A cement crushing device for cementing

Abstract

A cementing and breaking device belongs to the field of oilfield well repair tools, including an upper joint, a central axis, a hydraulic cylinder, a guide sleeve, a piston, an expansion shoe, an expansion shoe seat, a connecting sleeve and an expansion cone. The upper joint is coaxially connected to the central axis, and the hydraulic cylinder, the piston, the connecting sleeve, the expansion shoe seat and the guide sleeve ring are sleeved on the central axis. The hydraulic cylinder is fixedly connected to the upper joint, and the piston limiter is set in the hydraulic cylinder. The piston, the hydraulic cylinder and the upper joint are combined to form an annular hydraulic space connected with the central water hole of the upper joint. The expansion shoe seat and the guide sleeve are arranged at the lower part of the hydraulic cylinder. A T-shaped hanging groove is opened on the expansion shoe seat, and a conical guiding surface is arranged on the outer circumference of the guide sleeve. The expansion shoe is hung on the expansion shoe seat, and the inner side surface is a conical inclined surface corresponding to the conical guiding surface structure. An expansion cone with a cone head protruding from the outer side surface is installed on the outer side surface of the expansion shoe. In production, the intensity of cementing and breaking operations can be reduced, the working cycle can be shortened, the cost consumption can be reduced, and the salvage effect and replacement efficiency of the working casing can be improved.

Description

Technical Field

[0001] The utility model relates to the field of oilfield well repairing tools, in particular to a cementing cement crushing device. Background Art

[0002] Based on the geological and environmental characteristics of offshore oil fields, the completion structure of offshore oil field production wells usually includes an outer waterproof casing, a middle technical casing and an inner working casing. Cementing cement needs to be poured between each layer of casing to stabilize the oil well structure. Since seawater and the marine geological environment are both highly corrosive to metals, the metal casing in the production well is extremely susceptible to corrosion by seawater and harmful substances. During production, the casing damaged by corrosion needs to be replaced in a timely manner, and the working casing with the thinnest thickness and exposed in the inner layer of the oil well is replaced most frequently. The replacement method of the working casing in the prior art is: first use a special drilling tool to lower the casing milling tool to mill and crush the cementing cement between the working casing and the technical casing, so that the working casing and the technical casing are separated from each other, and then use conventional drilling tools to lower the cutting tool and the salvage tool in turn, cut off the working casing in the casing milling area, and salvage the working casing to be replaced out of the well, and finally lower and connect the updated pipe body and inject cement slurry to fix it. Obviously, in the above process, the use of milling means to crush cementing cement as a whole not only has high work intensity, long working cycle, and high cost consumption, but also requires the exchange between special drilling tools and general drilling tools between milling, cutting and salvaging. There are obvious disadvantages such as low production efficiency and high labor intensity. Especially when the downhole working casing to be replaced is long, it is usually impossible to drill and mill the corresponding depth at one time due to the constraints of special drilling tools, milling tools or oil well conditions, but can only be milled, cut and salvaged in sections for multiple cycles until all the working casings of the entire length are completely removed and salvaged. This undoubtedly significantly increases the complexity of the operation process and further reduces the production efficiency of the replacement of the working casing. Therefore, it is necessary to research and develop cementing cement crushing tools based on the existing technology, improve the replacement operation process of the downhole working casing, and ensure the normal production of the oil field. Utility Model Content

[0003] The purpose of the utility model is to provide a cementing cement crushing device, which is used in the replacement operation of the working casing in offshore oil fields, improves the working casing replacement operation process, reduces the operation intensity, shortens the working cycle, reduces cost consumption, and improves production efficiency.

[0004] A cementing and breaking device, comprising: an upper joint, a central axis, a hydraulic cylinder, a guide sleeve, a piston, an expansion shoe, an expansion shoe seat, a connecting sleeve and an expansion cone; the upper joint is coaxially connected to the central axis up and down, the upper end of the upper joint is provided with a connecting structure for connecting to a drill pipe of a drilling tool, the lower end of the central axis has a conical guiding head for guiding the downhole stroke of the central axis, the hydraulic cylinder, the piston, the connecting sleeve, the expansion shoe seat and the guide sleeve are respectively correspondingly sleeved on the central axis; the hydraulic cylinder is fixedly connected to the upper joint and maintains a radial spacing with the central axis, the piston limiter is embedded in the hydraulic cylinder, and at the same time, respectively forms a corresponding match with the central axis and the hydraulic cylinder in the radial direction and can move axially along the central axis, the piston, the hydraulic cylinder and the upper joint are combined to form a sealed annular hydraulic space, and the annular hydraulic space is connected to the upper joint through a liquid flow hole opened on the central axis. The center water eye of the hydraulic cylinder is connected; the expansion shoe seat and the guide sleeve are correspondingly arranged in sequence at the lower part of the hydraulic cylinder, wherein the expansion shoe seat is connected to the piston through the connecting sleeve, and the guide sleeve is fixedly connected to the central axis, and a plurality of T-shaped hanging grooves are opened on the expansion shoe seat, and the T-shaped hanging grooves are evenly distributed on the circumferential section of the expansion shoe seat, and a conical guiding surface is arranged on the outer circumference of the guide sleeve; the expansion shoe is a strip plate body, and a T-shaped hanging joint is provided at the upper end. The T-shaped hanging joint can be cooperated and embedded in the T-shaped hanging groove so that the expansion shoe is correspondingly hung on the expansion shoe seat and the shoe can be kept radially movable relative to the expansion shoe seat 7, the inner side surface of the expansion shoe is a conical inclined surface, and the conical inclined surface corresponds to the conical guiding surface structure on the outer circumference of the guide sleeve and is arranged in cooperation with each other, and the expansion cone is fixedly installed on the outer side surface of the expansion shoe, and the cone head of the expansion cone protrudes from the outer side surface of the expansion shoe.

[0005] The described cement crushing device for well cementing is preferably provided with a vertically arranged track wedge on the inner side surface of the expansion shoe, and at the same time a track groove with a structure corresponding to the track wedge is opened on the outer circumferential surface of the guide sleeve. The expansion shoe is connected to the guide sleeve through the inlay cooperation of the track wedge and the track groove. Under the guidance of the wedge groove cooperation structure between the expansion shoe and the guide sleeve, the expansion shoe can move up and down along the generatrix direction of the outer circumferential conical surface of the guide sleeve.

[0006] The cement crushing device for well cementing is preferably provided with a spring in the annular hydraulic space, and the spring ring is sleeved on the central axis and supported between the upper joint and the piston. Under the elastic force of the spring, the expansion shoe can overcome possible external resistance and fully move downward relative to the guide sleeve to maintain its initial position, thereby improving the reliability of the function of the cement crushing device for well cementing.

[0007] The cement crushing device for well cementing is preferably provided with a hydraulic balance hole on the central axis to connect the dynamic matching surface between the central axis and the piston with the external environment downhole, so as to balance the pressure of the static well fluid on the piston, avoid the static well fluid acting unidirectionally on the piston causing a significant increase in the pressure between the piston and the central axis, thereby causing an increase in the friction force of the piston moving relative to the central axis, and ensure the smoothness and stability of the piston operation.

[0008] The cement crushing device for cementing wells is preferably provided with an anti-drop sleeve in the upper joint, and the upper end of the anti-drop sleeve has a limiting cap, which is cooperatively connected to the upper end of the central shaft to prevent the central shaft and the upper joint from accidentally loosening and falling into the well during operation, thereby improving the safety of production applications.

[0009] The cement crushing device for cementing wells is preferably equipped with 8 expansion shoes hung on the expansion shoe seat, and the expansion shoes are evenly arranged along the circumferential section of the expansion shoe seat.

[0010] The beneficial effect of the utility model is to provide a cementing cement crushing device, which is used in the replacement operation of the working casing of the offshore oil field. It is delivered to the wellbore by a universal drilling tool and driven by the well fluid hydraulic pressure. The radial outer expansion point of the expansion cone is driven to contact and act on the inner wall of the working casing, so that the working casing produces local plastic deformation and then convexly squeezes the cementing cement on the outside of the working casing to produce brittle cracks or form a fragmentation area. The drilling tool is lifted while maintaining the well fluid pressure. During the movement, the expansion cone acts on the working casing to produce a plurality of axially continuous linear plastic deformation areas, further expanding the brittle cracks or fragmentation areas in the cementing cement, thereby achieving the technical effect of separating the working casing from the cementing cement. Then, the separated working casing can be cut, salvaged, and replaced with a new working casing. In production applications, it can replace the traditional cement casing milling and removal method, effectively reduce the intensity of cementing cement crushing operations, shorten the working cycle, and reduce cost consumption. More importantly, there is no need to replace special drilling tools during the operation, and it is not limited by the length of the working casing that needs to be replaced. The overall crushing of the entire area can be achieved in one throw down the well, which has high operating efficiency. At the same time, according to the process requirements, the working casing can be expanded and crushed multiple times in one throw down the well to ensure the reliability of the separation of the working casing and cementing cement, creating favorable conditions for subsequent salvage and replacement of the working casing. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is the basic structure diagram of the cement crushing device for cementing.

[0012] Figure 2 This is the structural diagram of the working status of the cement crushing device.

[0013] Figure 3 for Figure 2 Sectional view of the AA section.

[0014] Among them: 1 is the upper joint, 2 is the center axis, 3 is the hydraulic cylinder, 4 is the guide sleeve, 5 is the piston, 6 is the expansion shoe, 7 is the expansion shoe seat, 8 is the connecting sleeve, 9 is the expansion cone, 10 is the spring, 11 is the cementing cement, 12 is the anti-drop sleeve, 13 is the conical guide head, 14 is the liquid flow hole, 15 is the hydraulic balance hole, and 16 is the inner working casing. DETAILED DESCRIPTION

[0015] Furthermore, the technical solution for which protection is sought in the present utility model is described in detail in conjunction with specific embodiments and their accompanying drawings.

[0016] A cementing cement crushing device, such as Figures 1 to 3 As shown, it is composed of an upper joint 1, a central shaft 2, a hydraulic cylinder 3, a guide sleeve 4, a piston 5, an expansion shoe 6, an expansion shoe seat 7, a connecting sleeve 8, an expansion cone 9, a spring 10 and a locking sleeve 12.

[0017] The upper end of the upper joint 1 is provided with an internal thread, and the lower end is provided with both an internal thread and an external thread. The hydraulic cylinder 3 is sealed and matched with the external thread at the lower end of the upper joint 1, and the central shaft 2 is sealed and matched with the internal thread at the lower end of the upper joint 1. An upper blind hole and a lower blind hole are respectively provided along the axis at the upper and lower ends of the central shaft 2. The upper blind hole is connected to the central water hole of the upper joint 1, and the lower blind hole is connected to the external environment downhole. A conical guide head 13 is provided on the lower end of the central shaft 2, and an anti-drop sleeve 12 is provided in the inner cavity of the upper joint 1. The locking sleeve 12 is connected to the central shaft 2 with a reverse thread at the upper end. The piston 5, the connecting sleeve 8 and the expansion shoe seat 7 are connected in sequence up and down to form a connecting assembly, and the connecting assembly is integrally sleeved on the central shaft 2, wherein the piston 5 is limitedly embedded in the hydraulic cylinder 3 and forms a dynamic sealing match with the hydraulic cylinder 3 and the central shaft 2 respectively, so that the piston 5, the hydraulic cylinder 3 and the upper joint 1 are combined to form a sealed annular hydraulic space, and the annular hydraulic space is connected to the central water eye of the upper joint 1 through the liquid flow hole 14 and the upper blind hole opened on the central shaft 2, and the dynamic matching surface between the piston 5 and the central shaft 2 is also opened on the central shaft 2 The hydraulic balance hole 15 on the well and the lower blind hole are connected to the external environment of the well, and the spring 10 is arranged in the annular hydraulic space, and the spring 10 is supported between the upper joint 1 and the piston 5; the guide sleeve 4 is correspondingly arranged at the lower part of the tile expansion seat 7, and the fixed ring sleeve is on the central axis 2. Eight T-shaped hanging grooves are opened on the tile expansion seat 7, and the T-shaped hanging grooves are evenly distributed on the circumferential section of the tile expansion seat 7. The outer circumference of the guide sleeve 4 is a conical guide surface, and eight dovetail track grooves are opened in the generatrix direction of the conical guide surface. The opening positions of the dovetail track grooves are respectively corresponding to the positions of the tile expansion seat 7 and the T-shaped hanging grooves. The T-shaped hanging grooves opened on the seat 7 correspond to each other; the upper end of the rising shoe 6 has a T-shaped hanging joint, and the structure of the T-shaped hanging joint and the T-shaped hanging groove correspond to each other and are matched and embedded in the T-shaped hanging groove, so that the rising shoe 6 is hung on the rising shoe seat 7, and the inner side surface of the rising shoe 6 is a conical inclined surface and has a dovetail track wedge, and the dovetail track wedge corresponds to the dovetail track groove structure opened on the guide sleeve 4 and is embedded with each other, and the rising cone 9 is fixedly installed on the outer side surface of the rising shoe 6, and the rising cone 9 has a circular spherical cone head, and the circular spherical cone head protrudes from the outer side surface of the rising shoe 6.

[0018] In the basic structure state, such as Figure 1As shown, the connection assembly consisting of the piston 5, the connection sleeve 8 and the expansion shoe seat 7 is pushed by the spring 10 and fully moves downward along the central axis 2. The expansion shoe 6 is fully downward and outward under the guidance of the guide sleeve 4, and the cementing cement crushing device is in a stable structural state. During production and use, the cementing cement crushing device is connected to the drill pipe of the drilling tool by using the internal thread at the upper end of the upper joint 1 and is sent down the well. Since the circumferential outer diameter formed by the expansion cone 9 installed on the expansion shoe 6 is larger than the aperture of the inner working casing 16 of the oil well, during the delivery process, the inner working casing 16 will first push the expansion cone 9, pushing the expansion shoe 6 and the connection assembly to overcome the elastic force of the spring 10 and move upward. Since the expansion shoe 6 is guided by the guide sleeve 4 through the wedge groove matching structure on the conical inclined surface, each expansion shoe 6 simultaneously produces radial centripetal movement during the movement, so that the expansion cone 9 composed of The outer diameter of the circle gradually decreases. When the outer diameter of the circle is reduced to be smaller than the aperture of the inner working casing 16, the cement crushing device can enter the oil well and can continue to be sent down by the drilling tool until the stripping depth of the inner working casing 16. During the sending process, the pushing effect of the spring 10 makes the expansion cone 9 always maintain elastic contact and cooperation with the inner working casing 16; after reaching the stripping depth area, the well fluid pressure is pumped into the drilling tool water hole at the wellhead, and the well fluid pressure is transmitted from the central water hole of the upper joint 1 and the upper blind hole opened on the central axis 2 and through the liquid flow hole 14 to the annular hydraulic space, to the piston 5 applies a downward axial force, which is transmitted to the expansion shoe 6 through the expansion shoe seat 7 of the connecting sleeve 8, and then converted into a radial force of each expansion shoe 6 relative to the inner working casing 16 through the action of the guide sleeve 4, so that the expansion cone 9 is point-contacted and tightened on the inner wall of the inner working casing 16. As the wellbore pressure increases sufficiently, the inner working casing 16 will undergo local plastic deformation, and then convexly squeeze the cementing cement 11 outside the inner working casing 16, so that the rigid cementing cement 11 will produce brittle cracks or form a fragmentation area at the contact portion with the inner working casing 16. Thereafter, under continuous maintenance, While maintaining the wellbore fluid pressure at the wellhead, the drill pipe of the drilling tool is lifted. The dynamic and continuous expansion effect of each expansion cone 9 on the inner working casing 16 during the movement will cause the inner working casing 16 to form a plurality of axially continuous linear plastic deformation areas, thereby causing the cementing cement 11 in the corresponding area to produce continuous brittle cracks or form continuous fragmentation areas, causing the inner working casing 16 to loosen relative to the cementing cement 11 or separate from the cementing cement 11. After that, the inner working casing 16 can be directly salvaged as a whole, which can effectively simplify the operating procedures, significantly improve the operating efficiency, and greatly reduce the production cost compared with the existing technology.

Claims

1. A cement crushing device for cementing, characterized in that: include: An upper joint (1), a central shaft (2), a hydraulic cylinder (3), a guide sleeve (4), a piston (5), an expansion shoe (6), an expansion shoe seat (7), a connecting sleeve (8) and an expansion cone (9); the upper joint (1) is coaxially connected to the central shaft (2) up and down, the upper end of the upper joint (1) is provided with a connecting structure, the lower end of the central shaft (2) has a conical guide head (13), the hydraulic cylinder (3), the piston (5), the connecting sleeve (8), the expansion shoe seat (7) and the guide sleeve (4) are respectively and correspondingly sleeved on the central shaft (2); The hydraulic cylinder (3) is fixedly connected to the upper joint (1) and has a radial spacing with the central axis (2). The piston (5) is limitedly inserted in the hydraulic cylinder (3) and forms a corresponding fit with the central axis (2) and the hydraulic cylinder (3) in the radial direction and can move axially along the central axis (2). The piston (5) is combined with the hydraulic cylinder (3) and the upper joint (1) to form a sealed annular hydraulic space. The annular hydraulic space is connected to the upper joint (1) via a liquid flow hole (14) provided on the central axis (2). ) are connected to the central water hole of the hydraulic cylinder (3); the shoe-increasing seat (7) and the guide sleeve (4) are arranged in sequence at the lower part of the hydraulic cylinder (3) in correspondence with each other, wherein the shoe-increasing seat (7) is connected to the piston (5) through the connecting sleeve (8), and the guide sleeve (4) is fixedly connected to the central axis (2); the shoe-increasing seat (7) is provided with a T-shaped hanging groove, and the T-shaped hanging groove is evenly distributed on the circumferential section of the shoe-increasing seat (7); and a conical guiding surface is provided on the outer circumference of the guide sleeve (4); the shoe-increasing seat (6) is a strip-shaped plate body, The upper end is provided with a T-shaped hanging joint, and the T-shaped hanging joint can be matched and embedded in the T-shaped hanging groove so that the expansion shoe (6) is correspondingly hung on the expansion shoe seat (7) and keeps the expansion shoe (6) radially movable relative to the expansion shoe seat (7). The inner side surface of the expansion shoe (6) is a conical inclined surface, and the conical inclined surface corresponds to the conical guide surface structure on the outer circumference of the guide sleeve (4) and is arranged in cooperation with each other. The expansion cone (9) is fixedly installed on the outer side surface of the expansion shoe (6), and the cone head of the expansion cone (9) protrudes from the outer side surface of the expansion shoe (6).

2. A cement crushing device for cementing as claimed in claim 1, characterized in that: A vertically arranged track wedge is provided on the inner side surface of the expansion shoe (6), and a track groove having a structure corresponding to the track wedge is provided on the outer circumferential surface of the guide sleeve (4). The expansion shoe (6) is connected to the guide sleeve (4) through the fit between the track wedge and the track groove.

3. A cement crushing device for cementing as claimed in claim 2, characterized in that: A spring (10) is arranged in the annular hydraulic space. The spring (10) is sleeved on the central shaft (2) and supported between the upper joint (1) and the piston (5).

4. A cement crushing device for cementing as claimed in claim 3, characterized in that: A hydraulic balance hole (15) is provided on the central shaft (2) to enable the dynamic matching surface between the piston (5) and the central shaft (2) to communicate with the external environment downhole.

5. A cement crushing device according to any one of claims 1 to 4, characterized in that: An anti-drop sleeve (12) is provided in the upper joint (1), and the upper end of the anti-drop sleeve (12) is provided with a limiting cap which is cooperatively connected to the upper end of the central shaft (2).

6. A cement crushing device for cementing as claimed in claim 5, characterized in that: Eight pieces of the expansion tiles (6) are hung on the expansion tile seat (7), and the expansion tiles (6) are evenly arranged along the circumferential section of the expansion tile seat (7).

Images