RU2809294C1 - Closing device - Google Patents

Abstract

FIELD: pipeline equipment.

SUBSTANCE: closing device is designed to shut off existing pipelines through which gaseous and liquid substances are transported while maintaining transportation through the bypass outlet. The overlap is achieved by increasing the radial size of the annular elastic sealing element and its tight pressing against the inner wall of the pipeline as a result of uniform lateral compression between the fixed disk and the movable disk, which are configured for relative axial movement. The installation of a drive unit based on a hydraulic motor and a worm-gear drive unit on the closing unit, as well as the choice of a trapezoidal cross-sectional shape of the annular elastic sealing element, ensures the creation of a reliable and safe design for effective operation on real high-pressure pipelines with a large pipe diameter, having an elliptical cross-section, as well as at the welds of the pipeline and in the presence of corrosive deposits and defects inside the pipeline.

EFFECT: creation of a reliable and safe design for effective operation on real high-pressure pipelines.

8 cl, 6 dwg

Description

Field of technology

The invention relates to the field of pipeline transport intended for the movement of gaseous and liquid substances, including natural gas, water, oil and petroleum products. It can be repeatedly used to shut off an existing pipeline under pressure and carry out subsequent repair and restoration work. The closing device allows you to completely shut off a section of the pipeline that is subject to emergency or scheduled repairs and ensure continuous transportation through the bypass branch. The use of a closing device is possible on almost any pipeline under high pressure, including a main pipeline with a large diameter pipe.

State of the art

The “Shut-off device for pipelines” is known according to the patent for the invention of the Russian Federation RU 2100685, published on December 27, 1997, which allows you to close the end sections of pipelines during hydraulic tests and repair work. This overlap is achieved by compressing and subsequently increasing the diameter of a coupling made of rigid and elastic materials installed in the pipeline between fixed and movable flanges placed on the axial rod and made capable of relative movement using a threaded connection of the axial rod and nut.

The shut-off device for pipelines contains a movable flange made integral with an axial rod with a thread at the end, which fits into the hole of a stationary flange resting on the shell and an additional fastening flange, which is held on the end part of the pipeline by means of a nut and a rod. Between the movable and stationary flanges there is a set of gaskets made of elastic material, which are enclosed between annular conical couplings made of rigid material.

In a device installed at the end of the pipeline, due to the rotation of the nut, the movable flange approaches the fixed flange, providing compression of the gaskets, which consequently increase in diameter. At the same time, the annular conical couplings are compressed and, due to this, straightened, which also correspondingly increase in diameter. The relative movement of the flanges stops when the annular conical couplings rest with their outer edges against the internal walls of the pipeline with simultaneous abutment of the elastic gaskets against these walls.

A pipeline shut-off device cannot be installed on an active pipeline under pressure without first shutting it off and draining it. The installed device does not allow continuous transportation of the substance transmitted through the pipeline.

Known for “Tool for closing a pipeline, assembly and method of use” under US patent application US 2022/0290793, published 09/15/2022.

The tool for closing a pipe section includes a pipeline access unit, a transition unit, and an insulating unit. The pipeline access assembly is configured to insert and remove the insulating assembly through an opening in the wall of the pipeline. The transition unit is configured to attach the body of the pipeline access unit to the pipe, and connect the piston and clamp of the pipeline access unit to the insulating unit by means of a connecting unit. The insulating unit includes a sealing module containing ring sealing elements, the movement and pressing of which against the inner wall of the pipe is carried out using a liquid under pressure supplied through a chamber installed in the insulating unit.

The pipeline closing tool can be used on an existing pipeline under pressure. The disadvantage of this tool is low reliability due to the possibility of loss of tightness due to wear of the ring sealing elements as a result of repeated use or exposure to heterogeneous corrosion deposits on the inner surface of the pipe. This can lead not only to a decrease in insulating properties, but also to liquid entering the pipeline, creating pressure on the ring sealing elements, which can cause emergency situations.

It is known "Pipe closing device using an inflatable element" according to US patent US 3774647, published on November 27, 1973.

The device closing the pipeline contains an attachment to the pipeline in the form of a welded fitting around a hole previously made in the pipe. The shut-off valve assembly is implemented using a shut-off valve. The pipeline access unit is made in the form of a supporting body through which a movable rod is passed. A closing assembly is attached to its lower end using a rotating joint assembly. In the closing unit containing two parallel disks mounted on one shaft, a sealed chamber is formed using a ring-shaped elastic sealing element fixed between the edges of the disks. Gas under pressure is supplied to this chamber by means of a hose passed through the supporting body. In the initial state, the closing unit fits freely into the pipeline. As a result of the supply of gas under pressure into the sealed chamber, the ring-shaped elastic sealing element expands until it is tightly pressed against the inner wall of the pipeline along its entire circumference, blocking the pipeline. After the supply of gas under pressure has been stopped and the diameter of the ring-shaped elastic sealing element has been reduced, the pipeline closing device can be removed from the pipeline in a known manner.

The specified device can only be used to shut off low-pressure pipelines due to the small contact area of the ring-shaped elastic sealing element with the inner surface of the pipeline. In addition, the device has significant limitations on the structural strength of the closing unit, since the gas pressure in the sealed chamber, pushing the ring-shaped elastic sealing element from the inside, must significantly exceed the pressure in the pipeline acting on this element from the outside.

The “Device for cleaning and plugging pipelines” is known according to US patent US 4202377, published on 05/13/1980.

Based on the totality of common essential features, the technical solution for this patent for an invention was chosen as a prototype.

A device for cleaning and plugging pipelines contains

- attachment to the pipeline, providing a rigid and tight connection to the pipeline,

- a shut-off valve assembly, rigidly and hermetically attached to the attachment to the pipeline,

- a unit for drilling a through hole in the wall of the pipeline at the point where the attachment unit is connected to the pipeline through the shut-off valve unit and the attachment unit to the pipeline,

- a pipeline access unit that provides controlled penetration into the internal part of the pipeline through a shut-off valve assembly and a pipeline attachment unit, including a rod made in the form of a hollow tube, located in the pipeline access unit, partially immersed in the internal space of the pipeline with the ability to move in relation to to the attachment point to the pipeline,

- a sealing unit that ensures tightness in the access point to the pipeline when the rod moves,

- pressure relief unit from the inside of the pipeline access unit,

- an articulation unit attached to the end of a rod designed to be inserted into the internal space of the pipeline,

- a closing unit attached to the articulation unit and designed to pass through the access unit to the pipeline, the shut-off valve unit and the attachment unit to the pipeline into the internal part of the pipeline, consisting of a fixed disk and a movable disk placed parallel to each other on the shaft and made with the possibility of axial movement on it when the shaft rotates, between which an annular elastic sealing element is installed,

- a drive unit that provides controlled rotation of the drive shaft from a source that creates torque,

- a transmission unit that converts the rotational motion of the drive shaft into the translational motion of a movable disk relative to a stationary disk using bevel-toothed rotating gears, the axes of which are secured with bearings.

A device for cleaning and plugging pipelines makes it possible to completely shut off a pipeline under pressure, for example an existing gas pipeline, while maintaining its functionality without prior shutdown.

The prototype has the following main disadvantages:

- the impossibility of using it for high-pressure pipelines with a large pipe diameter, since the application of force to bring together the movable and stationary disks of the closing assembly in only one place, in the center along the longitudinal axis, is not enough for the necessary tight pressing of the annular elastic sealing element, which located in the peripheral annular region of these disks,

- low reliability due to the complexity of the design of the mechanical drive unit with a cardan joint and the insufficient strength characteristics of the transmission unit, which uses only two toothed rotating gears, for pipelines with high operating pressure,

- low safety due to the presence of technical personnel at the installation site of the specified device on the pipeline to perform manual mechanical rotation of the drive unit, which may be damaged in the event of an accident,

- greater complexity of using the device due to the complexity of installing its structure and working with it, as well as increased costs for repair work.

The essence of the invention

The use of this technical solution ensures high tightness of the closing device at high pressure of the transported substance in large-diameter pipelines, increasing reliability and safety, as well as reducing the cost of repair work.

This positive effect is achieved due to the fact that

- the drive unit is made combined with a source that creates torque, in the form of a hydraulic motor, powered from an external oil station using inlet and outlet hoses and installed directly on the body of the closing unit, made in the form of a bowl, the edge of which is pressed and attached to the rear peripheral surface of the fixed disk ,

- the transmission unit is installed directly on the closing unit and is made on the basis of a worm (gear-screw) gear containing a worm installed inside the housing of the closing unit, made in the form of a bowl, the edge of which is pressed and attached to the rear peripheral surface of the fixed disk, located coaxially with the axis hydraulic motor, the upper end of the worm is rigidly attached to the axis of the hydraulic motor, the opposite parts of the worm are fixed inside the body of the closing unit using bearings, the central part of the worm on both opposite sides is engaged with the left worm wheel mounted on the left shaft, and the right worm wheel mounted on the right shaft, left shaft and right shaft are located perpendicular to the worm, their upper parts are secured using bearings installed in the body of the closing unit,

- in the fixed disk of the closing unit, in oppositely located peripheral areas, there are two through holes in which bearings are installed, which are supporting elements for the central parts of the left shaft with a mounted left worm wheel and the right shaft with a mounted right worm wheel of the transmission unit located inside them,

- in the movable disk of the closing unit, in oppositely located peripheral areas, two holes are made, inside of which nuts are installed, into which the threaded lower parts of the left shaft with a mounted left worm wheel and the right shaft with a mounted right worm wheel of the transmission unit are screwed,

- the access unit is made in the form of a cylindrical casing, having a lower open end equipped with a flange, which is rigidly and hermetically connected to the shut-off valve assembly, and an upper closed end, which houses two quick-release connections through which the inlet hose and outlet hose are passed, connected to oil stations.

In the closing device, the central part of the worm of the transmission unit is engaged on both opposite sides with an additional left worm wheel mounted on an additional left shaft, and with an additional right worm wheel mounted on an additional right shaft, the additional left shaft and the additional right shaft are located perpendicular to the worm , their upper parts are secured with the help of additional bearings installed in the body of the closing unit, their central parts are passed through two additional through holes made in the fixed disk with two additional support bearings installed in them, and their threaded lower parts are screwed into nuts installed in two additional holes of the movable disk so that the left shaft, the right shaft, the additional left shaft and the additional right shaft form a pairwise symmetrical configuration in the peripheral regions of the fixed and movable disks of the closure assembly.

In the closing device, the internal surfaces of the fixed disk and the movable disk of the closing assembly are equipped with peripheral conical bevels, the annular elastic sealing element is made in a trapezoidal cross-section, and its outer side, corresponding to the base of the trapezoid and adjacent to the inner surface of the pipeline, is equipped with external annular protrusions.

In the closing device, the pressure relief unit is made in the form of a fitting rigidly and hermetically attached to the upper side part of the cylindrical casing, to which a ball valve is connected.

In the closing device, in the casing of the pipeline access unit, there is a hole with a rigid and sealed outlet attached to it, which provides a bypass for the exit of the substance transported through the pipeline, bypassing the section of the pipeline blocked by the closing device.

In the closing device, the sealing unit is made in the form of a cuff inserted into a groove made inside a through hole in the upper part of a cylindrical casing having an internal diameter smaller than the diameter of the rod.

In the closing device, the shut-off valve assembly is made in the form of a flat gate valve equipped with a pressure equalization valve in the attachment point to the pipeline and the access point to the pipeline, the upper end of which is equipped with a flange that is rigidly and hermetically attached to the flange of the casing of the access point.

In the closing device, the rigid connection of the upper end of the worm of the transmission unit to the axis of the hydraulic motor of the drive unit is made in the form of a vertically located coupling, one end of which covers the axis of the hydraulic motor, and the opposite end covers the upper end of the worm.

Brief description of drawings

In the following, the invention is illustrated by specific examples of its implementation with reference to the attached figure (Figure 1), which shows a general view of the closing device in section with the closing unit in working position, figure (Figure 2), which shows the vertical central longitudinal section of the closing unit, drawing (Figure 3), which shows a vertical cross-section of the closing unit with a left worm wheel and a right worm wheel along arrows A-A in Figure 2, drawing (Figure 4), which shows a horizontal longitudinal section of a closing unit along arrows B-B in Figure 3, drawing (Figure 5), which shows a vertical cross-section of the closing assembly with a left worm wheel, a right worm wheel, an additional left worm wheel and an additional right worm wheel, drawing (Figure 6), which shows a cross-section of the peripheral region of the stationary disk, peripheral region of the movable disk and cross-section of the annular elastic sealing element.

Carrying out the invention

The closing device 1 (Figure 1) contains a fastening unit to the pipeline 2, made in the form of a fitting 3, the first end of which is welded externally to the pipeline 2, covering a hole previously made in it at the repair site using a drilling machine, and a flange is made at the second end.

The shut-off valve assembly is implemented in the form of a flat gate valve 4, equipped with a pressure equalization valve in the attachment point to the pipeline and the access point to the pipeline, tightly pressed from above to the fitting flange 3.

The pipeline access unit contains a cylindrical casing 5, having a lower open end equipped with a flange, which is rigidly and hermetically connected to a flat gate valve 4 on top of it, and an upper closed end, which houses two quick-release connections 6, through which the supply hose 7 and outlet hose 8 connected to the oil station 9.

In the cylindrical casing 5 of the pipeline access unit there is a hole with a rigid and sealed outlet 10 attached to it, which provides a bypass for the exit of the substance transported through the pipeline, bypassing the section of the pipeline blocked by the closing device.

The pressure relief unit is made in the form of a fitting 11, rigidly and hermetically attached to the upper side part of the cylindrical casing 5, to which a ball valve 12 is attached.

The pipeline access unit, which provides controlled penetration into the internal part of the pipeline through the shut-off valve assembly and the attachment to the pipeline, includes a rod 13 made in the form of a hollow tube.

The sealing unit, which ensures tightness in the access point to the pipeline when the rod 13 moves, is made in the form of a cuff 14 inserted into a groove made inside the through hole in the upper part of the cylindrical casing 5, having an internal diameter smaller in size than the diameter of the rod 13.

The articulation unit attached to the end of the rod 13, intended for immersion into the internal space of the pipeline 2, contains a base 15, to which a holder 17 is attached using a hinge 16 with the ability to rotate around the axis of the hinge 16. A closing unit 18 is rigidly attached to the holder 17.

The closing unit 18 (Figure 2) includes a housing 19, made in the form of a bowl, the edge of which is pressed and attached to the rear peripheral surface of the fixed disk 20, as well as a movable disk 21, between which an annular elastic sealing element 22 is installed. The housing 19 of the closing unit is supported from below in the working position using the support roller 23. When the rod 13 moves downwards, the closing unit in the pipeline is turned into the working position using the lower sliding roller 24 and the upper sliding roller 25 installed in the lower part of the rear cover attached to the housing 19 of the closing unit.

The drive unit (Figure 2) is made combined with a source that creates torque, in the form of a hydraulic motor 26, mounted directly on the housing 19 of the closing unit, and powered from an external oil station 9 using an inlet hose 7 and an outlet hose 8 (Figure 1).

The transmission unit (Figure 2 and Figure 3) is installed directly on the closing unit and is made on the basis of a worm (gear-screw) gear containing a worm 27 installed inside the housing 19 of the closing unit, located coaxially with the axis of the hydraulic motor 26. The upper end of the worm is rigidly attached to axis of the hydraulic motor using a clutch 28. The opposite parts of the worm are secured inside the housing of the closing unit using the upper bearing 29 and the lower bearing 30, equipped with a bearing cover 31. The central part of the worm 27 on both opposite sides is engaged with the left worm wheel 32, mounted on the left shaft 33, and with the right worm wheel 34 mounted on the right shaft 35. The left shaft 33 and the right shaft 35 are located perpendicular to the worm 27. The upper part of the left shaft 33 (Figure 4) is fixed in the housing 19 of the closing unit using a bearing 36. The upper part the right shaft 35 is fixed in the housing 19 of the closing unit using a bearing 37.

In the fixed disk 20 (Figure 4) of the closing unit, in oppositely located peripheral areas, two through holes are made in which a bearing 38 is installed, which is a supporting element for the central part of the left shaft 33 of the worm wheel 32 located inside it, and a bearing 39, which is a supporting element for the located inside it is the central part of the right shaft 35 of the worm wheel 34.

In the movable disk 21 of the closing unit (Figure 4), in oppositely located peripheral areas, two holes are made, inside which a nut 40 is installed, into which the threaded lower part of the left shaft 33 of the worm wheel 32 is screwed, as well as a nut 41, into which the threaded lower part is screwed. part of the right shaft 35 of the worm wheel 34.

In the transmission unit (Figure 5), the central part of the worm 27 on both opposite sides is engaged with an additional left worm wheel 42, which is mounted on an additional left shaft 43 and an additional right worm wheel 44, which is mounted on an additional right shaft 45.

By analogy with the left shaft 33 and the right shaft 35, the additional left shaft 43 and the additional right shaft 45 are located perpendicular to the worm 27, their upper parts are secured using two additional bearings installed in the housing of the closing unit 19, their central parts are passed through two additional through holes , made in a stationary disk 20 with two additional support bearings installed in them, and their threaded lower parts are screwed into nuts installed in two additional holes of the movable disk 21 so that all four shafts of the worm wheels of the drive unit form a pairwise symmetrical configuration in the peripheral areas fixed and movable disks of the closing unit.

The internal surfaces of the fixed disk 20 and the movable disk 21 of the closing unit (Figure 6) are equipped with peripheral conical bevels 46 and 47. The annular elastic sealing element 22 is made in the cross section of a trapezoidal shape, and its outer side, corresponding to the base of the trapezoid and adjacent to the inner surface of the pipeline, equipped with external ring-shaped projections 48.

The method of using a closing device for carrying out repair and restoration work on a pipeline under pressure includes the following steps.

Weld the lower end of the fitting 3 from the outside to the pipeline 2 in the required place (Figure 1).

Install a flat gate valve 4, equipped with a pressure equalization valve, in the attachment point to the pipeline and the access point to the pipeline, pressing it tightly from above to the fitting flange 3, ensuring the necessary rigidity and tightness.

Mount a specialized tap-in drilling machine onto a flat gate valve 4 and open it.

Using a specialized drilling machine for tapping, a through hole is drilled in the pipeline 2 with a core cutter of the required diameter, which passes through a flat gate valve 4 and fitting 3.

After removing the core cutter, the flat gate valve 4 is closed and the drilling machine for tapping is dismantled.

Install the remaining components of the closing device in assembled form (Figure 1) with a tightly closed outlet 10 that implements a bypass for the exit of the substance transported through the pipeline, bypassing the pipeline section blocked by the closing device, onto a flat gate valve 4 and open it.

The rod 13 is lowered into the pipeline 2 using a pipeline access unit, which provides controlled penetration into the interior of the pipeline 2 through a flat gate valve 4 and fitting 3.

The closing assembly 18 is rotated from its original vertical position to a working horizontal position (Figure 2) due to the rotation of the holder 17 relative to the base 15 using the hinge 16 and the stop of first the lower sliding roller 24, and then the upper sliding roller 25 into the wall of the pipeline 3.

The closing unit 18 is inserted into the pipeline 2, since in the initial state the outer diameter of the annular elastic sealing element 22 is less than the internal diameter of the pipe of the pipeline 2.

The housing 19 of the closing unit 18 is fixed and supported in working position from below using a support roller 23.

Turn on the oil station 9 and supply oil under pressure to the hydraulic motor 26 through the inlet hose 7 and outlet hose 8 connected to it.

The worm 27 is rotated using a hydraulic motor 26 (Figure 3).

The left worm wheel 32 and the right worm wheel 34 are driven into rotation by means of the worm 27, and thus the left shaft of the worm wheel 33 and the right shaft of the worm wheel 35 are rotated.

In the closing unit, the movable disk 21 (Figure 4) is moved towards the fixed disk 20 due to the threaded connection of the lower part of the left worm shaft 33 and the nut 40 installed in the movable disk 21, as well as due to the threaded connection of the lower part of the right worm shaft 35 and the installed there are 21 nuts 41 in the movable disk.

The annular elastic sealing element 22 located between the peripheral internal surfaces of the fixed disk 20 and the movable disk 21 of the closing unit is compressed due to their relative proximity.

The outer surface of the annular elastic sealing element 22 is pressed tightly against the inner surface of the pipeline 2 due to an increase in its radial size as a result of its deformation due to lateral compression (Figure 2).

The oil station 9 is turned off while maintaining the relative position of the fixed disk 20 and the movable disk 21 due to the frictional force in the threaded connections and, thus, ensure a constant high tightness of the closing assembly 18 (Figure 1).

The outlet 10 is opened if it is necessary to implement a bypass for the exit of the substance transported through the pipeline, bypassing the section of the pipeline blocked by the closing device.

Removal of the closing device and its extraction from the pipeline after completion of repair and restoration work is carried out by performing similar actions in the reverse order.

The outlet 10 is closed if it was opened in order to implement a bypass for the exit of the substance transported through the pipeline, bypassing the section of the pipeline blocked by the closing device.

The direction of oil flow is changed by turning on the reverse mode at the oil station 9 itself or by swapping the inlet hose 7 and outlet hose 8 at the quick-release connections 6 (Figure 1).

The oil station 9 is turned on and oil under pressure is supplied through the inlet hose 7 and outlet hose 8 connected to it to the hydraulic motor 26 in the opposite direction.

The worm 27 is rotated using a hydraulic motor 26 in the opposite direction (Figure 3).

By means of the worm 27, the left worm wheel 32 and the right worm wheel 34 are driven into rotation, and thus the left shaft of the worm wheel 33 and the right shaft of the worm wheel 35 are rotated in the opposite direction.

The movable disk 21 is moved in the closing unit away from the fixed disk 20 due to the threaded connection of the lower part of the left worm shaft 33 and the nut 40 installed in the movable disk 21, as well as due to the threaded connection of the lower part of the right worm shaft 35 and installed in the movable disk 21 nuts 41 (Figure 4).

The annular elastic sealing element 22 located between the peripheral internal surfaces of the fixed disk 20 and the movable disk 21 of the closing unit is released due to their relative expansion.

The outer surface of the annular elastic sealing element 22 is pressed from the inner surface of the pipeline 2 by reducing its radial size as a result of removing its deformation due to lateral compression and returning it to its original position when the outer diameter of the annular elastic sealing element 22 is less than the internal diameter of the pipe of the pipeline 2 .

Turn off the oil station 9.

The closing unit 18 is removed from the pipeline 2 by lifting the rod 13 upward.

The closing unit 18 is rotated from the working horizontal position to the initial vertical position by further raising the rod 13 to its upper position and rotating the holder 17 relative to the base 15 using the hinge 16, as well as by focusing first on the upper sliding roller 25, and then on the lower sliding roller 24 into the wall of the pipeline 3.

Move the rod 13 to its uppermost position until it stops at the inner upper surface of the cylindrical casing 5,

Close the flat gate valve 4.

Open the ball valve 12 to relieve the residual pressure of the substance transported through the pipeline in the inner part of the cylindrical casing 5 of the access unit.

Remove the remaining components of the closing device 1 in assembled form from the closed flat gate valve 4 of pipeline 2.

The closing device is disassembled for ease of storage and transportation.

A device for inserting the plug into the fitting, which can be used as a drilling machine, is mounted on a flat slide valve.

Open the flat gate valve 4.

Install the plug into fitting 3.

Dismantle the device for inserting the plug into fitting 3.

Remove flat gate valve 4 from fitting 3.

Install the cover on fitting 3 welded to pipeline 2.

The closing device can be used for high pressure pipelines with large pipe diameters. This is ensured by the application of force to bring together the movable and stationary disks of the closing assembly and lateral compression of the annular elastic sealing element placed between them, not in one place along the central axis of the pipeline as in the prototype, but in two places or even four places in the peripheral areas of these disks. This is quite sufficient for the necessary tight, uniform pressing of the outer surface of the annular elastic sealing element against the inner wall of the pipeline and ensuring the required tightness under conditions of high pressure in the pipeline.

The closing device can be used for real high-pressure pipelines with a large pipe diameter, which have not a circular, but an elliptical cross-sectional shape, as well as in places where the pipeline is welded and in conditions of the presence of corrosive deposits and defects inside the pipeline. This is achieved not only due to uniform peripheral lateral compression of the annular elastic sealing element, but also by providing the internal surfaces of the fixed disk and the movable disk of the closing assembly with peripheral conical bevels, as well as by making the annular elastic sealing element in a trapezoidal cross-section with its outer side, corresponding to the base of the trapezoid and adjacent to the inner surface of the pipeline, equipped with outer ring-shaped projections. The pressing of such an annular elastic sealing element in a relatively wide strip of the inner annular surface of the pipeline and its plastic deformation make it possible to tightly cover the internal protrusions and recesses from welds and corrosion deposits, providing a high degree of sealing.

The closing device is highly reliable due to the drive unit being combined with a source that creates torque, in the form of a hydraulic motor powered from an external oil station and installed directly on the body of the closing unit. Refusal to use numerous mechanical drive elements with a universal joint from an external source, used in the prototype, completely eliminates the possibility of their breakdowns and damage.

The installation of a transmission unit on the closing unit and the use of a worm in it, attached to the axis of the hydraulic motor and engaged on both opposite sides in the first version with two worm wheels, and in the second version with four worm wheels, made it possible to create a simple, reliable and durable design , capable of transmitting high forces to ensure lateral uniform compression of the annular elastic sealing element and work effectively under high pressure conditions in a large diameter pipeline.

The industrial applicability of the closure device for pipeline repairs was confirmed through factory and field testing on an 800 mm diameter pipeline. The working pressure reached 2.4 MPa. The test pressure was one and a half times higher than the working pressure and reached 3.6 MPa. The mass of the closing device was 3550 kg, and the overall dimensions were 4900×1450×1210 mm.

The closing device is intended for long-term repeated use during repair and restoration work on pipelines used for transporting various gaseous and liquid substances, including natural gas, water, oil and refined petroleum products. The material of the ring elastic sealing element must be resistant to the influence of the substance transmitted through the pipeline. In the case of pumping petroleum products through a pipeline, a ring elastic sealing element made of oil and petrol resistant rubber is installed in the closing device. When using a closing device on pipelines through which various substances are transported, only the annular elastic sealing element must be replaced.

Claims (24)

1. Closing device for closing the cross-section of an existing pipeline under pressure of a substance transported through it, containing - attachment to the pipeline, providing a rigid and hermetically sealed connection to the pipeline, - a shut-off valve assembly, rigidly and hermetically attached to the attachment to the pipeline, - a unit for drilling a through hole in the wall of the pipeline at the point where the attachment unit is connected to the pipeline through the shut-off valve unit and the attachment unit to the pipeline, - a pipeline access unit that provides controlled penetration into the internal part of the pipeline through a shut-off valve assembly and a pipeline attachment unit, including a rod made in the form of a hollow tube, located in the pipeline access unit, partially immersed in the internal space of the pipeline with the ability to move in relation to to the attachment point to the pipeline, - a sealing unit that ensures tightness in the access point to the pipeline when the rod moves, - pressure relief unit from the inside of the pipeline access unit, - an articulation unit attached to the end of a rod designed to be inserted into the internal space of the pipeline, - a closing unit attached to the articulation unit and designed to pass through the access unit to the pipeline, the shut-off valve unit and the attachment unit to the pipeline into the internal part of the pipeline, consisting of a fixed disk and a movable disk placed parallel to each other on the shaft and made with the possibility of axial movement on it when the shaft rotates, between which an annular elastic sealing element is installed, - a drive unit that provides controlled rotation of the drive shaft from a source that creates torque, - a transmission unit that converts the rotational movement of the drive shaft into the translational movement of the movable disk relative to the stationary disk using bevel-toothed rotating gears, the axes of which are secured with bearings, characterized in that in order to increase the tightness of the closing device at high pressure of the transported substance in large-diameter pipelines, increase reliability and safety, as well as reduce the cost of repair work - the drive unit is made combined with a source that creates torque, in the form of a hydraulic motor, powered from an external oil station using inlet and outlet hoses and installed directly on the body of the closing unit, made in the form of a bowl, the edge of which is pressed and attached to the rear peripheral surface of the fixed disk , - the transmission unit is installed directly on the closing unit and is made on the basis of a worm (gear-screw) gear containing a worm installed inside the housing of the closing unit, made in the form of a bowl, the edge of which is pressed and attached to the rear peripheral surface of the fixed disk, located coaxially with the axis hydraulic motor, the upper end of the worm is rigidly attached to the axis of the hydraulic motor, the opposite parts of the worm are fixed inside the body of the closing unit using bearings, the central part of the worm on both opposite sides is engaged with the left worm wheel mounted on the left shaft, and the right worm wheel mounted on the right shaft, left shaft and right shaft are located perpendicular to the worm, their upper parts are secured using bearings installed in the body of the closing unit, - in the fixed disk of the closing unit, in oppositely located peripheral areas, there are two through holes in which bearings are installed, which are supporting elements for the central parts of the left shaft with a mounted left worm wheel and the right shaft with a mounted right worm wheel of the transmission unit located inside them, - in the movable disk of the closing unit, in oppositely located peripheral areas, two holes are made, inside of which nuts are installed, into which the threaded lower parts of the left shaft with a mounted left worm wheel and the right shaft with a mounted right worm wheel of the transmission unit are screwed, - the pipeline access unit contains a cylindrical casing having a lower open end equipped with a flange, which is rigidly and hermetically connected to the shut-off valve assembly, and an upper closed end, which houses two quick-release connections through which the inlet hose and outlet hose are passed, connected to the oil station. 2. The device according to claim 1, characterized in that the central part of the worm of the transmission unit on both opposite sides is engaged with an additional left worm wheel mounted on an additional left shaft, and with an additional right worm wheel mounted on an additional right shaft, an additional the left shaft and the additional right shaft are located perpendicular to the worm, their upper parts are secured with the help of additional bearings installed in the body of the closing unit, their central parts are passed through two additional through holes made in the stationary disk with two additional support bearings installed in them, and equipped their lower parts are threaded into nuts installed in two additional holes of the movable disk so that the left shaft, the right shaft, the additional left shaft and the additional right shaft form a pairwise symmetrical configuration in the peripheral regions of the fixed and movable disks of the closing assembly. 3. The device according to claim 1, characterized in that the internal surfaces of the fixed disk and the movable disk of the closing assembly are equipped with peripheral conical bevels, the annular elastic sealing element is made in the cross section of a trapezoidal shape, and its outer side, corresponding to the base of the trapezoid and adjacent to the inner surface pipeline, equipped with external ring-shaped projections. 4. The device according to claim 1, characterized in that the pressure relief unit is made in the form of a fitting, rigidly and hermetically attached to the upper side part of the cylindrical casing, to which a ball valve is attached. 5. The device according to claim 1, characterized in that in the casing of the pipeline access unit there is a hole with a rigid and sealed outlet attached to it, which provides a bypass for the exit of the substance transported through the pipeline, bypassing the section of the pipeline blocked by the closing device. 6. The device according to claim 1, characterized in that the sealing unit is made in the form of a cuff inserted into a groove made inside a through hole in the upper part of the cylindrical casing, having an internal diameter smaller than the diameter of the rod. 7. The device according to claim 1, characterized in that the shut-off valve assembly is made in the form of a flat gate valve equipped with a pressure equalization valve in the attachment point to the pipeline and the access point to the pipeline, the upper end of which is equipped with a flange that is rigidly and hermetically attached to the flange access node casing. 8. The device according to claim 1, characterized in that the rigid connection of the upper end of the worm of the transmission unit to the axis of the hydraulic motor of the drive unit is made in the form of a vertically located coupling, one end of which covers the axis of the hydraulic motor, and the opposite end covers the upper end of the worm.

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