A device for improving hydraulic pumping efficiency and a control method thereof

Abstract

The present invention relates to the technical field of cable pumping bridge plugs and perforating in unconventional horizontal wells, and specifically to a device for improving hydraulic pumping efficiency and a control method. The device comprises an upper connector, an intermediate shell, a lower connector, a reducer assembly, an adjustment spindle, an upper spring, and an adjustment ring; wherein one end of the adjustment spindle is fixedly connected to the upper connector, and the other end is slidably plugged with the lower connector, and the middle section passes through the intermediate shell; one end of the upper connector is plugged into the intermediate shell, and is slidably plugged with the intermediate shell; an axial positioning step is provided in the intermediate shell, and the axial positioning step is limitedly matched with the upper connector; the intermediate shell is fixedly sleeved with the lower connector; the device can solve the problems of low pumping efficiency, high displacement and easy jamming and pump-out hazards existing in 5½″ reduced-diameter or sleeve-changed casings, and improve the pumping efficiency and passing capacity of small-diameter cable pumping bridge plugs and perforating pipe strings. The device has the characteristics of high safety and reliability, easy implementation, and low manufacturing cost.

Description

Technical Field

[0001] The invention relates to the technical field of unconventional horizontal well cable pumping bridge plug and perforation, and in particular to a device for improving hydraulic pumping efficiency and a control method. Background Art

[0002] In early 2006, the Oil and Gas Resources Planning Institute of the China Petroleum Exploration and Development Research Institute organized experts to conduct a shale gas resource survey in the southwest of the Sichuan Basin. According to the volumetric method, China's shale gas resources alone are as high as 26 to 31 trillion cubic meters, which is equivalent to the shale gas reserves in the United States. my country's dependence on foreign crude oil is increasing year by year, while the United States' dependence on foreign crude oil is decreasing year by year. Among them, alternative energy sources such as shale oil and gas have played an extremely important role. The large-scale exploitation of shale oil and gas is inseparable from the development and application of unconventional horizontal well cable pumping bridge plug cluster perforation and segmented hydraulic fracturing technology.

[0003] Sichuan and Chongqing are one of the main shale gas bases in my country. The geological conditions in the region are relatively complex. Most shale horizontal wells are more than 5,500 meters deep, with vertical depths exceeding 4,000 meters and horizontal lengths exceeding 1,500 meters. The formation pressure is high and the wellbore environment is becoming increasingly complex. Earthquakes often occur. During the large-scale staged fracturing process, more and more casing shrinkage and casing deformation wells occur, which brings great difficulties to the cable pumping bridge plug perforation joint construction.

[0004] At present, the commonly used 89-type perforating gun string equipped with Baker 20# bridge plug sealing tool can no longer cope with this type of engineering problem. The 73 and 80-type small-diameter perforating gun strings equipped with Baker 10# bridge plug sealing tools can meet engineering needs to a certain extent, but there is a problem of difficulty in pumping in 5½″ casing. If the displacement is increased, there will be a risk of the cable pushing through the tool string and the wellhead pressure being unsealed, which may easily lead to engineering accidents such as jamming, pumping out of the gun string, and cable breaking; if the displacement is reduced, the tool string cannot be pushed. Therefore, how to improve the pumping efficiency of small-diameter joint gun strings has become a key technology that needs to be overcome.

[0005] Although the continuous tubing perforation method can meet the engineering requirements to a certain extent, it can only complete the bridge plugging operation in one trip to the well, or at most complete the ignition perforation of two clusters of perforating guns. The bridge plugging and perforating cannot be performed together, which not only increases the workload and reduces the construction efficiency, but also increases the safety risks.

[0006] Therefore, in view of the above existing problems, this invention designs a device and control method for improving hydraulic pumping efficiency, so as to improve the pumping efficiency and passing capacity of small-diameter cable pumping bridge plugs and perforating pipe strings. No similar public reports were found through inquiries of relevant technical literature and patents at home and abroad. Summary of the invention

[0007] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a device and control method for improving the hydraulic pumping efficiency. The pumping efficiency and throughput capacity of small-diameter cable pumping bridge plugs and perforating pipe strings are improved to address the problems of low pumping efficiency, easy jamming and pumping out hazards of large displacement in 5½" reduced diameter or sleeve-changed casing.

[0008] The technical solution is as follows:

[0009] A device for improving hydraulic pumping efficiency comprises an upper connector, an intermediate shell, a lower connector, a reducer assembly, an adjustment spindle, an upper spring and an adjustment ring; wherein, one end of the adjustment spindle is fixedly connected to the upper connector, and the other end is slidably plugged into the lower connector, and the middle section passes through the intermediate shell; one end of the upper connector is plugged into the intermediate shell and slidably plugged into the intermediate shell; an axial positioning step is provided in the intermediate shell, and the axial positioning step is limitedly matched with the upper connector; the intermediate shell is fixedly sleeved with the lower connector; one end of the reducer assembly is fixedly sleeved on the upper connector, and the other end is fixedly sleeved on the intermediate shell; the upper spring is sleeved on the adjustment spindle and is located between the axial positioning step and the adjustment ring; the adjustment ring is threadedly connected to the middle section of the adjustment spindle and is located in the intermediate shell.

[0010] Furthermore, the variable diameter assembly includes a left fixed ring, a right fixed ring, and a variable diameter umbrella. The left fixed ring is fixedly sleeved on the upper connecting head, the right fixed ring is fixedly sleeved on the intermediate shell, and both ends of the variable diameter umbrella are sealed and fixedly connected to the left and right fixed rings.

[0011] The variable diameter umbrella is made of flexible material.

[0012] An elastic metal frame is embedded inside the variable diameter umbrella.

[0013] The flexible material includes plastic, fiber (nylon), rubber or a mixture thereof.

[0014] An adjustment hole is provided on the side wall of the intermediate shell.

[0015] The outer walls of the upper connecting head and the lower connecting head are provided with wrench holes which are arranged circumferentially.

[0016] Furthermore, a sliding step is provided at one end of the upper connector, the sliding step is plugged into the intermediate housing, and is slidingly and sealingly matched with the intermediate housing, and the sliding step is limitedly matched with the axial positioning step.

[0017] The intermediate shell is threadedly and sealingly connected to the lower connecting head.

[0018] An adjustable spindle movable through hole is arranged in the lower connecting head, and the adjustable spindle movable through hole is matched with the adjustable spindle in a sliding and sealing manner.

[0019] A through-line through hole which penetrates axially is arranged inside the adjusting spindle.

[0020] It also includes a lower spring, which is sleeved on the adjusting spindle and located between the adjusting ring and the lower connecting head.

[0021] The beneficial effects of the present invention are:

[0022] It can solve the problems of low pumping efficiency in 5½" reduced diameter or sleeve-changing casing, easy jamming and pump-out hazards in large displacement, and improve the pumping efficiency and throughput capacity of small-diameter cable pumping bridge plugs and perforating pipe strings. It has the characteristics of high safety and reliability, easy implementation and low manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of the present invention;

[0024] Figure 2 1 is a schematic diagram of the upper connector structure;

[0025] Figure 3 is a schematic diagram of the intermediate shell structure;

[0026] Figure 4 1 is a schematic diagram of the lower connector structure;

[0027] Figure 5 It is a schematic diagram of the adjustment spindle structure;

[0028] Figure 6 1. It is a schematic diagram of the structure of the reducer assembly;

[0029] In the figure: upper connector 1, intermediate housing 2, lower connector 3, adjusting spindle 4, reducer assembly 5, adjusting ring 6, upper spring 7, lower spring 8, sealing groove 1-1, wrench hole 1-2, fixed external thread 1-3, sliding step 1-4, through hole 1-5, spindle internal thread 1-6, spindle sealing surface 1-7, spindle through hole 1-8, wrench hole 2-2, water tank 2-3, internal thread 2-4, sealing surface 2-5, sliding Through hole 2-6, spindle through hole 2-7, adjustment hole 2-8, sealing groove 3-1, wrench hole 3-2, sealing groove 3-3, spindle movable through hole 3-4, external thread 4-1, sealing groove 4-2, adjustment external thread 4-3, sealing groove 4-4, through-line through hole 4-5, left fixing ring 5-1, right fixing ring 5-2, fixed internal threads 5-4, 5-5, variable diameter umbrella 5-3, fixed internal threads 5-4, 5-5. DETAILED DESCRIPTION

[0030] In order to make the purpose and technical solution of the embodiments of the present invention clearer, the embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments, wherein the same or similar numbers from beginning to end represent the same or similar elements or elements with the same or similar functions, and elements with the same function appear with only one number. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0031] Embodiment 1:

[0032] See attached Figure 1 A device for improving hydraulic pumping efficiency includes an upper connector 1, an intermediate housing 2, a lower connector 3, an adjustment spindle 4, a reducer assembly 5, an adjustment ring 6, an upper spring 7, and a lower spring 8.

[0033] See attached Figure 2 The left end of the upper connector 1 is provided with an external thread and a sealing groove 1-1, four wrench holes 1-2 are evenly arranged around the middle, a fixed external thread 1-3 and a sliding step 1-4 are arranged at the right end, and a through hole 1-5, a spindle internal thread 1-6, a spindle sealing surface 1-7, and a spindle through hole 1-8 are arranged on the inner side.

[0034] See attached Figure 3 The left end of the intermediate shell 2 is provided with a fixed external thread 2-1, the outer side of the shell is provided with four wrench holes 2-2 and four water grooves 2-3, the inner side of the right end is provided with an internal thread 2-4 and a sealing surface 2-5, and the inner side of the left end is provided with a sliding through hole 2-6, a spindle through hole 2-7, and an adjustment hole 2-8.

[0035] See attached Figure 4 The left end of the lower connector 3 is also provided with an external thread and a sealing groove 3-1, four wrench holes 3-2 are arranged around the middle outer side, the right end is also provided with an external thread and a sealing groove 3-3, and a spindle movable through hole 3-4 is arranged on the inner side.

[0036] See attached Figure 5 The left end of the adjustment spindle 4 is also provided with an external thread 4-1 and a sealing groove 4-2, an adjustment external thread 4-3 is provided in the middle of the outer side, a sealing groove 4-4 is provided at the right end, and a through-line through hole 4-5 is provided on the inner side.

[0037] See attached Figure 6 The variable diameter assembly 5 is provided with a left fixed ring 5-1 and a right fixed ring 5-2, fixed internal threads 5-4 and 5-5 are provided inside the two fixed rings, and a variable diameter umbrella 5-3 is provided in the middle, which adopts special flexible materials, including plastic, fiber (nylon), rubber and other organic flexible materials.

[0038] See attached Figure 6The two fixed internal threads 5-4 and 5-5 on the reducer assembly 5 are left-handed and right-handed threads respectively, and the corresponding fixed external threads 1-3 on the upper connector 1 and the fixed external threads 2-1 on the intermediate housing 2 are respectively set to be left-handed and right-handed.

[0039] Refer to the attached Figure 6 The variable diameter umbrella 5-3 on the variable diameter assembly 5 is a closed type with its left and right ends crimped into the fixing rings 5-1 and 5-2. Its thickness is designed according to the strength requirements, and its inner side can be embedded with a metal frame to increase its strength.

[0040] Refer to the attached Figure 1 The inner side of the adjusting ring 6 is provided with an internal thread, which is installed on the adjusting outer thread 4-3 of the adjusting spindle 4. Adjusting its position can change the compression extension amount of the reducer assembly.

[0041] Refer to the attached Figure 1 The upper spring 7 is arranged at the left end of the adjusting ring 6 to control the compression and tension stress of the upper reducer assembly 5, and the lower spring 8 is arranged at the right end of the adjusting ring 6 to play a regulating and buffering role.

[0042] Embodiment 2:

[0043] A device for improving hydraulic pumping efficiency and a control method thereof include a device for improving hydraulic pumping efficiency composed of an upper connector, an intermediate housing, a lower connector, an adjusting spindle, a reducing assembly, an adjusting ring, an upper spring and a lower spring.

[0044] The specific steps include: when the device is not under stress, the reducer assembly is in a compressed and extended state through the upper spring force, and the extension amount is limited by the adjustment ring; when the upper connector of the device is stretched and stressed, and the tension is greater than a certain value, the upper spring is compressed, the reducer assembly is stretched and contracted, and the outer diameter is completely lower than the outer edge of the device. When the entire tool string is at the wellhead or the vertical well section, due to the effect of its own gravity, when the cable is stretched, the reducer assembly is in a stretched and contracted state. When entering the horizontal section, the cable is not under stress, and the reducer assembly is automatically in a compressed and extended state, increasing the cross-sectional area of ​​the outer diameter of the tool string, increasing the thrust during hydraulic pumping, if the tool string pumping runs smoothly, the cable is stressed, and the reducer assembly automatically stretches and contracts. If the tool string pumping runs poorly, the cable is not stressed, and the reducer assembly automatically compresses and extends, thereby improving the hydraulic pumping efficiency. In addition, the reducer assembly of the device is made of special flexible materials, which can pass through the reducer well, and will not leave metal hard objects even if damaged, and it is quick and convenient to replace on the ground.

[0045] The left end of the upper connector is provided with an external thread and a sealing groove, four wrench holes are arranged around the middle, a fixed external thread and a sliding step are arranged at the right end, and a through hole, a spindle internal thread, a spindle sealing surface, and a spindle through hole are arranged inside.

[0046] The left end of the intermediate shell is provided with a fixed external thread, the outer side of the shell is provided with four wrench holes and four water grooves around, the inner side of the right end is provided with an internal thread and a sealing surface, and the inner side of the left end is provided with a sliding through hole, a spindle through hole, and an adjustment hole.

[0047] The left end of the lower connector is provided with an external thread and a sealing groove, four wrench holes are arranged around the middle outer side, the right end is provided with an external thread and a sealing groove, and the inner side is provided with a spindle movable through hole.

[0048] The left end of the adjustment spindle is provided with an external thread and a sealing groove, the middle of the outer side is provided with an adjustment external thread, the right end is provided with a sealing groove, and the inner side is provided with a through-line through hole.

[0049] The variable diameter assembly is provided with a left fixed ring and a right fixed ring, the inner sides of the two fixed rings are provided with fixed internal threads, and a variable diameter umbrella is provided in the middle, and special flexible materials are used, including organic flexible materials such as plastic, fiber (nylon), and rubber.

[0050] The two fixed internal threads on the reducer assembly are left-handed and right-handed threads respectively, and the corresponding fixed external threads on the upper connector and the fixed external threads on the intermediate housing are left-handed and right-handed respectively.

[0051] The variable diameter umbrella on the variable diameter assembly is a closed type with both left and right ends pressed into the fixed ring. Its thickness is designed according to the strength requirement, and a metal frame can be embedded inside to increase its strength.

[0052] The inner side of the adjusting ring is provided with an internal thread, which is installed on the adjusting external thread of the adjusting spindle. The compression extension amount of the reducing assembly can be changed by adjusting the position of the adjusting ring.

[0053] The upper spring is arranged at the left end of the adjusting ring to control the compression and tension stress of the upper reducer assembly, and the lower spring is arranged at the right end of the adjusting ring to play an adjusting and buffering role.

[0054] The method of using the present invention is as follows: the left end of the upper connector 1 can be equipped with a connecting cable, a magnetic locator or a hand release device, the adjusting mandrel 4 is sleeved with an adjusting ring 6 and an upper spring 7, and is sleeved into the intermediate shell 2, connected to the upper connector 1 together, and tightened, the reducing assembly 5 is pre-arranged on the step between the upper connector 1 and the intermediate shell 2, the lower spring 8 is inserted, the upper and lower connectors 3 are driven, and the adjusting mandrel 4 passes through the lower connector 3, the two fixing rings 5-1 and 5-2 of the reducing assembly 5 are simultaneously driven into the fixed external threads 1-3 and 2-1 at the left and right ends, and the right end of the lower connector 3 can be matched with a perforating gun string.

[0055] The working principle of the present invention is:

[0056] When the device is not under stress, the reducer assembly is in a compressed and extended state through the upper spring force, and the extension amount is limited by the adjustment ring; when the upper connector of the device is stretched and stressed, and the tension is greater than a certain value, the upper spring is compressed, the reducer assembly is stretched and contracted, and the outer diameter is completely lower than the outer edge of the device. When the entire tool string is at the wellhead or vertical well section, due to its own gravity, when the cable is stretched, the reducer assembly is in a stretched and contracted state. When entering the horizontal section, the cable is not stressed, and the reducer assembly is automatically in a compressed and extended state, increasing the cross-sectional area of ​​the outer diameter of the tool string, increasing the thrust during hydraulic pumping. If the tool string pumping runs smoothly and the cable is stressed, the reducer assembly automatically stretches and contracts. If the tool string pumping runs poorly and the cable is not stressed, the reducer assembly automatically compresses and extends, thereby improving the hydraulic pumping efficiency. In addition, the reducer assembly of the device is made of special flexible materials, which can pass through the reducer well. Even if it is damaged, no metal hard objects will be left, and it is quick and convenient to replace it on the ground.

[0057] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A device for improving hydraulic pumping efficiency, characterized in that: It includes an upper connecting head, an intermediate shell, a lower connecting head, a reducing assembly, an adjusting spindle, an upper spring, and an adjusting ring; wherein, one end of the adjusting spindle is fixedly connected to the upper connecting head, and the other end is slidably plugged with the lower connecting head, and the middle section passes through the intermediate shell; one end of the upper connecting head is plugged into the intermediate shell, and is slidably plugged with the intermediate shell; an axial positioning step is provided in the intermediate shell, and the axial positioning step is limitedly matched with the upper connecting head; the intermediate shell is fixedly sleeved with the lower connecting head; one end of the reducing assembly is fixedly sleeved on the upper connecting head, and the other end is fixedly sleeved on the intermediate shell; the upper spring is sleeved on the adjusting spindle, and is located between the axial positioning step and the adjusting ring; the adjusting ring is threadedly connected to the middle section of the adjusting spindle, and is located in the intermediate shell, and also includes a lower spring, which is sleeved on the adjusting spindle, between the adjusting ring and the lower connecting head, The variable diameter assembly includes a left fixed ring, a right fixed ring, and a variable diameter umbrella. The left fixed ring is fixedly sleeved on the upper connecting head, and the right fixed ring is fixedly sleeved on the intermediate shell. Both ends of the variable diameter umbrella are sealed and fixedly connected to the left fixed ring and the right fixed ring respectively. The variable diameter umbrella is made of flexible material, and an elastic metal frame is embedded inside the variable diameter umbrella.

2. A device for improving hydraulic pumping efficiency according to claim 1, characterized in that: An adjustment hole is provided on the side wall of the intermediate shell.

3. The device for improving hydraulic pumping efficiency according to claim 1, characterized in that: The outer walls of the upper connecting head and the lower connecting head are provided with wrench holes arranged circumferentially.

4. The device for improving hydraulic pumping efficiency according to claim 1, characterized in that: A sliding step is provided at one end of the upper connector, the sliding step is plugged into the intermediate housing, and is in sliding sealing cooperation with the intermediate housing, and the sliding step is limitedly cooperated with the axial positioning step.

5. The device for improving hydraulic pumping efficiency according to claim 1, characterized in that: The intermediate shell is threadedly and sealingly connected to the lower connecting head.

6. The device for improving hydraulic pumping efficiency according to claim 5, characterized in that: An adjustable spindle movable through hole is arranged in the lower connecting head, and the adjustable spindle movable through hole is matched with the adjustable spindle in a sliding and sealing manner.

7. The device for improving hydraulic pumping efficiency according to claim 6, characterized in that: A through-line through hole which penetrates axially is arranged inside the adjusting spindle.

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