Double-circulation scrap collector for well repair

Abstract

The utility model relates to the technical field of oil and gas field well repair operation tools, in particular to a double-circulation scrap collector for well repair. Comprising an upper connector, an outer pipe, an inner pipe and a collecting system, the upper connector is connected with the outer pipe and the inner pipe to form an annular cavity, an inlet hole is formed in the top of the inner pipe and communicated with the annular cavity, outlet nozzles are distributed on the pipe wall and connected with the outer pipe in a sealed mode, and a sliding sleeve controls a fluid path through vertical movement in the inner pipe; during reverse circulation, the sliding sleeve moves downwards to open the inlet hole and the outlet nozzle, an annular cavity and inclined hole loop is formed, the lower end of the collecting pipe is closed through a conical cover, centrifugal separation of chippings is accelerated through built-in spiral blades, solid-liquid graded sedimentation is achieved through an outer wall conical ring set through a gradually-shrinking structure, and the chippings enter the collecting pipe to be stored through the outlet hole. The connecting sleeve and the lower connector fix the collecting pipe, and the annular cavity of the collecting pipe is in clearance fit with the conical ring to complete multi-stage filtration. According to the design, a double-circulation mode is achieved through sliding sleeve position switching, and chippings are efficiently collected according to the fluid dynamics principle.

Description

TECHNICAL FIELD

[0001] The utility model relates to oil and gas field workover operation tool technical field, concretely relates to the dual circulation chip collector for workover. BACKGROUND

[0002] Metal chips, rock fragments and the like produced in workover operation are collectively referred to as chips, which are prone to sedimentation in the annulus of the wellbore, blocking the circulation channel of the workover fluid, causing problems such as sticking and pump failure, and seriously threatening the safety of construction. The existing chip collection device needs to be installed or replaced manually after the pump is stopped, resulting in interruption of operation, increasing the risk of well control and time cost. The traditional collection device has a fixed structure and cannot dynamically adjust the collection capacity according to the amount of chips, and it is difficult to be compatible with different well diameters and workover fluid parameters. The use of drilling, grinding and milling technology in ultra-deep wells is extremely risky, and the feeling of sticking is delayed, causing the drill pipe to break. SUMMARY

[0003] The main purpose of the utility model is to provide a dual circulation chip collector for workover, which can automatically switch the circulation path and dynamically collect chips without stopping the pump. It solves the problem of interruption of construction and low chip removal efficiency in the prior art.

[0004] To achieve the above purpose, the technical scheme provided by the utility model is:

[0005] The dual circulation chip collector for workover comprises an upper joint, an outer pipe fixed at the lower end of the upper joint, an inner pipe fixed and sealed in the outer pipe below the upper joint, an annular cavity provided between the inner pipe and the outer pipe, a hole provided at the upper end of the inner pipe and communicating with the annular cavity, a plurality of outlets fixed on the inner pipe, the outlets communicating with the inner pipe, the outlets being fixed and sealed with the outer pipe, the outlets communicating with the outside of the outer pipe, a plurality of inclined holes provided on the outer pipe below the outlets, the outlet end of the inclined hole being inclined downward, the inlet end of the inclined hole communicating with the annular cavity, a sliding sleeve provided in the inner pipe, the sliding sleeve being in sealing contact with the inner side of the inner pipe, the sliding sleeve blocking the hole at the upper part, the sliding sleeve blocking the outlets at the lower part, an opening provided on the sliding sleeve above the outlets, the hole communicating with the annular cavity and the opening communicating with the outlets when the sliding sleeve moves downward to the lower stop point in the inner pipe, the lower end of the outer pipe being fixed and sealed with a lower pipe through a connecting sleeve, a lower joint being fixed and sealed in the lower end of the lower pipe, a collection pipe being installed in the lower pipe between the lower joint and the connecting sleeve, an annular cavity being provided between the outer side of the collection pipe and the inner side of the lower pipe, a conical cover being fixedly connected to the lower end of the collection pipe, the conical cover blocking the lower end of the collection pipe, helical blades being fixed on the inner wall of the collection pipe, a plurality of conical rings being fixedly arranged on the outer side of the collection pipe along the axial direction, the diameter of the upper end of the conical ring being larger than that of the lower end, a gap being provided between the outer edge of the upper end of the conical ring and the inner edge of the lower pipe, and an outlet hole being provided on the collection pipe above the conical ring.

[0006] Specifically, a plurality of mounting rods are fixed to the upper end and the lower end of the collection pipe, the mounting rods above abutting against the lower end of the connecting sleeve, and the mounting rods below abutting against the upper end of the lower joint.

[0007] Specifically, the lower end of the cone cover is a pointed end.

[0008] Specifically, the upper end of the sliding sleeve is fixedly connected with the upper joint through a shear pin.

[0009] Specifically, the upper end of the sliding sleeve is provided with a conical surface, and the valve ball is located behind the conical surface of the upper end of the sliding sleeve, and the valve ball is in sealing contact with the upper end of the sliding sleeve.

[0010] Specifically, the lower joint is connected with the lower pipe through an anti-back-off ring, and the lower pipe is connected with the connecting sleeve through the anti-back-off ring.

[0011] Compared with the prior art, the utility model has the beneficial effects that:

[0012] 1. The heating double circulation mode of the double circulation debris collector for well repair can be seamlessly switched, and the operation continuity is significantly improved. Through the linkage design of the sliding sleeve and the valve ball, automatic switching of normal circulation and reverse circulation is realized. When normal circulation, the sliding sleeve blocks the inlet hole and the outlet nozzle, the workover fluid directly passes through the drilling tool, and the conventional operation is maintained. When reverse circulation, the valve ball triggers the sliding sleeve to descend, releases the annular cavity and the inclined hole passage, and forms an efficient debris carrying path from the outer annulus downward to the inner pipe upward. Without stopping the pump or manual intervention, the well control risk and efficiency loss caused by stopping the pump in the traditional device are avoided, and it is especially suitable for complex working conditions in ultra-deep wells.

[0013] 2. Dynamic grading collection system, improve the efficiency and capacity of debris treatment. The collection pipe combines spiral blades, conical rings and negative pressure adsorption technology to realize multi-stage separation and capacity self-adaptation. Large particle debris directly settles at the top of the collection pipe due to gravity; the spiral blades drive the workover fluid to rotate, strengthening the centrifugal sedimentation of large particles; the conical ring structure accelerates the fluid, the upper cavity forms a negative pressure, and small particles are actively extracted to the annular cavity. The grading collection mechanism, that is, large particles remain and small particles are discharged, avoids the risk of single container blockage, prolongs the continuous operation time, and adapts to the fluctuation of debris quantity in different well conditions.

[0014] 3. Modular structure design, which enhances reliability and compatibility. Anti-back-off ring: the connecting sleeve, the lower pipe and the lower joint are fixed through the anti-back-off ring to prevent loosening under high pressure impact. The two ends of the collection pipe are connected with the connecting sleeve and the lower joint through the mounting rod to ensure axial stability and avoid vibration deviation. The lower end of the cone cover is designed to be sharp to guide the smooth entry of debris into the collection pipe and reduce accumulation. The modular architecture is easy to disassemble and maintain, and is suitable for different well diameters and workover fluid parameters, reducing the cost of tool customization.

[0015] 5、Low trigger threshold operation, reduce the complexity and risk of construction. Based on the valve ball and shear pin trigger mechanism to simplify the operation process. After the valve ball is set on the sliding sleeve cone, the hydraulic pressure shears the shear pin, drives the sliding sleeve to descend to the preset position, and the action is accurate and controllable; rely on fluid pressure control throughout, without additional power source or manual adjustment, reduce the risk of human error. Suitable for high risk scenes such as high temperature and high pressure wells, high inclination wells, etc., significantly improve the safety of construction.

[0016] 5、Fluid mechanics optimized design, strengthen the efficiency of debris removal. The inclined hole of the outer tube is downwardly inclined, which guides the workover fluid to impact the bottom debris accumulation area, improves the debris suction efficiency; the annular cavity provides stable high pressure flow, the taper ring gap accelerates the fluid to form local negative pressure, and the double path cooperates to promote the debris to separate from the wellbore; the helical blade in the collection pipe induces the workover fluid to rotate, prolongs the debris residence time, and improves the centrifugal separation effect. The comprehensive fluid control technology breaks through the limitation of traditional device one-way flushing, realizes the closed-loop management of efficient debris removal and dynamic collection. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a sectional view of the collector before the valve ball is put in.

[0018] Figure 2 is a sectional view of the collector after the valve ball is put in.

[0019] Figure 3 is Figure 2 is an enlarged view of area A.

[0020] Figure 4 is Figure 2 is an enlarged view of area B.

[0021] The names of the components in the drawings are: DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0023] As Figures 1-4As shown, the dual circulation debris collector for well repair includes an upper joint 1, an outer pipe 2 fixed at the lower end of the upper joint 1, an inner pipe 3 fixed and sealed in the outer pipe 2 below the upper joint 1, an annular cavity 302 provided between the inner pipe 3 and the outer pipe 2, an inlet hole 301 provided at the upper end of the inner pipe 3 and communicating with the annular cavity 302, a plurality of outlet nozzles 304 fixed on the inner pipe 3 and communicating with the inner pipe 3, the outlet nozzles 304 being fixed and sealed with the outer pipe 2, the outlet nozzles 304 communicating with the outside of the outer pipe 2, a plurality of inclined holes 303 provided on the outer pipe 2 below the outlet nozzles 304, the outlet ends of the inclined holes 303 being inclined downward, the inlet ends of the inclined holes 303 communicating with the annular cavity 302, a sliding sleeve 4 provided in the inner pipe 3, and the sliding sleeve 4 being fixedly connected with the upper joint 1 through a shear pin at the upper end of the sliding sleeve 4. The outer side of the sliding sleeve 4 is in sealing contact with the inner side of the inner pipe 3, the sliding sleeve 4 blocks the inlet hole 301 at the upper part of the sliding sleeve 4, and the sliding sleeve 4 blocks the outlet nozzles 304 at the lower part of the sliding sleeve 4. An opening 401 is provided on the sliding sleeve 4 above the outlet nozzles 304.

[0024] A tapered surface is provided at the upper end of the sliding sleeve 4, and a valve ball 5 is seated on the tapered surface at the upper end of the sliding sleeve 4, and the valve ball 5 is in sealing contact with the upper end of the sliding sleeve 4.

[0025] After the valve ball 5 is put in, when the sliding sleeve 4 moves downward to the lower stop point in the inner pipe 3, the inlet hole 301 communicates with the annular cavity 302, and the opening 401 communicates with the outlet nozzles 304.

[0026] The lower end of the outer pipe 2 is fixedly and sealingly connected with a lower pipe 6 through a connecting sleeve 14, and the lower end of the lower pipe 6 is fixedly and sealingly connected with a lower joint 7. The lower joint 7 is connected with the lower pipe 6 through an anti-back-off ring, and the lower pipe 6 is connected with the connecting sleeve 14 through an anti-back-off ring.

[0027] A collecting pipe 8 is installed in the lower pipe 6 between the lower joint 7 and the connecting sleeve 14. Specifically, a plurality of mounting rods 12 are fixed at the upper end and the lower end of the collecting pipe 8, the mounting rods 12 at the upper part abut against the lower end of the connecting sleeve 14, and the mounting rods 12 at the lower part abut against the upper end of the lower joint 7.

[0028] An annular cavity is provided between the outer side of the collecting pipe 8 and the inner side of the lower pipe 6, a tapered cover 11 is fixedly connected to the lower end of the collecting pipe 8, and the lower end of the tapered cover 11 is a pointed end. The tapered cover 11 blocks the lower end of the collecting pipe 8, helical blades 10 are fixed on the inner wall of the collecting pipe 8, a plurality of tapered rings 9 are fixedly arranged on the outer side of the collecting pipe 8 along the axial direction of the collecting pipe 8, the upper end of each tapered ring 9 has a larger diameter than the lower end, a gap is provided between the outer edge of the upper end of the tapered ring 9 and the inner edge of the lower pipe 6, and an outlet hole 13 is provided on the collecting pipe 8 above the tapered ring 9.

[0029] In use, the dual circulation debris collector for well repair is installed on a drill and mill pipe string, and when well fluid circulates, the well fluid passes through the dual circulation debris collector for well repair and the drill and mill pipe string, and is then discharged upward from the annular cavity between the drill and mill pipe string and the wellbore 15.

[0030] When the debris needs to be collected, the valve ball 5 is put into the drill and mill pipe string, and after the valve ball 5 is seated on the upper end of the sliding sleeve 4, the sliding sleeve 4 is blocked, under the action of the pressure of the workover fluid, the shear pin is sheared, and then the sliding sleeve 4 and the valve ball 5 move downward.

[0031] When the sliding sleeve 4 and the valve ball 5 move to the lower dead point, the inlet hole 301 is communicated with the annular cavity 302, and the opening hole 401 is communicated with the outlet nozzle 304. The workover fluid above the valve ball 5 is discharged to the space between the wellbore 15 and the double circulation debris collector for workover through the inlet hole 301, the annular cavity 302 and the inclined hole 303, and then moves downward. The workover fluid in the wellbore 15 below the drill and mill pipe string carries the debris into the lower joint 7, and then moves upward.

[0032] The workover fluid carrying the debris continues to move upward in the annular cavity between the collecting pipe 8 and the lower pipe 6 under the guidance of the conical cover 11, and then enters the sliding sleeve 4 below the valve ball 5 through the connecting sleeve 14 after passing through the annular cavity between the collecting pipe 8 and the lower pipe 6. The workover fluid carrying the debris in the sliding sleeve 4 below the valve ball 5 moves upward between the double circulation debris collector for workover and the wellbore 15 through the opening hole 401 and the outlet nozzle 304, and is discharged to the ground.

[0033] When the workover fluid carrying the debris moves upward above the collecting pipe 8, the large-particle debris precipitates into the collecting pipe 8 under the action of gravity.

[0034] During the upward movement of the workover fluid carrying the debris in the annular cavity between the collecting pipe 8 and the lower pipe 6, when the workover fluid carrying the debris flows through the space between the upper end of the conical ring 9 and the lower pipe 6, the flow rate increases, so that a negative pressure is generated in the annular cavity part between the collecting pipe 8 and the lower pipe 6 above the conical ring 9. Under the action of the negative pressure, the workover fluid in the collecting pipe 8 can carry the small-particle debris out of the outlet hole 13 into the collecting pipe 8 and be discharged with the upward movement of the workover fluid between the lower pipe 6 and the collecting pipe 8, and the large-particle debris remains in the collecting pipe 8.

[0035] During the process that the workover fluid carrying the small-particle debris in the collecting pipe 8 is discharged from the outlet hole 13, the workover fluid in the collecting pipe 8 circulates from inside to outside. Under the guidance of the helical blade 10, the workover fluid in the collecting pipe 8 rotates, and under the action of centrifugal force, the large-particle debris can be centrifugally settled in the collecting pipe 8, so that the collection efficiency of the large-particle debris is improved.

[0036] The above merely describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A dual circulation debris collector for workover operations, comprising an upper sub (1) having a lower end to which an outer tube (2) is fixed, characterized in that, The outer pipe (2) below the upper joint (1) is fixedly sealed with the inner pipe (3), and the annular cavity (302) is arranged between the inner pipe (3) and the outer pipe (2). The upper end of the inner pipe (3) is provided with the inlet hole (301) communicated with the annular cavity (302). A plurality of outlet nozzles (304) are fixedly arranged on the inner pipe (3) and communicated with the inner pipe (3). The outlet nozzles (304) are fixedly and sealingly connected with the outer pipe (2) and communicated with the outside of the outer pipe (2). A plurality of inclined holes (303) are arranged on the outer pipe (2) below the outlet nozzles (304). The outlet end of the inclined hole (303) is inclined downward, and the inlet end of the inclined hole (303) is communicated with the annular cavity (302). The sliding sleeve (4) is arranged in the inner pipe (3) and sealingly contacts the inner side of the inner pipe (3). The sliding sleeve (4) blocks the inlet hole (301) at the upper part and blocks the outlet nozzle (304) at the lower part. The sliding sleeve (4) is provided with the opening (401) above the outlet nozzle (304). When the sliding sleeve (4) moves downward to the lower stop point in the inner pipe (3), the inlet hole (301) is communicated with the annular cavity (302), and the opening (401) is communicated with the outlet nozzle (304). The lower end of the outer pipe (2) is fixedly and sealingly connected with the lower pipe (6) through the connecting sleeve (14). The lower end of the lower pipe (6) is fixedly and sealingly connected with the lower joint (7). The collecting pipe (8) is arranged in the lower pipe (6) between the lower joint (7) and the connecting sleeve (14). The annular cavity is arranged between the outer side of the collecting pipe (8) and the inner side of the lower pipe (6). The lower end of the collecting pipe (8) is fixedly connected with the conical cover (11). The conical cover (11) blocks the lower end of the collecting pipe (8). The helical blade (10) is fixedly arranged on the inner wall of the collecting pipe (8). A plurality of conical rings (9) are fixedly arranged on the outer side of the collecting pipe (8) along the axial direction. The diameter of the upper end of the conical ring (9) is greater than that of the lower end. The gap is arranged between the outer side of the upper end of the conical ring (9) and the inner edge of the lower pipe (6). The outlet hole (13) is arranged on the collecting pipe (8) above the conical ring (9).

2. The dual circulation debris collector for well servicing as defined in claim 1, wherein, The upper end and the lower end of the collecting pipe (8) are fixedly provided with a plurality of mounting rods (12). The upper mounting rod (12) abuts against the lower end of the connecting sleeve (14), and the lower mounting rod (12) abuts against the upper end of the lower joint (7).

3. The dual circulation debris collector for well servicing as defined in claim 1, wherein, The lower end of the conical cover (11) is a pointed end.

4. The dual circulation debris collector for well servicing as defined in claim 1, wherein, The upper end of the sliding sleeve (4) is fixedly connected with the upper joint (1) through the shear pin.

5. The dual circulation debris collector for well servicing as defined in claim 1, wherein, The upper end of the sliding sleeve (4) is provided with a conical surface. The valve ball (5) is arranged behind the conical surface of the upper end of the sliding sleeve (4) and sealingly contacts the upper end of the sliding sleeve (4).

6. The dual circulation debris collector for well servicing of claim 1, wherein, The lower joint (7) is connected with the lower pipe (6) through the anti-inverted ring, and the lower pipe (6) is connected with the connecting sleeve (14) through the anti-inverted ring.

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