Method of repair of pipeline with insulation coating

FIELD: machine building.

SUBSTANCE: proposed method comprises contactless unearthing, removing damaged coating, pipe surface processing, applying new coating and burying repaired pipeline. Pipeline separate equal-length sections are unearthed while all process job time intervals are equal. Said removing damaged coating, pipe surface processing, and applying new coating are executed without contact between process equipment and pipeline surface and spark-forming mechanical contact of work tools.

EFFECT: repair without interrupting transfer of product, reduced repair interval.

1 dwg

 

The present invention relates to the field of pipeline construction and the execution of works on repair of the insulation coating on pipelines for various purposes, and can be applied to other process operations, such as insulation of welded joints, operations, quality control, etc.

Known methods of repair of pipelines (Rules of work with the repair of gas pipelines VSN 51-1-97, Moscow, 1997, section 3, p.13-20, more. 2)in which the work is carried out on the pipeline after its shutdown, blowdown, installation parallel (bypass) pipeline with a violation of the provisions of its location.

The main disadvantages of these methods are significant and estimate the costs of stopping the transportation of the product, construction site temporary piping, long term repair work. When performing work on the replacement of insulation used machines based on the pipeline that have scroobious tools (brushes, scrapers, ignorez) (Catalog of machines for the construction of pipelines. Eighth edition, Appoligized of the Moscow regional Council, 1990, p.61-70).

The closest in technical essence to the solution which is claimed, is a way to overhaul the master of the high gas pipeline replacement insulation coating (Rules of work with the repair of gas pipelines VSN 51-1-97, Moscow, 1997, more. 2, section III. p.60-65), which includes disclosure of the pipeline, the rise of the pipeline, clearing of old insulation, surface preparation and application of a new coating, pipe laying and backfilling.

This technical solution is adopted for the prototype.

The main disadvantages of this solution are the need off, blowing the repaired piping, installation of parallel (bypass) of the pipeline, the violation of the provisions of its location, the additional load of the pipeline during its ascent, which requires additional state of stress control tubes, the inability to apply in the winter insulating materials, which require positive temperature metal pipes.

All the above requires considerable time and money when performing repair work.

The task of the invention is to provide a method of repair of insulation coating without stopping the transportation of it product (gas, oil etc) and reducing time to repair.

This technical result is achieved in that in the method of repair of insulated coating of the pipeline, which includes contactless with pipe excavating the pipeline, removing damaged insulation coating, surface preparation pipeline the od of the application of the new insulation, the application of new coating, and the instillation of the repaired pipeline, which is characterized by the fact that excavating the pipeline carry out individual sections, each of the sections has the same length, and each technological operation - the same time, removing the damaged insulation coating, surface preparation of the pipeline under the application of the new insulation, the application of new coating, performed without contact equipment surface of the pipeline and sparkle-forming mechanical contact of the working tools.

Since the unearthing of the pipeline perform consistently, separate equal parts, and cleaning, preparation for application of the new insulation and the application of new coating, perform process sequentially on each plot, and the total length of the plots corresponds to the conditions, which ensure equality of time of completion of surface preparation for the application of new coating, on the last section with the end of time gaining the strength of a new coating on the first segment.

Repair of insulated coating of the pipeline in areas of residual ground poles is performed in the above sequence. Figure 1 shows a diagram of the sequence you is filling up works by way of repair of insulated coating of the pipeline, which is claimed.

The process of performing major repairs individual local areas MG is carried out with a pressure drop not less than 10% of the maximum working pressure for the last year of operation that meets the requirements of the standard documentation on safety.

The peculiarity of this method is the use of equipment that does not create stress on the pipe surface and has no sparkle-forming mechanical contact working tools when cleaning, surface preparation and pipework.

First, it performs excavation work on the disclosure section of the pipeline and the formation of the trench with the use of excavator and bulldozer equipment, provided the proximity of the cutting edges at a distance not closer than 0.5 m to the generatrix of the pipe on all sides. The spoil is removed by hand kapisanan at a distance of not less than 0.1 m of the pipe without the use of percussion instruments, and the final purification is fire resistant, for example, water-jet tool.

Earthworks are carried out by separate sections. Length of the plot is determined for each pipe provided to prevent plastic deformation of the tube as a two-way fixed-fixed beams, takes into account the dependence on the diameter of the pipe, the thickness is in the walls, the type of soils, the pressure of the product in the pipe and other parameters.

Between two adjacent pits remains unpaved bearing 1.

A sequential workflow is caused by the need for "hard" save the previous position of the pipeline and to completely eliminate the appearance of additional longitudinal-transverse stresses in the body of the pipe.

In connection with the prohibition of processing the surface of the existing pipeline equipment with sparkle-forming mechanical contact working tools, as well as the mechanical load on the pipe surface, the one possible means of surface preparation methods are using intrinsically safe technology (see information technology monthly Ukraine "Market instalacji", No. 2, 2000, p.18-19).

The operation is removal of the old coating by using intrinsically safe, for example, high-pressure manual water jet equipment 2, which may be a mobile unit (crane, pipelayer), equipped with a boom on which you installed the pump unit ("WOMA", Germany) with a feed hose and the work nozzle, mounted on the boom.

After the process of removing the old insulation on the first separate area and it begins the process of surface preparation is of Truboprovod under the application of a new coating, for example, vodoistochnaya processing 3 equipment, which may be a mobile unit (crane, pipelayer), equipped with a boom that has sandblasting (DSK-250 Russia) with the feed hose and the work nozzle, mounted on the shaft, and removing the old insulation perform in the next section.

After completion of surface preparation on the first separate area and it begins the process of applying the new coating of the pipeline 4 equipment, which may be a mobile unit (crane, pipelayer), equipped with a boom that has installation airless coating ("WIWA" Germany) or similar to the supply hose and the work nozzle, mounted on the boom.

The second section begins the process of preparing the surface of the pipeline under the application of new coating, and removing the old insulation perform in the next section.

Special attention should be paid to the materials and equipment for applying the new coating. The perform insulation work on active pipeline and General operating conditions of the pipeline, at the present time, cause application of insulating materials, which can be applied without contactor is affected with pipe insulation machines which create mechanical stress on the surface of the pipeline. This is, basically, polyurethane coatings, such as "Protegol UR-Coating 32-55", "Copon Hycote 165-Varplex", "polyurethane coating T.U.", etc. that can be applied by airless application.

After completion of the process of applying a new coating of the pipeline on the first separate area and it begins the process of gaining strength (polymerization) of the new coating, the second part is applying a new coating of the pipeline, the third section begins the process of preparing the surface of the pipeline under the application of new coating, and removing the old insulation perform on the last section. To save the General rhythm of the technological process, prevent downtime, and as a result, to save time and money is important and necessary so that the total length of individual sections was calculated depending on the time of gaining new strength of the coating, while the work is finished surface preparation for the application of new coating, on the last section coincided with the end of time gaining the strength of a new coating on the first segment. Subsequently the tamping of the soil under the pipe and complete the backfilling of the trench 5 with the layer-by-layer filling of the soil and its seal. Repair of insulated coating of the pipeline in areas of residual g is antovich supports is performed in the above sequence. Finally run earthwork reclamation works, relocation of equipment to the next prepared the sections and the order of technological operations is repeated.

Thus, the proposed solution provides a repair coating without stopping the transportation of it product (gas, oil etc) and reducing time to repair.

Repair works on the active pipe determines the ability of doing work in the winter period due to the positive surface temperature of the pipe, the heated product, which is exported.

The proposed solution is embodied in the overhaul of MG "Vasevichi Valley III thread"MG "Yelets-Kremenchuk-Kryvyi Rih.

The method of repair of insulated coating of the pipeline, which includes contactless with pipe excavating the pipeline, removing damaged insulation coating, surface preparation of the pipeline under the application of the new insulation, the application of new coating, and the instillation of the repaired pipeline, characterized in that the digging of the pipeline carry out individual sections, each of the sections has the same length, and each process step is the same time, removed the e damaged insulation coating, surface preparation of the pipeline under the application of the new insulation, the application of new coating, performed without contact equipment surface of the pipeline and sparkle-forming mechanical contact of the working tools.



 

Same patents:

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2 ex

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EFFECT: wider range of technical means.

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