SU1286722A1 - Directional drilling apparatus - Google Patents

Abstract

The invention relates to the field of drilling equipment and is intended for posting curved sections of a well. The purpose of the invention is to increase the operating efficiency in the wellbore with a small zenith angle. To do this, the hole core with a small zenith angle on a shaft 2 rigidly connected with the bit 1 has a concentric cylindrical sleeve 3 installed. each blade 4 is opposite to the direction of the bit 1. Depending on the desired change in the direction of the wellbore (left and right), the device is included in the layout of the bottom of the drill string, which has a section in the drilling process Bends either down or up. This achieves an eccentric arrangement of the device in the wellbore. Parts of the device during drilling do not experience dynamic loads, which leads to high performance and reliability. 2 Il. e cl

Description

N3

00 05

 yo

The invention relates to a drilling technique and can be used to guide the curved portions of a well in a rotational manner.

The purpose of the invention is to increase the operating efficiency in the wellbore with a small zenith angle.

FIG. 1 shows a device for directional drilling of wells in the working position; in fig. 2 shows section A-A in FIG. one.

The device for directional drilling includes a bit 1 rigidly connected to the shaft 2, on which a cylindrical sleeve 3 is mounted concentrically with rotation, having on the outer surface means for changing the direction of drilling, made in the form of two screw blades located one above the other at the ends sleeve 3, and the direction of winding of each blade 4 opposite to the direction of rotation of the bit 1.

The device for directional drilling works as follows.

Depending on the desired change in the direction of the wellbore (left or right), the device is included in the bottom hole assembly, in which, during drilling, the area at the location of the device is bent either down or up. This achieves an eccentric arrangement of the device in the wellbore.

In the first case (in Fig. 2, the dotted line shows the surface of rotation of the screw

five

0

five

0

blades 4) at the beginning of drilling the shaft 2 together with the bit 1 and the sleeve 3 rotate together until the screw blades 4 come into contact with the wellbore on the right side. Upon further rotation of the shaft 2, the sleeve 3 due to the screw blades 4 is wedged in the borehole and its rotation stops. Due to the interaction of the blades 4 with the borehole when moving the device along its axis, the bit 1 destroys the bottom hole mainly from the left side, due to which the well changes its direction to the left side.

In the second case, the helical blades 4 interact with the well bore on the left side and the well bore is deflected to the right side.

Claims (1)

Invention Formula A device for directional drilling of wells, including a bit rigidly connected to the shaft, on which a cylindrical bushing is mounted rotatably, having on the outer surface means for changing the direction of drilling, which means that, in order to increase the efficiency of the wellbore with a small the zenith angle, the cylindrical bushing is mounted concentrically on the shaft, and the means for changing the direction of drilling is made in the form of two screw blades located one below the other at the ends of the bushing and, wherein the direction of winding of each blade opposite to the direction of rotation of the bit.