RU2450194C2 - Procedure and device for repair of pipelines as per pipe-in-pipe system - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: method of repairing metal pipelines by putting pipes inside; protective cases are put on the ends of the pipeline under repair. A case is made as two coaxial cylinders made of elastic sheet with connected bases. An elastic sheet is inserted into the end of a repaired pipeline and pressed against the inner surface of the pipeline. Then, the sheet is folded, pressed against the outer surface of the pipeline under repair and fixed. After installing protective cases on the ends, steel or polyethylene pipes are put through inside the repaired pipeline.

EFFECT: extended performance and reliability of pipeline repair, extended inventory of technical means.

2 dwg

Description

The invention relates to the construction of pipelines and can be used in the repair of pipelines by the method of "pipe in pipe".

A known method of repairing pipelines using pulling steel or polyethylene pipes inside a damaged [1, 2], which consists, in particular, in preliminary preparation of the edges of the repaired pipeline by deburring, sharp, cutting edges of the pipe after cutting the coil in order to exclude insulation damage for repair steel pipes and pipe bodies - for repair polyethylene, and the damage for the latter should not exceed 10% of the pipe wall thickness [3].

There is also a method of repairing pipelines using pulling flexible pipes, including “stockings”, which consists, in particular, in preliminary preparation of the edges of the pipeline being repaired by deburring, sharp, cutting pipe edges after cutting the coil [4].

These methods have a significant drawback, which consists in the low productivity of the technological operation “preparation of the edges of the repaired pipeline”, which is carried out after cutting the coils on both sides of the repaired pipeline by a torch or pipe cutting machine. In addition, when cutting coils with a torch, splashes of molten metal fall inside the pipe and, solidifying there, damage the body of the drawn pipe, reducing or completely negating the reliability of the repair.

The objective of the invention is to increase the productivity of preparing the edges of the repaired pipeline while ensuring the reliability of the repair.

The problem is solved due to the technical result, which consists in changing the technology of repairing pipelines by the method of "pipe in pipe", which significantly increases the productivity and reliability of the repair.

The specified technical result is achieved by the fact that the proposed method does not carry out the technological operation “preparation of the edges of the repaired pipeline” after cutting the coils with either a hand tool or a grinder.

The outer surface of the pipe being pulled is protected by installing a protective case on the edges of the pipeline being repaired. The case is a device consisting of two coaxial cylinders 1 connected by bases (Fig. 1), put on the ends of the repaired pipeline with an interference fit or clamped to the outer surface of the pipeline with a collar 2. In order to reduce the friction forces, the possibility of shear and entrainment of the case by the repair pipe, by the case has a chamfer 3 at the output end of the pipeline being repaired and is installed on the pipe end with interference.

When repairing pipelines of large diameters 4, in order to reduce the dimensions of the cases, which is especially convenient when transporting and storing them, the cases are made in the form of sheets of elastic material 1. In this case, the sheet is inserted into the pipeline being repaired and pressed against the inner surface of the pipeline by a spacer ring 5, then the sheet is bent, pressed and fixed to the outer surface of the pipeline being repaired with a collar 2. Moreover, on the receiving side of the inserted pipe, the case may not be attached to the inner surface of the mounted pipeline (Fig. 2).

The application of the method is especially effective when the pipeline is completely ruptured (especially the underwater passage and when the damaged pipeline has torn edges) and, if necessary, the fastest recovery of the transportation of the pumped product.

In this case, the ends of the cables are fed from both ends of the damaged pipeline [4]. The diver throws (in case of a small diameter of the damaged pipeline) the ends of the cable into the protective cases and connects them. Then the protective cases are installed, after which the repair pipe is drawn in one direction or another. If the damaged pipeline has a large diameter, then at first the rings 5 (Fig. 2) are threaded to the ends of the cable, then they are interconnected, sheets of elastic material are passed into the pipeline, fixed with rings 3, sheets of elastic material are bent, pressed to the outer surface the pipeline being repaired with a clamp 2.

Bibliography

1. Technological regulations for the restoration of worn pipeline communications by introducing sections of polyethylene pipes into them. - Ufa: UGNTU, 2004, 37 p.

2. SP34-116-97 Instruction for the design, construction and reconstruction of oil and gas pipelines. - M.: VNIIST, 1998 .-- 136 p.

3. Mustafin F.M., Bykov L.I., Gumerov A.G. etc. Field pipelines and equipment: Textbook for universities. - M .: Nedra Publishing House OJSC, 2004. - 662 p.

4. Agapchev V.I., Vinogradov D.A., Fattakhov M.M. Trenchless technologies for the restoration and construction of pipelines. - Ufa: Publishing House of Ural State Technical University, 2005. - 141 p.

Claims (1)

A method of repairing a pipeline by pulling inward pipes, characterized in that protective ends are put on the ends of the pipeline being repaired, made in the form of two coaxial cylinders connected by bases, the case being made of an elastic sheet that is inserted and pressed against the inner surface of the pipeline being repaired, then bent, pressed and fixed to the outer surface of the pipeline being repaired.

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