SU1518475A1 - Method of drilling in unstable rock zone - Google Patents

Abstract

The invention relates to mining and is intended for drilling vertical and inclined wells. The purpose of the invention is to increase drilling efficiency by ensuring the stability of the borehole walls. The method is carried out by means of concentrically installed inner 1 and outer 2 columns / K / pipes, equipped with crowns 3 and 4 in the lower part. In the case of wear, the 3 K 1 crowns are freely removed from the well. To replace the crown 4, a plastic mass is supplied through the internal cavity K 2, which keeps the borehole walls from collapsing when lifting K 2. The plastic mass is then washed away with liquid, K 2 and then K 1 are lowered at the same time and drilling is continued. 2 Il.

Description

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The invention relates to mining and is intended for drilling vertical and surface wells.

The purpose of the turn is to increase the efficiency of drilling by ensuring the stability of the walls of the wells,

Fig, 1 shows the columns of pipes in. Moment bureshresh; FIG. 2 is the same when lifting an outer column from a well filled with plastic mass;

The method of drilling in zone A of unstable ropiaix rocks is carried out by a drill string consisting of inner 1 and outer 2 chambers, centrically mounted pipe, in the SES section of pipe 1.I. 2 ocHaJneifti crowns 3, and 4, As the crowns 3 wear out, the inner column 1 is freely removed from the well to replace the crowns. In the case of the failure of the crowns 4 of the outer column 2. first, the inner column 1 is removed to the surface, then served in the internal cavity COLON - S 2

UNDER pressure plastic mass 5, for example, clay consistency, commensurate with the density of passable rocks. The outer column 2 is lifted by squeezing the plastic mass 5 into the well with a pressure of shdkoti.

After replacing the core 4, the outer column 2 is lowered into the well with the flow of fluid through the internal cavity, the columns, B, as a result of this, the plug of plastic mass 5 is washed out and the internal column -1 is lowered into the cavity of column 2 and drilling continues,

Formula of the invention

The way to buregsh in the zone of unstable rocks, including the joint rotation of concentrically arranged columns of pipes, equipping them with coronacats, their buildup and lifting for the arcs, so that with increasing efficiency of the storm nor by ensuring the stability of the borehole walls, when the outer colopne tube is lifted, a plastic mass is then simultaneously supplied through its inner cavity into the well under pressure, which is then washed out with liquid, and pushes its shaft through the outer cavity of the outer column azhina

Claims (1)

Claim A method of drilling in an area of unstable rocks, including the joint rotation of concentrically arranged pipe columns equipped with a crown®, their extension and rise to replace the crowns, with the exception that in order to increase the efficiency of drilling for by ensuring the stability of the walls of the well, when lifting the outer pipe string at the same time serves through it. the internal cavity into the well 25 under pressure is a plastic mass, which is then washed away with liquid, feeding it through the internal cavity of the external column when it is lowered into the well. figure 2.