A bridge packer

Abstract

The present invention discloses a bridge packer, comprising an upper central pipe, a flow guide joint and a lower central pipe connected in sequence, an annulus casing connected to the flow guide joint is sleeved on the outer wall of the upper central pipe, and the gap between the two constitutes an upper annulus channel, an upper joint and a rubber sleeve assembly are sleeved in sequence on the outer wall of the annulus casing, and a slip assembly is sleeved on the outer wall of the lower central pipe. The flow guide joint bridges the waterway and the oilway, and has an upper annulus channel for oil-water separation, so that the water layer passes through the oil layer and is injected below the oil layer, forming a construction process of lower injection and upper production, effectively filling the deficit of the oil layer, increasing the total amount of remaining oil produced, and reducing the investment cost of each well. The mechanical anchoring effect of the slip effectively reduces the S-shaped bending of the pipe string, and cooperates with the sealing rubber sleeve to reduce the influence of pipe string creep generated when the deep well pump is working.

Description

Technical Field

[0001] The invention relates to the technical field of oil field production process equipment, in particular to a bridge packer. Background Art

[0002] Packers are widely used in drilling, cementing, testing, and completion operations, primarily for stratifying oil production. The RFY211-114 packer, a modified version of the Y111 packer with a mechanical anchoring principle, not only meets industry standards for packers, but also boasts an inner central tube flow rate of at least 35 cubic meters per day and an annular flow rate of 70 cubic meters per day between the inner and outer central tubes. Because oil reservoirs are located thousands of meters or more underground and contain large reserves, significant reservoir deficits remain after a certain level of crude oil has been extracted, making it difficult to recover the remaining oil. To maximize the recovery of oil from the reservoir, the current industry practice is to inject water into the upper layers of the reservoir to fill the deficit and maintain sufficient production pressure for the remaining oil. This process is known as top-injection and bottom-out recovery. However, this process suffers from the presence of a water layer above the oil layer, making it less than ideal for filling the reservoir deficit and making recovery of the remaining oil difficult. Summary of the Invention

[0003] In response to the above-mentioned problems, the present invention aims to provide a bridge packer, comprising an upper central pipe, a flow guide joint, and a lower central pipe connected in sequence, wherein an annulus casing connected to the flow guide joint is sleeved on the outer wall of the upper central pipe, and the gap between the two constitutes an upper annulus channel, an upper joint and a rubber sleeve assembly are sleeved on the outer wall of the annulus casing in sequence, the end of the upper central pipe away from the flow guide joint is inserted into the upper joint, a first annulus liquid inlet hole communicating with the annulus casing is opened on the side wall of the upper joint, and a slip assembly is sleeved on the outer wall of the lower central pipe. The bridge packer designed with the above-mentioned components changes the current construction process of upper injection and lower production to a production process of lower injection and upper production, thereby increasing the recovery of residual oil.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows: a bridge seal, characterized in that: it includes an upper center pipe, a guide joint and a lower center pipe connected in sequence, an annulus casing connected to the guide joint is sleeved on the outer wall of the upper center pipe, and the gap between the two constitutes an upper annulus channel, an upper joint and a rubber sleeve assembly are sleeved on the outer wall of the annulus casing in sequence, the upper center pipe is inserted into the upper joint at one end away from the guide joint, a first annulus liquid inlet hole communicating with the annulus casing is opened on the side wall of the upper joint, and a cava assembly is sleeved on the outer wall of the lower center pipe.

[0005] Preferably, the flow guide joint is provided with diversion holes parallel to its axis along its circumferential spacing, and the two ends of the diversion holes are connected with the upper annular channel and the lower center pipe in sequence; an axial liquid inlet hole is provided on the axis of the flow guide joint, and a second annular liquid inlet hole connected with the axial liquid inlet hole is provided along the radial spacing of the flow guide joint.

[0006] Preferably, the inner wall of the upper joint is provided with a first shoulder, a casing seat is provided on the side of the first shoulder away from the rubber cylinder assembly, and the first shoulder is used to limit it in one direction, and the end of the annular casing is threadedly connected to the inner wall of the casing seat.

[0007] Preferably, the lower central tube is provided with a protrusion at one end away from the diversion joint, a liquid outlet pipe is nested inside the protrusion, and the liquid outlet pipe runs through the slip assembly.

[0008] Preferably, the cava assembly includes a cava seat, a positioning cylinder is provided between the cava seat and the diversion joint, a shear pin is provided between the positioning cylinder and the outer wall of the lower center tube, the liquid outlet pipe passes through the cava seat, a movable sleeve is provided with a cava on the liquid outlet pipe, one end of which is abutted against the top of the raised portion, a hanging hole for hanging the cava is provided on the cava seat, and a cava safety pin acting on the cava is provided on the cava seat.

[0009] Preferably, the overall cross-section of the diversion joint is a virtual "I"-shaped structure, which includes a support part, a first connection part and a second connection part are symmetrically and sequentially provided on both sides of the support part, and a blind hole connected to the upper center pipe end is opened in the center of the support part toward the upper joint, the blind hole is connected to the second annulus liquid inlet hole, the top of the annulus casing is connected to the inner wall of the first connection part, the end of the lower center pipe is connected to the inner wall of the second connection part, and the diversion hole runs through the support part.

[0010] Preferably, the rubber cylinder assembly includes a retaining ring mounted on the annular casing, an upper rubber cylinder seat, a rubber cylinder and a rubber cylinder retaining ring arranged at intervals, and a lower rubber cylinder seat in sequence. The retaining ring is flush with the end of the upper joint close to one end of the upper rubber cylinder seat, and both of them are against the side wall of the upper rubber cylinder seat. One end of the retaining ring is against the side wall of the first shoulder.

[0011] Preferably, a second shoulder for limiting the first connecting part is provided in the lower rubber cylinder seat, a third shoulder for limiting the end of the guide joint and a fourth shoulder for limiting the lower center tube are provided in sequence in the positioning cylinder, and a fifth shoulder for limiting the cava is provided in the cava seat.

[0012] The beneficial effects of the present invention are as follows: (1) The diversion joint bridges the waterway and the oilway, and has an upper annular channel for oil-water separation, so that the water layer passes through the oil layer and is injected below the oil layer, forming a construction process of lower injection and upper production, effectively filling the oil layer deficit, increasing the total amount of remaining oil produced, and reducing the investment cost of each well. (2) After the sealing, the remaining weight of the pipe string is borne on the wellhead, and the mechanical anchoring effect of the slip is combined with the effective reduction of the S-shaped bending of the pipe string. In addition, the sealing rubber sleeve is combined with the rubber sleeve to reduce the creep effect of the pipe string generated when the deep well pump is working. (3) The packer adopts the mechanical sealing of the rubber sleeve and slip to overcome the situation where a large amount of liquid enters the oil-producing layer and causes pollution when the hydraulic packer is sealed. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of the bridge packer of the present invention.

[0014] Figure 2 For the present invention Figure 1 Enlarged view of point A.

[0015] Figure 3 For the present invention Figure 1 Enlarged view of point B.

[0016] Figure 4 For the present invention Figure 1 Enlarged view of point C.

[0017] Figure 5 For the present invention Figure 1 Enlarged view of point D.

[0018] Figure 6 For the present invention Figure 1 Enlarged view of point E.

[0019] Figure 7 This is a cross-sectional view of the internal structure of the flow guide joint of the present invention.

[0020] Figure 8 For the present invention Figure 7 Sectional view in direction A. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0022] Refer to the attached Figures 1 to 8The bridge packer shown includes an upper central pipe 3, a flow guide joint 11, and a lower central pipe 15, which are connected in sequence. An annulus casing 9 connected to the flow guide joint 11 is sleeved on the outer wall of the upper central pipe 3, and the gap between the annulus casing 9 forms an upper annulus channel 309. An upper joint 1 and a rubber sleeve assembly are sleeved on the outer wall of the annulus casing 9. The end of the upper central pipe 3, away from the flow guide joint 11, is inserted into the upper joint 1. A first annulus fluid inlet 101, which is in communication with the annulus casing 9, is formed in the side wall of the upper joint 1. A slip assembly is sleeved on the outer wall of the lower central pipe 15. The installation position of the bridge packer ensures that the flow guide joint 11 corresponds to the height of the oil-producing layer. After installation, water is injected into the upper annular channel 309 through the first annular inlet hole 101, and flows into the lower central pipe 15 through the diversion joint 11, and finally injected into the lower part of the oil layer, so that there is sufficient filling pressure at the bottom of the oil layer, ensuring that crude oil in the production layer can be effectively produced, so that oil and water are separated, interference between oil layers is resolved, the construction process of lower injection and upper production is realized, and the oil well production effect is improved. In order to further prevent interference between oil well layers, it is preferred that an O-ring 8 is provided at the contact point between the outer wall of the upper central pipe 3 and the upper joint 1 to prevent the water injected into the upper annular channel 309 from returning to the wellhead through the gap between the two, thereby reducing the water pressure at the bottom of the oil layer and affecting the effective oil production.

[0023] Specifically, the flow guide joint 11 is provided with diverter holes 102 parallel to its axis at intervals along its circumference. The two ends of the diverter holes 102 are sequentially connected to the upper annular passage 309 and the lower central pipe 15. An axial liquid inlet hole 103 is provided on the axis of the flow guide joint 11, and second annular liquid inlet holes 104 are provided along the radial intervals of the flow guide joint 11 and are connected to the axial liquid inlet hole 103. Water injected into the annular passage 309 through the second annular liquid inlet holes 104 flows directly into the lower central pipe 15 through the diverter holes 111 and ultimately into the oil layer below. Crude oil in the oil layer, on the other hand, enters the axial liquid inlet hole 103 through the multiple second annular liquid inlet holes 104 and is ultimately successfully extracted through the upper central pipe 3, thus achieving a construction process of lower-injection and upper-production.

[0024] To further facilitate the lowering of the entire packer, a first shoulder 201 is provided on the inner wall of the upper joint 1. A casing seat 2 is provided on the side of the first shoulder 201 facing away from the rubber cartridge assembly. The first shoulder 201 provides one-way positioning, and the end of the annular casing 9 is threadedly connected to the inner wall of the casing seat 2. When the entire packer is lowered, the first shoulder 201 limits the position of the casing seat 2 and the annular casing 9, thereby improving the connection strength between the upper joint 1 and the annular casing 9.

[0025] To further effectively extend the water injection depth of the packer, the lower central pipe 15 is provided with a raised portion 151 at one end away from the diversion joint 11. A liquid outlet pipe 19 is nested inside the raised portion 151. The two are preferably connected by threads, and the liquid outlet pipe 19 runs through the slip assembly. The raised portion 151 has a central protrusion and shoulders on both sides. Preferably, the ends of the liquid outlet pipe 19 abut against the shoulders of the raised portion 151, further increasing the reliability of the connection between the two. At the same time, an O-ring 8 is provided at the connection between the two to seal and prevent water from flowing out of the gap, reducing the water volume of the water injection layer and resulting in a reduction in the effective pressure of the oil layer.

[0026] To further enhance the hooking function of the slip assembly, the slip assembly includes a slip seat 20. A positioning cylinder 12 is provided between the slip seat 20 and the diversion joint 11, and a shear pin 13 is provided between the positioning cylinder 12 and the outer wall of the lower center tube 15. The liquid outlet pipe 19 passes through the slip seat 20. A slip 18 is movably sleeved on the liquid outlet pipe 19, one end of which abuts against the top of the protrusion 151. The slip seat 20 is provided with a hooking hole 2010 for the hooking of the slip 18. The center of the slip 18 is provided with a V-shaped opening 181 for easy hooking. Therefore, the hooking hole 2010 is configured to have a sloped structure 2011 on the side wall. The slip seat 20 is provided with a slip safety pin 22 that acts on the slip 18. When the slip 18 is hung, the top of the protrusion 151 acts downward on the end of the slip 18, the slip safety pin 22 breaks, and the slip 18 moves downward relative to the slip seat 20. The hanging hole 201 with the inclined structure 2011 provides strong support for the slip 18 with the V-shaped opening 181, so that it can be hung smoothly, reducing the S-shaped bending of the oil pipe string.

[0027] In order to further improve the oil-water separation function of the flow guide joint 11, the overall cross-section of the flow guide joint 11 is a virtual "I"-shaped structure, which includes a support portion 111, and a first connecting portion 112 and a second connecting portion 113 are symmetrically and sequentially provided on both sides of the support portion 111, and a blind hole 114 connected to the end of the upper center pipe 3 is opened in the center of the support portion 111 toward the upper joint 1, and the blind hole 114 is connected to the second annular space liquid inlet hole 104, and the top of the annular space casing 9 and the first connecting portion are connected. The inner wall of the connecting portion 112 is connected, and the end of the lower center pipe 15 is connected to the inner wall of the second connecting portion 113. Preferably, the two connection methods are both tapered thread connections toward the support portion 111. Its function is that when the rubber sleeve assembly and the slip 18 are hung, the rubber sleeve assembly needs to be subjected to the reverse friction force of the annular casing 9 and the reverse force of the slip 18 on the lower center pipe 15. The forces at these two places are both lateral forces, which form a certain pressure on the threads at the connection. Excessive pressure will loosen the threaded connection, resulting in sealing problems. Therefore, the two places are set to be tapered thread connections, so that the force on the thread surfaces of the two is reduced, and then decomposed into the radial direction of the upper joint 1. This function is to reduce the extrusion damage of the thread surface and improve the connection reliability and sealing of the annular casing 9 and the lower center pipe 15 with the diversion joint 11.

[0028] To further enhance the connection reliability between the flow guide joint 11 and the annular casing 9 and the lower central pipe 15, the diverter hole 102 runs through the support portion 111. During use, the water injected into the upper annular channel 309 directly enters the lower central pipe 15 and the liquid outlet pipe 19 through the diverter hole 102, and is ultimately injected below the oil layer. When the amount of water injected below the oil layer increases, the pressure of the oil layer above it increases, and the water enters the blind hole 114 and the upper central pipe 3 in sequence through the second annular liquid inlet hole 104, and is ultimately pumped out of the well. This achieves the construction process of lower injection and upper production, while also achieving the effect of oil-water separation, resolving interference between oil layers, and increasing the output of the oil well.

[0029] In order to effectively use the rubber cartridge assembly for seating, the rubber cartridge assembly sequentially includes a retaining ring 5 sleeved on the annular casing 9, an upper rubber cartridge seat 4, a rubber cartridge 6 and a rubber cartridge retaining ring 7 arranged at intervals, and a lower rubber cartridge seat 10. The retaining ring 5 is flush with the end of the upper joint 1 near the upper rubber cartridge seat 4, and both are in contact with the side wall of the upper rubber cartridge seat 4. One end of the retaining ring 5 is in contact with the side wall of the first shoulder 201. When the rubber cartridge is seated, the upper joint 1 pushes the retaining ring 5 and the upper rubber cartridge seat 4 in sequence through the first shoulder 201 to squeeze and expand the rubber cartridge 6, completing the seating of the rubber cartridge 6. The upper joint 1 moves relative to the casing seat 2 and the annular casing 9, allowing the casing seat 2 to break away from the one-way limiting effect of the first shoulder 201.

[0030] In order to further optimize the overall structure of the packer, the inner wall of the upper joint 1 is provided with a first shoulder 201 for limiting the retaining ring 5. The first shoulder 201 limits the retaining ring 5. At the same time, when the rubber cylinder seat is sealed, the upper joint 1 and the first shoulder 201 simultaneously push the upper rubber cylinder seat 4 and the retaining ring 5 downward as a whole; the lower rubber cylinder seat 10 is provided with a second shoulder 202 for limiting the first connecting part 112, which is used to limit the first connecting part 112 of the diversion joint 11, so that the diversion joint 11 cooperates with the upper joint 1 to squeeze the rubber cylinder 6 into the seat; the positioning cylinder 12 is provided with a plurality of The third shoulder 203 at the end of the joint 11 and the fourth shoulder 204 for limiting the lower central tube 15 are provided. The third shoulder 203 prevents the slips 18 from being damaged by excessive attachment and limits the travel of the diversion joint 11 and the lower central tube 15. The fourth shoulder 204 limits the backwash of the lower central tube 15 toward the wellhead when the water injection volume is excessive. The slip seat 20 is provided with a fifth shoulder 205 for limiting the position of the slips 18. Its function is to limit the travel of the liquid outlet pipe 19 and the lower central tube 15 when the slips 18 are attached, further preventing the slips 18 from being damaged by excessive attachment and losing their attachment function. An O-ring 8 is also provided at the contact point between the sidewall of the fifth shoulder 205 and the liquid outlet pipe 19 to prevent water from entering the attachment position of the slips 18 through this contact point and affecting the attachment reliability of the slips 18.

[0031] The principle of the present invention is as follows: the bridge packer is connected to the pipe string and lowered, the slip seat 20 is lowered into place to position and fix the packer as a whole, the pipe string at the top of the packer continues to be lowered, the lower central pipe 15 cuts the shear pin 13 downward, and continues to move downward. The protrusion 151 pushes the slip 18 and the liquid outlet pipe 19 downward, the slip 18 expands outward along the inclined structure 2011, and at the same time cuts the slip safety pin 22, the slip 18 hangs on the pipe wall, and the upper joint 1 continues to move downward. Push down, the second connection part 113 of the guide joint 11 is pressed against the upper limit of the third shoulder 203, and at the same time ensure that the second annular space liquid inlet hole 104 corresponds to the oil layer, and the upper joint 1 continues to push downward, and the first connection part 112 of the guide joint 11 is pressed against the second shoulder 202, limiting the lower rubber tube seat 10, and the upper joint 1 squeezes the rubber tube 6 to expand and seal it. After the sealing is completed, the wellhead maintains the pressure on the whole packer unchanged, so that the rubber tube 6 and the slip 18 are sealed and fixed.

[0032] Water injection is done by injecting water into the upper annular channel 309 through the first annular inlet hole 101, and then flowing through the diversion hole 102 of the diversion joint 11 to the lower central pipe 15 and the liquid outlet pipe 19, and finally injected into the lower part of the oil layer, so that the bottom of the oil layer has sufficient filling pressure to ensure that the crude oil in the oil layer can be effectively extracted. When the pressure below the oil layer is sufficient, the crude oil in the oil layer enters the axial inlet hole 103 through the second annular inlet hole 104, and finally is smoothly extracted through the upper central pipe 3, so that the oil and water are separated, the interference between the oil layers is resolved, the construction process of lower injection and upper extraction is realized, and the output of the remaining crude oil in the oil well is increased.

[0033] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A bridge packer, characterized in that: It comprises an upper central pipe (3), a flow guide joint (11) and a lower central pipe (15) which are connected in sequence, an annulus casing (9) connected to the flow guide joint (11) is sleeved on the outer wall of the upper central pipe (3), and the gap between the two constitutes an upper annulus channel (309), an upper joint (1) and a rubber sleeve assembly are sleeved on the outer wall of the annulus casing (9) in sequence, an end of the upper central pipe (3) away from the flow guide joint (11) is inserted into the upper joint (1), a first annulus liquid inlet hole (101) which is connected to the annulus casing (9) is opened on the side wall of the upper joint (1), and a slip assembly is sleeved on the outer wall of the lower central pipe (15); The flow guide joint (11) is provided with flow diversion holes (102) parallel to its axis along its circumferential spacing, and the two ends of the flow diversion holes (102) are connected with the upper annular passage (309) and the lower central pipe (15) in sequence; an axial liquid inlet hole (103) is provided on the axis of the flow guide joint (11), and a second annular liquid inlet hole (104) connected with the axial liquid inlet hole (103) is provided along the radial spacing of the flow guide joint (11); The diversion joint (11) corresponds to the height of the oil production layer; The overall cross-section of the flow guide joint (11) is a virtual "I"-shaped structure, comprising a support portion (111), a first connection portion (112) and a second connection portion (113) being symmetrically and sequentially arranged on both sides of the support portion (111), and an axial liquid inlet hole (103) at the center of the support portion (111) being a blind hole connected to the end of the upper center pipe (3), the top end of the annular casing (9) being connected to the inner wall of the first connection portion (112), the end of the lower center pipe (15) being connected to the inner wall of the second connection portion (113), and the diversion hole (102) penetrating the support portion (111).

2. A bridge packer according to claim 1, characterized in that: A protrusion (151) is provided at one end of the lower central tube (15) away from the flow guide joint (11), a liquid outlet pipe (19) is nested inside the protrusion (151), and the liquid outlet pipe (19) runs through the slip assembly.

3. A bridge packer according to claim 2, characterized in that: The slip assembly comprises a slip seat (20), a positioning cylinder (12) is provided between the slip seat (20) and the flow guide joint (11), a shear pin (13) is provided between the positioning cylinder (12) and the outer wall of the lower center pipe (15), the liquid outlet pipe (19) passes through the slip seat (20), a slip (18) is movably sleeved on the liquid outlet pipe (19), one end of which is abutted against the top of the protruding portion (151), a hanging hole (2010) for hanging the slip (18) is provided on the slip seat (20), and a slip safety pin (22) acting on the slip (18) is provided on the slip seat (20).

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