RU2285852C2 - Ball cock - Google Patents

Abstract

FIELD: valving.

SUBSTANCE: ball cock comprises housing that has inlet and outlet passages and receives valving member made of tubular piston mounted in the housing for permitting movement under the action of external pressure, sealing unit movably mounted with respect to the tubular piston, and passage that connects the butt between the sealing unit and tubular piston with the atmosphere. The valving member is mounted on two axles that are axially aligned and rigidly interconnected. One of the axles is connected with the driving mechanism through the pinion. The driving mechanism is made of rod that is set inside the housing out of the zone of the through passage and two bushings movably mounted on the rod. The bottom bushing-rack is mounted for permitting cooperation with the pinion. The top bushing-piston is mounted for permitting cooperation with the piston that is mounted above the top arrester of the bushing-rack and defines the hydraulic space together with the arrester. The space is filled with oil. The central section of the rod is provided with ring projection, and the openings in the bushings are step. The inlet and outlet passages are connected with the space above the top bushing-piston through the check valves.

EFFECT: enhanced reliability.

3 dwg

Description

The invention relates to pipe fittings, and in particular to valves with plugs having a spherical surface, and can be used for installation on technological lines of gas fields to block the flow of the transported medium.

A locking device is known that comprises a housing with inlet and outlet nozzles, a locking member, a composite seat, consisting of an inner ring and an outer seat made with a shoulder facing the sealing ring, which is located between the saddle rings, the outer ring being fixed motionless relative to the inner ring ( US patent No. 3617025, CL 251-172).

The disadvantage of this device is the low reliability due to a violation of the tightness of the shutter as a result of intense destruction of the surface layers of the o-ring during operation.

The closest set of essential features selected as a prototype is a ball valve containing a housing, a locking member, a saddle in the form of a tubular piston mounted in the housing with the ability to move under external pressure and a sealing assembly mounted movably relative to the tubular piston, and in the housing at the junction of the sealing unit and the tubular piston is made a channel connected to the atmosphere (AS No. 857608, F 16 K 5/20, 03/12/79).

The disadvantage of a ball valve is its low reliability, due to the complexity of controlling the tubular piston and the locking element.

The problem achieved by the invention is to create such a technical solution, by using which the reliability and economy of the ball valve is increased by sequential control of the tubular piston and the shut-off element by a single drive mechanism.

To achieve the named technical result, a shut-off body, a seat in the form of a tubular piston mounted for movement under the influence of external pressure, and a sealing assembly mounted movably relative to the tubular piston are placed in the housing of the ball valve with input and output channels, while the channel is made in the housing, connecting the junction of the sealing assembly and the tubular piston with the atmosphere.

The inventive ball valve differs from the prototype in that the shut-off element is mounted on two coaxial axes fixedly connected to it, one of which is connected by a gear with a drive mechanism made in the form of a rod located inside the housing outside the passage channel area, and two bushings, movably mounted on the rod, and having its upper and lower displacement limiters, the lower bushing-rack mounted with the possibility of interaction with the gear, while the upper bushing-piston is installed with the possibility of interaction with an external piston located above the upper limiter of the sleeve-rail, forming with it a hydraulic cavity filled with oil and serving as external pressure for the tubular piston, moreover, an annular protrusion is made in the central part of the rod, and holes with bushings are made stepwise, mating with the surfaces of the rod and its annular protrusions, while the inlet and outlet channels are connected through check valves to the cavity above the upper bushing-piston.

The invention is shown in the drawings, in which Fig. 1 shows a longitudinal section of a ball valve in the closed position, Fig. 2 is a section along A-A in Fig. 1, Fig. 3 is a section along BB in Fig. 2.

The ball valve contains a housing 1 with input 2 and output 3 channels. Inside the housing there is a locking member 4, a saddle in the form of a tubular piston 5, forming a cavity 6 with the housing, which is movably mounted under external pressure, and a sealing assembly 7 mounted movably relative to the tubular piston. Channel 8 is also made in the housing, connecting the junction of the sealing assembly and the tubular piston with the atmosphere.

The locking element is mounted on two axes 9 and 10 motionlessly connected to it, one of which 10 is connected by a gear 11 with a drive mechanism. The drive mechanism is made in the form of a rod 12 located inside the housing outside the zone of the passage channel. Two bushings are movably mounted on the rod, having their own travel stops - upper and lower 13, 14 and 15, 16, respectively. The lower sleeve-rack 17 is installed with the possibility of interaction with the gear. The upper sleeve-piston 18 is installed with the possibility of interaction with the piston 19 located above the upper 15 limiter of the sleeve-rail, and forming with it a hydraulic cavity 20 filled with oil. The hydraulic cavity serves as external pressure for the tubular piston and is connected to the cavity.

An annular protrusion 21 is made in the central part of the stem, and the inner surface of the holes of the bushings is made stepped, mating with the side surfaces of the stem and its annular protrusion.

The input and output channels of the housing are connected through check valves 22 and 23, respectively, with a cavity 24 above the upper sleeve-piston.

Ball valve works as follows. In the initial position (closed), the rod 12 together with the upper bushing-piston 18 are located in the highest position in which the bushing-piston 18 has reached its upper limiter 13. The lower bushing-rail 17 and the piston 19 are also in the uppermost position. The tubular piston 5 with the sealing unit 7 from the pressure side of the transported medium is pressed against the shut-off member 4, hermetically blocking the flow of the transported medium.

If necessary, open the ball valve to move the rod 12 down. The upper sleeve is a piston 18 under the pressure of the transported medium coming from the input (output) channel 2 (3) through the check valve 22 (23) into the cavity 24, moves down along with the rod 12. The piston sleeve 18 abuts the piston 19 and moves it down with a force that creates pressure in the hydraulic cavity 20 and the cavity 6 connected to it, significantly exceeding the pressure of the transported medium and allowing you to move the tubular piston 5 with the sealing unit 7 from the locking member 4. Moving the tubular piston 5 with the sealing evil 7 continues as long as the sleeve-piston 18 reaches its lower stop 14 and rod 12 continue their downward movement. With further downward movement of the rod 12, the annular protrusion 21 abuts against the lower bushing-rail 17 and together with it moves down. The sleeve-rail 17 thus rotates the locking element 4 through the gear 11. The opening of the passage by the locking element 4 continues until the rod 12 and the sleeve-rail 17 occupy the position corresponding to the full opening of the passage, in which the sleeve-rail 17 reaches its lower limiter 16.

If necessary, shut off the flow of the transported medium move the rod 12 up. The stepped sleeve-rail 17 under the action of the pressure of the transported medium, due to different effective cross-sectional areas at the ends, moves up together with the rod 12 and rotates the locking element 4 through the gear 11, closing the passage. The closure of the passage by the locking member 4 continues until the stepped sleeve-rail 17 occupies a position corresponding to the complete closure of the locking member 4, in which it reaches its upper stop 15 and the rod 12 continues its upward movement. With further upward movement of the rod 12, the annular protrusion 21 abuts against the upper sleeve-piston 18 and together with it moves up. The piston 19 under pressure in the hydraulic cavity 20 and the cavity 6 connected to it also moves upstream of the bushing-piston 18. At the same time, due to the pressure drop in the hydraulic cavity 20 and cavity 6, the tubular piston 5 with the sealing assembly 7 under pressure the transported medium is moved to the locking body 4, hermetically blocking the flow of the transported medium. The movement of the rod 12 with the sleeve-piston 18 upwards continues until the sleeve-piston 18 occupies a position in which it reaches its upper limiter 13.

Due to the simplification of the control of the tubular piston and the locking element by one drive mechanism, the reliability of the ball valve is increased.

Claims (1)

A ball valve comprising a housing with inlet and outlet channels, a locking member, a seat in the form of a tubular piston mounted in the housing with the ability to move under external pressure, and a sealing assembly mounted movably relative to the tubular piston, and a channel connecting the joint a sealing assembly and a tubular piston with an atmosphere, characterized in that the locking member is mounted on two coaxial axes fixedly connected to it, one of which is connected by a gear to the drive mechanism, filled in the form of a rod placed inside the housing outside the zone of the passage channel, and two bushings movably mounted on the rod and having their own limiters of movement - the upper and lower, and the lower sleeve-rack mounted with the possibility of interaction with the gear, while the upper sleeve-piston is installed with the possibility of interaction with a piston located above the upper limiter of the sleeve-rail and forming with it a hydraulic cavity filled with oil and serving as external pressure for the tubular piston, and in the central part of the rod an annular protrusion is made, and the holes in the bushings are made stepwise, mating with the surfaces of the rod and its annular protrusion, while the inlet and outlet channels are connected through check valves to the cavity above the upper piston sleeve.

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