RU24224U1 - DEVICE FOR REPAIR OF A MAIN PIPELINE - Google Patents

Description

2002101085 MAIN PIPELINE

MKI 7 E 04 G 23/00

7 F 02 V 53/30 7 F 16 LI / 26

REPAIR DEVICE

A useful model applies both to the construction field and to the field of laying or replacing faulty pipes in the ground and can be used for repairing pipelines transporting, for example, gas condensate, oil, etc.

The main and most expensive element of the main pipeline is pipes welded into a continuous thread, which are the pipeline itself. During operation of the main pipeline on the pipes, the formation of through defects, for example, cracks, fistulas, through which the transported product leaks, is possible. As a result of this, both irretrievable loss of a part of the transported product and contamination of soil, groundwater and surface water occur. In addition, accumulation of heavy hydrocarbon vapors occurs near the outlet of the transported product, which creates a threat of ignition of the product coming from the main

pipeline through the through defect, and the threat of subsequent destruction of the main pipeline itself. Thus, the presence of through defects on the main pipeline creates an emergency. In these cases, the main pipeline is repaired.

A device is known for repairing a main pipeline without stopping the transport of a product using a tie-in under pressure (see "Technology of work on gas pipelines with a tie-in under pressure, including hot work RD 51-00158623-0995. M., 1994, S. 52-59).

This device includes a set of equipment, namely, an auxiliary bypass line, four additional split tees, two bypass pipes and six flat gate valves. Repair of a section of the main pipeline with a through defect is carried out in the presence of pressure in the main pipeline by means of an auxiliary bypass line. The auxiliary bypass line is arranged after four additional split tees, two bypass pipes, four flat gate valves and cuts of holes of a fixed diameter in the metal of the pipes of the main pipeline are mounted on the main pipeline, and these holes are cut in additional split tees with

using a special milling machine for cutting holes. At the same time, cutting a pipe section with a through defect and replacing the cut-off section of a new pipe is carried out with hot work after the cavity of the main pipeline is blocked, the transported product is expelled from the emergency section of the main pipeline and the inert gas of the emergency pipe section of the main pipeline is filled with inert gas.

The disadvantage of this device for repairing the main pipeline without stopping the transport of the product using the pressure cut-in is the need for the manufacture, installation and subsequent dismantling of the auxiliary bypass line, the irretrievable consumption of expensive split tees, the irretrievable loss of part of the transported product, the need for inert gas to fill the cavity of the main pipeline section . In addition, the disadvantage of this device for repairing the main pipeline without stopping the transport of the product using the inset under pressure is the need for a significant amount of excavation work related to the preparation of pits at the site of installation of at least four additional split tees.

As a prototype, a device was selected, namely, a bandage installed on a trunk pipeline having a leakage, i.e. end-to-end defect (see Khretinin I.S., Ivanov V.A., Paripsky A.V. et al. New methods for repairing trunk pipelines. -M.: VNIIEgazprom, 1990, p. 13-19).

This device, namely the bandage, is a detachable device consisting of upper and lower bearing shells, upper and lower unloading half rings, gaskets. The bandage is installed on the main pipeline having a leakage, i.e. a through defect, and the installation of the bandage is carried out without reducing the working pressure in the main pipeline, and the product flow during the installation of the bandage is compressed by the bandage itself.

The disadvantage of this device, namely, the bandage, is that the bandage does not eliminate the through defect, which is both a stress concentrator and a potential source of avalanche destruction of the main pipeline.

The technical effect of the proposed utility model consists in increasing the reliability of the main pipeline after repair work.

which is a detachable device consisting of upper and lower bearing shells, upper and lower unloading half rings, sealing gaskets according to the invention, includes a temporary technological patch and one split tee with a flange equipped with a plug, and the size of the temporary technological patch is defined as the dimensions of the through defect, as well as the dimensions of the cross section of the pipe of the main pipeline, and the thickness of the sealing strip of the temporary technological patch is determined as in the magnitude of its deformation, necessary to squeeze the product leak from the through defect, and the size of the gap between the main pipeline and the temporary technological patch required for welding, while the through defect and the temporary technological patch are removed after installing one split tee with a flange, moreover this detachable tee with a flange is installed on a temporary technological patch, while the diameter of the tap of a detachable tee with a flange exceeds the maximum the size of the temporary technological patch is not less than 20 mm.

Comparison of the claimed technical solution with the prototype allowed us to establish compliance with its criterion of "novelty. In the study of other well-known technical solutions in this field

The technical features that distinguish the claimed invention from the prototype have not been identified and therefore they provide the claimed technical solution with the criterion of “significant difference.

The utility model is illustrated by drawings.

In Fig.1 presents the emergency section of the main pipeline, and in Fig. 2 - 3 - technological stages of repair work using the inventive device. The main pipeline 1 has a through defect 2 to be repaired. For repair, a temporary technological patch 3 is used, equipped with a sealing gasket 4, as well as a split tee 5 with a flange, and a split tee 5 is equipped with a plug 6.

The following is a specific implementation of the inventive device.

In accordance with the operating rules, the main pipeline (1) is subjected to periodic air and (or) ground patrols. As a result of this periodic patrol, an emergency section of the main pipeline (1) is detected, on which the transported product leaks through the through defect (2), for example, through a fistula or a crack. Due to the fact that patrolling is carried out with an interval of up to twenty days, a through defect (2) is detected at the “initial stage of occurrence. At this stage, the volume of product resulting from

the main pipeline (1) through the through defect (2), allow you to implement a repair method based on the use of the inventive device.

If the emergency section of the main pipeline (1) is laid underground, then excavation work is performed to open the emergency section. The dimensions of the excavation pit are determined from the conditions for the placement of the necessary technological equipment for repair and the conditions for the safe repair work by a specialized team of repairmen. In this case, soil refinement in the vicinity of the pipe with a through defect (2) is carried out manually, without the use of impact tools.

For the emergency section of the main pipeline (1) laid on the ground, manual excavation of the soil under the pipe is carried out to a depth sufficient for the day of installation of the required technological equipment and repair work.

For the emergency section of the main pipeline (1), laid above ground, earthwork is not performed, however, preparatory work is being carried out to ensure safe conditions for repair work at heights.

Next, both the location and the geometric dimensions of the through defect are refined (2). To do this, in compliance with safety rules and using

of the corresponding tool, the emergency section of the main pipeline (1) is cleaned from corrosion protection.

In this case, the product coming from the main pipeline (1) through the through defect (2) is collected in special containers. The containers filled with the product are removed outside the repair site for subsequent disposal. To avoid accumulation of heavy hydrocarbon vapors within the repair site, the site is constantly ventilated by means of portable ventilation devices.

After cleaning the pipes of the emergency section of the main pipeline (1) from anticorrosive insulation, the location of the through defect (2) and its geometric dimensions are determined. In addition, sections of the pipe that fall into the zone of welding work carried out during repair are examined. According to the survey data, the final decision is made on the method of repairing the emergency section of the main pipeline (1): if there are no defects on the examined pipe sections, requiring a cut-out of part of the pipes of the main pipeline (1), then repairs are made using the inventive device.

pipe, corresponding to the pipe of the main pipeline (1) in terms of strength parameters and geometric dimensions, namely, wall thickness and diameter. A temporary technological patch (3) is provided by a sealing gasket (4) made of lead sheet. The thickness of the sealing gasket (4) of the temporary technological patch (3) is determined by both the value of its deformation necessary to squeeze the product leak from the through defect (2) and the gap between the main pipeline (1) and the temporary technological patch (3) necessary for welding operations for welding a temporary technological patch (3) to the pipe of the main pipeline (1) (Fig. 1).

In this case, the minimum size /.resр of the sealing strip (4) of the temporary technological patch (3) is determined by the formula Lyn sd + 60 mm, where sd is the maximum size of the through defect (2), and the minimum size L of the temporary technological patch (3) is determined taking into account the minimum size pr sealing gasket (4) and is calculated by the formula L Ly +100 mm.

A temporary process patch (3) equipped with a sealing gasket (4) is superimposed on the through defect (2) so that the through defect (2) is located in the central part of the temporary technological patch (3). Next is made

pressing the temporary process patch (3) to the pipe of the emergency section of the main pipeline (1) with a force sufficient both to squeeze the product leak from the through defect (2) and to provide the required clearance between the main pipeline (1) and the temporary technological patch (3 ) required for welding. The elimination of a product leak from a through defect (2) is determined by the presence or absence of product smudges on the pipe surface, as well as by the analysis of air pollution by product vapors near a temporary process patch (3). In the absence of product leakage and no gas contamination near the temporary technological patch (3), the surface of the pipe around the temporary technological patch (3) is prepared for welding work by welding the temporary technological patch (3) to the pipe of the main pipeline (1). Welding work on welding a temporary technological patch (3) to the pipe of the main pipeline (1) is carried out in compliance with safety precautions and the requirements of the operating rules of the main pipelines (1). During welding operations, air is constantly monitored for gas contamination by the vapors of the transported product.

Upon completion of welding work on welding a temporary technological patch (3) to the pipe of the main pipeline (1)

quality control of the weld is performed by non-destructive method.

Next, the selection and installation of an additional detachable tee (5) with a flange (Fig. 2). An additional detachable tee (5) with a flange is selected so that the diameter of the detachable tee (5) corresponds to the diameter of the pipe of the main pipeline (1), and the diameter of the tap of the detachable tee (5) exceeds the maximum size of the temporary technological patch (3) not less than twenty millimeters. Installation of the split tee (5) with the flange is carried out in such a way that the longitudinal axis of the tap of the split tee (5) passes through the center of the temporary technological patch (3).

After mounting the split tee (5) with the flange, it is welded to the pipe of the main pipeline (1). Upon completion of welding work on the welding of a split tee (5) with a flange to the pipe of the main pipeline (1), the quality of the weld is monitored non-destructively. Then, a flat gate valve and a milling machine for cutting a hole are mounted on the welded split tee (5) with a flange. The system is crimped using the “split tee (5) system — a machine for cutting holes and, subject to the production technology, cuts a hole in the pipe wall with a mill

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pipeline (1). The cut out template, consisting of a part of the pipe with a through defect (2), gaskets (4) and a temporary process patch (3), is removed from the pipe. After closing the flat valve, the milling machine is disassembled to cut the hole and the plug (6) is mounted on the split tee (5) (Fig. 3).

Next, anti-corrosion insulation of the repaired section of the main pipeline (1) and, if necessary, backfilling of the main pipeline (1) is carried out.

Repair of the main pipeline (1) with a through defect is carried out without stopping the transport of the product. To unify repair work, fittings and technological equipment are used, manufactured by one manufacturing company, for example, T.D. Williamson. APPLICANT:

MAIN ENGE1

/ 000 "SURGUTZHROZH.: D / 1M1Sh1IVANOV I.A.

Claims (1)

A device for repairing a main pipeline, namely a bandage installed on a through defect of a main pipeline and consisting of a detachable device consisting of upper and lower bearing shells, upper and lower unloading half rings, sealing gaskets, characterized in that it includes a temporary technological a patch and one detachable tee with a flange equipped with a plug, and the size of the temporary technological patch is determined by both the size of the through defect and the dimensions of the cross section of the pipe of the main pipeline, and the thickness of the sealing gasket of the temporary technological patch is determined both by the magnitude of its deformation, necessary to compress the product leak from the through defect, and the gap between the main pipeline and the temporary technological patch, necessary for welding, while eliminating the through defect and temporary technological patch is carried out after installing one detachable tee with a flange, and this detachable triple An IR with a flange is installed on a temporary technological patch, while the diameter of the tap of a detachable tee with a flange exceeds the maximum size of the temporary technological patch by at least 20 mm.