Shut-off valve: useful information

The shut-off valve is an element of pipeline valves used in various situations. In such a device, the movement of the locking member is parallel to the axis of the main fluid flow inside.

Shut-off valves with an electric executing mechanism are oriented to change the flow rate of the working medium, which moves through the pipeline. The shut-off valve can be made of bronze, steel and cast iron, it is used to adjust the liquid or gas flow through the pipeline, and also as an element that blocks this flow. If we take the design features of the device as its basis, as well as its purpose, then there is also an electromagnetic shut - off valve that allows the medium to be controlled in the system at a distance, as well as the flanged and clutch types of valves.

There are many varieties of this type of reinforcement. The choice of a certain one depends on the features of the technological process, as well as on the tasks that are placed on the safety shut-off valve. An important factor are the types of systems where it is used.

Valves are widely distributed, fulfilling the functions of shut-off valves, which allows to ensure a high-quality sealing in the shut-off organ, while the design of the device is quite simple. Valves are used for gaseous and liquid media with a wide range of operating properties: pressure and temperature. They are usually used on pipelines that have a small diameter, since for larger sizes one has to face a situation where the force required to control the valve increases substantially, and the structure becomes more complicated to ensure a correct fit of the closure placed on the seat ring.

The shut-off valve has a number of advantages:

- possibility of use in conditions of increased pressure and temperature, vacuum, aggressive and corrosive environments;

- Simplicity of repair and technological maintenance directly in operation.

On the design features valves are similar in many ways to valves, however, the principal difference is the way the valve is moved, which gives the valves additional advantages:

- for a full opening requires a small shutter stroke, so the mass and height of the device is also quite small;

- tightness of the valve in the valves is much easier to provide than in the valves;

- when opening and closing the valve, the friction of the seal is almost impossible, which significantly reduces the degree of its wear;

- as a seal of the valve, the use of a bellows is allowed.

The safety shut-off valve has certain drawbacks:

- high hydraulic resistance, which, with a significant diameter of the passage and high velocity of the medium, creates significant energy losses, which causes the need to increase the initial pressure in the system;

- The diameter limits the application limits of the valve;

- in most constructions there are stagnant zones, where there is an accumulation of mechanical impurities from the working medium, and this considerably increases the corrosion in the valve body.

In any case, this type of reinforcement is widely used.