Titanium alloy oil casing wellhead screwing-on auxiliary mechanism and using method

Abstract

The invention discloses a titanium alloy oil casing wellhead screwing-on auxiliary mechanism and a using method. The mechanism comprises a hooking piece. One end of the lifting piece is connected with the hooking piece, and the other end of the lifting piece is fixedly connected with an elastic piece; the clamping device is connected with the elastic piece; and the lifting piece is used for driving the clamping device to clamp or loosen the tubular column. The wellhead screwing-on auxiliary mechanism is convenient to operate on site, high in operation efficiency and capable of completely overcoming the influence of factors such as the gravity of an oil well pipe, wellhead misalignment, swing of a hook and wind power during screwing-on operation of threads of an oil well pipe column, the position of the oil well pipe can be easily adjusted in a small range at the wellhead, adjustment and screwing-on work can be completed by one operator, and the operation efficiency is greatly improved. And the buckling success rate is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of wellhead equipment for oil and gas development, and particularly relates to a make-up assisting mechanism for titanium alloy oil and casing pipes at the wellhead and a using method thereof. Background Art

[0002] With the further deepening of oil and gas development, many oil and gas fields in the western and southwestern regions of China have characteristics such as high temperature (greater than 140 °C), high pressure (greater than 100 MPa), deep well depth (greater than 5000 m), and high corrosion media (CO2, H2S, Cl-), which impose more stringent requirements on the performance of oil well pipes. At present, due to excellent properties such as high strength, low density, excellent corrosion resistance, low elastic modulus, and resistance to seawater erosion, titanium alloy materials have been used to manufacture oil well pipes such as tubing, casing, and drill pipes, and have very excellent performance. The ultra-deep high-temperature and high-pressure gas well oil well pipe is a kind of oil well pipe specifically applied to the above-mentioned oil and gas fields. The main connection method of this oil well pipe is to use special threaded joints for connection, and the quality of on-site threading directly affects the structural integrity and sealing integrity of the entire pipe string during service operation.

[0003] Due to the complex on-site operation environment, during the make-up process, factors such as the self-weight of the oil well pipe, misalignment of the wellhead, swing of the crown block, and wind force will all affect the accuracy of the male thread of the oil well pipe entering the thread groove of the coupling, resulting in the problem of unable to accurately and efficiently align the threads. Especially for titanium alloy oil well pipes, due to the characteristics of the material itself, the thread surface is easily damaged and not wear-resistant. If problems such as inaccurate thread alignment, wrong threading, insufficient or excessive make-up torque occur during on-site operation, it will cause serious damage to the threads, further affecting the connection strength and sealing effect of the threaded joints. At the same time, due to the cask effect of special thread sealing, leakage and other failures are likely to occur first at the weak points, posing a great threat to the safety of the entire oil well pipe string. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems in the prior art, and provides a make-up assisting mechanism for titanium alloy oil and casing pipes at the wellhead and a using method thereof.

[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions to implement:

[0006] According to the first aspect of the present invention, a make-up assisting mechanism for titanium alloy oil and casing pipes at the wellhead is provided, including:

[0007] A hook hanging member;

[0008] A lifting member, one end of which is connected to the hook hanging member, and the other end is fixedly connected with an elastic member;

[0009] A clamping device, connected to the elastic member;

[0010] The lifting member is used to drive the clamping device to clamp or release the pipe column.

[0011] Further, the clamping device comprises a slip shell, the slip shell is connected to the elastic member, and the inner side of the slip shell is connected to a clamping assembly via a movable member;

[0012] Wherein, when the lifting member lowers the clamping device through the elastic member, the slip housing is separated from the clamping assembly so that the clamping assembly releases the pipe column;

[0013] In addition, when the lifting member pulls up the clamping device through the elastic member, the slip shell overlaps with the clamping assembly so that the clamping assembly clamps the pipe column.

[0014] Furthermore, the clamping assembly includes a slip decomposition tooth body and a friction clamping tooth, the slip decomposition tooth body is provided in plurality, the plurality of slip decomposition tooth bodies are connected by a tooth body connector, and a reset piece is provided in the tooth body connector;

[0015] The plurality of slip decomposition teeth are all movably connected to the slip shell through movable parts, and at least one friction clamping tooth is arranged on the inner side of the plurality of slip decomposition teeth;

[0016] Wherein, when the slip shell is separated from the plurality of slip decomposition teeth, the plurality of slip decomposition teeth are spread out along the circumferential direction through the resetting member to loosen the pipe column;

[0017] In addition, when the slip shell and the plurality of slip decomposing teeth overlap, the plurality of slip decomposing teeth are tightly clamped along the circumferential direction so that the friction clamping teeth clamp the pipe column.

[0018] Furthermore, a plurality of the slip decomposition teeth form a cone structure, the inner side of the slip shell is provided with a cone surface adapted to the cone structure, and the movable part is circumferentially arranged on the cone surface.

[0019] Furthermore, the movable part includes a ball.

[0020] Furthermore, the movable part also includes a bearing.

[0021] Furthermore, the lifting member is a cylinder; or, the lifting member is a hydraulic cylinder.

[0022] Furthermore, the elastic member is a mechanical spring force storage structure; or, the elastic member is a hydraulic spring force storage structure.

[0023] Furthermore, a protective member and a monitoring member are provided on the elastic member, and the protective member is a sliding sleeve telescopic structure, which is installed on the outside of the elastic member;

[0024] The monitoring member is used to monitor the working state, load and elongation of the elastic member.

[0025] According to a second aspect of the present invention, there is provided a method for using an auxiliary mechanism, which is carried out by using the auxiliary mechanism as described above, and includes:

[0026] Install the components on the drilling equipment;

[0027] Pass the oil well pipe through the components on the drilling equipment;

[0028] Perform operations of threading, guiding and screwing on the threads of the oil well pipe passing through the components.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The on-site operation of the wellhead screwing auxiliary mechanism is convenient, the operation efficiency is high. When screwing the threads of the oil well pipe string, it can completely overcome the influence of factors such as the self-gravity of the oil well pipe, the misalignment of the wellhead, the swing of the hook and the wind force. Moreover, the position of the oil well pipe at the wellhead can be easily adjusted within a small range, and one operator can complete the adjustment and screwing work, and the threading success rate is high.

[0031] 2. The auxiliary mechanism is simple to operate, has good stability, strong adaptability during the process of screwing the oil well pipe at the wellhead, and will not add additional complex processes and equipment to the on-site operation of lowering the oil well pipe.

[0032] 3. The auxiliary mechanism can not only meet the use requirements of different sizes of pipes on site, but also be used for screwing operations of different types of oil well pipes such as oil pipes, casing pipes, drill pipes and tools.

[0033] 4. The auxiliary mechanism is safe and reliable during use, can significantly reduce the impact on the on-site environment, can be applied to a variety of harsh working conditions and construction conditions, and a monitoring component is designed on the auxiliary mechanism, which can monitor and analyze the entire device and operation in real time, enabling the on-site and backstage to timely understand the threading situation, and has a high degree of intelligence. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1 It is a schematic diagram of the overall titanium alloy oil casing wellhead screwing auxiliary mechanism provided by the present invention;

[0036] Figure 2Schematic assembly diagram of the clamping device in the auxiliary mechanism for screwing on the titanium alloy oil casing wellhead provided by the present invention;

[0037] Figure 3 Exploded view of the clamping device in the auxiliary mechanism for screwing on the titanium alloy oil casing wellhead provided by the present invention;

[0038] Figure 4 Schematic installation diagram of the tooth body connecting piece in the auxiliary mechanism for screwing on the titanium alloy oil casing wellhead provided by the present invention;

[0039] Figure 5 Schematic flow diagram of the usage method of the auxiliary mechanism provided by the present invention;

[0040] Wherein: 1, coupling; 2, hook; 3, elevating bowl; 4, cylinder block; 5, load-bearing tension spring; 6, safety slips; 7, pipe string; 8, tension spring protection cover; 9, hook hoisting mechanism; 10, slips housing; 11, disassembled tooth body of slips; 12, friction clamping teeth; 13, movable part; 14, tooth body connecting piece. Detailed implementation manners

[0041] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. The components of the embodiments of the present invention usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0042] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0043] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0044] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed during use. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it should not be construed as a limitation to the present invention. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0045] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0046] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "connected" are used, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] The following further describes the present invention in detail with reference to the drawings:

[0048] The embodiments of the present invention provide a make-up auxiliary mechanism for titanium alloy oil casing wells and a usage method.

[0049] As Figure 1 shown, according to the first aspect of the present invention, a make-up auxiliary mechanism for titanium alloy oil casing wells is provided, including: a hook hanging member; a lifting member, one end of which is connected to the hook hanging member, and the other end is fixedly connected with an elastic member; a clamping device connected to the elastic member; the lifting member is used to drive the clamping device to clamp or release the pipe string 7. Further, the clamping device is a safety slip 6, and the safety slip 6 includes a slip housing 10, the slip housing 10 is connected to the elastic member, and a clamping assembly is connected to the inner side of the slip housing 10 through a movable member 13; wherein, when the lifting member lowers the clamping device through the elastic member, the slip housing 10 is separated from the clamping assembly to enable the clamping assembly to release the pipe string 7; in addition, when the lifting member pulls up the clamping device through the elastic member, the slip housing 10 coincides with the clamping assembly to enable the clamping assembly to clamp the pipe string 7.

[0050] In this embodiment, as Figure 3 and Figure 4As shown, the clamping assembly includes a slip decomposing tooth body 11 and a friction clamping tooth 12, and a plurality of slip decomposing tooth bodies 11 are provided. The plurality of slip decomposing tooth bodies 11 are connected by a tooth body connecting piece 14, and a reset piece is provided in the tooth body connecting piece 14; the plurality of slip decomposing tooth bodies 11 are movably connected to the slip housing 10 through a movable piece 13, and at least one friction clamping tooth 12 is provided on the inner side of the plurality of slip decomposing tooth bodies 11; the friction clamping tooth 12 is used to tighten the pipe column 7; specifically, when the lifting piece is pulled up to separate the slip housing 10 from the plurality of slip decomposing tooth bodies 11, the plurality of slip decomposing tooth bodies 11 are spread out along the circumferential direction through the reset piece to release the pipe column 7; in addition, when the slip housing 10 and the plurality of slip decomposing tooth bodies 11 overlap, the plurality of slip decomposing tooth bodies 11 are clamped in the circumferential direction so that the friction clamping tooth 12 clamps the pipe column 7.

[0051] In this embodiment, if Figure 3 and Figure 4 As shown, a plurality of slip decomposition teeth 11 form a cone structure, a cone surface adapted to the cone structure is provided on the inner side of the slip housing 10, and a movable part 13 is arranged circumferentially on the cone surface. Specifically, in this embodiment, the movable part 13 is a ball in one embodiment; in another embodiment, the movable part 13 is a bearing, which can be selected according to the weight and wall thickness of the titanium alloy oil pipe during operation.

[0052] In this implementation, in one embodiment, the lifting member is a cylinder body 4, and the cylinder body 4 is a pneumatic cylinder; in another embodiment, the cylinder body 4 is a hydraulic cylinder.

[0053] In this embodiment, the reset element is a reset spring.

[0054] In this embodiment, in one implementation, the elastic member is a mechanical spring force storage structure; in another implementation, the elastic member is a hydraulic spring force storage structure.

[0055] In this embodiment, a protective member and a monitoring member are provided on the elastic member. The protective member is a sliding sleeve telescopic structure installed outside the elastic member. The monitoring member is used to monitor the working state, load and elongation of the elastic member. Specifically, the elastic member is a load-bearing tension spring 5, and the protective member is a tension spring protective cover 8, which is used to protect the load-bearing tension spring 5.

[0056] In this embodiment, the hooking member is a hook 2 made of steel material, which is mainly used to connect the entire auxiliary mechanism to the hook hoisting mechanism 9 on the drilling equipment. The hook 2 is connected to the following cylinder block 4. The hook 2 can be made into various shapes and lengths according to different requirements, which is convenient for the installation and use of the auxiliary mechanism for making up the connection at the wellhead. The hook 2 and the load-bearing spring 5 are connected by the cylinder block 4. The cylinder block 4 adopts a double-acting air cylinder or a hydraulic cylinder, and a pneumatic or hydraulic transmission mechanism is used to drive the cylinder to extend and shorten along the axis of the cylinder to realize the functions of lifting and lowering the auxiliary mechanism, and further realize the operation of clamping and releasing the pipe string 7 through lifting and lowering control. The load-bearing spring 5 adopts a mechanical spring energy storage or a hydraulic energy storage structure. By setting a load force with a relatively high safety factor, a spring protection cover 8 is installed outside the load-bearing spring 5 to physically protect the entire load-bearing spring 5 when the spring extends or contracts, preventing the load-bearing spring 5 from accidentally breaking or being damaged by the external environment. The main function of the entire load-bearing spring 5 is that when the cylinder lifts the oil well pipe to a suitable position, the self-weight of the pipe string 7 is balanced with the tensile force of the load-bearing spring 5, so as to achieve the purpose that the titanium alloy oil well pipe can easily float up and down in a short distance near the wellhead tongs. Connected below the load-bearing spring 5 is the safety slip 6. The safety slip 6 is a key component for clamping and releasing the titanium alloy oil well pipe string 7. The safety slip 6 is composed of a slip housing 10, slip split teeth 11 and a movable member 13. As Figure 2 shown, on the inner side of the slip split teeth 11, there are friction clamping teeth 12 for clamping the oil well pipe string 7 to prevent it from sliding. The slip split teeth 11 are connected by tooth connectors 14, which can realize loosening and clamping in the circumferential direction. The inner wall of the slip housing 10 and the outer wall of the slip split teeth 11 are both conical. On the inner wall of the slip housing 10, there is a movable member 13, which is composed of a series of balls arranged along the conical surface to realize the sliding friction between the slip housing 10 and the slip split teeth 11. As Figure 3 shown, when the cylinder block 4 is lowered, due to the friction clamping between the friction clamping teeth 12 and the pipe string 7, the slip split teeth 11 are kept in place. Since there is no restriction between the slip housing 10 and the slip split teeth 11, and the slip housing 10 drops under the action of gravity, the slip split teeth 11 and the slip housing 10 separate along the conical surface, and the slip split teeth 11 loosen in the circumferential direction, thus loosening the pipe string 7. As Figure 4 shown. When the cylinder block 4 is pulled up, the slip housing 10 rises along the conical surface, causing the slip split teeth 11 to clamp in the circumferential direction, so as to promote the friction clamping teeth 12 on the inner side of the slip split teeth 11 to clamp the pipe string 7, realizing the operation of clamping the pipe string 7. As Figure 1 and Figure 2As shown in the figure, considering the safety of on-site construction and the operating distance, the entire auxiliary mechanism for screwing up the wellhead of the oil well pipe places the cylinder block 4 on top of the load-bearing spring 5 and the safety slip 6 at the bottommost end, so that the entire compensation mechanism no longer relies on the coupling 1 of the wellhead, having greater flexibility and operating space. The hook 2 at the upper end of the auxiliary mechanism for screwing up the wellhead is directly connected to the hook hoisting mechanism 9 of the drilling equipment, without affecting the normal operation of screwing up and lowering the oil well pipe. It realizes the integrated operation of screwing-up assistance and lowering the pipe string 7, simplifies the auxiliary mechanism for screwing up the wellhead of the oil well pipe, and at the same time ensures the safety, reliability and stability of this special material, the titanium alloy oil well pipe, during the screwing-up operation, and the operation is more flexible. At the same time, according to the difficulty and requirements of on-site operations, each auxiliary mechanism for screwing up the wellhead of the titanium alloy oil well pipe can also be composed of 3 groups or even more auxiliary mechanisms parallel to the pipe string 7. The safety slip 6 can be composed of a slip housing 10 and multiple slip split teeth 11, and is specifically set according to the size of the titanium alloy oil well pipe. The friction clamping teeth 12 on the inner side of the slip split teeth 11 can be made of materials with high friction coefficients such as copper alloy, wear-resistant material, metal or non-metal, and at the same time cause less damage to the titanium alloy, so as to ensure that the titanium alloy oil well pipe is not damaged during the clamping process. The moving part 13 can be composed of materials and structures with low frictional resistance such as balls, bearings, sliding blocks, etc. of various materials, mainly to reduce the frictional resistance between the slip housing 10 and the slip split teeth 11. A reset part is provided in the tooth connecting part 14 of the slip split teeth 11, and the reset part is a reset spring, which ensures that the slip split teeth 11 are separated circumferentially after the slip split teeth 11 and the slip housing 10 are separated. The spring protection cover 8 outside the load-bearing spring 5 can be made of materials with certain protection capabilities such as metal and non-metal. The spring protection cover 8 can be telescopic, and the installation of the monitoring part can conduct real-time monitoring and evaluation of the working state, load, elongation, etc. of the load-bearing spring 5.

[0057] The following takes titanium alloy oil pipes with different wall thicknesses as examples for illustration.

[0058] Example 1:

[0059] When the 3-1 / 2in titanium alloy oil pipe (7.34mm wall thickness) needs to be buckled on and the pipe column 7 is operated on site, the weight of a single oil pipe can be calculated to be 73kg according to the design. Therefore, a load-bearing tension spring 5 with a mechanical spring force storage structure is selected. The maximum working load of a single load-bearing tension spring 5 is 120kg, and there are two load-bearing tension springs 5 in total. The cylinder body 4 uses a compensating cylinder with a double-acting cylinder design, and the maximum working tensile lowering load of the compensating cylinder is 120kg; a safety slip 6 with a load force of about 2500kg is selected, and the friction clamping teeth 12 on the inner side of the safety slip 6 can be made of a polymer material with a high friction coefficient, which causes less damage to the titanium alloy to ensure that the titanium alloy oil well pipe is not damaged during the clamping process; the tension spring protection cover 8 outside the load-bearing tension spring 5 is made of a high-strength metal material, and the tension spring protection cover 8 is designed with a sliding sleeve telescopic structure. A monitoring component is designed on the load-bearing tension spring 5 to monitor and upload the working state, load, elongation, etc. of the load-bearing tension spring 5 in real time. A movable part 13 is arranged on the inner wall of the safety slip shell 10. The movable part 13 is composed of steel balls in series and fixed on the inner wall of the slip shell 10, which can reduce the friction resistance between the slip shell 10 and the slip decomposition tooth body 11.

[0060] Through calculation and verification, the load of the oil well pipe string 7 + lower safety slip 6 is 75kg, the calculated safety factor of the load-bearing tension spring 5 is 3.2, the calculated safety factor of the compensation cylinder is 3, and the safety factor of the safety slip 6 is greater than 15. A steel hook 2 is selected, and the load of a single hook 2 exceeds 300kg. After arriving at the site, the hook 2, the compensation cylinder, the load-bearing tension spring 5 and the safety slip 6 are assembled in sequence from top to bottom to form a set of compensation auxiliary mechanisms. Two sets of compensation auxiliary mechanisms are prepared, and the two sets of compensation auxiliary mechanisms are connected with the hook 2 on the big hook lifting mechanism 9 of the drilling equipment (so that the cylinder body 4 is in an extended state). The lower ends of the two sets of compensation auxiliary mechanisms are connected with a safety slip 6; the titanium alloy oil pipe is lifted out from the platform, and the oil pipe passes through the middle of the slip decomposition tooth 11 in the safety slip 6. The lifting card 3 clamps the coupling 1 of the oil pipe and lifts it, so that the oil pipe string 7 passes through the wellhead tie-up auxiliary mechanism and is suspended above the wellhead tie-up auxiliary mechanism; the compensation cylinder contracts and lifts the safety slip 6, so that the slip decomposition teeth 11 on the safety slip 6 slide along the conical surface to clamp the oil well pipe string 7, and lift the oil well pipe string 7; at this time, the oil well pipe string 7 is in a zero gravity state under the action of the load-bearing tension spring 5 of the oil well pipe wellhead tie-up auxiliary mechanism, and the height of the lifting card 3 is adjusted so that the thread of the oil well pipe string 7 and the wellhead tie-up auxiliary mechanism are in a suitable tie-up position, so that the oil pipe thread can be easily tied, led, and tied; after the tie-up, the compensation cylinder extends out, and the safety slip 6 on the wellhead tie-up auxiliary mechanism of the oil well pipe is lowered, and the slip decomposition teeth 11 on the safety slip 6 slide along the conical surface to loosen the oil well pipe string 7, and the oil well pipe string 7 that has been tied up is lowered.

[0061] Embodiment 2:

[0062] When the 7-6 / 8in titanium alloy casing (15.11mm wall thickness) needs to be buckled up and down on site, the weight of a single casing can be calculated to be 340kg according to the design. Therefore, a load-bearing tension spring 5 with a hydraulic spring force storage structure is selected, and the maximum working load of a single load-bearing tension spring 5 is 500kg, and there are two load-bearing tension springs 5 in total. The cylinder body 4 uses a compensating cylinder designed with a double-acting hydraulic cylinder, and the maximum working tensile lowering load of the compensating cylinder is 300kg; a safety slip 6 with a load force of about 2500kg is selected, and the friction clamping teeth 12 on the inner side of the safety slip 6 can be made of a high friction coefficient material of copper + WC, which has little damage to the titanium alloy to ensure that the titanium alloy oil well pipe column 7 is not damaged during the clamping process; the tension spring protection cover 8 outside the load-bearing tension spring 5 is made of a high-strength metal material, and the tension spring protection cover 8 is a sliding sleeve telescopic structure. A monitoring component is set on the load-bearing tension spring 5 to monitor and upload the working state, load, elongation, etc. of the load-bearing tension spring 5 in real time. The inner wall of the safety slip housing 6 is provided with a movable part 13, which is composed of high-strength bearings connected in series and fixed on the inner wall of the slip housing 10, and can reduce the friction resistance between the slip housing 10 and the slip decomposition tooth 11. Through calculation and verification, the load of the titanium alloy oil well pipe string 7 + the lower safety slip 6 is 345kg, the calculated safety factor of the load-bearing tension spring 5 is 2.9, the calculated safety factor of the compensation cylinder is 1.7, and the safety factor of the safety slip 6 is greater than 7. The hook 2 made of alloy steel is selected, and the load of a single hook 2 exceeds 500kg. After arriving at the site, the hook 2, the compensation cylinder, the load-bearing tension spring 5 and the safety slip 6 are assembled in order from top to bottom to form a set of compensation auxiliary mechanisms. Three sets of compensation auxiliary mechanisms are prepared. The three sets of compensation auxiliary mechanisms are connected with the hook 2 on the large hook lifting mechanism 9 of the drilling equipment (so that the cylinder body 4 is in an extended state), and the lower ends of the three sets of compensation auxiliary mechanisms are connected with a safety slip 6; the oil well pipe string 7 is lifted out from the platform, and the pipe string 7 is passed through the middle of the slip decomposition teeth 11 in the safety slip 6; the lifting card 3 clamps the coupling 1 of the pipe string 7 and lifts it, so that the oil well pipe string 7 passes through the wellhead buckle auxiliary mechanism and is suspended above the wellhead coupling 1; the compensation The compensation cylinder contracts and lifts the safety slip 6, so that the slip decomposing teeth 11 on the safety slip 6 slide along the conical surface to clamp the oil well pipe string 7 and lift it; at this time, the oil well pipe string 7 is in a zero gravity state under the action of the load-bearing tension spring 5 of the oil well pipe wellhead tie-up auxiliary mechanism, and the height of the elevator 3 is adjusted so that the thread of the oil well pipe string 7 and the wellhead coupling 1 are in a suitable tie-up position, so that the thread of the oil well pipe string 7 can be easily tied, led and tied; after tie-up, the compensation cylinder extends out, and the safety slip 6 on the oil well pipe wellhead tie-up auxiliary mechanism is lowered, and the slip decomposing teeth 11 on the safety slip 6 slide along the conical surface to loosen the oil well pipe string 7, and the oil well pipe string 7 that has been tied up is lowered.

[0063] According to a second aspect of the present invention, a method for using an auxiliary mechanism is provided. The method is carried out by using the auxiliary mechanism as described above, and includes:

[0064] S101. Install the components on the drilling equipment; select appropriate models of compensation cylinders, load-bearing springs 5, and safety slips 6 according to the specifications of the oil well pipe string 7 to be made up and the requirements for special thread operations; assemble the hook 2, compensation cylinder, load-bearing spring 5, and safety slip 6 in sequence from top to bottom to form a set of compensation auxiliary mechanisms, and prepare two sets of compensation auxiliary mechanisms for operation.

[0065] S102. Pass the oil well pipe through the components on the drilling equipment; connect two sets of compensation auxiliary mechanisms with the hook 2 on the hook hoisting mechanism 9 on the drilling equipment (keep the cylinder body 4 in the extended state), and connect the two sets of compensation auxiliary mechanisms at the lowermost end with a safety slip 6; lift out the oil well pipe string 7 from the platform, pass the oil well pipe string 7 through the split teeth 11 of the slip in the safety slip 6, and the elevator 3 holds the oil well pipe string 7 and lifts it, so that the oil well pipe string 7 passing through the wellhead make-up auxiliary mechanism is suspended above the wellhead collar 1.

[0066] S103. Perform operations of threading, guiding the thread, and making up the thread for the oil well pipe thread passing through the components. The compensation cylinder contracts to lift the safety slip 6, so that the split teeth 11 of the slip on the safety slip 6 slide along the conical surface to clamp the oil well pipe string 7 and lift the oil well pipe string 7; at this time, the oil well pipe string 7 is in a zero-gravity state under the action of the load-bearing spring 5 in the wellhead make-up auxiliary mechanism of the oil well pipe. Adjust the height of the elevator 3 so that the thread of the oil well pipe string 7 is in a suitable position for making up the thread with the wellhead collar 1, and then the thread of the oil well pipe string 7 can be easily threaded, guided, and made up; after making up the thread, the compensation cylinder extends, and the safety slip 6 on the wellhead make-up auxiliary mechanism of the oil well pipe is lowered, and the split teeth 11 of the slip on the safety slip 6 slide along the conical surface to release the oil well pipe string 7.

[0067] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An auxiliary mechanism for screwing on the wellhead of titanium alloy oil casing pipes, characterized in that, include: Hooks and hanging parts; A lifting member, one end of which is connected to the hook member, and the other end of which is fixedly connected to an elastic member; A clamping device connected to the elastic member; The lifting member is used to drive the clamping device to clamp or release the pipe column.

2. The auxiliary mechanism according to claim 1, characterized in that, The clamping device comprises a slip shell, the slip shell is connected to an elastic member, and the inner side of the slip shell is connected to a clamping assembly via a movable member; Wherein, when the lifting member lowers the clamping device through the elastic member, the slip housing is separated from the clamping assembly so that the clamping assembly releases the pipe column; In addition, when the lifting member pulls up the clamping device through the elastic member, the slip shell overlaps with the clamping assembly so that the clamping assembly clamps the pipe column.

3. The auxiliary mechanism according to claim 2, characterized in that, The clamping assembly comprises a slip decomposition tooth body and a friction clamping tooth, wherein the slip decomposition tooth body is provided in plurality, and the plurality of slip decomposition tooth bodies are connected by a tooth body connector, and a reset piece is provided in the tooth body connector; The plurality of slip decomposition teeth are all movably connected to the slip shell through movable parts, and at least one friction clamping tooth is arranged on the inner side of the plurality of slip decomposition teeth; Wherein, when the slip shell is separated from the plurality of slip decomposition teeth, the plurality of slip decomposition teeth are spread out along the circumferential direction through the resetting member to loosen the pipe column; In addition, when the slip shell and the plurality of slip decomposing teeth overlap, the plurality of slip decomposing teeth are tightly clamped along the circumferential direction so that the friction clamping teeth clamp the pipe column.

4. The auxiliary mechanism according to claim 3, characterized in that, A cone structure is formed between the plurality of slip decomposition teeth, a cone surface adapted to the cone structure is provided on the inner side of the slip shell, and the movable part is circumferentially arranged on the cone surface.

5. The auxiliary mechanism according to any one of claims 2-4, characterized in that, The movable part includes a ball.

6. The auxiliary mechanism according to any one of claims 2-4, characterized in that, The movable part further comprises a bearing.

7. The auxiliary mechanism according to claim 1, characterized in that, The lifting member is a cylinder; or, the lifting member is a hydraulic cylinder.

8. The auxiliary mechanism according to claim 1, characterized in that, The elastic member is a mechanical spring force storage structure; or, the elastic member is a hydraulic spring force storage structure.

9. The auxiliary mechanism according to claim 1 or 8, characterized in that, The elastic member is provided with a protective member and a monitoring member, wherein the protective member is a sliding sleeve telescopic structure and is installed outside the elastic member; The monitoring member is used to monitor the working state, load and elongation of the elastic member.

10. A method for using an auxiliary mechanism, characterized in that, The method is carried out using the auxiliary mechanism according to any one of claims 1 to 9, comprising: Install components on drilling equipment; Passing the oil well pipe through the components on the drilling equipment; The oil well pipe threads passing through the components are subjected to the operations of buckling, leading buckling and making up.

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