RU2303739C1 - Pipe localizing device - Google Patents

Abstract

FIELD: pipeline transportation, possible use for repairing pipelines with replacement of defective section by a maintenance "coil".

SUBSTANCE: in accordance to invention, collapsible yoke with flanges for fastening on the pipeline is made in form of tubular cylindrical structure with possible movement of device in assembled state along the pipeline due to presence of a gap between outward diameter of pipeline and internal diameter of yoke. On the ends of yoke, conic branch pipes are fastened for accepting pipe ends in the yoke, and in middle section of the yoke along perimeter windows are made for accessing junctions of pipes and the maintenance "coil".

EFFECT: expanded arsenal of technical means.

2 dwg

Description

The invention relates to the field of construction and repair of the main pipeline for transporting liquids and gases, and is intended for the repair of the pipeline with the replacement of the defective area repair "coil".

When repairing a pipeline, a defective section is first discovered, a pit is excavated to release the pipeline, a defective section is cut out, the pipes are centered; mark, install and weld the repair "coil" with the pipes of the pipeline.

The centering of the pipes is due to the fact that after cutting the defective area, the remaining pipes are displaced in the horizontal and vertical planes due to the presence of stresses in the pipeline due to temperature changes, soil movement, etc. Deviation from alignment can reach 3 ... 20 mm or more.

An analysis of the production experience of repair work on the main pipelines shows that three methods of repair are used: a) without the operation of centering the pipes; b) centering the pipes using various devices; c) centering using stresses on the pipes in order to achieve their alignment.

In the first repair method, the marking of the repair “coil” is much more complicated, the repair process becomes very time-consuming. In the second repair method, very complex and metal-intensive equipment is used, the installation of which takes a long time. The third repair method is also very labor intensive, the need to use lifting equipment, and in some cases equipment for plastic pipe deformation.

A device support for maintaining the pipeline / 1 /. It contains a base with racks, balancing levers with bushings placed on racks movably with height adjustment. A suspension with rollers that support the pipeline is pivotally mounted on the balancing levers. The device allows you to center the pipe, however it is difficult and metal-intensive in design, its installation takes a fairly long time.

A known method of preparing pipes for welding when replacing a defective section of the main pipeline / 2 /, the essence of which is that when marking and trimming the repair "coil" and the connected pipe ends, the sizes and shapes of the pipe ends are compared with a standard circle whose diameter is equal to nominal diameter of the pipeline being repaired. Ensuring the coincidence of the sizes and shapes of the ends of the pipes is carried out before mounting the “coil” by plastic deformation of the metal of the pipes due to the distributed force on the ends of the pipes. This operation eliminates the ellipse of the pipes formed when cutting the pipes in a plane not perpendicular to their axis.

The disadvantages of the method are the great complexity of plastic deformation, the need to use special equipment, the difficulty of ensuring accurate marking of pipe joints. In fact, the marking of pipes and “coils” is done by fitting, which reduces the productivity and quality of repairs.

Closest to the technical nature of the present invention is a device for centering pipes / 3 /, providing fixation of pipes before cutting the defective area. The device consists of two cast clamps installed at the ends of the pipes. The clamps are firmly fixed to the pipes by means of flanges with bolts. Stringers are threaded through holes in the tides of one of the clamps, on which the movable stops are successively mounted, and stringers are then threaded into the tide holes of the second clamp. The construction of clamps, stringers and stops centers the pipes and the repair coil.

The device allows to increase labor productivity during repair work, the accuracy of centering pipes and repair "coil".

However, the device has drawbacks in the complexity of the design of the device, the high complexity of mounting it on the pipeline. In addition, the device makes it difficult to access the pipeline for installing a “coil” and conducting marking and welding operations, which creates inconvenience and reduces labor productivity. In addition, the accuracy of the centering of the pipes is ± 3 ... 5 mm, which is due to the fact that the pipeline is not fixed along its entire length, but only in two places (fixing points of clamps).

The present invention is aimed at simplifying the process of centering pipes, improving the accuracy of centering and marking of pipe joints and repair "coils", reducing the complexity of marking and installation work and improving the quality of repairs.

The problem is solved in that in the device for centering the pipes during the repair of the main pipeline with the replacement of the defective section with a repair “coil” containing a detachable clamp with flanges for mounting it on the pipes, the clamp is made in the form of a single tubular cylindrical structure with the ability to move it in assembled condition along the axis of the pipeline due to the gap between the outer diameter of the pipes and the inner diameter of the clamp, while at the ends of the clamp conical pipes are mounted for the ends of the pipes to enter into it, and in the middle of it STI around the perimeter of the window made for access to the pipe joints and repair "coil".

The device for centering the pipes is illustrated in the drawing, which shows the section of the pipeline being repaired in longitudinal and transverse sections, which shows the device for centering the assembly, repair "coil" and connected pipes.

The proposed device for centering the pipes is a single tubular cylindrical structure 1 with conical nozzles 2 mounted at its ends, that is, the device is a single clamp put on the pipe at the joints of pipes 3, 4 and repair "coil" 5. The clamp consists of two halves connected by flanges 6 with bolts. The conical nozzles 2 serve to facilitate the entry of the ends of the pipes 3, 4 into the clamp.

The clamp is installed on the pipeline with a gap between the outer diameter of the pipes and the inner diameter of the clamp in order to ensure the possibility of its movement in assembled form along the axis of the pipeline. The size of the gap does not exceed the tolerance on misalignment of pipes and is equal to 0.5 ... 1.5 mm.

In the middle part of the structure, windows 7 are made around the perimeter for access to the joints of pipes and the repair coil. To move the clamp along the axis of the pipeline, handles 8 are provided.

Centering pipes and marking the repair "coil" using the device is as follows. First, the defective section of the pipeline is cut out strictly in planes perpendicular to the axis of the pipeline. Next, they clean and cut the edges of the pipe joints for welding. After that, based on the distance between the pipes, taking into account the length of the cut defective section and the gap at the joints of the pipes and the "coil", the length of the repair "coil" is determined and made.

After preparatory work, a repair “coil” 5 is installed between the pipes 3 and 4 using the pipe layer 5. Next, in the area of the first joint, for example, between the “coil” 5 and pipe 4, mount the device half and fasten them with bolts, while the windows 7 of the clamp should be opposite junction. After mounting the clamp, the pipe 4 and the "coil" 5 will be in coaxial position.

Next, through the windows 7, a preliminary “tack” is made by welding of the pipe 4 and the repair “coil” along the length of the windows in four places, after which the device is moved along the pipeline axis to the left to the area of the second joint. When the clamp approaches the pipe 3, the conical pipe 2 is put on the pipe 3. The possible misalignment of the pipe 3 and the repair coil 5 is eliminated by the action of the inner surface of the conical pipe 2, as well as the displacement of the pipe 3 in horizontal and vertical planes using a pipe layer. After that, the clamp is finally installed so that the windows 7 are against the junction of the pipe 3 and the repair coil 5. Then a tack is made by welding the mating parts along the length of the windows 7.

After tacking both joints, the device is disassembled and dismantled, after which both joints are finally boiled.

Compared with the prototype invention, the present invention has the following technical and economic advantages:

1. The proposed device is much simpler in design, has no cast parts and is an ordinary pipe without any additional parts. The cost of manufacturing the device is 3-5 times less than the cost of the prototype device.

2. The process of centering the pipes using the proposed device is simplified, since the centering of the pipes and their alignment are provided immediately after the installation of the device in the joint area without additional adjustment using the stops, as is done in the prototype device. Centering performance is increased by 10 ... 20% compared with the prototype.

3. The proposed device provides a more accurate centering of the pipes and the repair "coil", as they are fixed not in two places, as in the prototype device, but over the entire contact area of the clamp and pipe surface. The accuracy of centering the pipes using the proposed device reaches ± 1 ... 2 mm

4. More accurate centering of the pipes helps to improve the accuracy of the marking of the repair "coil" and the joints of pipes with the "coil", which, in turn, improves the quality of welds and, therefore, the quality of repair.

5. The simplicity of the design of the proposed device, the low complexity of its installation and the simplification of the centering of the pipes as a whole can increase the productivity of repair work in 1.5-2 times compared with the prototype.

The present invention can be used for repair work on pipelines.

Information sources

1. RF patent No. 2079761, M.cl. F16L. Support device for supporting the pipeline.

2. RF patent №2123922, M.cl. B23P 6/00; B23K 33/00. A method of preparing pipe ends for welding when replacing a defective section of a trunk pipeline.

3. RF patent №2217650, M.cl. F16L 1/036. Device for centering pipes.

Claims (1)

A device for centering pipes, containing a detachable clamp with flanges for mounting on pipes, characterized in that the clamp is made in the form of a single tubular cylindrical structure with the ability to move it in an assembled state along the axis of the pipeline, while conical pipes are mounted at the ends of the clamp, and the middle part of the perimeter made windows.