阅读说明：本技术 柔性旋转喷射清理工具 (Flexible rotary jet cleaning tool ) 是由 任勇强 仪忠建 刘英杰 郭云鹏 杨小涛 李进 陈晖� 郑建锋 周灏 陈雅勇 石光 于 2019-09-24 设计创作，主要内容包括：本发明公开了一种柔性旋转喷射清理工具,其包括液压丢手、多段式柔性连接节和旋转喷射器三大组成部分。其中液压丢手包括丢手上接头、丢手、剪切销钉；多段式柔性连接节包括依次连接的若干个柔性连接肘节,每个柔性连接肘节包括肘节连接部和两个肘节连接部压帽,每相邻的两个柔性连接肘节之间均通过一个连接节I彼此柔性连接；旋转喷射器包括旋转喷射器上压帽、接头、喷射器下压帽、上喷射短节、喷射短节侧喷嘴、下喷射短节、旋转磨铣齿、喷射短节下喷嘴。本发明同时兼具喷射冲孔与旋转钻进的双重功能,具有处理效率高、角度可调、不受生产套管不居中或弯曲变形影响、可安全丢手等特点。(the invention discloses a flexible rotary jet cleaning tool which comprises three major components, namely a hydraulic release, a multi-section flexible connecting joint and a rotary jet. The hydraulic releasing tool comprises a releasing tool upper joint, a releasing tool and a shearing pin; the multi-section flexible connecting joint comprises a plurality of flexible connecting toggle joints which are connected in sequence, each flexible connecting toggle joint comprises a toggle connecting part and two toggle connecting part pressing caps, and every two adjacent flexible connecting toggle joints are flexibly connected with each other through a connecting joint I; the rotary ejector comprises an upper pressing cap of the rotary ejector, a joint, a lower pressing cap of the ejector, an upper jet short section, a lateral nozzle of the jet short section, a lower jet short section, a rotary milling tooth and a lower nozzle of the jet short section. The invention has the dual functions of jet punching and rotary drilling, and has the characteristics of high processing efficiency, adjustable angle, no influence of non-centering or bending deformation of the production casing, safe releasing and the like.)

1. A flexible rotary jet cleaning tool comprises a hydraulic release, a multi-section flexible connecting joint and a rotary jet, wherein the inner cavities of the hydraulic release, the multi-section flexible connecting joint and the rotary jet are communicated and sequentially connected, the multi-section flexible connecting joint comprises a plurality of flexible connecting toggle joints which are sequentially connected, every two adjacent flexible connecting toggle joints are flexibly connected with each other through a connecting joint I, the two flexible connecting toggle joints at the head end and the tail end are respectively and correspondingly flexibly and hermetically connected with the hydraulic release and the rotary jet in a one-to-one mode, the two ends of the connecting joint I are outwards projected and are in a hollow spherical shape, the middle of the connecting joint I is in a circular tube shape, the flexible connecting toggle joints comprise toggle connecting parts and two toggle connecting part pressing caps which are in a tubular structure, the two toggle connecting part pressing caps are symmetrically and hermetically connected with the two ends of the toggle connecting part through threads, and, The other end is processed with a taper hole, the middle position of the inner cavity of the toggle joint connecting part pressing cap is also processed with a spherical hole and used for placing a hollow spherical end of the connecting joint I, and a sealing ring is arranged between the spherical hole and the hollow spherical end of the connecting joint I so as to realize flexible sealing connection between the connecting joint I and the flexible connecting toggle.

2. The flexible rotary jet cleaning tool as claimed in claim 1, wherein said hydraulic release comprises a release top sub and a release top sub with communicating inner cavities and both are sealingly connected by shear pins, one end of the release is tubular and the end of the end is formed with a ball seat for a ball drop, the other end is hollow spherical and the end is fittingly and flexibly sealingly mounted in a spherical hole of a toggle link pressure cap of the head end flexible link toggle.

3. The flexible rotary jetting tool according to claim 1, wherein the rotary jetting tool comprises an upper jetting cap, a joint, a lower jetting cap, an upper jetting nipple and a lower jetting nipple, the upper jetting cap, the joint, the lower jetting cap, the upper jetting nipple and the lower jetting nipple are communicated with each other in inner cavities and are in sealing connection, the upper jetting nipple and the lower jetting cap of the jetting tool are in threaded connection at two ends of the joint, one end of the upper jetting nipple is rotatably connected with the joint through a bearing, the other end of the upper jetting nipple is in threaded connection with the lower jetting nipple, and the lower jetting cap of the jetting tool is arranged between the joint and the upper jetting nipple so as to axially fix the joint.

4. the flexible rotary jet cleaning tool as claimed in claim 3, wherein the ejector upper pressure cap has a spherical hole formed in the middle of its inner cavity, and the aft end flexible link toggle is connected to the ejector upper pressure cap by a link II, wherein the link II is in conformity with the link I, and wherein one of the hollow spherical ends of the link II is fitted in a flexible sealing manner in a matching manner in the spherical hole of the pressure cap of one of the toggle link portions of the aft end flexible link toggle and the other hollow spherical end is fitted in a flexible sealing manner in the spherical hole of the pressure cap of the ejector.

5. The flexible rotary jetting tool of claim 3, wherein the bearing is sleeved on one end of the upper jetting nipple and is limited by a sealing ring with a limiting function.

6. The flexible rotary jet cleaning tool as claimed in claim 5, wherein one end of the lower pressure cap of the jet is connected with the joint by screw thread, and the inner wall of the other end is integrally formed with a snap ring which is arranged on the step of the outer wall of the upper jet nipple and is limited by a bearing so as to realize the axial limiting and fixing of the joint and the upper jet nipple.

7. The flexible rotary jet cleaning tool according to claim 3, characterized in that the outer walls of the upper jet nipple and the lower jet nipple are respectively provided with four jet nipple side nozzles symmetrically, one end of the lower jet nipple is connected with the upper jet nipple through a thread, the other end of the lower jet nipple is provided with a jet nipple lower nozzle, and the end is also welded with rotary milling teeth circumferentially.

Technical Field

The invention relates to the field of oil and gas field development, in particular to a flexible rotary jet cleaning tool.

Background

along with the annual increase of the number of casing damage wells of the oil field, casing taking and replacing operations are increasing day by day. In the sleeve taking and replacing operation, the problem of the cement sheath between the production sleeve and the surface sleeve which is caused by the non-centering or bending deformation of the production sleeve becomes an important factor for restricting the acceleration and the efficiency improvement of the current sleeve taking and replacing construction. At present, the known technology is that an operating team performs milling treatment on a cement sheath between a production casing and a surface casing by putting a milling barrel into the milling barrel, and because the existing milling barrel is a rigid specially-made alloy steel cylinder and cannot adjust the milling angle and the orientation according to the bending deformation of the casing and the deflection of the cement sheath, if the production casing is not centered or bent and deformed, the sleeve is easily split, the production casing is cut off or the window opening of the surface casing is caused, the subsequent construction is influenced, the engineering progress and the speed increasing and efficiency increasing of the sleeve taking and changing construction operation are restricted, and meanwhile, the construction working hours are increased and the construction cost is increased.

Disclosure of Invention

The invention aims to solve the technical problems and provide a flexible rotary jet cleaning tool which is high in treatment efficiency, adjustable in angle and good in cleaning effect.

In order to solve the technical problems, the invention adopts the following technical scheme:

a flexible rotary jet cleaning tool comprises a hydraulic release, a multi-section flexible connecting joint and a rotary jet, wherein the inner cavities of the hydraulic release, the multi-section flexible connecting joint and the rotary jet are communicated and sequentially connected, the multi-section flexible connecting joint comprises a plurality of flexible connecting toggle joints which are sequentially connected, every two adjacent flexible connecting toggle joints are flexibly connected with each other through a connecting joint I, the two flexible connecting toggle joints at the head end and the tail end are respectively and correspondingly flexibly and hermetically connected with the hydraulic release and the rotary jet, the two ends of the connecting joint I are outwards projected hollow spheres, the middle of the connecting joint I is in a circular tube shape, the flexible connecting toggle joints comprise toggle connecting parts and two toggle connecting part pressure caps which are in a tubular structure, the two toggle connecting part pressure caps are symmetrically and threadedly and hermetically connected at the two ends of the toggle connecting parts, a female buckle for connecting the toggle connecting parts is processed at one end of the, a spherical hole is further processed in the middle of the inner cavity of the toggle connecting part pressing cap and is used for placing a hollow spherical end of the connecting joint I, and a sealing ring is further arranged between the spherical hole and the hollow spherical end of the connecting joint I so as to realize flexible sealing connection between the connecting joint I and the flexible connecting toggle.

Furthermore, the hydraulic releasing hand comprises a releasing hand upper joint and a releasing hand which are communicated with each other in inner cavities and are in sealing connection through a shear pin, one end of the releasing hand is in a circular tube shape, a ball seat used for a pitching landing position is processed at the end part of the end, the other end of the releasing hand is in a hollow spherical shape, and the end is flexibly and hermetically installed in a spherical hole of a toggle joint part pressing cap of the head end flexible connecting toggle in a matching mode.

Further, rotatory sprayer includes that the inner chamber communicates with each other and seal connection's sprayer goes up presses cap, joint, sprayer to press the cap down, goes up to spray the nipple joint and sprays the nipple joint down, presses cap and sprayer to press cap threaded connection on the sprayer at the both ends of joint down, goes up to spray nipple joint one end and passes through the bearing and rotationally links together with the joint, the other end and sprays nipple joint threaded connection down, wherein the sprayer presses the cap setting down and sprays the axial fixity of nipple joint and last injection nipple joint in order to realize between nipple joint and the last injection nipple joint.

Furthermore, a spherical hole is formed in the middle of the inner cavity of the upper pressure cap of the ejector, the tail end flexible connecting toggle joint is connected with the upper pressure cap of the ejector through a connecting joint II, the connecting joint II and the connecting joint I are consistent in structure, one hollow spherical end of the connecting joint II is flexibly and hermetically arranged in the spherical hole of the pressure cap of one toggle connecting part of the tail end flexible connecting toggle joint in a matching mode, and the other hollow spherical end of the connecting joint II is flexibly and hermetically arranged in the spherical hole of the upper pressure cap of the ejector in a matching mode.

Furthermore, the bearing sleeve is arranged at one end of the upper jet nipple and is limited by a sealing ring with a limiting function.

Furthermore, one end of the injector lower pressing cap is in threaded connection with the joint, and a clamping ring is integrally formed on the inner wall of the other end of the injector lower pressing cap and is arranged on a step on the outer wall of the upper injection short section and limited by a bearing, so that the axial limiting fixation of the joint and the upper injection short section is realized.

Furthermore, the outer walls of the upper jet nipple and the lower jet nipple are respectively and symmetrically provided with four jet nipple side nozzles, one end of the lower jet nipple is in threaded connection with the upper jet nipple, the other end of the lower jet nipple is provided with a jet nipple lower nozzle, and the end of the lower jet nipple is welded with rotary milling teeth in an annular mode.

The invention has the beneficial effects that:

The invention realizes the efficient cleaning of the partially-fixed cement ring between the production casing and the surface casing by means of the dual functions of hydraulic jet punching of the sand-carrying liquid and rotary drilling of the bottom grinding shoe; when the problem of the production casing which is not centered or bent and deformed is encountered, the matched multi-section flexible connecting joint can be bent and drilled according to the bending and deformation condition of the casing; if accidents such as drilling tool burying, clamping and the like caused by collapse of a cement sheath occur in the construction process, the steel ball is thrown in to implement pressing and releasing, subsequent fishing is carried out, and the accidents are prevented from being complicated.

The tool has the dual functions of jet punching and rotary drilling, and has the characteristics of high processing efficiency, adjustable angle, no influence of non-centering or bending deformation of a production casing pipe, safe releasing and the like.

Drawings

FIG. 1 is a schematic structural view of a flexible rotary jet cleaning tool according to the present invention;

FIG. 2 is a schematic structural diagram of a hydraulic release according to the present invention;

FIG. 3 is a schematic structural view of a multi-section flexible joint according to the present invention;

FIG. 4 is a schematic view of a rotary injector according to the present invention;

FIG. 5 is a schematic view of a production casing above a run-in milling shoe milling deviated well section and a cement sheath between a surface casing;

FIG. 6 is a schematic view of a flexible rotary jet cleaning tool being lowered to clean the hardened cement rings between the casings and restore the production casings to a free state;

FIG. 7 is a schematic view of a running special tool trimming or cutting a deformed production casing of a production interval;

FIG. 8 is a schematic representation of the run-in milling shoe continuing to process the remaining production casing and the cement sheath between the surface casing.

In the figure: a-hydraulic release, B-multi-section flexible connecting joint, C-rotary injector, 1-release upper joint, 2-release, 201-ball seat, 202-sealing ring I, 203-sealing ring II, 3-shearing pin, 4-connecting joint I, 5-toggle connecting part upper pressing cap, 501-sealing ring III, 502-sealing ring IV, 6-toggle connecting part, 7-toggle connecting part lower pressing cap, 701-sealing ring V, 702-sealing ring VI, 8-connecting joint II, 9-injector upper pressing cap, 10-joint, 1001-sealing ring VII, 11-bearing, 1101-sealing ring VIII, 1102-sealing ring IX, 1103-sealing ring X, 12-injector lower pressing cap, 13-upper injection, 14-injection short joint side nozzle, 15-lower injection, 16-rotary milling tooth, and 17-injection lower nozzle.

Detailed Description

The invention is described in further detail below with reference to the following figures and detailed description:

Referring to fig. 1 to 4, the flexible rotary jet cleaning tool of the invention mainly comprises a hydraulic release A, a multi-section flexible connecting joint B and a rotary jet C. The hydraulic release A mainly comprises a release upper joint 1, a release 2 and a shearing pin 3; the multi-section flexible connecting joint B comprises a plurality of flexible connecting toggle joints which are connected in sequence, every two adjacent flexible connecting toggle joints are flexibly connected with each other through a connecting joint I4, the two flexible connecting toggle joints at the head end and the tail end are respectively and correspondingly flexibly and hermetically connected with the hydraulic release A and the rotary ejector C, and each flexible connecting toggle joint mainly comprises a toggle connecting part upper pressing cap 5, a toggle connecting part 6 and a toggle connecting part lower pressing cap 7; the rotary ejector C mainly comprises an ejector upper pressing cap 9, a joint 10, a bearing 11, an ejector lower pressing cap 12, an upper jet nipple 13, a jet nipple side nozzle 14, a lower jet nipple 15, rotary milling teeth 16, a jet nipple lower nozzle 17 and the like.

As shown in figures 1 and 2, the structure of each part of the hydraulic release A is characterized in that: the upper joint 1 of the releasing hand is made of low-carbon alloy steel by modulation processing, a trapezoidal box capable of being connected with a D48mm small-diameter oil pipe is processed in an inner cavity on one side of the upper joint, a round hole for placing and fixing the releasing hand 2 is processed in an inner cavity on the other side of the upper joint, a through hole convenient for a shearing pin 3 to pass through is symmetrically processed from the side wall to the inner cavity, and the middle rest part of the upper joint 1 of the releasing hand is completely penetrated through by a round hole with a smaller diameter along the central axis; a through round hole is processed in the inner part of the releasing gadget 2 along the axial direction, the outer side of one end of the releasing gadget is in a circular tube shape, the outer side of the other end of the releasing gadget is in a hollow ball shape, a ball seat 201 for putting a ball in place is processed on the inner wall of one side of the outer side of the circular tube shape, a pin hole for fixing a shearing pin 3 and an annular sealing ring groove for placing a sealing ring I202 and a sealing ring II 203 are respectively processed on the outer side wall of the releasing gadget, and a sealing ring I202 and a sealing ring II 203 are; the upper joint 1 and the lower joint 2 of the releasing gadget are connected into a whole through a shear pin 3.

As shown in fig. 1 and 3, the multi-section flexible connecting joint B can be integrally connected by tens or even tens of flexible connecting toggle joints processed and manufactured by low-carbon special alloy steel according to the requirements of site construction, and each flexible connecting toggle joint is characterized in that: the connecting joint I4 is characterized by a structure with thick two ends and thin middle, and both ends of the connecting joint I4 are hollow spheres and the middle is tubular; the upper pressing cap 5 of the toggle connecting part is of a tubular structure with a through hole in the middle, a female buckle used for connecting the toggle connecting part 6 is processed at one end of an inner cavity of the upper pressing cap, a conical hole is processed at the other end of the inner cavity of the upper pressing cap, a spherical hole used for placing a hollow spherical end of a connecting joint I4 is processed in the middle of the inner cavity, a sealing ring groove specially used for placing a sealing ring III 501 and a sealing ring IV 502 is processed in the middle of the inner cavity, and the sealing ring III 501 and the sealing ring; the toggle joint connecting part 6 is a tubular structure with thin two ends and thick middle, and male buckles for connecting the upper pressing cap 5 of the toggle joint connecting part and the lower pressing cap 7 of the toggle joint connecting part are respectively processed at the two ends of the toggle joint connecting part; the structure of the lower pressing cap 7 of the toggle joint part is basically consistent with that of the upper pressing cap 5 of the toggle joint part, one end of the inner cavity of the lower pressing cap is provided with a female buckle for connecting the toggle joint part 6, the other end of the inner cavity is provided with a tapered hole, the middle of the inner cavity is provided with a spherical hole for placing a hollow spherical end of the connecting joint I4, a sealing ring groove for specially placing a sealing ring V701 and a sealing ring VI 702 is formed, and the sealing ring V701 and the sealing ring VI 702 are placed in the sealing ring groove. The multi-section flexible connecting joint B is connected between a hydraulic release A and a rotary ejector C, specifically, a hollow spherical end of a release 2 in the hydraulic release A is flexibly and hermetically arranged in a spherical hole of a pressing cap 5 on a toggle connecting part of a head end flexible connecting toggle in a matching manner, a tail end flexible connecting toggle is flexibly and hermetically connected with the rotary ejector C through a connecting joint II 8, wherein the connecting joint II 8 and the connecting joint I4 have the same structure and shape and are structurally characterized by being thick at two ends and thin in the middle, one hollow spherical end of the connecting joint II 8 is matched and arranged in a spherical hole of a pressing cap 7 on a toggle connecting part of the tail end flexible connecting toggle, and the other hollow spherical end is matched and arranged in a spherical hole formed on the rotary ejector C.

As shown in fig. 1 and 4, the rotary injector C is characterized in that: the rotary ejector C body is made of medium-high carbon special alloy steel, each nozzle of the rotary ejector C body is mainly made of special hard alloy, the upper pressing cap 9 of the ejector is of a short cylindrical structure with a hollow inner part, a female buckle for connecting a connector 10 is machined in one side of the upper pressing cap, a 45-degree annular chamfer is turned on the outer part of the other side of the upper pressing cap, a spherical hole for placing a hollow spherical end of a connecting joint II 8 is machined in the middle of the upper pressing cap, a sealing ring groove for placing a sealing ring VII 1001 is machined, and the sealing ring VII 1001 is placed; the connector 10 is also in a short sleeve-shaped structure in appearance, a male buckle used for connecting an upper pressure cap 9 of the ejector is turned on the outer side of one end of the connector, a male buckle used for connecting a lower pressure cap 12 of the ejector is machined on the outer side of the other end of the connector, one end of the inner cavity of the connector is used for placing the bearing 11, the inner part of the inner cavity of the connector is in a step shape, the inner diameter of the inner cavity of the connector is larger, the inner diameter of the inner cavity of the connector is smaller, the inner diameter of the other end of the connector is close to the connecting joint II 8, gaps on two sides of the bearing 11 are plugged through a sealing; the lower ejector pressing cap 12 is a female buckle with 45-degree chamfers turned on two sides and internally processed for connecting the joint 10, one end of the lower ejector pressing cap 12 is in threaded connection with the joint 10, a clamping ring is integrally formed on the inner wall of the other end of the lower ejector pressing cap, and the clamping ring is arranged on a step on the outer wall of the upper ejector short section 13 and limited by a bearing 11; a trapezoidal buckle for connecting a lower injection nipple 15 is processed on the outer side of one end of an upper injection nipple 13, two layers of injection nipple side nozzles 14 are further processed at the end of the upper injection nipple 13, each layer of injection nipple side nozzles 14 form 180 degrees, a step for connecting an injector lower pressing cap 12 is processed on the outer side of the other end of the upper injection nipple 13, an annular groove for placing a bearing 11 is processed, a sealing ring groove for placing a sealing ring VIII 1101 is cut, the sealing ring VIII 1101 is placed, the sealing ring VIII 1101 has a limiting function and can realize axial limiting and fixing of the bearing 11, the bearing 11 is arranged on one side of the step of the upper injection nipple 13, a clamping ring of the injector lower pressing cap 12 can be limited on the step of the upper injection nipple 13, and finally axial limiting and fixing of a joint 10 and the upper injection nipple 13 are realized; the lower jet nipple 15 is a short pipe-shaped structure with openings at two sides with different diameters, a female buckle for connecting the upper jet nipple 13 is processed at one side of the lower jet nipple, a jet nipple lower nozzle 17 is processed at the other side of the lower jet nipple, a rotary milling tooth 16 is welded at the annular direction of the lower jet nipple lower nozzle, two layers of jet nipple side nozzles 14 are processed at the middle part of the lower jet nipple, and the jet nipple side nozzles 14 on each layer form 180 degrees.

the invention is realized by the following steps:

firstly, with reference to the tool structure shown in fig. 2, 3 and 4, the assembly of the hydraulic release a, the multi-section flexible joint B and the rotary injector C is completed separately as follows:

according to the figure 2, firstly, a sealing ring I202 and a sealing ring II 203 are sleeved in an annular sealing ring groove on one side of a ball seat 201 of a releasing sub 2 and are inserted into an inner cavity of a releasing sub 1, and then the releasing sub 1 and the releasing sub 2 are connected into a whole through a shearing pin 3, so that the hydraulic releasing sub A is assembled.

according to the figure 3, the hollow ball ends of the connecting joint I4 and the connecting joint II 8 are respectively arranged in the upper pressure cap 5 and the lower pressure cap 7 of the toggle connecting part, the inner cavities of the upper pressure cap 5 and the lower pressure cap 7 of the toggle connecting part are respectively provided with the sealing ring III 501, the sealing ring IV 502, the sealing ring V701 and the sealing ring VI 702, then the upper pressure cap 5 and the lower pressure cap 7 of the toggle connecting part are connected with the toggle connecting part 6 through screw threads, the assembly of a single flexible connecting toggle is completed, the number of the required flexible connecting toggles is estimated according to the actual length of the non-centered or bending deformation section of the underground production casing, the connection of the corresponding number of the flexible connecting toggles is carried out according to the figure 3, and the assembly of the multi-section flexible connecting joint B is completed.

According to the figure 4, firstly, the hollow ball end of the connecting joint II 8 is arranged in the inner cavity of the upper pressure cap 9 of the ejector, a seal ring VII 1001 is pressed in a seal ring groove in the inner cavity of the upper pressure cap 9 of the ejector, the upper pressure cap 9 of the ejector is connected with the joint 10 through a screw thread, the lower pressure cap 12 of the ejector is placed at the corresponding position of the upper jet nipple 13, a bearing 11 is placed in an annular groove at the corresponding end of the upper jet nipple 13, a seal ring VIII 1101 is pressed in the seal ring groove, then the lower pressure cap 12 of the ejector is connected with the joint 10 through the screw thread, the upper jet nipple 13 is connected with the joint 10 through the bearing 11, a lower jet nipple 15 with a jet nipple side nozzle 14, a rotary milling tooth 16 and a jet nipple lower nozzle 17 is connected with the upper jet nipple 13 through the screw thread, and the screw thread is tightened, so that the assembly of the rotary ejector C is completed.

then, according to the tool string structure shown in fig. 1, the hydraulic release A, the multi-section flexible connecting joint B and the rotary ejector C are connected one by one, and the connection of the flexible rotary jet cleaning tool suitable for the cementing cement ring between the shallow casings is completed.

As shown in fig. 5 to 8, the basic construction process flow based on the flexible rotary jet cleaning tool suitable for the cementing cement sheath between shallow casings is as follows:

(1) Carrying out casing milling on a cement sheath between a production casing above a deviated well cementation section and a surface casing by using a drill stem with a casing milling shoe, and observing a return product at a ground outlet and the casing milling footage condition in the casing milling process;

(2) If scrap iron returns from an outlet on the ground and the footage of a milling shoe is suddenly slowed down in the milling process, the situation that the milling is performed to a well section with a production casing not in the middle or a bending deformation well section can be judged, at the moment, a drill rod and a milling casing carried by the drill rod are required to be lifted out, a special D48mm small-diameter oil pipe is used for connecting the tool string to the lower end of the oil pipe, the oil pipe is adopted for conveying the tool string into the well and flushing the tool string while conveying the tool string to the upper part of a residual cement ring in the milling operation, the discharge capacity is increased to drive the flexible rotary jet cleaning tool to rotate, and jet, drilling and grinding cleaning are performed on the residual cement ring between the production casing and the surface casing;

(3) After cleaning the cement ring segment between the production casing and the surface casing, correspondingly putting a special tool in to trim or cut off the deformed production casing of the production well segment to expose the cement ring between the remaining production casing and the surface casing in order to ensure the implementation of subsequent milling operation;

(4) After the steps are completed, the drill stem can be adopted to carry the milling shoe to continue to process the remaining cement sheath between the production casing and the surface casing until the cement sheath between the production casing and the surface casing is thoroughly cleaned.

In summary, the present invention is not limited to the above-mentioned embodiments, and those skilled in the art can propose other embodiments within the technical teaching of the present invention, but these embodiments are included in the scope of the present invention.