Check valves: principle of operation, scope of application, advantages

Check valves are used as protective pipe fittings for high-pressure systems. Pipeline fittings are designed to protect changes in the flow of the working medium from changes in their direction. With their help, pipelines, installations, vessels, pumps for various purposes are effectively protected. The valve is irreplaceable in case of emergency situations, as it prevents the reverse flow of the medium.

Areas of application of fittings

The check valve automatically passes the medium only in a certain direction, which is indicated by an arrow on the device body.

Check valves are used for various installations:

• in hydraulic drives, which consist of a set of pumps, in order to prevent mutual impact during simultaneous operation of the equipment;
• in filter blocks, which are mounted in reversible hydraulic installations for the movement of the liquid medium through the filter block only in a given direction;
• in hydraulic drives with closed circulation of the working fluid as make-up valves;
• in installations where constant fluid movement in one direction is required.

Fittings are necessary in sewer and water supply systems, in the autonomous heating circuit, in the system of accounting mechanisms, the installation of a pumping unit and for the operation of other equipment.

The principle of operation of the valve

Check valves made of steel control the movement of the working flow due to the spool, which moves in a vertical position. Under the influence of a flow of liquid or other substance, the spool rises, thereby opening a passage in the direction that is necessary for the functioning of the system. After the movement of the working flow of the medium, the shut-off body is installed on the seat. As a result, the reverse flow of the liquid is prevented. The valve is operated automatically. Check valves are installed on horizontal sections of pipelines in the direction of the working medium flow.

The main types of fittings

Mechanical fuses have a large number of versions. On this site you can get acquainted with the popular models. All products have a durable steel body. There are devices that differ in the following parameters:

• according to the size of the passage section of the device: 15.0-25.0 mm;
• depending on the type of spool: ball, disc, double-leaf;
• according to the installation method – coupling, flanged or welded valves;
• in the direction of flow – angular or through;
• according to the type of material – brass, plastic, steel valves;
• depending on the method of closing – by means of a spring, under the weight of the device.

Advantages of check valves

The device has undoubted advantages, including:

• automatic control;
• high maintainability;
• increased resistance to fluid flows;
• the valve materials are made of wear-resistant materials of high hardness;
• resistance of the structure to corrosion processes, mechanical damage, external factors;
• application in different climatic conditions;
• possibility of use for aggressive environments;
• the valve seal is operable at a wide temperature range of the conducted medium: -60 ⁰ C-+560 ⁰ C;
• high tightness of the shutter;
• average service life – at least 20 years;
• easy installation and maintenance.

The check valve in the water supply and sewerage system protects pipes from water shocks and pressure surges, protects equipment from emergency situations and stabilizes the pressure in the system.