Shut-off valve

Abstract

This utility model pertains to valve engineering, specifically shutoff and shutoff devices, and can be used in exhaust gas removal systems. The technical result of this utility model is aimed at increasing the reliability of automatic valve opening by ensuring guaranteed valve closure and maintaining its full functionality regardless of the state of the counterweights and the resistance at the shaft passages through the valve body, thereby eliminating the "slamming" effect during automatic valve opening. This technical result is achieved by the proposed chimney shutoff valve, comprising a body and a rotary flap in the gas flow cross-section with a shaft and welded stiffeners. The shaft is equipped with a key, and a transition sleeve is mounted on the shaft, equipped with a sector for free movement of the shaft key. The shutoff valve is also equipped with two electric drives, one for each flap.In turn, the center of mass of each rotary sash is shifted relative to the shaft axis by 50-300 mm due to the use of a counterweight. 2 ref. f-ly, 5 fig.

Description

[0001] This utility model relates to valve engineering, specifically shut-off and shut-off devices, and can be used in exhaust gas removal systems. The shut-off valve is designed to prevent sediment from entering chimneys and flue gas ducts, with an automatic opening function when pressure increases in the exhaust gas duct of boiler units at thermal power plants. The valves are available in round and rectangular cross-sections.

[0002] A flue gas valve from Powerz LLC is known, containing a housing and, in the gas flow section, a rotary valve with a supporting beam and welded stiffeners, elements that transmit the movement of the drive to the rotary valves (https: / / powerz.ru / products / klapany / dozhdevye-zaslonki / as of 12 / 25 / 2025).

[0003] The disadvantages of this valve include the lack of forced closing of the valve flaps, as well as the displacement of the center of gravity toward the center of the valve axis to ensure flaps close under gravity. This results in a flap "slamming" effect when the valve automatically opens when pressure increases. This flap "slamming" occurs when the flap opens any distance from the "Closed" position. At this point, exhaust gases are able to escape, and the pressure on the flap decreases, causing the flap to fall onto the valve's central beam. This continues until the source of exhaust gases is stopped or the valve is moved to the "Open" position using the actuator.

[0004] The closest analogue in its essence and the achieved result is the Emergency shut-off valve according to the Russian Federation patent 182641 (published on 08 / 24 / 2018), in which the central beam of the rotary valve is made in the form of a box in its central part and two pipe sections at the edges, shafts are fixed in the pipes with bolts for fastening, which rest on plain bearings fixed in bearing units, the length of the pipe sections is (0.1-0.15) the length of the beam, and in the flow section of the gas valve, several rotary units are created, which consist of the central beams are made in the form of a box in the central part and two pipe sections at the edges, shafts are fixed in the pipes with bolts for fastening, which rest on plain bearings fixed in bearing units, the length of the pipe sections is (0.1-0.15) beam length, torque from the drive mechanism on each rotary sash through the rocker arm, rod and lever,and the center of mass of each rotary valve relative to the shaft axis by 50-300 mm due to the use of a counterweight located on the inner side or on the outer side of each rotary valve in the direction of the gas flow so that the condition of the moment conditions is met.

[0005] The disadvantage of this valve is that it ensures the closure of the flaps solely by gravity.

[0006] The task that the claimed utility model is aimed at solving is to ensure the possibility of forced closing of the valve by transmitting force from the drive device to the valve shaft, as well as increasing the reliability of the automatic opening of the valve when the pressure in the exhaust duct increases, and eliminating the “slamming” effect when the valve is automatically opened.

[0007] The technical result of the utility model is aimed at increasing the reliability of the automatic opening of the valve by ensuring the guaranteed closing of the valve and maintaining its full functionality regardless of the state of the counterweights and the resistance at the points where the shafts pass through the valve body, and, consequently, eliminating the “slamming” effect during the automatic opening of the valve.

[0008] The technical result is achieved by the proposed chimney shut-off valve, comprising a housing and a rotary valve in the gas flow cross-section with a shaft and welded stiffeners. The shaft is equipped with a key, and an adapter sleeve is mounted on the shaft, providing a sector for the shaft key to move freely. The shut-off valve is also equipped with two electric drives, one for each valve. The center of gravity of each rotary valve is offset from the shaft axis by 50-300 mm through the use of a counterweight.

[0009] The problem is solved by introducing into the mechanism for transmitting force from the electric drive to the shaft of the rotary valve a transition sleeve having a sector for movement of the shaft key, thus ensuring free movement of the key along the sleeve sector during automatic opening and the possibility of forced closing of the valve.

[0010] The implementation of the proposed shut-off valve is explained by the drawings. Fig. 1 shows the general view of the round cross-section valve, Fig. 2 is a top view of the round cross-section valve, Fig. 3 shows a section A-A, Fig. 4 shows the position of the adapter sleeve in the "closed" position, Fig. 5 is the position of the adapter sleeve in the "open" position, where: 1 - body, 2 - flap shaft, 3 - flaps, 4 - counterweight, 5 - adapter sleeve, 6 - connecting axis, 7 - electric drive, 8 - key.

[0011] The chimney shut-off valve consists of a housing 1, in which shafts 2 with flaps 3 with stiffeners welded to them are installed, wherein the center of mass of each rotary flap 3 is shifted relative to the axis of the shaft 2 by 50-300 mm due to the use of a counterweight 4, which is installed on each flap 3. An automatic opening mechanism is installed on the shaft 2, consisting of an adapter sleeve 5, a connecting axis 6 and an electric drive 7. Moreover, the shaft 2 of each flap 3 is provided with a key 8, and the adapter sleeve 5 has a sector for the free movement of the key 8 of the shaft 2.

[0012] Electric drives 7 are used to open the 3 leaves. Each 3 leaf has its own electric drive. Electric drives 7 are mounted on the 2 shafts of the 3 leaves and are bolted to the support with a flange. A spherical radial hinge is located in the support.

[0013] This allows the valve to reliably close after automatic valve opening, regardless of the condition of the bearing assemblies, the distribution of mass on the valve, and other external factors. This, in turn, allows the center of mass of the valve to be shifted toward the opening direction, which increases the reliability of automatic valve opening and eliminates the effect of the valve flaps "slamming."

[0014] Description of the operation of the shut-off valve.

[0015] When the shut-off valve is forced open, the torque from the electric motor 7 is transmitted to each rotary flap 3 through the adapter sleeve 5 directly to the shaft 2, and the center of mass of each rotary flap 3 is shifted relative to the axis of shaft 2 by 50-300 mm due to the use of a counterweight 4 located on each rotary flap 3 in relation to the gas flow so that the condition of unequal mass of half of the flaps 3 is met. The use of counterweights 4, which are insignificant in mass in the design of the rotary flap 3, ensures the operation of the valve in automatic mode, thereby allowing the valve to operate as intended. The location of the counterweights is selected by calculation. Unlike the prototype, this shut-off valve has the ability to force closing, which made it possible to shift the center of mass of the valve in the opposite direction - the side of opening of the flaps, which increases the reliability of automatic opening, sinceWhen the sash is turned by 10-15 degrees, the counterweight deviates towards the opening, passes the center of mass and then opens sash 3 under the influence of gravity and remains in this position regardless of the decrease in pressure in the exhaust duct until sash 3 is forced to close using electric drive 7.

[0016] To enable automatic opening of the valve, in the event of an increase in pressure upstream of the valve above the set value, the adapter sleeve 5 has a sector for the free movement of the key 8 of the shaft 2. In the "Closed" state, when the pressure upstream of the valve increases above the set value, an emergency automatic self-opening of the valve occurs by rotating the flaps 3. When the valve is closed, the pressure acts on the entire surface of the flaps 3, but since the flaps 3 are designed with an offset of the axis of the shafts 2 relative to the center of the flaps as a whole, the pressure acts on one half of the flaps, relative to the shafts 2, with greater force than on the other. Due to the difference in pressure forces acting on one half of the flaps 3 and on the other half, relative to the shafts 2, the flaps 3 automatically rotates, and the valve moves to the "Open" position. Thus, when the pressure increases above the set value, the flaps 3 automatically rotate.

[0017] Return to the “Closed” position from the “Open” position occurs under the action of the electric drive 7, which eliminates the sudden uncontrolled movement of the flap 3 and the dynamic impact of the flap 3 on the central beam of the valve.

[0018] The use of this shut-off valve design, compared with a similar valve design, allows for the complete elimination of incomplete valve closure and loss of its functionality, increases the reliability of automatic valve opening when pressure increases, and eliminates the “slamming” effect when the valve automatically opens.

[0019] Valves of this design have successfully passed factory tests simulating all valve operating modes.

Claims

1. A chimney shut-off valve comprising a housing and a rotary valve in the flow section of the gas stream with a shaft and welded stiffeners, characterized in that the shaft is provided with a key, and a transition sleeve is installed on the shaft, provided with a sector for free movement of the shaft key.

2. A chimney shut-off valve according to paragraph 1, characterized in that it is equipped with two electric drives, one for each valve.

3. A chimney shut-off valve according to paragraph 1, characterized in that the center of mass of each rotary valve is shifted relative to the shaft axis by 50-300 mm due to the use of a counterweight.

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