MX2014006226A

MX2014006226A - Rotatable and bendable casing connection.

Info

Publication number: MX2014006226A
Application number: MX2014006226A
Authority: MX
Inventors: Brian K Klimack
Original assignee: Klimack Holdings Inc
Priority date: 2011-11-25
Filing date: 2012-11-23
Publication date: 2014-07-11
Also published as: WO2013075228A1; AR088958A1; MX349423B; CO6960520A2

Abstract

The present invention provides a casing connection device allowing both bending and rotating motion and that provides three separate sealing areas for leak prevention.

Description

CONNECTION OF ROTATING AND FLEXIBLE COVERING PIPE FIELD OF THE INVENTION The present invention relates to a flexible and rotary casing connection for use in well bottom drilling.

BACKGROUND OF THE INVENTION In oil and gas wells, when the casing is subjected to a downward movement of the hole, failures in the casing or in the casing connection may occur. The movement of the casing can be caused by many factors such as displacement formations, formation pressures, overload pressures, and thermal expansion and contraction of steam injection operations. The stresses induced to the casing coming from factors such as these can buckle the wall of the casing or cause the connections to separate or leak. In some cases, the casing is cemented in the well bore, however, movements have still been observed and faults still occur. In other cases, where the casing is in an open hole without cement, the movement of the lining of the casing pipe is often even more serious. Therefore, it has since the movement from the thermal expansion affects both cemented and uncemented lining pipes.

The fluids and sands produced from the formations tend to create empty spaces in the formation and result in decreases in formation pressure. This often results in higher overload pressures collapsing the formations lower, causing additional movement of the formation. When the lining pipes reside in these empty formations, they undergo several loads of the formations and are forced to move with the formations. All movement restrictions due to the rigidity of the casing can cause buckling or separation of the casing. Casing pipes are more likely to fail in their threaded connections, which are usually the weakest link in the casing string.

The casing that is subjected to thermal expansion and contraction of the steam injection often goes through larger movements than those generated by the movements of the formation. When a casing is cemented in the well, it is held rigidly in the formation. The thermal expansion of the steel casing pipe, even when it is cemented, it is difficult to eliminate. The casing tends to contract or expand in the cement and cause damage to the casing, damage to the cement joints and even damage to the formations. In the case of a casing in an open hole, especially in unconsolidated formations such as tar sands, the formation often shakes or collapses around the casing. Although these linings are not cemented, the sands collected around the casing pipes can keep the casing in a rigid state like cement. Since these casing pipes are in open holes, they are subject to more movement of the formation than those that are cemented. The thermal loads experienced by the casing pipes eventually damage them. The drilling of horizontal wells is increasingly a popular method of oil and gas production from formations. Some of these horizontal wells have a shallow vertical depth, and require high-grade construction angles to hit the target. The casing connections have had to be redesigned in order to handle the strong dog-leg folds of the drilling and place the casing in the well without bending failures.

When there is a failure of the casing in a well drilling, often the well is lost. A series of scenarios have commonly been observed. Failure of a cemented casing to the surface can often lead to forming pressures or fluids that migrate to the surface without having any well control. Cladding pipes cemented to the surface that have been corrugated over time can damage the finishing equipment, and decrease the size of the casing inlet to deploy standard-sized equipment. A failure to produce a casing in open holes can also result in a loss of wells. In a situation where the sand control linings are in place and fail due to movement or connection failures, the sand control functions of that liner can be lost. Sand production can make a well uneconomical to operate. A tight or wavy sand control liner can eliminate the passage of other pipes or equipment through the liner, resulting in loss of production or loss of the well. Movement of the production liner that hangs from the bottom of an intermediate string can apply lateral loads to line hangers and packers, causing them to leak. When the Cement joints are damaged in a cemented casing, unwanted communication can occur between formations and between the casing and the formation. When a rigid casing string passes through a construction section of a horizontal well, often the casing is not able to pass through it, or the casing connections are damaged due to bending.

All casing connections can withstand flexing to some degree, but in most cases, the connection will leak or separate when flexed. Most connections are based on the threads to produce a seal, as well as the torque and tensile strength of the connection. Once the thread has a bending load applied, the integrity of the connection is drastically reduced or completely lost.

Therefore, it is desirable to develop a casing connection that can allow bending and rotation of the casing pipe during installation and operation. Furthermore, it is desirable to provide flexibility to the rigid, standard casing, so that it can be deployed in dogfold-like, more closed, or flexed bends, without the use of angled drilling equipment.

BRIEF DESCRIPTION OF THE INVENTION Therefore, the present invention provides a cladding connection device that permits both flexion and rotation movement and provides three separate sealing areas for leak prevention.

BRIEF DESCRIPTION OF THE FIGURES The present invention will now be described in more detail with reference to the following figures in which: Figure 1 depicts an embodiment of the substitute attachment portion of the top face of the present casing connection; Figure 2 depicts an embodiment of the substitute attachment portion of the underside of the present casing connection; Figure 3 depicts one embodiment of a threaded coupling for use in the present casing connection; Y Figure 4 depicts one embodiment of an assembled liner pipe connection of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a casing connection that can allow bending and also bending under rotation. Such connection must constructed in a manner that is equal to or exceeds the standard connection specifications, so you can replace standard connections or work in conjunction with them. The present connection allows the bending of any lateral loads, to allow the movement of the casing without connection error. The present connection also allows for flexing in the connection, while the casing is rotated. This allows rigid casing strings to pass through closed, dog-leg type folds in the well. When a well is drilled, the location and degree of bending of each dog-leg fold is known from the drill information. Accordingly, the present connection can be established along a length of casing to align with the dog-foot-like folds of the bottom of the well, when the casing is in its final resting position or depth.

The present connection preferably takes into account controlled degrees of bending, as well as the establishment of loads to allow bending to occur. The present connection more preferably acts to seal the pressure, withstand the applied torsional stress, the compression and the tensile loads when the casing passes into the well. This must also seal the pressure, while loads are applied to the connection during the production phase of the well. These loads would be applied from the thermal applications, and the movements of the formation.

In a further embodiment, the present connection allows the rigid, standard cladding pipe to be deployed in dog-leg folds, more closed or flexed, in the construction section than is typically possible. For example, the present connection may allow the rigid, standard casing to be deployed in flexures of up to 15 ° compared to a typical 7o dog-fold type limit. This allows the formation of constructions through shallow vertical depths, without the help of inclined drilling equipment.

Typical connections in the art consist of a spigot and box connection consisting of a male tang end and a female box end. The end of the box can be of two styles, the first of which is a coupling connection. The coupling is a short x / o substitute joint with two box ends on it. The coupling is connected to the shank end of the casing and the other end of the casing is also a shank end. Once the coupling is connected to the joint, the joint now becomes a spigot and box x joint. In the second style, The end of the box is machined directly to the body of the casing gasket as a flush connection. The flush connections are often weaker due to the smaller cross-sectional area of material at the end of the box, as compared to a coupling cross-sectional area. The coupling joint has a larger outside diameter than the flush joint at the ends of the joint box. Coupling connections are usually stronger than flush connections, since they are made of more material. In some connections, the coupling connection provides a better seal than some flush connections.

Typical thread types used in either a coupling or flush connection may vary. There are several different thread profiles on the market, each offering a certain quality. The quality varies to offer better torque capacities, traction, compression, bending, and sealing. All connections are based on threaded profiles to provide these qualities.

On the contrary, the present connection does not depend on the type of thread to provide resistance to sealing, torsional stress and compression. Instead, the thread is used only to control the maximum tensile load.

The new connection is not based on a threaded profile to provide its sealing, torsional, compression, or bending qualities. It will be based on the threads, just for its traction load.

The new connection will consist of three main components: a substitute union of superior face, a substitute union of inferior face and a collar of adjustment.

A preferred embodiment of the upper face substitute joint 2 is shown in Figure 1. The upper face substitute joint 2 includes an inner bore diameter that is preferably consistent with the nominal inside diameter of the liner pipe to be used. with her. An outer surface of the upper face substitute joint 2 includes a first face of the circular radius 4 for coupling with an internal face of the adjusting collar. The upper face substitute joint 2 further has a first flat end 6 which can preferably be machined, welded or threaded to match the casing with which it will pass. Most preferably, the first flat end 6 is threaded. A second face of the circular radius 9 is provided with one or more means for preventing torsional stress, preferably in the form of knurling with torsional wheel teeth 8 along an outer surface of the second face of the circular radius 9.

A preferred embodiment of the substitute union of The lower face 10 is shown in Figure 2. The lower face substitute joint 10 includes an inner bore diameter to match the nominal inside diameter of the casing to be used with it. An outer surface of the lower face replacement joint 10 preferably has a threaded portion 12 for engaging and screwing into the adjustment collar. The lower face substitute joint 10 further includes a third face of the machined circular radius 14, having one or more means for preventing torsional stress, preferably in the form of knurled torque wheel teeth 16 to an outer surface of the third face of the circular radius 14. The lower face substitute junction 10 engages the upper face substitute junction 2 by bringing together the second face of the circular radius 9 and the associated torque wheel teeth 8 with the third face of the circular radius 14 and the associated torque wheel teeth 16 in such a manner that sets of torque wheel teeth 8, 16 are engaged. The lower face substitute joint 10 further has a second flat end 18. The second flat end 18 can preferably be machined, welded or threaded to match the casing pipe with which it will pass. Most preferably, the second flat end 18 is threaded.

One embodiment of the adjustment collar 20 is shown in Figure 3. The adjustment collar 20 has an inner bore diameter in which an upper portion of the inner diameter is larger than the outer diameter of the first flat end 6 of the substitute connection upper face 2. A central portion of the inner diameter of the adjusting collar 20 preferably consists of a fourth face of the machined circular radius 22, which will engage the first face of the circular radius 4 of the upper face substitute attachment 2. A lower portion of the inner diameter includes a threaded connection 24, which engages the threaded portion 12 of the lower face substitute junction 10. In a preferred embodiment, the threaded connection 24 of the adjusting collar 20 is a female threaded connection and the threaded portion 12 of the lower face substitute joint 10 is a male threaded connection. The outer diameter of the adjusting collar 20 preferably resembles the coupling of the casing used. The adjustment collar 20 may optionally contain one or more fastening screws (not shown) to insure against any additional movement or kinking to the connection after the initial screwing.

The present connection can be assembled before it passes into the bottom of the well along with the casing pipes. One mode of the assembled connection of the present invention is shown in Figure 4. To assemble the connection, the adjusting collar 20 first slides over the portion of the first flat end 6 of the upper face substitute joint 2. The upper face substitute joint 2 is then placed with the lower face substitute junction 10, in such a way that their faces of the circular coupling radius 9, 14 and the torsion wheel teeth 8, 16 are coupled to each other. The adjusting collar 20 is then lowered until the threaded connection 24 of the adjusting collar 20 engages with the threaded portion 12 of the lower face replacement junction 10. The adjusting collar 20 is then rotated to engage the threaded connection 24 with the threaded portion 12 of the lower face replacement junction 10. The rotation acts to tighten the adjusting collar 20 until the fourth inner face of the circular radius 22 of the adjusting collar 20 engages the first circular face 4 of the joint Substitute of upper face 2.

A dust seal 28 and O-ring 26 can be added between the adjusting collar 20 and the upper face substitute junction 2 at the contact point of the first and fourth faces of the circular radius 4, 22, to prevent entry of sand in the connection and potentially the connection is spent.

An optional additional ring "O" can be inserted into each pair of faces of the circular radius 4, 22 and 9, 14 to provide an additional seal.

The amount of torque applied to the threaded connections 12, 24 will determine the amount of force required to flex or rotate the upper and lower face replacement junctions 2, 10 away from one another along their circular radius faces. coupling 9, 14 and 4, 22. The amount of force required can be predetermined and established before passing the connection to the downhole, by the degree of tightening applied to the threaded connections 12, 24. One or more means of preventing torsional stress, preferably in the form of coupling torque wheel teeth 8, 16 act to prevent excess twisting or unscrewing of the connection during rotation and bending at the bottom of the well. Optionally, any number of means known in the art can also be used to prevent against excessive torque, or loosening of the connections, including, without restriction, the set screws or the welding points.

After the present connection is assembled, it is attached to the casing that will be used. The present connection provides three separate sealing areas. The first sealing area consists of the seal created by the upper face substitute joint 2 and the faces of the circular radius 9, 14 of the lower face 10 substitute joint. sealing area consists of the seal created by the upper face substitute joint 2 and the circular radius faces 4, 22 of the adjustment collar 20. Finally, the third sealing area consists of the seal created by the adjustment collar 20 and the connections threaded 12, 24 of the lower face substitute junction 10. In the present connection, a leak path from the annular space of the well to the interior of the casing or vice versa can only develop if two of the three sealing areas fail. That is, a failure of a combination of the faces of the circular radius faces 9, 14, the faces of the circular radius 4, 22, or the faces of the circular radius 9, 14 together with the threaded connections 12, 24 would be required to cause A leak. Typical casing connections only have a sealing area, the threaded connection and the flexing of this threaded connection most commonly contribute to the formation of a leak path in the known casing connections.

When the casing pipe and the present connections are passed in the well, to the bottom of the well, they will find dog-leg type folds located in the well, as a result of the drilling. As the casing is passed through these dog paw-like folds, the rigidity of the casing can cause the casing to become stuck within the dog-leg fold. In such cases, the This connection allows some bending when induced with bending forces, allowing the casing to better fit the direction of the bends in the well. If the casing has to be rotated through these bends, the present connection can be rotated at the same time that it is flexed to fit the well bore. If the depths or location of the dog leg-type bends are predetermined, the present connections can be placed in predetermined lengths along the length of the casing string corresponding to the depths or the locations of the dog-leg type folds. . This reduces the amount of tension in the same lengths of the casing after the casing has been installed.

In wells where thermal expansion and contraction is evident, the present connection can absorb some of these thermal loads that would otherwise be placed in the threaded portion of typical connections. The majority of the thermal movement observed in the casing is found in the open hole sections of the wells, where the casing is allowed to move more freely. In many of these open holes, sand production, fluid production, and formation movements are evident. As spaces are created from the solids and fluids displaced, the formations will change and create the unwanted movement of the casing.

The movement of a casing in the open hole also affects the forces acting on the casing lining hangers. Most wells will produce closer to the well's heel than at its tip. Most training movements are noticed in the heel as well. The increase in the movement of the casing in the bead area tends to compensate for the position of the hanger of the lining of the casing with respect to the intermediate casing cemented by causing a bending load. This typically results in a seal failure. By placing the present connection directly after the lining hanger and through the heel area, bending movements are absorbed, placing less stress on the casing liner hanger and casing connections in the bead area .

In the thermal wells where the intermediate casing is cemented to the surface, unwanted loads have also been observed in the casing. In the cemented wells, the casing acts on the expansion tensions and thermal contraction, but it is prevented from moving by cement adhesion. Since the intermediate casing typically passes through the construction section of the well, any casing connections used in this section are already under the bending stress through the construction section and thermal expansion or contraction. they add to this tension. The result is often failures of sealing the connection and collapse of the casing. By placing the present connections in predetermined areas of the cemented intermediate casing, bending is allowed, and the stresses of the construction section and the thermal movement can be absorbed, thus protecting faults from the pipe bodies of coating and the connections of the casing.

The present connections can also be used in different applications such as mining or salt production caverns or any circumstance where the casing is subjected to bending for any number of reasons.

The present connection can optionally be fabricated directly on the flat end cladding pipes and used as a total connection of the cladding pipe, or it can be assembled to the cladding pipes. existing threaded casing pipes and placed specifically along the casing string as required.

There are no elastomeric elements used for sealing in the present connection. All seals are preferably made of metal, and more preferably made of steel, and therefore can withstand extreme temperatures and pressures.

In the above specification, the invention has been described with a specific embodiment thereof; however, it will be apparent that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention.

Claims

1. Casing connection device that allows both flexion and rotational movement and provides three separate sealing areas for leak prevention.

2. Liner pipe connection according to claim 1, characterized in that it also comprises a substitute upper face connection, a lower face substitute joint and an adjusting collar.

3. Casing connection according to claim 2, characterized in that the upper face substitute joint comprises a first flat end for coupling with a casing section, a first face of the circular radius for connecting with the adjusting collar and a second face of the circular radius comprising one or more means for preventing torsional stress.

4. Casing connection according to claim 3, characterized in that the lower face substitute joint comprises a second flat end for coupling with a section of casing pipe, a third face of the circular radius for connecting with the upper face substitute connection. and one or more torque prevention means.

5. Connection of casing pipe according to claim 3, characterized in that the adjustment collar comprises an inner bore diameter with an upper portion for connecting with the upper face substitute connection, a lower portion for connecting with the lower face substitute connection.

6. Liner pipe connection according to claim 5, characterized in that the inner bore diameter of the adjusting collar comprises a central portion having a fourth face of the circular radius for coupling to the first face of the circular radius of the face replacement joint higher.

7. Liner pipe connection according to claim 5, characterized in that the lower portion of the inner bore diameter of the adjusting collar is machined with a threaded connection to engage a threaded outer surface of the lower face substitute joint.

8. Liner pipe connection according to claim 3, characterized in that the first flat end of the upper face substitute joint has a finish that is selected from the group consisting of machining, welding and threading to match the pipe section of the pipe. coating.

9. Coating pipe connection according to claim 8, characterized in that the first flat end is threaded.

10. Casing connection according to claim 3, characterized in that one or more torsional stress prevention means are knurled torque wheel teeth along an outer surface of the first face of the circular radius.

11. Liner pipe connection according to claim 4, characterized in that the second flat end of the lower face substitute joint has a finish that is selected from the group consisting of machining, welding and threading to match the pipe section of the pipe. coating.

12. Casing connection according to claim 11, characterized in that the second flat end is threaded.

13. Casing connection according to claim 4, characterized in that one or more torsional stress preventing means are knurled torque wheel teeth along an outer surface of the third face of the circular radius.

14. Casing connection according to claim 13, characterized in that the second face of the circular radius and the third face of the circular radius are engaged in such a way that their torsional wheel teeth engage.

15. Liner pipe connection according to claim 7, characterized in that the threaded connection of the adjusting collar is a female threaded connection and the threaded surface of the lower face substitute connection is a male threaded connection.

16. Casing connection according to claim 5, characterized in that the adjusting collar comprises one or more fixing screws for securing against rotational movement of the casing connection.

17. Casing connection according to claim 14, characterized in that a first sealing area comprises the coupling of the first face of the circular radius and the fourth face of the circular radius, a second sealing area comprises the coupling of the second face of the The circular radius and the third face of the circular radius and a third sealing area comprises the coupling of the threaded connection of the adjusting collar and the threaded connections of the lower face replacement joint.

18. A casing connection according to claim 14, characterized in that it also comprises a seal against dust and an O-ring inserted between the adjusting collar and the sub-face connection at the contact point of the first face of the casing. circular radius and the fourth face of the circular radius, to prevent sand from entering the casing connection.

19. The casing connection according to claim 1, characterized in that the casing connection is used to connect standard casing for deployment in dog leg type bends having bending angles of up to 15 °.