A method and apparatus for releasing a stuck instrument string in a high angle well

Abstract

The application discloses a kind of for high angle well instrument string's unjamming device, belong to oil and gas field downhole testing technical field, including rope cap and sliding cylinder, it is characterized by: still include weight, upper joint, jar rod, inner cartridge, adjusting rod, disc spring sleeve, positioning pin and lower joint, weight is located in rope cap, one end of sliding cylinder is connected with inner cartridge by thread, the other end is connected with rope cap by thread, jar rod is slidably connected with sliding cylinder, spring sleeve is arranged in inner cartridge, caliper claw and return spring are loaded in spring sleeve, adjusting rod is loaded with disc spring, sliding sleeve is arranged in lower joint, and elastic adjusting nut is loaded in sliding sleeve.The application can adapt to high angle well instrument string's unjamming, unjamming resistance is small, stress state is stable, instrument string is once continuously lifted after meeting jam, and the combined action of twice upward jar can be realized, and downward jar can be realized after meeting resistance, and the unjamming efficiency is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of downhole testing technology in oil and gas fields, and in particular to a device and method for unblocking instrument strings in highly deviated wells. Background Technology

[0002] During well testing in oil and gas fields, the instrument string enters the well. Due to the small inner diameter and high angle of the wellbore, coupled with improper technical measures, tubing coupling diameter reduction, tubing string deformation and shrinkage, and the influence of mud, formation sand, and wax buildup, the instrument string may become stuck in narrow and highly angled sections of the wellbore. Once stuck, retrieval is unavoidable. Retrieving the instrument string is not only complex and costly, but also time-consuming and inefficient. Therefore, it is urgently needed to integrate the rope cap and shock absorber into the instrument string. When the instrument string becomes stuck, a hand-cranked winch can be used to activate the tubular shock absorber to vibrate the instrument string from above and below at the stuck point, dislodging it. If the jamming is severe, an externally adjustable spring shock absorber can be used to apply strong impact force to loosen the jamming point, thereby achieving rapid release.

[0003] Currently, hydraulic shock absorbers and direct mechanical shock absorbers are commonly used for unsticking in domestic well testing tools. Hydraulic shock absorbers use rubber cup damping, but their disadvantage is that the damping mechanism is prone to damage, leading to shock absorber failure and reduced production efficiency. Direct mechanical shock absorbers, on the other hand, rely on the gravity of the weight rod in typical vertical wells and are a very effective unsticking method. However, in highly deviated wells, due to the special well structure, the shock force cannot be effectively transmitted to the sticking point, resulting in low shock force and low efficiency, failing to achieve the purpose of shock-based unsticking. Therefore, conventional direct mechanical shock absorbers are also unsuitable for unsticking requirements in highly deviated wells and are difficult to use for unsticking instrument strings.

[0004] Because these shock absorbers have a relatively simple structure, only considering single upward or downward shocking actions, their effectiveness in unblocking is poor. Furthermore, the extended length of the shock absorber makes it prone to jamming, affecting the shocking effect. This is especially problematic in working conditions with small wellbores and high inclination, where the shock absorber may bend and deform, causing shock failure and resulting in a low success rate.

[0005] With the accelerated pace of oil and gas field exploration and development, and the increasing specialization of oil and gas exploration and field operations, well testing of highly deviated wells is becoming more frequent. This places higher demands on downhole well testing and unsticking techniques. During downhole well testing operations, the shock absorber must be multifunctionalized to reliably unstick stuck instrument strings, ensuring the smooth progress of the operation.

[0006] Chinese patent document CN206233891U, published on June 9, 2017, discloses an unlocking device for a downhole instrument string. The outer tube includes an upper connector, a connecting body, an upper cylinder, a lower cylinder, and a lower connector, which are screwed together in sequence. A driving device, an unlocking device, and a shock device are installed in the inner cavity of the outer tube from top to bottom. The driving motor is connected to a lead screw, and the transmission nut of the lead screw is connected to a slip mandrel. A locking sleeve is fitted in the middle of the slip mandrel. The chuck at the lower end of the slip mandrel is inserted into the elastic slip teeth of the slip. The upper end of the locking sleeve is provided with an unlocking slope. The upper end of the shock rod is screwed to the lower end of the slip. An energy storage spring is fitted on the outer periphery of the shock rod. The lower end of the energy storage spring is supported on the outer step of the shock rod, and the upper end of the energy storage spring is supported on the inner step of the lower cylinder. An anvil is located below the shock rod, and the outer step of the anvil is supported on the upper surface of the lower connector.

[0007] The patent document discloses a device for unblocking downhole instrument strings. This device uses a lead screw and transmission nut to pull an impact rod upwards, compressing a storage spring. The released spring pushes the impact rod to strike an anvil, thus unblocking the instrument string. However, it cannot achieve the effect of two upward impacts with a single continuous upward pull, resulting in low unblocking efficiency and unsuitability for unblocking instrument strings in highly deviated wells. Summary of the Invention

[0008] In order to overcome the shortcomings of the prior art, the present invention provides a device and method for unblocking instrument strings in highly deviated wells. The present invention is suitable for unblocking instrument strings in highly deviated wells, with low unblocking resistance and stable force state. When the instrument string encounters a blockage, a single continuous upward lift can achieve the combined effect of two upward shocks, and when it encounters resistance, it can also shock downwards, which greatly improves the unblocking efficiency.

[0009] This invention is achieved through the following technical solution: A release device for a high-angle well instrument string includes a rope cap and a slide cylinder. It is characterized by further comprising a counterweight, an upper connector, a shock rod, an inner locking sleeve, an adjusting rod, a disc spring sleeve, a positioning pin, and a lower connector. One end of the upper connector is threadedly connected to the shock rod, and the other end is threadedly connected to the counterweight, which is located inside the rope cap. The inner locking sleeve is located inside the slide cylinder, with one end threadedly connected to the inner locking sleeve and the other end threadedly connected to the rope cap. The shock rod slides within the slide cylinder. A spring sleeve is installed inside the inner locking sleeve, containing a locking claw and a return spring. The disc spring sleeve is threadedly connected to the inner locking sleeve. A disc spring is mounted on the adjusting rod, located inside the disc spring sleeve, and connected to the disc spring sleeve by a positioning pin. A sliding sleeve is installed inside the lower connector, containing a spring-loaded adjusting nut, which is threadedly connected to the adjusting rod. A locking screw is installed on the lower connector.

[0010] A retaining ring is fitted on the upper part of the lower connector, and the retaining ring is located between the lower connector and the disc spring sleeve.

[0011] The hammer is cylindrical, with a flat upper end and a flat lower end.

[0012] The shock rod includes a large-diameter cylindrical section at the top and a small-diameter cylindrical section at the bottom. The length of the large-diameter cylindrical section is greater than the length of the slide tube, and the large-diameter cylindrical section is provided with a stepped surface.

[0013] The slide is cylindrical with a central hole at its center and a flat inner top surface.

[0014] The adjusting rod includes a large-diameter section and a small-diameter section. The large-diameter section has a positioning arc groove, the width and depth of which are both greater than the diameter of the positioning pin on the disc spring sleeve.

[0015] The inner cylinder is cylindrical, and its outer diameter is the same as that of the slide cylinder.

[0016] Both ends of the chuck are provided with steps, and the ends of the chucks are provided with grooves.

[0017] A method for unblocking instrument strings in highly deviated wells, characterized by comprising the following steps: a) When the instrument gets stuck, loosen the steel wire. The shock rod of the release device falls back under the weight of the hammer. When it falls back, the pin of the shock rod contacts the upper end of the chuck. The chuck is pushed down and retracts into the small diameter end of the inner chuck head. The bottom of the screw hole at the upper end of the adjusting rod restricts the chuck from moving further down. The chuck opens and the cone of the pin is inserted into the chuck. The chuck is in a closed state. The chuck is reset and enters the inner chuck under the action of the return spring. The hammer and shock rod are lifted up. When they move up, the cone of the pin hits the cone of the chuck, completing the first upward impact. b. Continue to lift the hammer, the pin drives the pawl upward, the pawl head disengages from the inner pawl and enters the slide, making the lifting force greater than the spring force of the disc spring, the pawl opens outward and the pin cone disengages, the lower step of the shock rod hits the top surface of the slide, completing the second upward impact. c. As the shock bar is released, the pawl resets and enters the inner pawl under the action of the disc spring. The steel wire is released again, and under the action of the weight of the hammer, the upper connector and the shock bar move down and fall back. The downward impact force of the pin is greater than the elastic force of the return spring below the pawl and the radial elastic force of the pawl head. The pawl opens in the inner pawl, the pin cone head is inserted into the pawl, and the pawl closes and resets, completing one cycle of shock process. d. Repeat steps ac, and vibrate again until the card is unlocked.

[0018] When the instrument encounters an obstruction, first tighten the steel wire and then loosen it. The weight of the counterweight allows it to fall freely back down. The lower end of the upper connector impacts the upper end of the slide, generating a downward shock force. This force is transmitted through the outer sleeve to the obstructed part of the instrument tool string, thus completing the unblocking process.

[0019] The beneficial effects of this invention are mainly reflected in the following aspects: 1. In this invention, one end of the upper connector is threadedly connected to the impact rod, and the other end of the upper connector is threadedly connected to the counterweight, which is located inside the rope cap. The inner clamping sleeve is located inside the sliding cylinder, with one end of the sliding cylinder threadedly connected to the inner clamping sleeve and the other end of the sliding cylinder threadedly connected to the rope cap. The impact rod and the sliding cylinder slide in cooperation. A spring sleeve is provided inside the inner clamping sleeve, which contains a pawl and a return spring. A disc spring sleeve is threadedly connected to the inner clamping sleeve. A disc spring is mounted on the adjusting rod, located inside the disc spring sleeve. The adjusting rod and the disc spring sleeve are connected by a positioning pin. A sliding sleeve is provided inside the lower connector, which contains a spring adjusting nut. The spring adjusting nut is threadedly connected to the adjusting rod. A locking screw is provided on the lower connector. Compared with the prior art, this invention can adapt to the unblocking of instrument strings in highly deviated wells, with low unblocking resistance and stable force state. When the instrument string encounters a blockage, a single continuous upward lift can achieve the combined effect of two upward impacts. After encountering resistance, it can also impact downwards, greatly improving the unblocking efficiency.

[0020] 2. In this invention, a retaining ring is fitted on the upper part of the lower connector. The retaining ring is located between the lower connector and the disc spring sleeve. By rotating the retaining ring, its radial through hole is misaligned with the locking screw, thus blocking the locking screw. This effectively prevents the locking screw from loosening and moving back, which helps to ensure the reliability and stability of the entire device.

[0021] 3. In this invention, the hammer is cylindrical with a flat upper end and a flat lower end. In use, the weight of the hammer causes the lower end of the upper connector to impact the upper end of the slide tube, generating a downward impact force that is transmitted through the outer sleeve to the jammed part of the instrument tool string, thereby achieving the purpose of unblocking. The lifting wire utilizes the kinetic energy generated by the weight of the hammer within the free stroke, causing the impact rod to collide with the chuck and generate an upward impact force, which is transmitted through the outer sleeve to the jammed part of the instrument tool string, thereby achieving the purpose of unblocking.

[0022] 4. In this invention, the shock rod includes a large-diameter cylindrical section at the top and a small-diameter cylindrical section at the bottom. The length of the large-diameter cylindrical section is greater than the length of the slide cylinder. The large-diameter cylindrical section is provided with a stepped surface. In use, the stepped surface serves as the hammering surface for the upward shock of the spring-type shocker. The shock force generated by the impact with the top surface inside the slide cylinder is transmitted through the outer sleeve to the jammed part of the instrument tool string to achieve the purpose of unblocking.

[0023] 5. In this invention, the slide is cylindrical with a central hole at its center. The inner top surface of the slide is flat and serves as the bearing surface for the upward impact of the spring-type shock absorber. It impacts the stepped surface of the large-diameter cylindrical section of the shock absorber to generate shock force. The structural design is novel and reasonable, and the operation is more convenient.

[0024] 6. In this invention, the adjusting rod includes a large-diameter section and a small-diameter section. A positioning arc groove is formed on the large-diameter section. The width and depth of the positioning arc groove are both greater than the diameter of the positioning pin on the disc spring sleeve. The entire adjusting rod has a simple structure. The positioning arc groove facilitates the effective positioning of the positioning pin and ensures the stability of the device.

[0025] 7. In this invention, the inner clamping cylinder is cylindrical, and the outer diameter of the inner clamping cylinder is the same as the outer diameter of the sliding cylinder, which makes the whole device more integrated and neater.

[0026] 8. In this invention, steps are provided at both ends of the claw, and grooves are opened at the ends of the claw, so that the entire claw can maintain good elasticity, which facilitates the smooth entry and exit of the vibration rod and improves the reliability of the entire device.

[0027] 9. In this invention, a) when the instrument gets stuck, the steel wire is released, and the shock rod of the unblocking device falls back under the weight of the hammer. When it falls back, the pin of the shock rod contacts the upper end of the chuck, and the chuck is pushed back into the small-diameter end of the inner chuck head. The bottom of the screw hole at the upper end of the adjusting rod restricts the chuck from moving further down. The chuck opens, and the cone of the pin is inserted into the chuck. The chuck is in a closed state. The chuck returns to its original position under the action of the return spring and enters the inner chuck. The hammer and shock rod are lifted upward. When they move upward, the cone of the pin hits the cone of the chuck, completing the first upward impact; b) the hammer is lifted further, and the pin drives the chuck upward. The chuck head disengages from the inner chuck and enters the slide. Inside, the upward pulling force is greater than the spring force of the disc spring, causing the chuck to open outward and disengage the pin cone. The lower step of the shock rod impacts the top surface of the inner tube, completing the second upward impact. c. Simultaneously with the release of the shock rod, the chuck returns to its original position under the spring force of the disc spring and enters the inner chuck. The steel wire is released again, and under the gravity of the hammer, the upper connector and shock rod move downward and fall back. The downward impact force of the pin is greater than the spring force of the return spring below the chuck and the radial spring force of the chuck head. The chuck opens inside the inner chuck, the pin cone inserts into the chuck, and the chuck retracts and returns to its original position, completing one cycle of shock process. d. Repeat steps a and c, shocking again until the chuck is released. As a complete technical solution, compared with existing technologies, it has multiple upward shock functions and can also be used for downward shocks, greatly improving the efficiency of chuck release in high-angle well operations. It has a wide range of applications and strong operability.

[0028] 10. In this invention, when the instrument encounters an obstruction, the steel wire is first tightened and then loosened. The weight of the hammer allows it to fall freely back down. The lower end plane of the upper connector impacts the upper end surface of the slide tube, generating a downward shock force. This force is transmitted through the outer sleeve to the obstructed part of the instrument tool string, thus completing the unblocking process. The entire unblocking process is simple and easy to operate. Attached Figure Description

[0029] The present invention will now be further described in detail with reference to the accompanying drawings and specific embodiments: Figure 1This is a cross-sectional view of the card unlocking device of the present invention; Figure 2 This is a schematic diagram of the card unlocking device of the present invention; The markings in the diagram are: 1. Rope cap, 2. Counterweight, 3. Upper connector, 4. Vibration rod, 5. Slide cylinder, 6. Inner retaining sleeve, 7. Claw, 8. Return spring, 9. Spring sleeve, 10. Adjusting rod, 11. Positioning pin, 12. Disc spring, 13. Disc spring sleeve, 14. Spring adjusting nut, 15. Lower connector, 16. Sliding sleeve, 17. Retaining ring, 18. Locking screw. Detailed Implementation

[0030] Example 1 See Figure 1 and Figure 2 A device for unjamming a string of instruments in a highly deviated well includes a rope cap 1 and a slide cylinder 5, as well as a counterweight 2, an upper connector 3, a vibrating rod 4, an inner clamping sleeve 6, an adjusting rod 10, a disc spring sleeve 13, a positioning pin 11, and a lower connector 15. One end of the upper connector 3 is threadedly connected to the vibrating rod 4, and the other end of the upper connector 3 is threadedly connected to the counterweight 2. The counterweight 2 is located inside the rope cap 1. The inner clamping sleeve 6 is located inside the slide cylinder 5. One end of the slide cylinder 5 is threadedly connected to the inner clamping sleeve 6, and the other end of the slide cylinder 5 is threadedly connected to the rope cap 1. The vibrating rod 4 is threadedly connected to the slide cylinder 5. The inner sleeve 6 is provided with a sliding fit, and a spring sleeve 9 is provided inside the inner sleeve 6. The spring sleeve 9 contains a pawl 7 and a return spring 8. The disc spring sleeve 13 is connected to the inner sleeve 6 by a thread. The adjusting rod 10 is equipped with a disc spring 12, which is located inside the disc spring sleeve 13. The adjusting rod 10 and the disc spring sleeve 13 are connected by a positioning pin 11. The lower connector 15 is provided with a sliding sleeve 16, and a spring adjusting nut 14 is provided inside the sliding sleeve 16. The spring adjusting nut 14 is connected to the adjusting rod 10 by a thread. The lower connector 15 is provided with a locking screw 18.

[0031] This embodiment is the most basic implementation method. Compared with the prior art, it can adapt to the unblocking of instrument strings in wells with large deviance. The unblocking resistance is small and the force state is stable. When the instrument string encounters a blockage, a single continuous upward pull can achieve the combined effect of two upward shocks. When it encounters resistance, it can also shock downwards, which greatly improves the unblocking efficiency.

[0032] Example 2 See Figure 1 and Figure 2A device for unjamming a string of instruments in a highly deviated well includes a rope cap 1 and a slide cylinder 5, as well as a counterweight 2, an upper connector 3, a vibrating rod 4, an inner clamping sleeve 6, an adjusting rod 10, a disc spring sleeve 13, a positioning pin 11, and a lower connector 15. One end of the upper connector 3 is threadedly connected to the vibrating rod 4, and the other end of the upper connector 3 is threadedly connected to the counterweight 2. The counterweight 2 is located inside the rope cap 1. The inner clamping sleeve 6 is located inside the slide cylinder 5. One end of the slide cylinder 5 is threadedly connected to the inner clamping sleeve 6, and the other end of the slide cylinder 5 is threadedly connected to the rope cap 1. The vibrating rod 4 is threadedly connected to the slide cylinder 5. The inner sleeve 6 is provided with a sliding fit, and a spring sleeve 9 is provided inside the inner sleeve 6. The spring sleeve 9 contains a pawl 7 and a return spring 8. The disc spring sleeve 13 is connected to the inner sleeve 6 by a thread. The adjusting rod 10 is equipped with a disc spring 12, which is located inside the disc spring sleeve 13. The adjusting rod 10 and the disc spring sleeve 13 are connected by a positioning pin 11. The lower connector 15 is provided with a sliding sleeve 16, and a spring adjusting nut 14 is provided inside the sliding sleeve 16. The spring adjusting nut 14 is connected to the adjusting rod 10 by a thread. The lower connector 15 is provided with a locking screw 18.

[0033] Furthermore, a retaining ring 17 is fitted on the upper part of the lower connector 15, and the retaining ring 17 is located between the lower connector 15 and the disc spring sleeve 13.

[0034] The hammer 2 is cylindrical, with a flat upper end and a flat lower end.

[0035] The shock rod 4 includes a large-diameter cylindrical section at the top and a small-diameter cylindrical section at the bottom. The length of the large-diameter cylindrical section is greater than the length of the slide cylinder 5, and the large-diameter cylindrical section is provided with a stepped surface.

[0036] This embodiment is a preferred implementation. A retaining ring 17 is fitted on the upper part of the lower connector 15. The retaining ring 17 is located between the lower connector 15 and the disc spring sleeve 13. By rotating the retaining ring 17, its radial through hole is misaligned with the locking screw 18, blocking the locking screw 18. This can effectively prevent the locking screw 18 from loosening and moving back, which helps to ensure the reliability and stability of the entire device.

[0037] The weight 2 is cylindrical with a flat upper end and a flat lower end. In use, the weight of the weight 2 causes the lower end of the upper connector 3 to collide with the upper end of the slide cylinder 5, generating a downward impact force that is transmitted through the outer sleeve to the jammed part of the instrument tool string, thereby achieving the purpose of unblocking. The lifting wire utilizes the kinetic energy generated by the weight of the weight 2 within the free stroke, causing the shock rod 4 to collide with the chuck 7, generating an upward impact force that is transmitted through the outer sleeve to the jammed part of the instrument tool string, thereby achieving the purpose of unblocking.

[0038] The shock rod 4 includes a large-diameter cylindrical section at the top and a small-diameter cylindrical section at the bottom. The length of the large-diameter cylindrical section is greater than the length of the slide cylinder 5. The large-diameter cylindrical section is provided with a stepped surface. When in use, the stepped surface serves as the hammering surface for the spring-type shocker to strike upwards. The shock force generated by the impact with the inner top surface of the slide cylinder 5 is transmitted through the outer sleeve to the jammed part of the instrument tool string to achieve the purpose of unblocking.

[0039] Example 3 See Figure 1 and Figure 2 A device for unjamming a string of instruments in a highly deviated well includes a rope cap 1 and a slide cylinder 5, as well as a counterweight 2, an upper connector 3, a vibrating rod 4, an inner clamping sleeve 6, an adjusting rod 10, a disc spring sleeve 13, a positioning pin 11, and a lower connector 15. One end of the upper connector 3 is threadedly connected to the vibrating rod 4, and the other end of the upper connector 3 is threadedly connected to the counterweight 2. The counterweight 2 is located inside the rope cap 1. The inner clamping sleeve 6 is located inside the slide cylinder 5. One end of the slide cylinder 5 is threadedly connected to the inner clamping sleeve 6, and the other end of the slide cylinder 5 is threadedly connected to the rope cap 1. The vibrating rod 4 is threadedly connected to the slide cylinder 5. The inner sleeve 6 is provided with a sliding fit, and a spring sleeve 9 is provided inside the inner sleeve 6. The spring sleeve 9 contains a pawl 7 and a return spring 8. The disc spring sleeve 13 is connected to the inner sleeve 6 by a thread. The adjusting rod 10 is equipped with a disc spring 12, which is located inside the disc spring sleeve 13. The adjusting rod 10 and the disc spring sleeve 13 are connected by a positioning pin 11. The lower connector 15 is provided with a sliding sleeve 16, and a spring adjusting nut 14 is provided inside the sliding sleeve 16. The spring adjusting nut 14 is connected to the adjusting rod 10 by a thread. The lower connector 15 is provided with a locking screw 18.

[0040] A retaining ring 17 is fitted on the upper part of the lower connector 15, and the retaining ring 17 is located between the lower connector 15 and the disc spring sleeve 13.

[0041] The hammer 2 is cylindrical, with a flat upper end and a flat lower end.

[0042] The shock rod 4 includes a large-diameter cylindrical section at the top and a small-diameter cylindrical section at the bottom. The length of the large-diameter cylindrical section is greater than the length of the slide cylinder 5, and the large-diameter cylindrical section is provided with a stepped surface.

[0043] Furthermore, the slide cylinder 5 is cylindrical, with a central hole at its center, and the inner top surface of the slide cylinder 5 is flat.

[0044] The adjusting rod 10 includes a large-diameter section and a small-diameter section. The large-diameter section has a positioning arc groove. The width and depth of the positioning arc groove are both greater than the diameter of the positioning pin 11 on the disc spring sleeve 13.

[0045] The inner clamping cylinder 6 is cylindrical, and its outer diameter is the same as that of the sliding cylinder 5.

[0046] Both ends of the claw 7 are provided with steps, and the ends of the claw 7 are provided with grooves.

[0047] This embodiment is another preferred implementation. The slide cylinder 5 is cylindrical, with a central hole at its center. The inner top surface of the slide cylinder 5 is flat. The inner top surface of the slide cylinder 5 serves as the bearing surface for the upward impact of the spring-type shock absorber. It impacts the stepped surface of the large-diameter cylindrical section of the shock absorber 4 to generate shock force. The structural design is novel and reasonable, and the operation is more convenient.

[0048] The adjusting rod 10 includes a large-diameter section and a small-diameter section. The large-diameter section has a positioning arc groove. The width and depth of the positioning arc groove are both greater than the diameter of the positioning pin 11 on the disc spring sleeve 13. The entire adjusting rod 10 has a simple structure. The positioning arc groove facilitates the effective positioning of the positioning pin 11 and ensures the stability of the device.

[0049] The inner clamping cylinder 6 is cylindrical, and its outer diameter is the same as that of the sliding cylinder 5, which makes the whole device more integrated and neat.

[0050] Both ends of the chuck 7 are provided with steps, and the ends of the chuck 7 are provided with grooves, so that the entire chuck 7 can maintain good elasticity, which facilitates the smooth entry and exit of the shock rod 4 and improves the reliability of the entire device.

[0051] Example 4 See Figure 1 and Figure 2 A method for unblocking instrument strings in highly deviated wells includes the following steps: a. When the instrument gets stuck, the steel wire is released, and the shock rod 4 of the release device falls back under the gravity of the hammer 2. When it falls back, the pin of the shock rod 4 contacts the upper end of the pawl 7. The pawl 7 is pressed down and retracts into the small diameter end of the head of the inner pawl 6. The bottom of the screw hole at the upper end of the adjusting rod 10 restricts the pawl 7 from moving further down. The pawl 7 opens, and the cone of the pin is inserted into the pawl 7. The pawl 7 is in the closed state. The pawl 7 is reset and enters the inner pawl 6 under the action of the return spring 8. The hammer 2 and the shock rod 4 are lifted up. When they move up, the cone of the pin hits the cone of the pawl 7, completing the first upward impact. b. Continue to lift the hammer 2, the pin drives the pawl 7 to move upward, the head of the pawl 7 disengages from the inner pawl 6 and enters the slide 5, so that the lifting force is greater than the elastic force of the disc spring 12, the pawl 7 opens outward to disengage the pin cone, the lower step of the shock rod 4 hits the top surface of the slide 5, and the second upward impact is completed. c. As the shock rod 4 is released, the pawl 7 returns to its original position and enters the inner pawl 6 under the elastic force of the disc spring 12. The steel wire is released again, and under the gravity of the hammer 2, the upper connector 3 and the shock rod 4 move down and fall back. The downward impact force of the pin is greater than the elastic force of the return spring 8 below the pawl 7 and the radial elastic force of the head of the pawl 7. The pawl 7 opens in the inner pawl 6, the pin cone head is inserted into the pawl 7, and the pawl 7 closes and returns to its original position, completing one cycle of shock process. d. Repeat steps ac, and vibrate again until the card is unlocked.

[0052] This embodiment is another preferred implementation method. As a complete technical solution, compared with the prior art, it has multiple upward shock functions and can also be used for downward shocks, which greatly improves the efficiency of unblocking in high-angle well operations. It has a wide range of applications and strong operability.

[0053] Example 5 See Figure 1 and Figure 2 A method for unblocking instrument strings in highly deviated wells includes the following steps: a. When the instrument gets stuck, the steel wire is released, and the shock rod 4 of the release device falls back under the gravity of the hammer 2. When it falls back, the pin of the shock rod 4 contacts the upper end of the pawl 7. The pawl 7 is pressed down and retracts into the small diameter end of the head of the inner pawl 6. The bottom of the screw hole at the upper end of the adjusting rod 10 restricts the pawl 7 from moving further down. The pawl 7 opens, and the cone of the pin is inserted into the pawl 7. The pawl 7 is in the closed state. The pawl 7 is reset and enters the inner pawl 6 under the action of the return spring 8. The hammer 2 and the shock rod 4 are lifted up. When they move up, the cone of the pin hits the cone of the pawl 7, completing the first upward impact. b. Continue to lift the hammer 2, the pin drives the pawl 7 to move upward, the head of the pawl 7 disengages from the inner pawl 6 and enters the slide 5, so that the lifting force is greater than the elastic force of the disc spring 12, the pawl 7 opens outward to disengage the pin cone, the lower step of the shock rod 4 hits the top surface of the slide 5, and the second upward impact is completed. c. As the shock rod 4 is released, the pawl 7 returns to its original position and enters the inner pawl 6 under the elastic force of the disc spring 12. The steel wire is released again, and under the gravity of the hammer 2, the upper connector 3 and the shock rod 4 move down and fall back. The downward impact force of the pin is greater than the elastic force of the return spring 8 below the pawl 7 and the radial elastic force of the head of the pawl 7. The pawl 7 opens in the inner pawl 6, the pin cone head is inserted into the pawl 7, and the pawl 7 closes and returns to its original position, completing one cycle of shock process.

[0054] d. Repeat steps ac, and vibrate again until the card is unlocked; When the instrument encounters an obstruction, the steel wire is first tightened and then loosened. The weight of the counterweight 2 allows it to fall freely back down. The lower end of the upper connector 3 impacts the upper end of the slide cylinder 5, generating a downward shock force. This force is transmitted through the outer sleeve to the obstructed part of the instrument tool string, thus completing the unblocking process.

[0055] This embodiment is the best implementation method. When the instrument encounters an obstruction, the steel wire is first tightened and then loosened. The weight of the hammer 2 is used to allow it to fall freely back. The lower end plane of the upper connector 3 impacts the upper end surface of the slide cylinder 5, generating a downward shock force. This force is transmitted through the outer sleeve to the obstructed part of the instrument tool string, thus completing the unblocking process. The entire unblocking process is simple and easy to operate.

[0056] The card unlocking principle of this invention is as follows: The hammer 2 is connected to the upper connector 3 and is fitted inside the rope cap 1 and connected to the slide cylinder 5. The end of the shock rod 4 is provided with a pin. The slide cylinder 5 is connected to the inner clamp 6. The return spring 8 and the pawl 7 are fitted inside the spring sleeve 9 and are connected to the external thread of the upper end of the adjusting rod 10. The adjusting rod 10 is inserted into the disc spring sleeve 13. The disc spring 12 passes through the adjusting rod 10 and is fitted inside the disc spring sleeve 13. The spring adjusting nut 14 is fitted inside the sliding sleeve 16. The retaining ring 17 is fitted in the middle of the sliding sleeve 16. Then the sliding sleeve 16 is fitted inside the connector of the disc spring sleeve 13. The external thread of the lower connector 15 is connected to the internal thread of the disc spring sleeve 13. The pawl 7 is connected to the adjusting rod 10 and installed inside the inner clamp 6. The pin cone of the shock rod 4 is inserted into the pawl 7. The shock force is adjusted by a force adjustment tool. To adjust the magnitude of the impact force, the tightness of the connection between the elastic adjusting nut 14 and the adjusting rod 10 must be adjusted, which will be converted into the elastic force of the disc spring 12. Then, the locking screw 18 is used to lock it in place, and the retaining ring 17 is used to block the locking screw 18 to prevent it from loosening and moving back. The rope cap 1 and the slide 5 are provided with drainage holes.

[0057] When the tool is lifted, the conical surface of the pin head of the vibrating rod 4 collides with the conical surface of the pawl 7, completing the first upward vibration; when the tool is lifted further, the pin head of the vibrating rod 4 drives the pawl 7 to move upward until it disengages from the end face of the inner pawl 6. The pawl 7 opens, thereby disengaging the vibrating rod 4. The spring force of the disc spring 12 is released instantly, and the lower step of the vibrating rod 4 collides with the top surface of the slide cylinder 5, completing the second upward vibration.

[0058] As the shock rod 4 is released, the pawl 7, under the elastic force of the disc spring 12, resets and enters the inner pawl 6. The steel wire is slowly released, and under the gravity of the counterweight 2, the upper connector 3, shock rod 4, and pin move downwards. The downward impact force of the pin is much greater than the elastic force of the return spring 8 below the pawl 7 and the radial elastic force of the pawl 7 head. The pawl 7 opens within the inner pawl 6, the pin cone inserts into the pawl 7, and the pawl 7 retracts and resets. The downward shock force generated by the impact between the lower stepped surface of the upper connector 3 and the upper surface of the slide cylinder 5 is transmitted through the outer sleeve to the obstructed part of the instrument tool string, achieving the purpose of unblocking. The shocker then completes the entire process of two upward shocks and one downward shock in one cycle.

[0059] Rapidly lowering the steel wire: Utilizing the weight of the hammer 2, within a limited stroke, the downward impact force generated by the collision between the lower stepped surface of the upper connector 3 and the upper surface of the slide cylinder 5 is transmitted through the outer sleeve to the jammed part of the instrument tool string, achieving the purpose of unblocking; When lifting the steel wire, the kinetic energy generated by the weight of the hammer 2 is used within the free stroke, and the impact force generated by the collision between the pin conical surface of the shock rod 4 and the conical surface of the chuck 7 is transmitted through the outer sleeve to the jammed part of the instrument tool string, achieving the purpose of unblocking.

[0060] The disc spring 12 occupies little axial space but stores a large amount of deformation energy. When the pin of the shock rod 4 disengages from the pawl 7, it is unlocked. The shock rod 4 moves upward rapidly, and its lower step impacts the top surface of the inner cylinder of the slide 5, generating a large impact force.

[0061] The winch has a two-stage upward shock function. When the downhole instrument tool string gets stuck, the winch lowers the wire to a slack state and then tightens the wire in the opposite direction. During the tightening process, the shocker can generate two consecutive upward shocks. The first shock is generated by the impact of the pin cone of the shock rod 4 against the cone of the chuck 7. The second shock is generated by the impact of the lower step of the shock rod 4 against the top surface of the inner cylinder of the slide 5.

Claims

1. A method for unblocking instrument strings in highly deviated wells, characterized in that, Includes the following steps: a. When the instrument gets stuck, loosen the steel wire. The shock rod (4) of the unblocking device falls back under the gravity of the hammer (2). When it falls back, the pin of the shock rod (4) contacts the upper end of the pawl (7). Press down the pawl (7) and it moves back into the small diameter end of the head of the inner pawl (6). The bottom of the screw hole at the upper end of the adjusting rod (10) restricts the pawl (7) from moving down. The pawl (7) opens and the pin cone is inserted into the pawl (7). The pawl (7) is in a closed state. The pawl (7) is reset and enters the inner pawl (6) under the action of the return spring (8). The hammer (2) and the shock rod (4) are lifted up. When they move up, the pin cone hits the cone of the pawl (7) to complete the first upward impact. b. Continue to lift the hammer (2), the pin drives the pawl (7) to move upward, the head of the pawl (7) disengages from the inner pawl (6) and enters the slide (5), so that the lifting force is greater than the elastic force of the disc spring (12), the pawl (7) opens outward so that the pin cone disengages, the lower step of the shock rod (4) hits the top surface of the slide (5), and completes the second upward impact; c. As the shock rod (4) is released, the pawl (7) resets and enters the inner pawl (6) under the elastic force of the disc spring (12). The steel wire is released again. Under the gravity of the hammer (2), the upper connector (3) and the shock rod (4) move down and fall back. The downward impact force of the pin is greater than the elastic force of the return spring (8) below the pawl (7) and the radial elastic force of the head of the pawl (7). The pawl (7) opens in the inner pawl (6), the pin cone is inserted into the pawl (7), and the pawl (7) closes and resets, completing one cycle of shock process. d. Repeat steps ac, and vibrate again until the card is unlocked; The unblocking device includes a rope cap (1), a slide cylinder (5), a counterweight (2), an upper connector (3), a shock rod (4), an inner locking cylinder (6), an adjusting rod (10), a disc spring sleeve (13), a positioning pin (11), and a lower connector (15). One end of the upper connector (3) is threadedly connected to the shock rod (4), and the other end of the upper connector (3) is threadedly connected to the counterweight (2). The counterweight (2) is located inside the rope cap (1). The inner locking cylinder (6) is located inside the slide cylinder (5). One end of the slide cylinder (5) is threadedly connected to the inner locking cylinder (6), and the other end of the slide cylinder (5) is threadedly connected to the rope cap (1). The shock rod (4) and the slide cylinder (5) slide in cooperation. The inner sleeve (6) is provided with a spring sleeve (9), and the spring sleeve (9) is provided with a claw (7) and a return spring (8). The disc spring sleeve (13) is connected to the inner sleeve (6) by a thread. The adjusting rod (10) is provided with a disc spring (12), and the disc spring (12) is located inside the disc spring sleeve (13). The adjusting rod (10) is connected to the disc spring sleeve (13) by a positioning pin (11). The lower connector (15) is provided with a sliding sleeve (16), and the sliding sleeve (16) is provided with a spring adjusting nut (14). The spring adjusting nut (14) is connected to the adjusting rod (10) by a thread. The lower connector (15) is provided with a locking screw (18).

2. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: The lower connector (15) is fitted with a retaining ring (17) on its upper part, and the retaining ring (17) is located between the lower connector (15) and the disc spring sleeve (13).

3. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: The hammer (2) is cylindrical, with a flat upper end and a flat lower end.

4. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: The shock rod (4) includes a large-diameter cylindrical section at the top and a small-diameter cylindrical section at the bottom. The length of the large-diameter cylindrical section is greater than the length of the slide cylinder (5), and the large-diameter cylindrical section is provided with a stepped surface.

5. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: The slide cylinder (5) is cylindrical, with a central hole at the center and a flat inner top surface.

6. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: The adjusting rod (10) includes a large-diameter section and a small-diameter section. The large-diameter section has a positioning arc groove. The width and depth of the positioning arc groove are both greater than the diameter of the positioning pin (11) on the disc spring sleeve (13).

7. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: The inner cylinder (6) is cylindrical, and the outer diameter of the inner cylinder (6) is the same as the outer diameter of the slide cylinder (5).

8. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: Both ends of the claw (7) are provided with steps, and the ends of the claw (7) are provided with grooves.

9. The method for unblocking instrument strings in highly deviated wells according to claim 1, characterized in that: When the instrument encounters an obstruction, first tighten the steel wire and then loosen it. Using the weight of the hammer (2), it falls freely back down. The lower end plane of the upper connector (3) hits the upper end surface of the slide (5) to generate a downward shock force, which is transmitted through the outer sleeve to the obstructed part of the instrument tool string, thus completing the unblocking.

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