In-line pipe cutter for liquid supply pipe

Abstract

The application relates to the technical field of pipe cutting devices, and provides a pipe-in pipe cutting device for a liquid supply pipe, which comprises a central shaft, gravity dismounting hammers are arranged at the two ends of the central shaft, a lower sliding sleeve is arranged at the lower end of the central shaft, an upper sliding sleeve is rotationally connected to the upper end surface of the lower sliding sleeve, upper cutter holders and lower cutter holders are slidably connected to the inner walls of the upper sliding sleeve and the lower sliding sleeve, the central shaft penetrates the upper cutter holders and the lower cutter holders, the upper cutter holders and the lower cutter holders are rotationally connected, a plurality of left-hand cutters are hinged to the side surface of the upper cutter holder, a plurality of right-hand cutters are hinged to the side surface of the lower cutter holder, cutter holes are arranged in the side surface of the upper sliding sleeve, cutter holes are arranged in the side surface of the lower sliding sleeve, a lock piece is hinged to the lower end of the lower cutter holder, a lock hole is arranged in the side surface of the lower sliding sleeve, a tower spring is arranged between the lock piece and the lower cutter holder, and the tower spring is used for pushing the lock piece into the lock hole. The upper and lower cutters are cut from two opposite directions respectively, the liquid supply pipe is cut off, and the liquid supply pipe recovery operation is realized.

Description

Technical Field

[0001] This invention relates to the field of pipe cutting technology, specifically to a pipe cutting tool for a liquid supply pipe. Background Technology

[0002] In freezing construction, the supply pipe, as the core component of the freezer, undertakes the crucial task of delivering cryogenic brine to the bottom of the freezing pipe. During the freezing operation, cryogenic brine circulates inside the supply pipe, forming a ring-shaped reflux channel with the freezing pipe wall, achieving continuous heat exchange with the formation.

[0003] However, practical experience in freezing engineering shows that the retrieval of the supply pipe has long faced significant technical challenges. On the one hand, during the service life of the freezing pipe, it is often subjected to complex loads such as ground creep, alternating frost heave and thaw settlement, and vibration and impact from blasting operations. This often causes localized collapse and deformation of the freezing pipe, resulting in the supply pipe inside becoming jammed and unable to be lifted upwards. On the other hand, the counterweight installed at the bottom of the freezing pipe, due to micro-deformation of the pipe wall or thickening of scale during long-term operation, rubs against and obstructs the inner wall of the freezing pipe, similarly hindering the normal extraction of the supply pipe. These jamming phenomena are particularly prominent in complex geological conditions such as water-rich soft rock and alluvial deposits.

[0004] Currently, there are two main conventional methods for dealing with the problem of supply pipes getting stuck and unable to be pulled out normally: one is to increase the pulling force to forcibly pull them out, but this method is very likely to cause the supply pipe to break and the freezing pipe to be damaged; the other is to abandon the recovery and leave the supply pipe and the freezing pipe together in the formation. This method not only causes a lot of material waste and increases construction costs, but the supply pipe left in the freezing pipe will also seriously hinder the subsequent cement mortar filling construction of the freezing pipe, affecting the filling density and sealing quality, and creating hidden dangers for the long-term safe operation of underground projects.

[0005] Therefore, there is a need for a pipe cutter for the supply pipe, which can cut it off from the bottom to separate the counterweight and eliminate scraping, or cut it off from above the deformed part of the collapsed pipe to avoid the stuck section, thereby maximizing the recovery of the supply pipe while creating favorable conditions for subsequent freezing pipe filling construction. Summary of the Invention

[0006] The purpose of this invention is to provide an in-pipe cutter for a liquid supply pipe, which aims to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a pipe cutter for a liquid supply pipe, comprising a central shaft, with a gravity-driven ejector hammer and a sliding sleeve respectively disposed at both ends of the central shaft. An upper sliding sleeve is rotatably connected to the upper end face of the sliding sleeve. An upper tool holder and a lower tool holder are slidably connected to the inner walls of the upper and lower sliding sleeves, respectively. Positioning grooves are provided on the sides of both the upper and lower tool holders. Positioning protrusions are connected to the inner walls of both the upper and lower sliding sleeves, and the positioning protrusions are slidably connected to the corresponding positioning grooves. The central shaft passes through the upper... The tool holder and lower tool holder have a lower locking nut connected to the lower end of the central shaft. The lower locking nut is rotatably connected to the lower tool holder. The upper tool holder and lower tool holder are rotatably connected. Several left-handed tools are hinged to the side of the upper tool holder, and several right-handed tools are hinged to the side of the lower tool holder. The side of the upper sliding sleeve has an upper tool hole, and the side of the lower sliding sleeve has a lower tool hole. A locking element is hinged to the lower end of the lower tool holder. The side of the lower sliding sleeve also has a locking hole. A tower spring is installed between the locking element and the lower tool holder. The tower spring is used to push the locking element into the locking hole.

[0008] As a further embodiment of the present invention, both the upper and lower tool holders are provided with a central hole, and the upper and lower tool holders are sleeved on the outside of the central shaft. Two left-handed tools are installed on the upper tool holder, and three right-handed tools are installed on the lower tool holder.

[0009] As a further embodiment of the present invention, both the left-hand and right-hand cutting tools have a 7.5mm cutting edge at the head, the tools are flat-edged with rounded tips, and the cutting edge is designed with a 3-degree elevation angle.

[0010] As a further embodiment of the present invention, the gravity-driven hammer includes a hammer sleeve and a first counterweight. The top of the hammer sleeve is hemispherical. The first counterweight is fixedly installed on the inner wall of the hammer sleeve by fastening bolts. A hollow groove is provided inside the first counterweight. The upper end of the central shaft is connected to a locking nut, which can move in the hollow groove.

[0011] As a further embodiment of the present invention, a second counterweight is connected to the top end of the inner wall of the upper sliding sleeve, and a third counterweight is connected to the lower end of the inner wall of the lower sliding sleeve. Both the second and third counterweights are fixedly installed by fastening bolts.

[0012] As a further embodiment of the present invention, the upper end face of the third counterweight is provided with a groove, the bottom surface of the third counterweight is fixedly connected with a lifting lug, and the top surface of the gravity-driven knife-removing hammer is fixedly connected with a lifting lug.

[0013] As a further embodiment of the present invention, the upper end face of the lower lock nut is rotatably connected to the lower end face of the lower tool holder through a planar bearing, and the lower end face of the upper tool holder and the upper end face of the lower tool holder are rotatably connected through a planar bearing.

[0014] In summary, the beneficial effects of this invention are:

[0015] Through the arrangement of a central shaft, upper sliding sleeve, lower sliding sleeve, upper tool holder, lower tool holder, left-hand rotating tool, right-hand rotating tool, locking hole, locking element, and tower spring, the upper and lower layers of tools can cut into the supply pipe from the inner wall. Guided by the beveled surface of the tool blades, the upper and lower layers of tools rotate and cut from opposite directions, with the cuts eventually intersecting to sever the supply pipe, achieving maximum recovery of the supply pipe. The tools can retract inward, and the locking element engages in the locking hole, preventing the tools from unfolding during the lifting process and ensuring smooth lifting and recovery of the pipe cutter. In addition, the inclusion of a gravity-operated release hammer effectively prevents the tools from getting stuck and unable to be lowered. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0017] Figure 1 This is a schematic diagram of a liquid supply pipe cutter in the unfolded state according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of a liquid supply pipe cutter in the retracted state according to an embodiment of the present invention.

[0019] Figure 3 This is a cross-sectional view of the upper cutter holder in a liquid supply pipe cutter according to an embodiment of the present invention.

[0020] Figure 4 This is a cross-sectional view of the lower cutter holder in a pipe cutting tool for a liquid supply pipe according to an embodiment of the present invention.

[0021] Reference numerals: 1-Central shaft, 2-Lifting lug, 31-Upper lock nut, 32-Lower lock nut, 4-Gravity release hammer, 41-Hammer sleeve, 42-First counterweight, 43-Fasting bolt, 44-Hollow groove, 5-Second counterweight, 6-Third counterweight, 7-Planar bearing, 8-Upper sliding sleeve, 9-Lower sliding sleeve, 10-Upper tool holder, 11-Lower tool holder, 12-Left-handed tool, 13-Right-handed tool, 14-Upper tool hole, 15-Lower tool hole, 16-Positioning groove, 17-Positioning protrusion, 18-Lock hole, 19-Lock fastener, 20-Tower spring. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0024] Please see Figure 1 , Figure 2 , Figure 3 and Figure 4 This invention provides an internal pipe cutter for a liquid supply pipe, comprising a central shaft 1. A gravity-driven release hammer 4 and a sliding sleeve 9 are respectively disposed at both ends of the central shaft 1. An upper sliding sleeve 8 is rotatably connected to the upper end face of the sliding sleeve 9, and the upper sliding sleeve 8 and the lower sliding sleeve 9 are coaxially arranged. An upper tool holder 10 and a lower tool holder 11 are slidably connected to the inner walls of the upper sliding sleeve 8 and the lower sliding sleeve 9, respectively. Damping is provided between the tool holder and the sliding sleeve, so that the relative position of the tool holder and the sliding sleeve remains unchanged during uniform movement. The upper tool holder 10 and the lower tool holder 11 are both provided with positioning grooves 16 on their sides. The inner walls of the upper sliding sleeve 8 and the lower sliding sleeve 9 are both connected with positioning protrusions 17. The positioning protrusions 17 are slidably connected with the corresponding positioning grooves 16. The central shaft 1 passes through the upper tool holder 10 and the lower tool holder 11. The lower end of the central shaft 1 is connected with a lower locking nut 32. The lower locking nut 32 is rotatably connected to the lower tool holder 11. The upper tool holder 10 and the lower tool holder 11 are rotatably connected. Several left-handed tools 12 are hinged to the side of the upper tool holder 10, and several right-handed tools 13 are hinged to the side of the lower tool holder 11. The tools can be rotated and unfolded. The upper sliding sleeve 8 has an upper cutter hole 14 on its side, and the lower sliding sleeve 9 has a lower cutter hole 15 on its side. A locking element 19 is hinged to the lower end of the lower cutter holder 11. The lower sliding sleeve 9 also has a locking hole 18 on its side. A tower spring 20 is installed between the locking element 19 and the lower cutter holder 11. The tower spring 20 is used to push the locking element 19 into the locking hole 18. After the liquid supply pipe is cut off, the pipe cutter is lowered. The upper cutter holder 10 and the lower cutter holder 11 move downward relative to the sliding sleeve, and the unfolded cutter retracts. The locking element 19 is exactly at the locking hole 18 and unfolds by the action of the spring, preventing the cutter from unfolding again during the lifting process.

[0025] In this embodiment of the invention, both the upper cutter holder 10 and the lower cutter holder 11 are provided with a central hole. The upper cutter holder 10 and the lower cutter holder 11 are sleeved on the outside of the central shaft 1. Two left-handed cutters 12 are installed on the upper cutter holder 10, spaced 180° apart, and three right-handed cutters 13 are installed on the lower cutter holder 11, spaced 120° apart. The different angles ensure that while the upper cutter cuts into the freezing tube, at least two of the lower cutters also cut into the freezing tube, and simultaneously rotate and cut the liquid supply tube while in the lifting state.

[0026] In this embodiment of the invention, both the left-handed cutter 12 and the right-handed cutter 13 have a 7.5mm cutting edge (divided into left-angled and right-angled cutters). The cutters are flat-edged with rounded tips, making them sturdy and less prone to breakage. The cutting edges are designed with a 3-degree upward angle, making it easier to cut into the liquid supply tube. The rotation of the cutter can form a circle with a diameter of 78mm, which can effectively cut through a liquid supply tube with a specification of Φ75×6mm. Moreover, while the cutting edge of one side of the cutter completely cuts through the wall of the liquid supply tube, the cutting edge of the other side can still completely cut through the wall of the other side of the liquid supply tube.

[0027] In this embodiment of the invention, the gravity-driven knife-removing hammer 4 includes a hammer sleeve 41 and a first counterweight 42. The top of the hammer sleeve 41 is hemispherical to prevent it from rubbing against the inner clamp of the freezing pipe or the short circuit inside the supply pipe during the lifting of the pipe cutter, thus avoiding difficulty in lifting. The first counterweight 42 is fixedly installed on the inner wall of the hammer sleeve 41 by fastening bolts 43. The interior of the first counterweight 42 is provided with a hollow groove 44. The upper end of the central shaft 1 is connected to a locking nut 31, which can move back and forth in the hollow groove 44 without disengaging from it. After the pipe cutter cuts the supply pipe, by repeatedly lifting and lowering the gravity-driven knife-removing hammer 4 at the top of the pipe cutter, the knife stuck in the cut of the supply pipe is removed under the hammering action, facilitating the next step of knife retrieval.

[0028] In this embodiment of the invention, a second counterweight 5 is connected to the top end of the inner wall of the upper sliding sleeve 8, and a third counterweight 6 is connected to the lower end of the inner wall of the lower sliding sleeve 9. Both the second counterweight 5 and the third counterweight 6 are fixedly installed by fastening bolts 43. When pulled upward, the sliding sleeve will press down on the unfolded blades under the action of the counterweights, increasing the unfolding force of each blade and making it easier to cut into the liquid supply pipe.

[0029] In this embodiment of the invention, the upper surface of the third counterweight 6 is provided with a groove for accommodating the lower lock nut 32, the bottom surface of the third counterweight 6 is fixedly connected with a lifting lug 2, and the top surface of the gravity release hammer 4 is fixedly connected with a lifting lug 2 for connecting a steel wire rope.

[0030] In this embodiment of the invention, the upper end face of the lower lock nut 32 is rotatably connected to the lower end face of the lower tool holder 11 via a plane bearing 7, and the lower end face of the upper tool holder 10 and the upper end face of the lower tool holder 11 are rotatably connected via a plane bearing 7.

[0031] The working process of this invention embodiment is as follows: In the operation of cutting the liquid supply pipe, the cutting depth is determined, and the pipe cutter is lowered to the cutting position by the length of the steel wire rope connecting the pipe cutter. When the pipe cutter is lowered into the liquid supply pipe, it is lowered at a uniform speed to ensure that the relative positions of the cutter holder and the sliding sleeve remain unchanged. When cutting the pipe, firstly, the pipe cutter is pulled up, and the upper cutter holder 10 and the lower cutter holder 11 move upward relative to the sliding sleeve. The cutter extends out from the cutter hole, and the upper and lower layers of unfolded cutters cut into the liquid supply pipe from the inner wall. Guided by the beveled surface of the cutter blade, the upper and lower layers of cutters rotate and cut from two opposite directions, and the cuts finally intersect, cutting off the liquid supply pipe. After the pipe is cut, the gravity-assisted release hammer 4 at the top of the pipe cutter is raised and lowered back and forth using a steel wire rope. Under the hammering action, the blade stuck in the cut of the supply pipe is removed. Then the pipe cutter is lowered. The bottom of the pipe cutter touches the cut end of the supply pipe or the inner pipe clamp of the frozen pipe and stops, while the blade holder continues to slide down. The upper blade holder 10 and the lower blade holder 11 move downward relative to the sliding sleeve, and the unfolded blade retracts. At the same time, the locking element 19 is inserted into the locking hole 18, and the pipe cutter can be lifted and retracted from the supply pipe. Finally, the supply pipe is retrieved.

[0032] While several embodiments and examples of the present invention have been described for those skilled in the art, these embodiments and examples are provided as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

[0033] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A pipe cutter for a liquid supply pipe, comprising a central shaft (1), characterized in that, At both ends of the central shaft (1), a gravity-driven ejector hammer (4) and a sliding sleeve (9) are respectively provided. The upper end face of the sliding sleeve (9) is rotatably connected to an upper sliding sleeve (8). The inner walls of the upper sliding sleeve (8) and the sliding sleeve (9) are respectively slidably connected to an upper tool holder (10) and a lower tool holder (11). The sides of the upper tool holder (10) and the lower tool holder (11) are provided with positioning grooves (16). The inner walls of the upper sliding sleeve (8) and the sliding sleeve (9) are connected to positioning protrusions (17). The positioning protrusions (17) are slidably connected to the corresponding positioning grooves (16). The central shaft (1) passes through the upper tool holder (10) and the lower tool holder (11). The lower end of the central shaft (1) is connected to a lower lock nut (32). The lower locking nut (32) is rotatably connected to the lower tool holder (11), and the upper tool holder (10) and the lower tool holder (11) are rotatably connected. Several left-handed tools (12) are hinged to the side of the upper tool holder (10), and several right-handed tools (13) are hinged to the side of the lower tool holder (11). The upper sliding sleeve (8) has an upper tool hole (14) on its side, and the lower sliding sleeve (9) has a lower tool hole (15) on its side. A locking fastener (19) is hinged to the lower end of the lower tool holder (11), and a locking hole (18) is also provided on the side of the lower sliding sleeve (9). A tower spring (20) is installed between the locking fastener (19) and the lower tool holder (11). The tower spring (20) is used to push the locking fastener (19) into the locking hole (18).

2. The pipe cutter for the liquid supply pipe according to claim 1, characterized in that, Both the upper tool holder (10) and the lower tool holder (11) are provided with a central hole. The upper tool holder (10) and the lower tool holder (11) are sleeved on the outside of the central shaft (1). Two left-handed tools (12) are installed on the upper tool holder (10), and three right-handed tools (13) are installed on the lower tool holder (11).

3. The pipe cutter for the liquid supply pipe according to claim 1, characterized in that, The heads of both the left-handed cutting tool (12) and the right-handed cutting tool (13) have a 7.5mm cutting edge. The cutting tool is a flat-edged round-headed tool with a 3-degree elevation angle.

4. The pipe cutter for the liquid supply pipe according to claim 1, characterized in that, The gravity-driven hammer (4) includes a hammer sleeve (41) and a first counterweight (42). The top of the hammer sleeve (41) is hemispherical. The first counterweight (42) is fixedly installed on the inner wall of the hammer sleeve (41) by fastening bolts (43). The interior of the first counterweight (42) is provided with a hollow groove (44). The upper end of the central shaft (1) is connected to a locking nut (31). The locking nut (31) can move in the hollow groove (44).

5. The supply pipe inlet cutter according to claim 1, characterized in that, The upper sliding sleeve (8) is connected to the top of the inner wall of the second counterweight (5), and the lower sliding sleeve (9) is connected to the lower end of the inner wall of the third counterweight (6). The second counterweight (5) and the third counterweight (6) are both fixedly installed by fastening bolts (43).

6. The supply pipe inlet cutter according to claim 1, characterized in that, The upper surface of the third counterweight (6) is provided with a groove, the bottom surface of the third counterweight (6) is fixedly connected with a lifting lug (2), and the top surface of the gravity-driven hammer (4) is fixedly connected with a lifting lug (2).

7. The pipe cutter for the liquid supply pipe according to claim 1, characterized in that, The upper end face of the lower lock nut (32) is rotatably connected to the lower end face of the lower tool holder (11) through a plane bearing (7), and the lower end face of the upper tool holder (10) and the upper end face of the lower tool holder (11) are rotatably connected through a plane bearing (7).

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