NL8104632A - KICKED JOINT WITH VARIABLE ANGLE FOR TARGETED DRILLING. - Google Patents

Description

813226 / Keijser

Short designation: Kinked variable angle joint for directional drilling.

The Applicants named as inventors: Jean-Paul NGUYEN, Emmanuel LAVAL and André CENDRE.

The invention relates to a device generally referred to as a kinked connection, which is placed between the drill string and a ground motor through which a drill is rotatably driven, which connection makes it possible to change the path of drilling.

In the past, various methods and devices have been proposed for performing directional drilling

According to U.S. Pat. No. 3,365,007, the operation of a suitably directed jet is used to locally destroy the formations and create a cavity to which the drill will be driven. It is easy to understand that such a device is not very accurate because the operation of the beam, and thus the change in direction obtained, will be different depending on the hardness of the geological formations. In addition, it is necessary to use a special drill equipped with a nozzle through which the liquid jet can escape.

According to another known method, for example described in British patent 1,139,908, in US patents 3,593,810, 3,888,319 and 4,040,494, or French patent 2,297,989, a device for changing the direction used to surround a portion of the drill fixture, usually near the drill. This device is provided with fingers which are radially displaceable relative to the axis of the set. By judiciously moving these fingers, which come to rest against the wall of the drilled well, a difference is made in the centering of the centerline of the drill relative to the centerline of the well, and thus a change in the trajectory of the bore.

With such devices, drilling progress is not continuous but is performed in successive steps, between which drilling is stopped to allow movement of the direction change device. This results in significant time losses which increase the cost of a drilling operation.

With the current drilling technique in which a ground motor is applied, it has been proposed to place a kinked connection with a certain angle between the drill string and what is referred to as "drill bit" (the whole consisting of the bit and the ground motor). Thus, whenever one wants to change the path of drilling, it is necessary to bring the entire drill string to the surface to connect a new kinked joint where the angle is selected depending on the desired angle change.

New kinked joints called hinged joints have been proposed. They are of the type mentioned in French Patent 2,175,620. These connections 15 are generally composed of two tubular parts that hinge together and can only have two positions relative to each other. In the first position the two parts of the connections lie in line (the angle of the connection is then zero), while in the second position the two parts of the connection mutually make an angle of a certain value. In the same way as with the kinked joints of the previous type, it is necessary to bring at least one of the parts of the joint to the surface when the desired angle change does not correspond to the angle that the two parts of the joint 25 can form together .

To overcome these drawbacks, devices have been proposed that allow the angle of the joint to be changed without the need to lift it up. A connection controller is disclosed in French Patent Application 2,177,920 and British Patent 1,494,273.

French Patent Application 2,432,079 and also Supplementary Applications 2,453,268 and 2,453,269 disclose a kinked connection consisting of two tubular elements mutually forming an angle variable with remote control.

This angled joint, the angle of which is adjustable from the surface, mainly comprises a first and second tubular element, interconnected, the second element being able to pivot about an axis at an angle to the axis of the first element, means for securing the tubular elements after rotation, and remote control means for stepwise changing the angular difference of the second tubular element relative to the first.

In order to control the rotation of the second tubular element and to prevent premature rotation of the elements of the joint after a change of the mutual difference in angular position, one has to resort to additional locking means.

The present invention more particularly relates to a favorable embodiment of these locking means, with smaller dimensions, and with which thus a kinked connection can be obtained which has a small size.

The manner in which this is reduced according to the invention is defined in the appended claims and will be explained below with reference to the accompanying drawing of an exemplary embodiment.

FIG. 1 is a principle diagram of the variable angle kinked joint;

Fig. 2A and 2B schematically and in section represent the main elements of the kinked connection and the locking means; FIG. 3 shows, in isometric perspective, a portion of the guide groove, and

Fig. 4 shows a deflection of a portion of the guide groove.

Fig. 1 shows again the principle of the kinked connection to which the invention relates.

This connection is composed of two tubular bodies 1 and 2, which are mutually connected by an insert element 2a with center line δ, which is fixedly connected to the body 2. The center line X'X of the upper tubular body 1, the center Line Y'Y of the lower tubular body 2 and the centerline Δ intersect at the same point 0.

The angles (Δ / X'X) and (Δ, ΥΎ) that are formed between 8104632 »ih · <. · - 4 - the axis Δ and the axes X'X respectively. Y'Y have the same value oL, So when the body 2 rotates about the axis Δ, the angle bounded by the axes X'X and Y'Y would change between a maximum value 2 ot (the position of the 5 body 2) and a zero value (the position of the body 2 shown in dotted lines).

Fig. 2A and 2B schematically show the main elements of the joint, i.e. the upper tubular body 1, the lower body 2 and the connecting shaft 20, in the position 10 in which the upper and lower tubular bodies mutually make an angle of zero.

The upper body 1 is attached to the end of a drill rod (not shown) while the lower body 2 is screwed onto the ground motor (not shown).

For the sake of simplicity, each of these tubular bodies is shown as a single piece, but it is understood that they may each consist of multiple interconnected elements to facilitate the manufacture and assembly of the joint.

At the bottom of body 1, a bore 11 is provided with shaft Δ. The bottom side 12 of the body 1 is perpendicular to the axis Δ and its plane passes through the intersection of the axes X'X and Δ

At the top, the body 2 carries an insertion element 2a which is complementary to the bore 11 and whose axis is angular with the axis Y'Y of the body 2. The body 2 has a widening 13, the plane of which is perpendicular to the axis of the insert element 2a in a plane passing through the intersection of the axis Y'Y and of the axis of the element 2a.

The tubular bodies 1 and 2 are held in their insertion position by a stop 14 which absorbs the axial forces exerted on the connection during use. The centering of the element 2a in the bore 11 is accomplished by bearings as schematically indicated at 15, 16 and 17, which allow the two tubular bodies to rotate relative to each other. Sealing rings 18 and 19 provide the seal 8104632> * - 5 - between the two bodies 1 and 2.

Within the tubular bodies 1 and 2, a hollow shaft 20 is arranged coaxially with respect to the element 2a and the bore 11, that is, coaxially with the axis Δ, The shaft 20 and the body 1 are continuously connected to one another. This is achieved by the cooperation of a grooved bore 21 provided in the upper body 1, and complementary grooves 22 arranged on the shaft 20. The latter is further provided with grooves 23 which can co-act with a grooved bore 24 in the lower body 2 when the shaft 20, by the action of a spring 25, is placed in the position shown on the right in Figs. 2A and 2B. In this position, the body 2 and the shaft 20 are rotatably connected.

The shaft 20, which is axially movable within the tubular bodies 1 and 2, carries on the outside a profiled guide groove 28, which cooperates with at least one guide finger 26 which is fixedly connected to the body 2, to do the latter rotate about the centerline Δ when the shaft 20 is moved axially from the position shown on the right in Figures 2A and 2B. This groove 20, which is shown in perspective in Fig. 3, makes it possible to obtain a stepwise rotation of the tubular body 2 about the axis Δ ·

For example, the lower end of the shaft 20 is provided with a control mechanism (not shown) which may be of the type shown in the aforementioned additional applications.

The kinked connection is provided with a locking device, comprising at least one finger 100 radially retractable against the action of a spring 101, which finger is placed in a recess 102 arranged in the shaft 20. A ring 3, which can slide 30 on the shaft 20 and pivotally connected thereto, the finger 100 holds within its cavity when the shaft 20 holds the lower body 2 and the upper body 1 during rotation, i.e. when the shaft 20 is in the position in the right half of Figs. 2A and 28, and also during the relative rotation of the bodies 1 and 2. In this position, the ring 103 is axially fixed relative to the shaft 20 by a ball 104 device which interacts with an 8104632 '- 6 - groove 105 arranged in the ring 103. The ring 103 is also provided with openings 106, the usefulness of which will become apparent.

Grooves 107 are arranged in the body 2, parallel to the center line of the device, and at a mutual distance 5 identical to that of the profiled groove 28.

Next, the operation of the device will be described, assuming that the kinked joint is in the position shown in the right half of Figs. 2A and 2B, where the axes of the tubular bodies coincide and the bore has reached a depth on which one wants to change the direction of drilling.

The shaft 20 is caused to be moved axially downward in FIGS. 2A and 2B against the action of the spring 25.

The finger 26, which was first in position 26a (fig. 4), 15 reaches position 2b. In this position, the grooves 23 in the shaft 20 and 24 in the lower body 2 separate from each other, so that the shaft 20 and the body 2 are no longer rotatably connected to each other.

The axial displacement of the shaft 20 continues and the finger 26 reaches the position 26c, causing a rotation of the body 2 about the center axis Δ by an angle <5; - (where n is an integer), so that the tubular bodies 1 and 2 of the kinked joint then make a mutual angle of between 0 and 2 ot,

At the same time, the end of the ring 103 comes into contact with the fingers 26 which prevent further axial displacement of that ring.

Continued movement of the shaft 20 gives rise to unlocking of the ring 103, allowing the retractable fingers to position themselves opposite the openings 30 106 provided in the ring 103. Under the influence of the springs 101, the fingers 100 emerge from their cavities and penetrate their ends inside the grooves 107 pivotally connecting the shaft 20 and the body 2 to each other. As can be seen from the left half of FIGS. 2A and 2B, the fingers 26 are then in position 2d (FIG. 5).

Then the shaft 20 is only subjected to the action of the spring 25. The shaft 20 is pushed back axially upwards in Figs. 2A and 2B. Due to the cooperation between the fingers 100 and the grooves 107 8104632-7, the finger 26 moves axially from position 26d to position 26e (fig. 4), i.e. without relative rotation between the two tubular bodies 1 and 2.

At that time the ring 103 comes into contact with the extension 108 on the body 1, whereby it is axially retained. The additional displacement of the hollow shaft 20 gives rise to the displacement of the fingers 26 from position 26e to position 2or (fig. 4) and also the penetration of the fingers 100 into their cavities 102 by the presence of an inclined guide surface 111, 10 with the ring 103 locked on the shaft 20. The assembly is then in the position shown in the right half of Figs. 2A and 2B.

A further twisting of the body 2 can then be obtained by repeating the above operations.

Changes can be applied within the scope of the invention. For example, they can use control means to ensure that the shaft 20, after displacement, returns to the starting position.

For this purpose a magnet piece 109 can be used, for example a permanent magnet, attached to the hollow shaft 20, and a blade switch such as that sold by Radiotechnique under the designation R 22. This switch connected to the upper body 1 is connected to an electrical circuit (not shown) and actuation by the magnet 109 indicates that the shaft 20 has performed its entire axial displacement.

In the illustrated embodiment, the retractable fingers 100 are carried by the shaft 20 and the axial grooves 107 are provided on the body 2. It is also possible to provide the axial grooves in the shaft 20 while the retractable fingers are then carried by the lower body 2.

8104632

Claims (4)

An angled variable angle joint with remote control, comprising a first tubular member attached to the end of a drill string and a second tubular member connected to a ground motor through which a drilling tool is rotated 5, which tubular members connected, wherein the axis of the second tubular member can rotate about a pivot axis which is at an acute angle to the axis of the first tubular member, the axis of rotation and the axes of the two tubular members being mutually different * 10 and substantially in each other intersect the same point, with remote control means for changing the angular position of the second element relative to the first as desired by pivoting the axis of the second element about said axis of rotation, and means for securing relative to each other of the tube-shaped elements in a selected relative angular position, the tube being The elements are mounted by a rotary insert connection, the center line of which forms the said rotary axis, and through which passes a connecting axis for these elements, which is movable in those elements while remaining pivotally connected to one of them, which connecting axis has a locking position in which it is also rotatably connected to the second tubular member and from which it can be released by an axial displacement, the connection comprising remote control means for axially displacing said connecting shaft, drive means which correspond to an axial displacement of said shaft from the locking position of the second tubular element about said pivot axis, and aids for pivotally locking the elements of the kinked connection preventing any premature twisting of these elements after a change in the relative angular position, characterized in that said tools for the latches include at least one radially retractable finger, axial grooves, and means by which the retractable finger and axial grooves can cooperate when the connecting shaft has caused the rotation of the second tubular body after it has exited the 8104632 * - 9 - has removed the locking position, maintaining the cooperation between the finger and the grooves until the shaft returns to its locking position. 2. Connection according to claim I, characterized in that the retractable finger is carried by the shaft and the axial grooves are arranged in the lower tubular body. 3. Connection according to claim 1, characterized in that the retractable finger is carried by the lower tubular body and the axial grooves are arranged in the shaft. 10 Connection according to claim 3, characterized in that it is provided with means for detecting the return of the shaft to the locking position. 1 8104632