions at stopcocks. So shut-off valves have only two states - open or closed.

For plumbing and heating equipment is usually used for water valves, although they are often referred to as a tap ( faucet ). For gas shut-off valves are required. Shut-off valves are suitable for micro to large nominal sizes and pressure rating. You have to give the advantage to be tight for the pipeline be shut off and only the slightest leakage to the surroundings. They are therefore well suited for toxic, flammable or other dangerous fluids. They also have a low flow resistance. However, reliable operation is very limited due to contamination of the fluid. You can not control the fluid flow ( throttle ) them, and their space requirements in a pipeline comparatively large.

When closing the stopcock remains a small part of the medium in the bore of the closure member.

A tap is incorporated in a pipe, controlled leakage from a container, and is also a shut-off valve.

Types

Shut-off valves differ in the type of the closing element:

A distinction fittings with full and reduced bore. In special fittings can occupy more than one switching position a stopcock so that this tap is suitable for distributing and combining fluid streams. This arrangement is also known as multi-way valve, such as three-way cock.