RU220175U1 - Self-acting magnetic valve - Google Patents

Abstract

The proposed technical solution relates primarily to compressor engineering and can be used in the design of piston compressors, air motors, vacuum pumps and other machines. The self-acting magnetic valve contains a seat with passage channels, a locking element in the form of a magnet, a lift limiter with radial channels, a clamping element in the form of a magnet, a pin and a nut, while the shutting element in the form of a magnet and the clamping element in the form of a magnet face each other with like poles , and the shut-off element is located in a rubberized shell, and a centering pin is installed in the body of the saddle. The proposed self-acting magnetic valve makes it possible to increase the probability of failure-free operation of magnetic self-acting valves and increase the tightness of the valve by at least 30%.

Description

The utility model relates primarily to compressor engineering and can be used in the designs of piston compressors, air motors, vacuum pumps and other machines.

Known for “Self-acting ring valve with a point spring” [Piston compressors. Volume 2. Fundamentals of design. Constructions. – 3rd ed., revised. and additional – M.: Kolos, 2008. – 711 p., l. ill.: ill. – (Textbooks and teaching aids for students of higher educational institutions, p. 664), which contains a saddle with passage channels for the gas medium, a lift limiter with channels for the exit of the gas medium, a locking element in the form of a plate, a point spring that presses locking element to the seat, studs in accordance with GOST 22038-76 and nuts in accordance with GOST 5915-70.

This technical solution has the following disadvantage. The absence of an elastic element (for example, in the form of rubber) on the shut-off element leads to leakage of the compressible medium even when the valve is closed. The presence of a spring as a clamping element of the locking element leads to restrictions on operating parameters, namely the speed of rotation of the crankshaft; the range of rotation of the crankshaft is limited to about 3000 rpm. The use of a point spring leads to a decrease in the service life and reliability of the self-acting valve in aggressive operating environments.

The closest technical solution for the same purpose (prototype) is the “Self-acting valve” [RU 2601331], which contains a seat with passage channels, locking elements located in the grooves of the lift limiter, the passage channels of which are formed by alternating concentric rows of radially elongated holes and holes in the form of ring sectors. Each row of radially elongated holes is located in plan above the annular row of locking elements, with each of the holes located above two adjacent locking elements of the row and communicating with the grooves in which they are located. A number of annular sectors are placed between the rows of locking elements and communicate with several grooves of adjacent rows at once. At least three channels are connected to each limiter groove: two radial holes and at least one annular sector. The locking elements are pressed against the seat by means of a pair of permanent magnets facing each other with like poles installed in the lift limiter and in the locking element, respectively. However, the given example does not exclude the possibility of using springs for the same purpose.

This technical solution has the following disadvantages. The absence of a safety damper on the surface of the magnets can lead to their destruction in a collision; after complete or partial destruction of the magnets, this valve becomes completely inoperable. The absence of an elastic element (for example, in the form of rubber) on the shut-off element leads to leakage of the compressible medium even when the valve is closed.

The technical objective of the utility model is to increase the probability of failure-free operation of magnetic self-acting valves and increase the tightness of the valve by at least 30%.

The technical problem is solved by creating a self-acting valve with a magnetic shut-off element located in a rubberized shell, which makes it possible to increase the reliability and tightness of magnetic self-acting valves. The proposed self-acting magnetic valve can serve as both a discharge and suction valve.

The proposed design is illustrated by drawings, where:

fig. 1 shows a self-acting discharge magnetic valve assembly, tightened with a pin;

fig. Figure 2 shows a self-acting suction solenoid valve assembly, secured with a pin.

The self-acting magnetic valve consists of a seat 1 with passage channels 2, a shut-off element made in the form of a magnet 3 located in a rubberized shell 4, a lift limiter 5, a clamping element 6 made in the form of a magnet, with magnetic elements 3 and 6 facing each other with the same poles, radial passage channels 7, centering pin 8, the seat with the lift limiter is tightened by means of a pin 9 and tightened with a nut 10.

The proposed self-acting magnetic valve works as follows. During the compression process, gas enters the passage channels 2, when the gas pressure drop exceeds the adhesive force of the shut-off element 3, located in the rubberized shell 4, the shut-off element will rise (open) and communicate the passage channels 2 with the radial passage channels 7, and the injection process will begin. The lifting height of the shut-off element 3 is limited by the lift limiter 5. When the pressure in the working chamber becomes less than the pressure behind the self-acting magnetic valve, the shut-off element 3, through the action of the pressing element 6, will disconnect the passage channels 2 from the radial passage channels 7, the injection process will end. During the processes of reverse expansion, suction and the beginning of compression, the tightness of the working chamber is ensured by “crushing” the rubberized shell 4 through the adhesion force of the locking element 3 with the seat 1. The presence of a rubberized shell 4 helps prevent the destruction of the locking organs 3 in the event of their sudden collision.

The technical problem is solved by creating a self-acting valve with a magnetic shut-off element located in a rubberized shell, which makes it possible to increase the reliability and tightness of magnetic self-acting valves.

The tightness of a self-acting valve is assessed by the gas flow flowing through the valve in the closed state. For an incompressible fluid, the equation has the following form [Plastinin P.I. Piston compressors. Volume 1. Theory and calculation / 2nd ed., revised. and additional – M.: Kolos 2000. – P. 162 (formula 6.3)]:

where α is the flow coefficient;

f is the nozzle exit cross-sectional area, ^m2 ;

ρ ₀ - gas density in the vessel from which the outflow occurs, kg/m ³ ;

P ₀ , P - gas pressure in the vessel from which the outflow occurs, Pa.

In turn, the product αf is denoted by Ф and is called the equivalent area [Plastinin P.I. Piston compressors. Volume 1. Theory and calculation / 2nd ed., revised. and additional – M.: Kolos 2000. – P. 164 (formula 6.10) and P. 282]:

Ф= αf= πDδ (2)

where D is the diameter of the flow section, m;

δ is the conditional gap along the entire perimeter of the contact of the shut-off body with the seat, µm.

Hence, equation (1) takes the form:

As can be seen from formula (3), the smaller δ, the less gas will flow through the valve in the closed state. Currently, the conventional clearance for various types of valves with a metal or fluoroplastic shut-off element is 0.25-1 microns. [Valves of piston compressors. Textbook for full-time and part-time students of specialty 240801 "Machines and apparatus for chemical production" / State Educational Institution of Higher Professional Education "Russian Chemical Technical University named after D.I. Mendleev", Novomoskovsk Institute (branch), Compiled by: Dodin Yu.S., Klochkov V. I., Lukyanitsa A.I. Novomoskovsk, 2009, - P. 5.], [Busarov I.S., Guselnikov D.V., Burlakov Yu.A., Solomkin A.A. The influence of leakage of self-acting valves on the integral characteristics of low-speed, long-stroke compression stages // Equipment and technologies of petrochemical and oil and gas production. Materials of the 9th international scientific and technical conference. 2019. pp. 132-133]. Using the proposed self-acting valve, the nominal clearance is reduced by crushing the rubber shell of the shut-off element and filling with rubber the micro-irregularities of the contact surface of the shut-off element to the seat. Taking into account the required roughness parameters for sealing collars of seats with shut-off bodies - Ra = 0.32 [Plastinin P.I. Piston compressors. Volume 2. Fundamentals of design. Constructions. – 3rd ed., revised. and additional – M.: KolosS, 2008. – 656 p., l. ill.: ill. – Textbooks and textbooks. Benefits for higher education students Textbook establishments], then the minimum gain in reducing the nominal gap will be:

Accordingly, according to formula (4), leakage of compressed gas through a closed valve is reduced by at least 30%.

Claims (1)

A self-acting magnetic valve containing a seat with passage channels, a shut-off element in the form of a magnet, a lift limiter with radial channels, a clamping element in the form of a magnet, a stud and a nut, while the shut-off element in the form of a magnet and the clamping element in the form of a magnet face each other in the same way poles, characterized in that the shut-off element is in a rubberized shell, and a centering pin is installed in the body of the saddle.