RU2254433C1 - Well drilling rig - Google Patents

Abstract

FIELD: well drilling equipment, particularly for drilling water, oil and gas wells.

SUBSTANCE: drilling rig includes drilling string located above reamer, borer with body and flushing channel. Centralizer is installed at a distance exceeding half-wave length drilling string flexure during drilling process. Centralizer is made as hinged spring-loaded blades with centering diameter corresponding to well diameter in transport position and to expanded borehole part diameter in working position. Reamer has eccentrically located rock cutting blades. Borer body is made as limiting step and is provided with stabilizing members secured to the body from side of rock-cutting blades.

EFFECT: simplified structure, increased efficiency and operational stability.

2 cl, 1 dwg

Description

The invention relates to drilling equipment, and in particular to devices for expanding a wellbore and can be used for drilling and repairing wells for water, oil and gas.

A device for expanding a wellbore [1], containing an eccentrically placed rock cutting and supporting blades and a restrictive stage.

A disadvantage of the known device is the lack of centering of the device relative to the extended part of the wellbore.

Also known is a drilling tool [2], including an expander with rock cutting blades and a borehole, a drill pipe string with a centralizer.

Known drilling tool provides centering of the tool relative to the extended part of the wellbore.

However, the centralizer control mechanism is mounted on the surface of the well and connected to the centralizer via a pressure hose, which complicates the use of the known tool for drilling and repairing deep wells.

Closest to the claimed invention in technical essence is a device for drilling wells, including a drill pipe with a centralizer, an expander, a borehole with a body and a flushing channel, while the centralizer is mounted on a drill pipe above the expander [3].

A disadvantage of the known device is the lack of reliable centering during the expansion of the wellbore.

The aim of the present invention is to provide a device for drilling a well, which with a simpler design provides efficient and stable operation using the property of the drill pipe string to bend during drilling.

The problem is solved in that in a device for drilling wells, comprising a drill pipe string with a centralizer mounted on a drill pipe string above the expander, a borehole with a body and a flushing channel, the centralizer is installed at a distance greater than the half-wavelength of the bend of the drill pipe string during drilling, and made in the form of articulated, spring-loaded blades, the centering diameter of which in the transport position corresponds to the diameter of the well, and in the working - to the diameter of the expanded part of the well bore, the ripper is made with eccentrically located rock-cutting blades, and the body of the borehole is made in the form of a restrictive stage and is equipped with stabilizing elements fixed to the body from the side of eccentrically placed rock-cutting blades.

In addition, the centralizer is designed as a calibrator and is equipped with calibrating elements fixed to the hinged, spring-loaded centralizer blades.

The invention is illustrated in the drawing.

A device for drilling wells includes a drill pipe string 1 with a centralizer 2, an expander 3 with a drill hole 4 and a drill body 5. The centralizer is mounted on a drill pipe string during drilling, which is determined by calculation. The centralizer 2 is made in the form of articulated spring-loaded blades 6, equipped with calibrating elements 7. The expander 3 is made with eccentrically located rock cutting blades 8.

The body 5 of the bore 4 is equipped with stabilizing elements 9 and serves as a restrictive stage.

On the housing 5 is diametrically opposite the restrictive stage is the flushing channel 10.

In the transport position, the centralizer 2 is fixed by means of a rope 11.

The operation of the device is as follows.

The device is lowered into the well, the trunk of which is to be expanded, until the expander reaches 2 expansion zones, include rotation at increased speeds without supplying the device to the bottom and supply of flushing fluid.

At the same time, annular production is formed in the wellbore due to the flexibility of the drill pipe string and the eccentric arrangement of the rock cutting blades.

Further rotation of the device is carried out with the filing on the annular face at medium speed.

During drilling, during the course of the expander 3, equal to the half-wave length of the bend of the drill string, the centralizer 2 with articulated, spring-loaded blades in the transport position and the restrictive stage of the body 5 of the bore 4 will center the device relative to the diameter of the well to be expanded.

During drilling, as a result of friction against the borehole wall, the rope 10 will undergo a break and, when the centralizer 2 reaches the expanded part of the borehole, the articulated spring-loaded blades 6 will switch to the working position and further drilling with the expansion of the borehole will continue while the device is centered on the extended borehole and calibrated diameter of the extended wellbore. After the expansion process and the final washing of the well are completed, the device is removed from the well, and upon reaching the articulated spring-loaded blades of a narrow part of the wellbore, they are transferred to the transport position.

Sources of information

1. RF patent No. 2179618, cl. E 21 B 7/28, 02.20.2002.

2. USSR author's certificate No. 1250640, cl. E 21 B 7/28, 08/15/86.

3. Kalinin A.G. etc. Drilling of inclined and horizontal wells. Moscow, Nedra, 1997, p.237, fig. 6.15.

Claims (2)

1. A device for drilling wells, including a drill pipe with a centralizer mounted on the drill pipe above the expander, a borehole with a body and a flushing channel, characterized in that the centralizer is installed at a distance greater than the half-wavelength of the bend of the drill pipe string during drilling, and made in the form of articulated, spring-loaded blades, the centering diameter of which in the transport position corresponds to the diameter of the well, and in the working - to the diameter of the expanded part of the wellbore, while the expander is made n with eccentrically located rock-cutting blades, and the body of the borehole is made in the form of a restrictive step and is equipped with stabilizing elements fixed to the body from the side of eccentrically placed rock-cutting blades. 2. The device according to claim 1, characterized in that the centralizer is made as a calibrator and is equipped with calibrating elements fixed to the hinged, spring-loaded blades.