RU2428544C2 - Built-up structure for pulling through pipelines in wells made by method of horizontal drilling in unstable earth - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: built-up structure for pulling through pipelines in wells made by method of horizontal drilling in unstable earth consists of directing conductor connected with hole reamer via bayonet slots and dowels. In front the hole reamer is connected with a drill string, and behind it is connected with a pipeline through a rotary swivel. Strengthening mounting attachments are welded on bayonet slots to facilitate their durability. The bayonet connection disconnects the hole reamer with the directing conductor at a planned section and pulls the pipeline into the well by driving the drill string to rotation.

EFFECT: trouble-free pipeline pulling through in unstable earth and elimination of additional operations for assembly of devices.

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Description

The invention relates to the field of horizontal directional drilling, in particular to structures for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils.

Known prefabricated design for pipe laying, consisting of a pneumatic shock installation located in the pit, pipe and headband mounted on the front of the pipe. (Prospectus of the Horizon construction company, Trenchless technologies for the construction of engineering communications, Odintsovo, 2004) [1].

The main disadvantage of the known prefabricated design is that the laying of the pipeline can only be carried out on a limited horizontal section due to high loads.

The closest in technical essence and the achieved result to the claimed prefabricated structure is a prefabricated structure used in the traditional pipeline pulling scheme, including a drill string (flushing rods), expander, swivel and pipeline. (Construction of underwater crossings of gas and oil pipelines by the method of horizontal directional drilling, O.N. Blagov, G.G. Vasilyev, Yu.A. Goryainov, I.N. Ivanova, A.S. Kechaev, Yu.E. Kintsler, M., Lori, 2003, p. 174) [2].

Its main drawback is the possible collapse of the wellbore between the expander and the pipeline in the presence of unstable soils (the presence of quicksand gravel), since the drilling fluid used to secure the wellbore does not always ensure the wellbore safety, which leads to emergency situations.

The objective of the present invention is to safely pull the pipeline in unstable soils.

The essence of the present invention lies in the fact that the inventive prefabricated structure for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils, including a drill string, reamer, swivel and pipe, according to the invention, is additionally equipped with a removable guide conductor having bayonet grooves smooth-running rollers, reciprocal spikes for bayonet grooves mounted on the expander.

Figure 1 shows a diagram of the inventive prefabricated structure for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils.

Figure 2 shows the location of the guide rollers on the conductor of the inventive prefabricated structure for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils.

Figure 3 shows the shape of the bayonet grooves mating with mating spikes on the expander of the inventive prefabricated design for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils.

The inventive prefabricated design for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils includes a guide conductor 5 connected through bayonet grooves 9 and: studs 3 with a spreader 2, which is fastened in front with a drill string 1 and behind through a swivel 6 connected to the pipeline 7. The strength of the bayonet grooves 9 is ensured by reinforcing nozzles 4 welded onto them from above, and the pipeline 7 is smooth when it is pulled through the guide conductor 5 guide rollers 8.

The inventive prefabricated design for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils, works as follows.

After assembling the structure according to the scheme (Fig. 1) using the horizontal drilling unit through the drill string 1, the assembled assembly is pulled into the previously made wellbore without rotation of the drill string. At the same time, the extender 2 compacts the existing shaft, and the guide conductor 5 prevents the unstable soils from closing behind the expander 2. Fixing the guide conductor 5 on the expander 2 through the bayonet connection (bayonet grooves 9 and studs 3) allows disengagement of the drill string 1 by means of horizontal drilling expander 2 with guide conductor 5 on the planned site due to the shape of the bayonet grooves 9 and the spring properties of the drill string 1 and pull the pipeline into important. The reinforcing nozzle 4 provides the strength of the bayonet grooves 9. The bayonet grooves 9 have recesses B that prevent the reamer 2 from accidentally disconnecting with the guide conductor 5 when dragging the drill string 1 without rotation, and also have slanting grooves B, which, when turning on the drill string 1, ensure guaranteed uncoupling of the expander 2 with the guide conductor 5. The pipe 7 is connected to the drill string through the swivel 6. Further pulling the pipe 7 is carried out through the guides p faces 8 of the guide jig 5 and formed wellbore.

Claims (1)

A prefabricated structure for pulling pipelines in wells made by the method of horizontal directional drilling in unstable soils, including a drill string, reamer, swivel and pipeline, characterized in that it is additionally equipped with a removable guide conductor having bayonet grooves, smooth rollers, response spikes to bayonet grooves mounted on the expander.

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