RU2270952C2 - Method of changing large-diameter pipeline without trenching - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: method comprises changing the sections of pipeline by periodic pulling through the new pipeline to the place of the pipeline to be removed. The pipeline to be removed is cut from inside by means of a ring cut, cut longitudinally, and dismounted.

EFFECT: enhanced safety.

1 cl, 2 dwg

Description

The invention relates to construction and can be used for trenchless replacement of sections of underground pipelines of large diameter, in particular when replacing sections of pipelines under roads and railways.

There is a method of preventing accidents in oil and gas pipelines, which consists in the fact that major repairs of the pipeline section are carried out. According to this method, the trench in which the pipeline is located is dug up, the damaged section of the pipeline is removed, a new pipe is laid in its place in the trench, connected to the pipeline, the trench is buried and the adjacent area is restored [1, 2].

This method is very time-consuming, and when replacing sections of pipelines under roads and railways, it stops the transport or construction of a bypass road due to the destruction of the roadbed.

There is also known a method of trenchless replacement of the pipeline without destroying the old one, which consists in simultaneously dragging the old section of the pipeline and the new one welded to it.

The disadvantage of this method is that when dragging a new site to the place of the old one often pulls off the roadway, which leads to a stop of transport or the construction of a bypass road.

A known method of trenchless replacement of the pipeline, which consists in the destruction of the old pipeline while laying a new one. In this method, fragments of the old pipeline are pressed into the surrounding soil mass, compacting it [3, 4].

The disadvantage of this method is the possibility of damage to existing communications by soil pressure during compaction and the need for significant efforts to destroy the old pipeline.

A known method of trenchless replacement of the pipeline, which consists in the destruction of the old pipeline while laying a new one [5]. In this method, the destruction of the pipeline is carried out by dividing into longitudinal strips, and the load for destruction is applied to the new pipeline, and the fragments of the old pipeline are directed inside the new one.

Large diameter pipelines have a large wall thickness (gas pipelines with a diameter of 1200-1400 mm have a wall thickness of 12.5-14.5 mm), which requires considerable effort to destroy it and use complex power plants. In addition, the destructive structural element proposed in the method [5], does not provide reliable destruction of a thick-walled pipeline.

The objective of the invention is the replacement of thick-walled pipelines of large diameter with little effort applied to the replaced pipeline without damaging the existing communications (for example, under roads and railways without destroying the canvas, therefore, without stopping the movement and building a bypass road).

This is achieved by the proposed method of trenchless pipe replacement.

The essence of the invention lies in the fact that the proposed method provides for the gradual removal of the old pipeline with periodic dragging to the place of a remote section of the new pipeline.

Figure 1 and figure 2 presents a diagram of the implementation of this method.

The method of trenchless replacement of the pipeline is as follows.

On the route of a worn-out pipe, for example, along the roadsides of a pipeline crossed by a pipeline, two pits are excavated (not shown in the diagram), pipe sections located in the pits are removed.

The installed pipe 1 with a fixed crown 2 made of a pipe segment of the same diameter as the diameter of the pipe, with teeth 3 larger than the diameter of the replaced pipe, which serves to center and prevent damage to the insulation of the installed pipe, is end-to-end with a replaceable section (Fig. 1).

Inside the replaced pipe 5, an annular cut is made at a certain distance from the edge depending on the composition of the soil, then longitudinal cuts are made and this section 4 is dismantled, and the installed pipeline 1 is moved to the vacant place.

The operations are repeated until the old section of the pipeline is completely replaced with a new one.

Literature

1. GF Egerman and others. Repair of main gas pipelines. M .: Nedra, 1973, p. 107.

2. P.P. Borodavkin and others. The construction of gas and oil pipelines. M .: Nedra, 1987, p. 257, 258.

3. RU 2099624 C1, F 16 L 1/028, 04/28/95.

4. RU 2135874 C1, F 16 L 1/028, 11.19.98.

5. SU 1778424 A1, F 16 L 1/028, 09/06/89.

Claims (2)

1. The method of trenchless replacement of a large-diameter pipeline, which consists in removing the old pipeline with laying a new pipeline, characterized in that the old pipeline is replaced by sections with periodic dragging to the place of the remote section of the new pipeline, for which the old pipeline is cut from the inside with a ring cut, longitudinal cuts are made into the deleted area and it is dismantled. 2. The method according to claim 1, characterized in that to protect the insulating coating of the new pipeline and (or) centering it relative to the old pipeline, a crown is mounted on the new pipeline, the teeth of which are larger than the diameter of the replaced pipeline.

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