RU2148697C1 - Wedge-type whipstock - Google Patents

Abstract

FIELD: bore-hole drilling equipment. SUBSTANCE: wedge-type whipstock can be used for enlarging through-bore for tool at cutting out window in producing pipe string, at drilling second bore-hole, and for using subsurface equipment at further operation of well. Wedge-type whipstock has deviating wedge, support, slips with teeth in external surface. Shear bolt contains hinge which is made in the form of half-coupling possessing non-resilient part and resilient part. Non-resilient part of half-coupling is rigidly connected with deviating wedge. Resilient part of half-coupling is located in support body of cylindrical configuration with possibility of swinging motion for half-coupling relative to surface of pin which connects them. Support is made in the form of body of cylindrical configuration and thrusting wedge which is seated in clearance between resilient part of half-coupling and body. Thrusting wedge is secured by shear bolt. Half-coupling is located in upper part of support in body window. Lower resilient part of half-coupling can advance towards wall of casing string through window made in rear part of support body of cylindrical configuration. Slip on internal surface is made in the form of protrusion of trapezoidal configuration. Part of support made in the form of thrusting wedge has slot and its configuration corresponds to that of protrusion. Wedge-type whipstock ensures higher reliability at efficient application in operation due to full guarantee of tight contact between deviating wedge and diametrically opposite walls of casing string, thus allowing for creation of preset angle of cutting by tool for example in cutting out window in producing string. EFFECT: higher efficiency. 5 dwg

Description

 The invention relates to drilling equipment, and in particular to devices for drilling wells and cutting windows in the casing. It can be used to increase the bore for the tool when cutting the window in the production casing, wiring the second barrel and underground equipment during further operation of the well.

 Known diverter [1], including a rock cutting tool, a conical extension, a shaft consisting of two pivotally connected parts between which a retractable stop with a drive is installed, a housing, a retractable stop drive is made in the form of a sleeve mounted on the lower shaft with protrusions on the upper end face for interaction with a retractable stop and with an overlay on the side surface for interaction with the well wall. The lower part of the deflector is deflected due to the overlay, dragging the lower end of the sleeve along with it until the retractable stop and the body are pressed against the wall of the well.

 The disadvantages of the device are: the limited use of the deflecting system by drilling with a chisel and the impossibility of using the window in the production casing and tool when "cutting" the hole when drilling the second shaft due to the absence of a deflector wedge. The presence of the deflecting wedge instead of the shaft (upper) does not provide a tight pressing against the wedge walls of the wedge neither in the upper nor in its lower part due to the possible rotation of the wedge relative to the sliding stop and the formation of a gap between the well wall and the lower part of the wedge. This, in turn, will lead to an increase in the time for milling the window in the casing and to an increase in the metal removal of the wedge during milling, which does not guarantee a predetermined cutting angle.

 Known diverter [2], comprising a tubular body with a deflecting element in its cavity for interaction with a hollow shaft located in the housing, the upper end of which is rigidly connected to the housing, and the lower is mounted on a hinge support. The housing with the diametrically opposite side of the deflecting element is made with a longitudinal slot, the width of which is greater than the shaft diameter, the deflecting element is rigidly connected to the housing, and its working surface is located from the housing at a distance exceeding the gap between the shaft and the housing in the upper part, and the hinge bearing is formed by balls located in the cavity between the housing and the shaft in a plane perpendicular to the axis of the shaft.

 The disadvantage of this device is the unreliability in the case of using a wedge diverter instead of a hollow shaft, because the shaft is curved in the shape of the letter "S", which cannot be used when operating a riber, a mill when cutting a "window" in the casing. The increased flexibility of the deflecting element does not guarantee a predetermined cutoff angle of the side wellbore. Therefore, its function is limited to the work associated with changing the direction of the main trunk of the borehole.

 Known diverter [3], comprising a housing with a groove and a wedge surface, an expansion wedge and a latch installed in the groove of the housing and the wedge, the expansion wedge is spring-loaded relative to the housing, and the latch is made in the form of an elastic rod. The wedge contains a groove, the body is made with a wedge surface and a groove. There is a jumper, pin, spring.

 The disadvantages are: the requirement for sharp braking when landing layout to the face, which can lead to an unplanned cut of the keys and an accident at the bottom; the fixing element does not provide reliable fixation of the wedge in the casing due to the lack of relief on the outer surface, which in turn will lead to the wedge turning during drilling and loss of the orientation of the cut, the presence of a spring, as a structural element, does not guarantee the reliability of the cork fixing on the bottom.

 The closest technical solution to the proposed one is a deflector [4], containing a sub, a drain wedge, a deflector wedge with a groove-shaped surface, a deflector wedge connected with the possibility of radial movement with a support assembly, in the housing of which there are mounted radially extendable ones when interacting with a spacer cone dies with a fixation unit. The deflector is equipped with a spring-loaded pusher, installed with the possibility of interaction of its upper end with the deflector wedge and the associated tail part by means of shear elements with a spacer cone, the deflector wedge in the lower part having a through slot inclined relative to the axis of the deflector, and the support assembly located in the slot finger.

 The disadvantages of the prototype are: the metal consumption of the device, the unreliability of obtaining a given angle of infeed of the second wellbore due to the fact that it does not provide a snug fit of the wedge of the deflector either in the upper or lower part after setting the component to the bottom and the lower part is offset due to the presence of the slot at an angle to the axis of the diverter. In the slot there is a finger that moves with the wedge in the radial direction, but there is no locking element that locks the deflecting wedge after tightly fitting its side surface to the borehole wall. Therefore, the lower part of the deflector wedge can also freely deviate in the opposite direction, forming a gap between the contact surfaces. This in turn will lead to a change in the angle of the hole, increase the time for milling the window in the casing. There is no guarantee of a snug fit and the upper part of the deflecting wedge due to the fact that the stoppers that prevent the upper part of the deflecting wedge from moving are designed to work at the moment the assembly is lowered, while during milling when cutting the “window” the stoppers are cut off between the upper part the wedge and the borehole wall, a gap appears, which leads to an increase in the metal removal of the wedge during milling, increases the milling time, changes the angle of the cut, reducing the reliability of the device in operation.

 An object of the invention is the development of a wedge diverter of increased reliability for effective use in operation due to the guaranteed tight fit of the wedge diverter to the diametrically opposite walls of the casing string, providing a predetermined cutting angle with a tool, for example, a “window” in the production string.

 The technical result is achieved in that the deflector, comprising a housing, a deflector wedge, one of the surfaces of which is made in the form of a gutter, a solid support, a die, a shear bolt, a technological bolt connecting the upper part of the deflector wedge with the lowering elements of the assembly (suspension, riber), a slot with a finger, a die with the possibility of radial movement. It contains a support made in the form of a wedge-shaped pusher, with the extension downward, a deflector wedge rigidly connected to the upper inelastic part of the coupling half by means of a threaded connection, which in turn connects the deflector wedge and the housing with a finger. The housing, the support-pusher and the coupling half located inside the housing are fixed with a shear bolt, the housing has: a window for freedom of action of the hinge, a window for freedom of movement of the lower elastic part of the coupling when it is bent, a window for accommodating the die. The window for the freedom of action of the hinge is made flat at the points of contact with the surface of the coupling half and is located in the upper part of the housing; the window for the freedom of movement of the lower elastic part of the coupling when it is bent is made inside the housing with a smooth surface in 1/2 of the housing. On the surface of the support-pusher there is a guide along which the die and the lower elastic part of the coupling half move.

 In FIG. 1 is a schematic sectional view of a wedge diverter. In FIG. 2 shows a section along AA of FIG. 1; in FIG. 3 shows a section BB of FIG. 1; in FIG. 4 shows a section BB of FIG. 1; in FIG. 5 shows the position of the diverter wedge after the diverter is installed in the face. The wedge deflector contains a housing 1 with windows 2, 3, 4 (Fig. 1 and section AA, B-B and B-C of Fig. 1), a half-coupling with an upper inelastic part 5 and a lower elastic part 6 connected to the housing through the slot 7 with a finger 8 with the housing 1 in the place of pairing - a free fit in the "window" 2 (position AA in Fig. 1). The upper part of the coupling half 5 is connected to the deflecting wedge 9 by means of a thread 10 and fixed by welding. The deflector wedge in the upper part is fixed with a technological bolt to the suspension (not shown). The elastic part of the coupling half 6 is located in the body of the support of a cylindrical shape, the finger connecting the support to the coupling half through the slot in the coupling half is rigidly fixed at the ends of the support, the upper part of the coupling half 5 is connected to the finger with the possibility of swinging movement along the surface of the finger (Fig. 2 - section A -A in Fig. 1). Inside the lower part of the housing 1 there is a support in the form of a spacer wedge 11, the thickness of the upper part of which is equal to the inner radius of the housing 1. The support 11 serves as a pusher and is located between the inner surface of the housing 1 and the lower elastic part 6 of the coupling half. The housing 1, the support 11 and the lower elastic part of the coupling half 6 are connected by a bolt 12. In the housing 1 in the window 4 there is a die 13 with teeth on the outer surface. A trapezoidal protrusion 14 is formed on the inner surface of the die 13, and on the support-pusher 11 there is a guide 15, on the surface of which a groove 16 is made corresponding to the protrusion 14 of the die (section BB of FIG. 1).

Causal relationship
Known technical solutions, the purpose of which is to increase the adherence density of the diverter wedge, solve the problem mainly theoretically, often striving to adhere the wedge to the casing wall with a lateral surface, that is, mainly with the upper part of the diverter wedge, which does not solve the problem to the end. The ideal goal is a snug fit of the deflecting wedge of both the upper and lower parts, but to opposite walls, that is, fit at two points - along the diagonal of the column, at the points of contact with the walls of the well. Comparing the prototype and the proposed deflector, we get a fundamentally new solution, since the swivel connection between the deflector wedge 9 and the support 11 is used using the upper part of the coupling half 5 and the finger 8. The support 11 simultaneously serves as a pusher, as it is made in the form of a wedge, but with a thickness in the upper end part, equal to the inner radius of the housing 1, which allows you to move the deflector wedge and install it with a given cutoff angle due to the rigid connection of the deflector wedge with the upper part of the coupling half 5 and pushing the support-pusher into the housing 1 until it stops, shifting the lower elastic part of the coupling half 6 to the window 2 at an angle providing a snug fit of the deflector wedge above and below without a gap. This technical solution guarantees a tight fit of the die to the casing wall, since the pusher support not only pushes the coupling half out of window 3 and fixes it on the wall, but also due to the presence of an internal groove on the guide surface, which facilitates unhindered movement of the pusher to the stop allows disassociation of the die with the support. The finger connecting the upper part of the coupling half 5 to the housing 1 provides fastening strength and does not allow movement along the slot (as in the prototype) due to the welded connection from the ends and the strength of the material from which the finger is made, the ultimate strength of which must exceed the level of pressure exerted on it both at the time of bending the lower part of the coupling half, and during operation of the diverter on the bottom. The connection of the layout elements is much simpler than that of the prototype, but the technical problem is solved more reliably and more technologically. The device is made in metal, tested and demonstrated industrial applicability.

The wedge diverter works as follows:
The diverter on the drill pipe string (not shown) is lowered into the well to the bottom. Drill string is unloaded (≈P = 2 tons). During unloading, the bolt 12 is connected, which connects the housing 1, the support-pusher 11 and the lower part of the coupling half 6. After the shear of the bolt 12 is cut under axial load, the support-pusher moves up to the stop. When this occurs, the wedge - deflector 9 is displaced to the casing wall in the place of the finger joint due to the occurring elastic deformation of the lower part of the coupling half 6, which bends due to sliding along the guide 15 of the support 11. At the same time, the die 13 from the window 4 moves radially in the groove 16 the protrusion 14 and cuts into the casing wall with teeth (not shown), creating a support for the wedge-deflector 9. The wedge-deflector 9 due to the displacement in the finger connection in the window 2 by the deflection angle, determined by the movement of the support- olkatelya in the body 1, is pressed against the borehole wall on the side opposite the trough. After the support-pusher 11 reaches the stop in the housing 1, the coupling 6 will push out into the window 3 with its lower part and remain there in a state of elastic deformation (Fig. 2). At the same time, the die, moving along the groove 16 with the protrusion 14 along the guide 15 of the support 11, moves in the radial direction by displacing it from the window 4 of the support 11. The die is tightly fixed with its teeth in the wall of the casing, providing pressure of the housing to the production string. A double guarantee of a tight fit of the diverter wedge to the casing walls diagonally relative to the axis of the housing 1 is obtained. Due to the rigid fastening of the diverter wedge 9 with the upper part of the coupling half 5 by means of thread 10 and welding and swiveling with the housing 1, we obtain a flexible layout system controlled by a multifunctional element - a support 11, which is first a pusher and then a fixing element for the lower part of the coupling half, for the die, and for the deflector wedge, moving gradually in the housing 1 to it's time. The upper part of the coupling half 5 has a thread 10 on the inner surface only in the place of contact with the deflector wedge 9, the rest of the surface located in the hinge body 1 does not contain threads, since freedom of movement of the upper part of the coupling half 5 is necessary when the lower part of the coupling half is deflected by the support 11. After fixing the dies and the coupling half with a support in the column wall, a tight clip of both the upper part of the deflecting wedge and the lower one is guaranteed, which is impossible to achieve with the prototype device. The absence of a gap in these places clearly keeps the set cutting angle, reduces the metal removal of the wedge during milling, which in turn provides better work than with the prototype, with less cutting forces. In this regard, the health of the deflector wedge in comparison with the prototype increases.

 In the proposed diverter, the main elements of the layout (support, wedge diverter, coupling half) are made of 40X steel, but Art. 65 G (GOST 14959-79). The coupling half is made integrally, the lower part of which is subjected to special heat treatment to obtain the specified elastic properties. The die is made of U7 steel (GOST 1435-90). The relief of the surface of the die is made by screw thread. The shear bolt is made of steel, designed for shear force. The guide is made by milling on the surface of the support from the side of the die. The finger is made of steel, designed for strength higher than the resulting axial loads on the wedge deflector. The support in the upper part has a thickness equal to the inner radius of the hinge body, providing a reliable fit of the deflecting wedge in the lower part of the coupling with its movement, and guarantees high reliability of fixing the deflecting wedge to the casing walls without a gap in the upper and lower parts of the wedge. The support is made in the form of a spacer wedge with the extended part placed down, and the upper part 2 times narrower than the lower part. The coupling half is located with a gap between the casing and the deflecting wedge, which allows bending to take a free position in the casing window and to be fixed in the casing wall at a predetermined angle of the window casing in the casing. The support, made in the upper part with a smaller size than the inner radius of the housing, does not provide the function of a pusher, but larger than the inner radius of the housing weakens the strength of the coupling half and unnecessarily metal-intensive.

Compared with the prototype, the invention has advantages:
- it is easier to perform layout elements and more technologically advanced in the assembly;
- it has, with fewer layout elements, greater controllability due to the stiffness of the joints of the deflector wedge with the hinge due to the constant loading of the device during transportation to the bottom and the multifunctionality of the deflector support;
- promotes smooth and reliable fastening of the wedge in the upper and lower parts and maintains a trouble-free operation mode;
- it provides increased reliability of the diverter for kicking the window in the casing due to double fastening and tight fit of the diverter wedge at the contact point of the coupling half and the die to the wall of the casing. Due to the presence of a hinge element located between the deflector wedge and the support, its bending forces and reliable fixation by the pusher support, the effect of tight fit of the upper part of the deflector wedge to the opposite side of the casing string is enhanced. As a result of the effective total action of the wedge diverter assembly elements, a significantly more reliable fit, without gaps, of the diverter wedge to the casing walls is ensured. Unlike the prototype, this fit is made diagonally - the top and bottom of the wedge. In the prototype, the deflecting wedge was fitted only along the lateral side in the lower part of the wedge.

List of information taken into account
1. A.S. N 855175, MKI E 21 7/08, dated 10.12.80 (analog).

 2. A.S. N 1469075, MKI E 21 B 7/08, dated April 21, 87 (analogue).

 3. A.S. N 981556, MKI E 21 B 7/08, dated 08/17/79 (analog).

 4. A.S. N 1089224, MKI E 21V 7/08, dated 12/15/81, (prototype).

Claims (1)

 A wedge deflector comprising a deflector wedge, a support, a die with teeth on the outer surface, a shear bolt, characterized in that it comprises a hinge made in the form of a half coupling having an inelastic and elastic part, the inelastic part of the half coupling is rigidly connected to the deflector, and the elastic part of the coupling half is located in the housing of the support of a cylindrical shape with the possibility of rocking motion on the surface of the finger connecting them, and is fixed from longitudinal movements by rigid connection of the ends of the finger with the housing of the support, filled in the form of a cylindrical body and a spacer wedge placed in the gap between the elastic part and the body and secured with a shear bolt, the coupling half is placed in the upper part of the support in the housing window with the ability to move and exit the lower elastic part of the coupling half to the casing wall into the window made in the back of the casing of the support is cylindrical in shape, the die on the inner surface is made in the form of a protrusion of a trapezoidal shape, and on the part of the support made in the form of a spacer wedge, there is a groove corresponding to the shape protrusion.

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