Releasable headstall

Abstract

The releasable headstall comprises a cable connector, a working barrel and an instrument connector which are sequentially arranged from top to bottom, the inner diameter of the working barrel is large in the upper portion and small in the lower portion, transition is achieved through a circular bead, and sheet type weaknesses are arranged on the circular bead; the lower end of the cable connector is connected with the upper end of the working barrel; a through core penetrating hole is formed in the center of the instrument connector, the hole wall of the core penetrating hole extends upwards and penetrates through the sheet-type weak point, the hole wall of the core penetrating hole is connected with an inner fishing cap above the sheet-type weak point, the lower end face of the inner fishing cap can make contact with the upper end face of the sheet-type weak point, and the maximum outer diameter of the inner fishing cap is smaller than the lower small inner diameter of the working barrel. According to the headstall, the problem that an instrument is stuck in the well testing process is solved, the headstall can be rapidly and safely released, a logging cable and a core penetrating wire can be always located on the central axis when the logging cable and the core penetrating wire are installed, a side wire leading device is not needed, manufacturing cost is reduced, assembling time is saved, and using efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of underground testing, in particular to a releasable bridle. Background Art

[0002] Well logging operations are performed within oil, gas, or water wellbores. Powered by a testing vehicle, instruments are lowered via cables into the tubing or casing, testing downhole data. Long-term production in oil, gas, or water wells can cause instrument jams due to engineering, geological, and construction issues. Unjamming presents safety risks, damage to instruments and cables, and labor costs associated with unjamming, all leading to financial losses.

[0003] There are a large number of oil, gas and water wells distributed in the oil field. The test well uses the hydraulic power of the logging vehicle to drive the drum to rotate, driving the cable to run up and down in the oil, gas and water wellbore. A bridle is installed at the bottom of the cable, and the bridle is connected to the testing instrument. The instrument measures various parameters in the oil, gas and water wellbore, thereby providing basic data for the production and development of oil, gas and water wells.

[0004] With the long-term production of oil, gas, and water wells, the wellbore will experience varying degrees of bending and deformation, making it easy for testing instruments to become stuck during testing. Furthermore, in some testing wells, instruments are located within the tubing. Due to the small inner diameter of the tubing and the large outer diameter of the instruments, sand and contaminants can also cause instrument jams. Horizontal wells and high-angle wells also present a risk of instrument jams due to their well conditions.

[0005] When an instrument becomes stuck, the cable cannot be properly raised and lowered for testing, requiring unjamming. This requires mechanical equipment to vigorously pull the cable, resulting in a low success rate. Furthermore, the unjamming process can easily damage the cable, wellhead equipment, and downhole instruments, posing a risk of injury and equipment failure. This increases construction risk and reduces efficiency. Damage to instruments and cable equipment, as well as labor costs associated with unjamming, results in economic losses.

[0006] Therefore, a bridle with strong applicability, simple structure, reliable performance and the ability to release the instrument when it gets stuck is needed. When the instrument gets stuck, the instrument can be released in the well, the cable can be separated from the instrument, and after the cable is pulled out, a salvage tool connected to an oil pipe is lowered into the well to fish out the test instrument, thereby simplifying the jam-releasing construction process, reducing economic losses and enhancing construction safety.

[0007] The document "Petroleum Instruments", Issue 4, 2009, pp. 20-24, introduces the development of a releasable bridle; the document "Petroleum Instruments", Issue 5, 2013, pp. 15-19, introduces the development technology of the RWCH-38 releasable bridle. Both of them basically use special alloys as the weak point, use a heating circuit to heat the special alloy of the bridle, and melt it after the instrument is stuck, thereby releasing the bridle.

[0008] Announcement No.: CN204984395U discloses a releasable bridle. When the bridle needs to be released, the power supply of the instrument during the logging process is cut off, and a specific voltage is provided to the circuit board by the ground control box. The circuit board controls the heating of the heater through the first conductive needle. After a period of time, the fuse is melted, thereby releasing the electrical part; in case the electrical part is not released, the mechanical weak point can be pulled apart.

[0009] Announcement No.: CN211666704U discloses a bridle that can release the logging cable. After the safety pin is pulled out and the bridle is installed in the well, the upper joint assembly is unlocked by controlling the driving mechanism to drive the holding part downward, thereby realizing the unlocking of the upper joint assembly by the locking assembly.

[0010] The above-mentioned prior art technology contains a circuit part with a complex structure. When the power supply circuit and the electric drive part fail, release cannot be achieved and the mechanical release capability needs to be retained, which increases the cost of the entire device.

[0011] Announcement No.: CN217841629U discloses a releasable logging bridle structure. When it needs to be unstuck, the elastic rod body is pulled out of the matching groove by pulling the cable to achieve the purpose of unstuck.

[0012] Publication No.: CN101509371A discloses a petroleum logging bridle, which uses a first cylinder to cooperate with a first connecting piece with a triple piston to achieve the purpose of fully applying the tension of the logging cable to the tension rod without being affected by the fluid pressure in the well.

[0013] Announcement No.: CN108729899B discloses a multifunctional logging bridle. When the bridle is stuck in the well, it can forcibly pull up the logging cable, causing the threaded body and tension screw of the bridle to be broken, and the part connected to the pull rod and piston rod will be pulled to the surface of the well.

[0014] The above prior art realizes release by breaking a rod or a thread, which needs to occupy a central position, so that the cable needs to be connected to the instrument through at least two side guides, which increases the overall cost of the device.

[0015] In short, the technical solutions of the above-disclosed technologies, the technical problems to be solved and the beneficial effects produced are all different from those of the present utility model. Regarding the more technical features, technical problems to be solved and the beneficial effects of the present utility model, the above-disclosed technical documents do not provide any technical inspiration. Utility Model Content

[0016] In view of the above-mentioned defects in the prior art, the purpose of the present invention is to provide a releasable bridle, which can not only realize the release of the bridle, but also reduce production costs, so that the logging cable and the core wire are always located on the central axis without being occupied and without the need for a side guide.

[0017] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0018] A releasable bridle comprises a cable connector, a working cylinder and an instrument connector, which are arranged in sequence from top to bottom. The inner diameter of the working cylinder is larger at the top and smaller at the bottom, transitioning through a shoulder, and a plate-type weak point is provided on the shoulder. The lower end of the cable connector is connected to the upper end of the working cylinder. The center of the instrument connector is a through-hole, the wall of which extends upward and passes through the plate-type weak point. The wall of the through-hole is connected to an inner salvage cap above the plate-type weak point, and the lower end face of the inner salvage cap can contact the upper end face of the plate-type weak point. The maximum outer diameter of the inner salvage cap is smaller than the lower smaller inner diameter of the working cylinder.

[0019] Furthermore, the lower end of the inner wall of the cable connector is turned into a cone basket structure, which is used to fix the outer armor of the logging cable by cooperating with the cone sleeve.

[0020] Furthermore, the cable connector is an external salvage cap, and the upper ends of the external salvage cap and the inner salvage cap are both provided with a conical structure for salvaging.

[0021] Furthermore, a keyway is provided on the outer wall of the upper end of the instrument connector, and a protruding key body is provided on the outer wall of the lower end of the working cylinder. The keyway cooperates with the protruding key body to keep the instrument and the bridle rotating synchronously.

[0022] Furthermore, a slip ring is fixedly provided at the lower end of the core hole of the instrument connector, and a terminal is fixedly provided inside the slip ring.

[0023] Furthermore, an internal thread is provided on the upper end of the hole wall of the core hole in the instrument connector to connect a sealing pin.

[0024] Furthermore, three arc-shaped sealing rings are provided on the outer wall of the sealing pin, a sealing rubber sleeve is provided inside the inner salvage cap, and the sealing pin and the sealing rubber sleeve are interference fit.

[0025] Furthermore, the sealing rubber sleeve is a rubber sleeve.

[0026] Furthermore, the lower end of the instrument connector is connected to the instrument via a threaded connection.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The utility model is applicable to the oil testing well industry and solves the following problems of instrument jamming: instrument jamming caused by sand particles, tubing deformation and other reasons during drilling and testing operations in tubing due to the small space between tubing and instrument; instrument jamming caused by casing deformation, sand jamming, and horizontal well section jamming in casing.

[0029] If the instrument is stuck, the tensile force can be increased directly to break the fragment weakness, the instrument connector working tube will be dislodged, and the instrument will be separated from the cable. After the cable is pulled out, if the test is in the oil pipe, the test instrument will be left in the oil pipe and can be pulled out together with the oil pipe; if the instrument is in the casing, the salvage tool can be lowered to salvage the inner salvage cap to pull out the test instrument.

[0030] The utility model has a release function, which can separate the instrument from the cable when it gets stuck and release the instrument in the well. At the same time, the internal salvage structure facilitates later salvage, simplifies the instrument jam processing procedure, avoids cable damage, reduces economic losses, improves construction efficiency, reduces construction risks, eliminates safety hazards, and enhances safety.

[0031] The utility model can ensure that the logging cable and the core wire are always located on the central axis when installing the logging cable and the core wire, without the need for a side guide, thereby reducing manufacturing costs, saving assembly time and improving use efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic structural diagram of a releasable bridle of the utility model;

[0033] Figure 2 It is a structural diagram of the release portion of the utility model when in use;

[0034] Figure 3 It is a schematic diagram of the structure of the utility model after being released during use;

[0035] Figure 4 This is a schematic structural diagram of the sealing pin in the utility model;

[0036] Figure 5 It is a schematic diagram of the matching structure of the working cylinder key body and the instrument connecting head keyway in the utility model.

[0037] In the figure: 1-external salvage cap; 2-working cylinder; 3-instrument connector; 4-piece weak point; 5-inner salvage cap; 6-sealing pin; 7-sealing rubber sleeve; 8-cone sleeve; 9-core wire; 10-slip ring; 11-logging cable. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] Example 1:

[0040] See also Figures 1 to 5 The utility model provides a releasable bridle, comprising an outer salvage cap 1, a working cylinder 2, and an instrument connector 3, which are arranged in sequence from top to bottom. The inner diameter of the working cylinder 2 is larger at the top and smaller at the bottom, and is transitioned through a shoulder. A sheet-type weakness 4 is provided on the shoulder. The lower end of the outer salvage cap 1 is threadedly connected to the upper end of the working cylinder 2. The center of the instrument connector 3 is a through-core hole. The wall of the through-core hole extends upward, passing through the lower small inner diameter of the working cylinder 2 and the sheet-type weakness 4. The wall of the through-core hole is connected to the inner salvage cap 5 above the sheet-type weakness 4, and the lower end surface of the inner salvage cap 5 can contact the upper end surface of the sheet-type weakness 4.

[0041] The lower end of the inner wall of the outer salvage cap 1 is turned into a cone basket structure, which is fixed to the outer armor of the logging cable 11 by cooperating with the cone sleeve 8, so that the bridle is connected between the logging cable 11 and the instrument.

[0042] Among them, the shoulder of the working cylinder 2 constitutes a shear surface. When the shoulder and the inner salvage cap 5 exert opposite pressure and the generated shear force is greater than the bearing limit of the plate-type weakness 4, the plate-type weakness 4 breaks and the bridle is released.

[0043] Among them, a slip ring 10 is provided at the lower end of the through-hole of the instrument connector 3. The slip ring 10 is made of PVC, and the slip ring 10 is interference fit with the through-hole of the connector 3 to keep it stationary; the center of the slip ring 10 is a cylindrical through hole, and the copper material terminal is inserted into the slip ring 3 and is interference fit with the slip ring 10 to keep it stationary. The upper end of the terminal is welded to the through-hole wire 9, and the lower end of the terminal is in contact with the instrument pin surface, thereby forming a transmission channel to transmit the ground power supply to the instrument, and at the same time upload the instrument test signal to the ground CNC via the cable.

[0044] The upper ends of the outer salvage cap 1 and the inner salvage cap 5 are both provided with a conical structure for salvaging.

[0045] The maximum outer diameter of the inner salvage cap 5 is smaller than the lower smaller inner diameter of the working cylinder 2 .

[0046] Furthermore, a keyway is provided on the outer wall of the upper end of the instrument connector 3, and a protruding key body is provided on the outer wall of the lower end of the working cylinder 2. The keyway cooperates with the protruding key body to keep the instrument and the bridle rotating synchronously.

[0047] Furthermore, an internal thread is provided on the upper end of the hole wall of the core hole in the instrument connector 3 to connect the sealing pin 6. Three arc-shaped sealing rings are provided on the outer wall of the sealing pin 6. A sealing rubber sleeve 7 is provided inside the inner salvage cap 5. The sealing pin 6 and the sealing rubber sleeve 7 are interference fit.

[0048] The lower end of the instrument connector 3 is connected to the instrument via a threaded connection, and the sealing pin 6 is used to disconnect the core wire 9.

[0049] Preferably, the sealing rubber sleeve 7 is made of rubber material.

[0050] The utility model solves the problem of instrument jamming during well testing. The bridle can be released quickly and safely. When the instrument is jammed, the internal components are disengaged by taking force-up measures, so that the cable and the instrument are disconnected, and then the next step of salvage and other measures are carried out to release the jam, thereby reducing the difficulty of handling the jam, eliminating safety and equipment hazards during construction, and reducing construction risks.

[0051] Example 2:

[0052] This embodiment provides a method for using a releasable bridle, which specifically includes the following steps:

[0053] S1. Fix the outer armor of the logging cable 11 by cooperating the outer salvage cap 1 and the cone sleeve 8;

[0054] S2. The upper part of the core wire 9 is hinged to the core of the logging cable 11. The sealing pin 6 is matched with the sealing rubber sleeve 7. The core wire 9 is welded to the upper end of the sealing pin 6. The sealing pin 6 is passed through the inner salvage cap 5 and the sheet-type weak point 4 in sequence. The lower end of the sealing pin 6 is welded to the lower core wire.

[0055] Then insert the working cylinder 2 so that the sheet-type weak point 4 is placed on the inner shoulder of the working cylinder 2, and connect the lower end of the sealing pin 6 to the hole wall of the wire hole in the instrument connector 3. When connecting, the keyway of the instrument connector 3 matches the protruding key body of the working cylinder 2. Then connect the inner salvage cap 5 to the inner salvage cap 5, and seal the sealing rubber sleeve 7 with the inner salvage cap 5. After the lower core wire passes through the instrument connector 3, it is welded to the terminal. Install the slip ring 10 at the lower end of the core hole of the instrument connector 3, and insert the terminal into the slip ring 10.

[0056] After completing the instrument wiring, connect the upper end of the working cylinder 2 to the outer salvage cap 1;

[0057] S3. Connect the instrument to the instrument connector 3, with the lower end of the terminal contacting the instrument pin surface, and the entire weight of the instrument acting on the chip weak point 4;

[0058] S4, such as Figure 3As shown, after the instrument is stuck, the logging cable 11 is pulled up vigorously by the power of the ground vehicle. When the pulling force is greater than the rated shear force of the plate-type weak point 4, the plate-type weak point 1 is cut off, the inner salvage cap 5 and the instrument connector 3 are removed from the working cylinder 2, and the core wire 9 is disconnected at the hinge with the logging cable 11, releasing the instrument in the well. The salvage instrument is lowered to cooperate with the inner salvage cap 5 to remove the instrument.

[0059] S5. During the lowering process, if the logging cable 11 is accidentally broken, the instrument can be removed by lowering a salvage instrument in conjunction with the outer salvage cap 1.

[0060] All components not discussed in detail in this application and the connection methods of the components in this application are well-known technologies in the technical field and can be directly applied without further explanation.

[0061] In this utility model, the term "plurality" refers to two or more, unless otherwise specified. Terms such as "installed," "connected," "connected," and "fixed" should be interpreted broadly. For example, "connected" can mean fixed, removable, or integral; "connected" can mean directly or indirectly through an intermediary. Those skilled in the art will understand the specific meanings of these terms in this utility model based on specific circumstances.

[0062] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as "up", "down", "left", "right", "front" and "back" are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the present invention.

[0063] Throughout this specification, terms such as "one embodiment," "some embodiments," and "specific embodiments" mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0064] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A releasable bridle, comprising a cable connector, a working cylinder, and an instrument connector arranged in sequence from top to bottom, characterized in that: The inner diameter of the working cylinder is larger at the top and smaller at the bottom, with a transition through a shoulder, and a plate-type weak point is provided on the shoulder; The lower end of the cable connector is connected to the upper end of the working cylinder; The center of the instrument connector is a through-hole, the hole wall of the through-hole extends upward and passes through the sheet-type weak point, the hole wall of the through-hole is connected to the inner salvage cap above the sheet-type weak point, and the lower end surface of the inner salvage cap can contact the upper end surface of the sheet-type weak point; The maximum outer diameter of the inner salvage cap is smaller than the lower smaller inner diameter of the working cylinder.

2. A releasable bridle according to claim 1, characterized in that The lower end of the inner wall of the cable connector is turned into a cone basket structure, which is matched with the cone sleeve to fix the outer armor of the logging cable.

3. A releasable bridle according to claim 1, characterized in that: The cable connector is an external salvage cap, and the upper ends of the external salvage cap and the inner salvage cap are both provided with a conical structure for salvaging.

4. A releasable bridle according to claim 1, characterized in that A keyway is provided on the outer wall of the upper end of the instrument connector, and a protruding key body is provided on the outer wall of the lower end of the working cylinder. The keyway cooperates with the protruding key body to keep the instrument and the bridle rotating synchronously.

5. A releasable bridle according to claim 1, characterized in that: The instrument connector is fixedly provided with a slip ring at the lower end of the core hole, and a terminal is fixedly provided inside the slip ring.

6. A releasable bridle according to claim 1, characterized in that: An internal thread is provided on the upper end of the hole wall of the core hole in the instrument connector to connect with a sealing pin.

7. A releasable bridle according to claim 6, characterized in that Three arc-shaped sealing rings are provided on the outer wall of the sealing pin, a sealing rubber sleeve is provided inside the inner salvage cap, and the sealing pin and the sealing rubber sleeve are interference fit.

8. A releasable bridle according to claim 7, characterized in that The sealing rubber sleeve is a rubber sleeve.

9. A releasable bridle according to claim 1, characterized in that: The lower end of the instrument connector is connected to the instrument via a threaded connection.

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