A freezing device and a construction method for tunnel liquid nitrogen freezing water plugging construction

Abstract

The application discloses a freezing device and a construction method for liquid nitrogen freezing water blocking construction in a tunnel. The freezing device comprises a freezing device main body, a driving mechanism and a guide rail. The guide rail is fixedly installed on the freezing device main body. The driving mechanism comprises a gear, the gear is engaged with the gear teeth arranged on the guide rail and forms a transmission pair. During construction, the freezing part is put into the tunnel to be constructed when the freezing device is in a folded state. Then, the freezing device is converted from the folded state to an unfolded state. Finally, liquid nitrogen is continuously poured into the left and right freezing pipes until the water in the tunnel to be constructed is frozen. Through the foldable double-fan structure, the guide rail-gear driving, the waterproof power system and the heat insulation design, the freezing range adaptability of the traditional freezing device is improved, the unfolding stability is improved, and the reliability in a humid environment is improved. The freezing device has the advantages of high construction efficiency, high reliability and strong adaptability.

Description

Technical Field

[0001] This invention relates to the field of ground freezing construction technology. Specifically, it relates to a freezing device and construction method for liquid nitrogen freezing and water plugging construction in tunnels. Background Technology

[0002] Traditional liquid nitrogen freezing technology is mainly used for ground freezing in underground engineering. Its basic principle is to utilize the large amount of heat absorbed when liquid nitrogen changes from a liquid to a gaseous state inside a freezing pipe, thereby rapidly cooling and freezing the surrounding water-bearing soil and rock, forming a large-area, continuous frozen soil wall. In scenarios such as mines, foundation pits, and large tunnel excavation, this method is primarily used to improve the overall strength and stability of the strata and to prevent groundwater inflow, thus providing a safe and stable support structure for subsequent construction.

[0003] However, due to differences in construction objectives and freezing zone requirements, the liquid nitrogen freezing technology used for water plugging in drainage tunnels differs significantly from that used in traditional ground freezing. Traditional ground freezing focuses on freezing large areas to form a continuous frozen soil structure to support the surrounding soil and resist external pressure; while the main purpose of water plugging in drainage tunnels is to quickly form localized ice plugs in confined spaces to ensure a dry environment during construction or maintenance. In ground freezing, a uniform and continuous distribution of frozen soil is required to provide overall structural support; while water plugging in drainage tunnels emphasizes that the freezing range should be specifically adapted to the tunnel's cross-sectional dimensions to achieve full-range water plugging.

[0004] Currently, the liquid nitrogen freezing technology available for water-blocking construction in drainage tunnels is relatively limited. This is mainly because existing technologies and equipment focus on freezing large areas of the ground, failing to adequately meet the specific requirements of localized water sealing within narrow tunnels. Therefore, there is an urgent need to develop a freezing device structure and its construction method specifically designed for water-blocking construction in drainage tunnels. This would allow for ground-extending lowering, flexible adaptation to tunnel dimensions, and the rapid formation of a reliable ice barrier, thereby ensuring a safe and dry construction environment within the tunnel. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to provide a freezing device and construction method for liquid nitrogen freezing and water plugging construction in tunnels, so as to solve the problems of poor adaptability of freezing range and low reliability of driving mechanism when traditional freezing devices are used for water plugging and freezing construction in tunnels.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A freezing device for liquid nitrogen freezing and water plugging construction in tunnels includes a freezing device body, a drive mechanism, and a guide rail; the guide rail is fixedly installed on the freezing device body; the drive mechanism includes a gear, which meshes with the teeth provided on the guide rail to form a transmission pair; the freezing device body includes a left-side freezing tube and a right-side freezing tube; both the left-side and right-side freezing tubes include a disc-shaped freezing section;

[0008] When the freezer is in the folded state, the gear remains stationary, and at least a portion of the freezing sections of the left and right freezing tubes overlap. When the gear rotates, the right freezing tube slides relative to the left freezing tube along the length of the guide rail, causing the freezer to switch between folded and unfolded states. This freezer achieves folding / unfolding state switching through the meshing transmission of the gear and guide rail teeth, solving the problem of insufficient unfolding stability in traditional freezers. In the folded state, it is easy to transport into the tunnel; when unfolded, the double freezing tubes cover a larger area, significantly improving construction efficiency. Furthermore, the relative sliding between the left and right freezing tubes during unfolding occurs in a plane, avoiding the disturbance of sewage in the tunnel under construction caused by the page-like unfolding, which could lead to a decrease in freezing effect.

[0009] The aforementioned freezing device for liquid nitrogen freezing and water plugging construction in tunnels comprises a left-side freezing pipe and a right-side freezing pipe, both of which are single-pipe systems. Furthermore, each of the left-side and right-side freezing pipes includes a liquid inlet and a gas outlet.

[0010] The two openings of the left-side freezing tube are the left-side liquid inlet and the left-side air outlet, respectively; the left-side freezing tube includes a left-side liquid inlet, a left-side freezing section and a left-side air outlet connected in sequence.

[0011] The two ports of the right-side freezing tube are the right-side liquid inlet and the right-side air outlet, respectively; the right-side freezing tube includes a right-side liquid inlet, a right-side freezing section and a right-side air outlet connected in sequence.

[0012] The right-side freezing tube has the same shape and size as the left-side freezing tube.

[0013] The aforementioned freezing device for liquid nitrogen freezing and water plugging construction in tunnels comprises a left-side freezing pipe and a right-side freezing pipe, both of which are "b"-shaped. The lower part of the "b" shape is a semi-circular freezing section, and the upper part is a straight pipe-shaped liquid inlet and air outlet. The left-side liquid inlet, left-side air outlet, right-side liquid inlet, and right-side air outlet are parallel to each other, and the left-side liquid inlet, left-side air outlet, right-side liquid inlet, and right-side air outlet all face the same direction. The disc surfaces of the left-side freezing section and the right-side freezing section are parallel to each other, and the curved edge of the semi-circle of the left-side freezing section faces the opposite direction to the curved edge of the semi-circle of the right-side freezing section. When the freezer is in the deployed state, the frontal projections of the left and right freezing pipes are symmetrical with respect to the centerline of the freezer; and the liquid inlet, air outlet, liquid inlet, and air outlet of the left and right pipes are all adjacent to the centerline of the freezer; when the freezer is in the folded state, the distance between the air outlets of the left and right pipes is equal to the radius of the semicircle of the freezing section; this design allows the freezing section to adapt to the shape of the tunnel cross-section when the freezer is deployed, and the freezer is relatively narrow when folded, making it easy to lower into tunnel maintenance manholes with small diameters.

[0014] The aforementioned freezing device for liquid nitrogen freezing and water plugging construction in tunnels has a groove-shaped guide rail, which is fixedly installed on the plate surface of the freezing part and arranged perpendicular to the air outlet. The number of guide rails is one or two, and the teeth are set on the inner bottom wall of at least one guide rail. The teeth are evenly distributed along the length direction of the guide rail, and the extension direction of the groove between two adjacent teeth is perpendicular to the length direction of the guide rail.

[0015] The rotation axis of the gear is perpendicular to the length direction of the guide rail, and the rotation axis of the gear is perpendicular to the disk surface of the left sector freezing part and the disk surface of the right sector freezing part.

[0016] The aforementioned freezing device for liquid nitrogen freezing and water plugging construction in tunnels comprises two guide rails, including a left-side guide rail and a right-side guide rail. Both the left-side and right-side guide rails have J-shaped cross-sections. Teeth are provided on the inner bottom walls of both the left-side and right-side guide rails. The left-side and right-side guide rails are identical in shape and size. The left-side guide rail is fixedly mounted on a disc surface of the left-side freezing section, and the right-side guide rail is mounted on a disc surface of the right-side freezing section. The disc surface of the left-side freezing section with the left-side guide rail is opposite to the disc surface of the right-side freezing section with the right-side guide rail. The inner bottom wall of the right-side guide rail is opposite to the inner bottom wall of the left-side guide rail. The gear is located between the inner bottom walls of the right-side and left-side guide rails.

[0017] The aforementioned freezing device for liquid nitrogen freezing and water plugging construction in tunnels includes multiple gears arranged along the length of the guide rails. The freezing device uses two guide rails for transmission, and the multiple gears positioned between the two rails enhance the stability and synchronization of the freezing device during deployment and folding. The design of multiple gears distributed along the length of the guide rails disperses the transmission load, preventing excessive force at a single point. Furthermore, the multiple gears improve transmission smoothness, maintaining the deployment accuracy of the freezing device even with slight deformation of the guide rails.

[0018] The aforementioned freezing device for liquid nitrogen freezing and water plugging construction in tunnels includes a drive mechanism that further comprises a waterproof hydraulic pump and a hydraulic motor. The waterproof hydraulic pump is fixed to the guide rail, and a hydraulic transmission connection is established between the waterproof hydraulic pump and the hydraulic motor. The hydraulic motor is driven by the gear. The use of a hydraulically driven motor eliminates the risk of electrical leakage associated with traditional electric drives in humid environments.

[0019] The aforementioned freezing device for liquid nitrogen freezing and water plugging construction in tunnels has its left-side liquid inlet, left-side air outlet, right-side liquid inlet, and right-side air outlet all covered with a heat insulation layer. This heat insulation layer effectively blocks external heat transfer and reduces liquid nitrogen loss.

[0020] A method for constructing a drainage tunnel using liquid nitrogen freezing to block water involves using a freezing device as described above. During construction, with the freezing device in a folded state, the freezing part is placed into the tunnel to be constructed. Then, the freezing device is changed from a folded state to an unfolded state. Finally, liquid nitrogen is continuously injected into the left and right freezing pipes until the water in the tunnel to be constructed freezes.

[0021] The aforementioned liquid nitrogen freezing and water-blocking construction method for drainage tunnels involves adjusting the expansion degree of the freezer from a folded to an unfolded state by regulating the sliding distance of the right-side freezing pipe relative to the left-side freezing pipe along the length of the guide rail. This adjustment adapts the freezer to the inner diameter of the tunnel under construction. By controlling the expansion degree through adjusting the sliding distance of the right-side pipe, the freezer can be adapted to tunnels with different inner diameters. This design breaks through the limitations of traditional equipment specifications, achieving "one machine for multiple uses." The flexible expansion and adjustment mechanism reduces the need for different equipment models, lowers construction costs, and simultaneously improves adaptability to various working conditions.

[0022] The technical solution of the present invention achieves the following beneficial technical effects:

[0023] 1. This invention provides a freezing device for liquid nitrogen freezing and water plugging construction in tunnels. The arrangement of the left and right freezing tubes of this freezing device allows it to be folded, and the width of the folded freezing device is relatively small, effectively reducing the inner diameter of the lowering channel required when lowering the freezing device into the tunnel to be constructed. Simultaneously, relying on gear and guide rail transmission, the left and right freezing tubes can unfold in the tunnel to be constructed. During unfolding, the relative sliding between the left and right freezing tubes occurs in a plane, avoiding the disturbance of sewage in the tunnel by page-like unfolding, which would reduce the freezing effect. The unfolding degree of the freezing device provided in this invention is adjustable, allowing it to adapt to tunnels with different inner diameters. The freezing range of the freezing device can be specifically adapted to the cross-sectional dimensions of the tunnel, improving the sealing and water seal effect of the frozen area. Optionally, the freezer can use a dual-rail and multiple-gear design to distribute the transmission load and synchronously drive the left and right freezing tubes, achieving smooth unfolding and folding of the left and right freezing tubes. Furthermore, the freezer uses a waterproof hydraulic pump as its power source, resulting in high transmission efficiency, strong adaptability, and stable operation in humid environments, ensuring the freezer's normal operation. The freezer provided in this invention is easy to operate and possesses high structural stability and reliability.

[0024] 2. The freezing device and construction method provided by this invention can flexibly adapt to tunnels of different inner diameters, meeting the needs of liquid nitrogen freezing and water plugging construction in tunnels in different scenarios. By quickly unfolding and folding the freezing device, a reliable ice-blocking barrier can be formed in a short time, ensuring the safety and dryness of the construction environment inside the tunnel. The freezing device and construction method provided by this invention are simple to operate, requiring no complex equipment and processes, thus reducing construction difficulty and cost. Attached Figure Description

[0025] Figure 1 A schematic diagram of the front view of the right-side freezing tube in Embodiment 1 of the present invention;

[0026] Figure 2 A schematic diagram of the front view of the left-side freezing tube in Embodiment 1 of the present invention;

[0027] Figure 3 A front view of the freezer in the folded state in Embodiment 1 of the present invention;

[0028] Figure 4 A top view of the process by which the freezer in Embodiment 1 of the present invention changes from a folded state to an unfolded state;

[0029] Figure 5 A schematic diagram showing the positional relationship between the guide rail and the drive mechanism when the freezer is in a folded state in Embodiment 1 of the present invention;

[0030] Figure 6 Side view of the left fan rail in Embodiment 1 of the present invention;

[0031] Figure 7 A bottom view of the right sector guide rail in Embodiment 1 of the present invention;

[0032] Figure 8 Front view of the right sector guide rail in Embodiment 1 of the present invention;

[0033] Figure 9 Side view of the right sector guide rail in Embodiment 1 of the present invention;

[0034] Figure 10 A front view of the freezer in Embodiment 1 of the present invention during the process of switching between a folded state and an unfolded state;

[0035] Figure 11 A schematic diagram of the structure of the left and right freezing tubes of the freezer in Embodiment 2 of the present invention;

[0036] Figure 12 A schematic diagram of the freezer in the unfolded state after being lowered into the tunnel to be constructed in Embodiment 4 of the present invention;

[0037] Figure 13 A schematic diagram showing the positional relationship between the guide rail, gear, and waterproof hydraulic pump during the unfolding process of the freezer in Embodiment 3 of the present invention.

[0038] The reference numerals in the diagram are as follows: 1-Left sector freezing tube; 101-Left sector liquid inlet; 102-Left sector air outlet; 103-Left sector liquid inlet; 104-Left sector freezing section; 105-Left sector air outlet; 2-Right sector freezing tube; 201-Right sector liquid inlet; 202-Right sector air outlet; 203-Right sector liquid inlet; 204-Right sector freezing section; 205-Right sector air outlet; 3-Left sector guide rail; 4-Right sector guide rail; 5-Gear; 6-Gear; 7-Waterproof hydraulic pump; 8-Hydraulic motor. Detailed Implementation

[0039] Example 1

[0040] This embodiment provides a freezing device for liquid nitrogen freezing and water plugging construction in tunnels. The freezing device includes the following structure:

[0041] 1. Freezer body

[0042] The freezer body consists of a left-side freezing tube 1 and a right-side freezing tube 2. Both include a liquid inlet, a disc-shaped freezing section, and an air outlet, and their structures, shapes, and dimensions are completely identical.

[0043] like Figure 1The image shows the right-side freezing pipe 2. The right-side freezing pipe 2 is a curved single pipe. The two inlets of the right-side freezing pipe 2 are the right-side liquid inlet 201 and the right-side air outlet 202. The right-side freezing pipe 2 includes a right-side liquid inlet 203, a right-side freezing section 204, and a right-side air outlet 205 connected in sequence. The overall shape of the right-side freezing pipe 2 is "b". The lower part of the "b" shape is a semi-circular freezing section (i.e., the right-side freezing section 204), and the upper part consists of the parallel right-side liquid inlet 203 and right-side air outlet 205. The right-side freezing section 204 is a coil, while the right-side liquid inlet 203 and right-side air outlet 205 are both straight pipes. The right-side liquid inlet 201 and right-side air outlet 202 are located at the ends of the right-side liquid inlet 203 and the right-side air outlet 205, respectively, which are the top of the "b" shape.

[0044] like Figure 2 As shown, the left-side freezing pipe 1 is also a curved single pipe. The two inlets of the left-side freezing pipe 1 are the left-side liquid inlet 101 and the left-side air outlet 102. The left-side freezing pipe 1 includes a left-side liquid inlet 103, a left-side freezing section 104, and a left-side air outlet 105 connected in sequence. The left-side liquid inlet 101 and the left-side air outlet 102 are respectively located at the ends of the left-side liquid inlet 103 and the left-side air outlet 105. The overall shape of the left-side freezing pipe 1 is also "b" shaped.

[0045] The outer walls of the left fan liquid inlet section 103, the left fan air outlet section 105, the right fan liquid inlet section 203, and the right fan air outlet section 205 are all wrapped with a heat insulation layer.

[0046] The left fan liquid inlet 101, left fan air outlet 102, right fan liquid inlet 201, and right fan air outlet 202 all face the same direction. The left fan freezing section 104 and the right fan freezing section 204 partially overlap, and the disk surfaces of the left fan freezing section 104 and the right fan freezing section 204 are parallel to each other. The curved edge of the semicircle of the left fan freezing section 104 faces the opposite direction to the curved edge of the semicircle of the right fan freezing section 204. Figure 3 The diagram shows the positions of the left and right freezing tubes in the freezer when it is in a folded state. Figure 12 The image shows the positions of the left and right freezing tubes in the freezer when it is in the deployed state. When the freezer is in the deployed state, the frontal projections of the left and right freezing tubes are symmetrical.

[0047] In the pipes forming the freezing section, the distance between the outer walls of adjacent pipes should be consistent, and the distance between the outer walls of adjacent pipes should not be too large, not exceeding twice the thickness of the frozen wall developed outside the pipe. Otherwise, the freezing section will not be able to form a seamless "ice plate" and will not be able to achieve the water-blocking effect. The shape and radius of the left and right freezing sections can be flexibly adjusted according to the cross-sectional shape and diameter of the tunnel to be constructed. However, when adjusting the radius, the working condition after the freezer is placed in the tunnel to be constructed must also be considered. That is, after the freezer is deployed, the distance between the semi-circular curved edge of the left and right freezing sections and the inner wall of the tunnel to be constructed should be less than or equal to the thickness of the frozen wall developed outside the pipe at the semi-circular curved edge.

[0048] 2. Guide rail

[0049] In this embodiment, the guide rails include a left fan guide rail 3 and a right fan guide rail 4. The left fan guide rail 3 is fixedly installed on a disc surface of the left fan freezing part 104, and the right fan guide rail 4 is installed on a disc surface of the right fan freezing part 204. When the freezer is in a folded state, the disc surface of the left fan freezing part 104 on which the left fan guide rail 3 is installed is opposite to the disc surface of the right fan freezing part 204 on which the right fan guide rail 4 is installed.

[0050] like Figure 5 The diagram shows the positional relationship between the right fan guide rail 4 and the right fan guide rail 5 when the freezer is in the folded state. In this embodiment, the only difference between the left and right fan guide rails is the presence or absence of teeth 5 on their surfaces; all other dimensions and structures are identical.

[0051] The following explanation uses the right sector guide rail 4 as an example.

[0052] The right fan guide rail 4 is groove-shaped, and its cross-section is J-shaped. That is, the right fan guide rail 4 is approximately a J-shaped groove. The teeth 5 are set on the inner bottom wall of the J-shaped groove, and the two side walls of the J-shape play a limiting role for the gear.

[0053] like Figure 7 The figure shows a bottom view of the right sector guide rail 4. As can be seen from the figure, the teeth 5 are evenly distributed along the length direction of the right sector guide rail 4; on the right sector guide rail 4, the extension direction of the groove between two adjacent teeth 5 is perpendicular to the length direction of the right sector guide rail 4.

[0054] like Figure 8 and Figure 9 These are the front view and side view of the right fan guide rail 4, respectively. Figure 6 The image shown is a side view of the left fan rail 3.

[0055] like Figure 5As shown, in the freezer provided in this embodiment, the surface of the right fan guide rail 4 where the teeth 5 are located (i.e., the inner bottom wall of the J-shaped groove) faces downwards, and the bottom of the groove of the left fan guide rail 3 (i.e., the inner bottom wall of the J-shaped groove) faces upwards, that is, the inner bottom wall of the right fan guide rail 4 is opposite to the inner bottom wall of the left fan guide rail 3. The left fan guide rail 3 and the right fan guide rail 4 are arranged in parallel.

[0056] 3. Drive mechanism

[0057] like Figure 5 As shown, the drive mechanism includes a gear 6, a waterproof hydraulic pump 7, and a hydraulic motor 8. The waterproof hydraulic pump 7 is fixed below the left fan guide rail 3, and is hydraulically connected to the hydraulic motor 8. The hydraulic motor 8 is driven by the gear 6 and is fixed on the left fan guide rail 3. The rotation axis of the gear is perpendicular to the length direction of the left fan guide rail 3, and also perpendicular to the disc surface of both the left fan freezing part 104 and the right fan freezing part 204. The gear 6 is located between the inner bottom wall of the right fan guide rail 4 and the inner bottom wall of the left fan guide rail 3. The gear 6 meshes with the teeth 5 on the right fan guide rail 4, forming a transmission pair between the gear and the right fan guide rail 4. Both the left fan guide rail 3 and the right fan guide rail 4 are J-shaped grooves with their openings facing each other. Together, they limit the position of the gear 6 located in the J-shaped groove. At the same time, under the gravity of the right fan freezing tube 2, the right fan guide rail 4 presses the gear 6 downward, so that the gear 6 closely meshes with the teeth 5 on the right fan guide rail 4.

[0058] like Figure 4 This is a top view of the freezer in this embodiment during the process of changing from a folded state to an unfolded state. The leftmost part of the figure is a top view of the freezer in the folded state. Figure 10 This is a front view of the freezer in this embodiment during the process of switching between the folded state and the unfolded state.

[0059] like Figure 4 and Figure 10 As shown, when the freezer is in the folded state, the gear 6 remains stationary, and the left fan freezing part 104 and the right fan freezing part 204 partially overlap. Figure 4 and Figure 10 The process from left to right in the middle represents the process of the freezer changing from a folded state to an unfolded state. During this process, the hydraulic motor 8 drives the gear 6 to rotate clockwise, and the gear 6 drives the right-side freezing tube 2 to move along the length of the right-side guide rail 4 to the right side of the figure through the right-side guide rail 4. Figure 10The process from right to left in the diagram represents the transition of the freezer from an unfolded state to a folded state. During this process, the hydraulic motor 8 drives the gear 6 to rotate counterclockwise, and the gear 6 drives the right-side freezing tube 2 to move along the length of the right-side guide rail 4 to the left side of the diagram. That is, when the gear rotates, the right-side freezing tube 2 slides relative to the left-side freezing tube 1 along the length of the guide rail, and the freezer transitions from a folded state to an unfolded state, or vice versa.

[0060] In this embodiment, when the freezer is deployed in the tunnel to be constructed, the movement range of the left and right freezing pipes 1 and 2 is entirely within a tunnel cross-section. The disturbance to the sewage within the tunnel is primarily planar. Other deployment methods (such as page-style opening and closing) may cause hemispherical or other forms of large-scale disturbance to the sewage within the tunnel. The deployment method of the freezer in this embodiment helps reduce disturbance to the sewage within the tunnel, facilitating precise positioning of the freezer in the sewage.

[0061] In this embodiment, the left fan guide rail does not have teeth, and the hydraulic motor is mounted on the left fan guide rail. During the gear-driven movement of the right fan guide rail, the left fan guide rail can provide some support to the right fan guide rail, which is beneficial for the smooth unfolding of the freezer. In some other embodiments, only one guide rail can be used, such as the right fan guide rail 4, and the hydraulic motor 8 is mounted on the left fan freezing part, while the waterproof hydraulic pump 7 is mounted on the right fan guide rail 4. In this case, the hydraulic pipeline between the hydraulic motor 8 and the waterproof hydraulic pump 7, which performs the hydraulic transmission function, is a flexible pipeline, which can adapt to the working condition where the distance between the hydraulic motor and the waterproof hydraulic pump changes continuously when the freezer switches between folded and unfolded states.

[0062] Alternatively, it can also be in Figure 5 Based on the structure shown, teeth 5 are added to the bottom of the groove of the left fan guide rail 3, and a fixing device for fixing the hydraulic motor 8 is added. This fixing device is independent of the freezer and fixes the relative position of the hydraulic motor 8 and the tunnel maintenance well. In the folded state, the teeth of the gear 6 and the left fan guide rail 3, as well as the teeth of the gear 6 and the right fan guide rail 4, are meshed with each other. When the hydraulic motor 8 drives the gear 6 to rotate clockwise, the left fan guide rail 3 drives the left fan freezer to move to the left side of the figure until the teeth on the left fan guide rail 3 disengage from the gear 6. At this time, the gear 6 can still drive the right fan freezing tube 2 to move to the right side of the figure along the length direction of the right fan guide rail 4 through the right fan guide rail 4, and the freezer can still be unfolded normally.

[0063] Example 2

[0064] This embodiment provides a freezing device for liquid nitrogen freezing and water plugging construction in tunnels. The freezing device in this embodiment is basically the same in structure as the freezing device in Embodiment 1, except that: in this embodiment, the freezing parts of the left-side freezing pipe 1 and the right-side freezing pipe 2 are both rectangular discs; when the freezing device is in a folded state, the left-side freezing part 104 and the right-side freezing part 204 almost completely overlap.

[0065] like Figure 11 The diagram shows the structure of the left-side freezing tube 1 and the right-side freezing tube 2 in this embodiment (the freezer is currently in the process of transitioning from a folded state to an unfolded state). The freezer in this embodiment is suitable for tunnels with a rectangular cross-section. In other embodiments, the shape and size of the freezing section can be adjusted according to the shape and cross-sectional area of ​​the tunnel.

[0066] In both Example 1 and this example, the left and right freezing tubes in the freezer are arranged symmetrically (meaning that when the freezer is fully extended, the frontal projections of the left and right freezing tubes are symmetrical). When the freezer is in the extended state, the left liquid inlet, left air outlet, right liquid inlet, and right air outlet are all close to the center line of the freezer. When the freezer is in the folded state, the distance between the left liquid inlet (left air outlet) and the right liquid inlet (right air outlet) reaches its maximum. The reason for this design is that tunnel maintenance manholes are generally located directly above the tunnel centerline, and the diameter of the tunnel maintenance manhole used to lower the freezing device is smaller than the tunnel diameter. Therefore, the freezing device is usually lowered in a folded state. When the liquid inlet and air outlet are located on one side of the freezing pipe as much as possible, and the left and right freezing pipes are stacked in a mirror image symmetrically, as long as the folded freezing device can be lowered into the smaller diameter tunnel maintenance manhole, the distance between the left liquid inlet (left air outlet) and the right liquid inlet (right air outlet) gradually decreases when the freezing device is unfolded. This will prevent the tunnel maintenance manhole from restricting the movement of the liquid inlet and air outlet, thus avoiding the problem of the freezing device not being able to fully unfold.

[0067] In other embodiments, the left and right freezing pipes in this embodiment can be arranged in the same direction, so that when the freezer is in the folded state, the left and right freezing parts will completely overlap. When the left and right freezing pipes are arranged in the same direction, it is acceptable as long as it does not affect the lowering (from the ground to the tunnel to be constructed) and unfolding of the freezer.

[0068] It should be noted that the left-side freezing pipe 1 and the right-side freezing pipe 2 in Examples 1 and 2 can be made by welding multiple pipes together in sequence, or by bending a single pipe. When multiple pipes are connected and welded together in sequence, only the inner and outer couplings need to be welded together, which is convenient for on-site splicing and installation. At the same time, the liquid inlet and gas outlet sections can be flexibly lengthened according to the distance from the ground to the tunnel.

[0069] Example 3

[0070] The freezer in this embodiment is a further improvement upon the freezer in Embodiment 1. For example... Figure 13 As shown, in this embodiment, teeth 5 are provided on the bottom of the groove of the left fan guide rail 3 and the bottom of the groove of the right fan guide rail 4, and two gears 6 are added. Each gear is driven by a hydraulic motor 8, and the three gears are arranged along the length of the guide rail, as shown. Figure 13 As shown. The hydraulic motors 8 are all fixedly mounted on a fixed device independent of the freezer.

[0071] In this embodiment, multiple gears are arranged along the length of the guide rail, which is more conducive to maintaining structural stability during the freezing process.

[0072] Example 4

[0073] In this embodiment, the freezing device from Embodiment 1 is used for liquid nitrogen freezing and water plugging construction in the drainage tunnel. During construction, the freezing device, in a folded state, is lowered from the ground into the tunnel to be constructed, ensuring that both the left and right freezing sections 104 and 204 are inside the tunnel. Then, the waterproof hydraulic pump 7 and hydraulic motor 8 are activated, causing the gear 6 to rotate, thus changing the freezing device from a folded state to an unfolded state. Figure 12 The image shows a freezing device in its deployed state inside a tunnel to be constructed.

[0074] After the freezer is deployed, liquid nitrogen is injected into the left-side freezing pipe 1 and the right-side freezing pipe 2 through the left-side inlet 101 and the right-side inlet 201, respectively. The liquid nitrogen exchanges heat with the water in the tunnel under construction at the left-side freezing section 104 and the right-side freezing section 204, and then vaporizes. The nitrogen gas is discharged from the left-side outlet 102 and the right-side outlet 202, causing the water in the tunnel under construction to gradually freeze. Liquid nitrogen is continuously injected to maintain the frozen state of the water in the tunnel under construction.

[0075] When it is necessary to remove the freezer from the tunnel under construction, stop filling with liquid nitrogen and allow the water in the tunnel to thaw naturally. Then, restart the waterproof hydraulic pump 7 and hydraulic motor 8 to rotate the gear 6, and the freezer will change from the unfolded state to the folded state to facilitate the removal of the freezer from the tunnel under construction.

[0076] When the freezer changes from the folded state to the unfolded state, the right freezing tube 2 slides relative to the left freezing tube 1 along the length of the guide rail. At this time, the degree of unfolding of the freezer can be adjusted by adjusting the sliding distance of the right freezing tube 2 relative to the left freezing tube 1 along the length of the guide rail, so that the freezer can adapt to tunnels with different inner diameters.

[0077] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A freezing device for liquid nitrogen freezing and water plugging construction in tunnels, characterized in that, The device includes a freezer body, a drive mechanism, and a guide rail; the guide rail is fixedly mounted on the freezer body; the drive mechanism includes a gear (6), which meshes with the teeth (5) on the guide rail to form a transmission pair; the freezer body includes a left-side freezing tube (1) and a right-side freezing tube (2); both the left-side freezing tube (1) and the right-side freezing tube (2) include a disc-shaped freezing section; When the freezer is in the folded state, the gear (6) remains stationary, and at least a portion of the freezing part of the left fan freezing tube (1) and the freezing part of the right fan freezing tube (2) overlap each other; when the gear (6) rotates, the right fan freezing tube (2) slides relative to the left fan freezing tube (1) along the length direction of the guide rail, and the freezer changes from the folded state to the unfolded state, or from the unfolded state to the folded state. The left-side freezing pipe (1) and the right-side freezing pipe (2) are both single pipes, and the left-side freezing pipe (1) and the right-side freezing pipe (2) also include a liquid inlet and a gas outlet, respectively. The left-side freezing tube (1) and the right-side freezing tube (2) are both "b" shaped. The lower part of the "b" shape is the semi-circular freezing part, and the upper part is the straight tube-shaped liquid inlet and gas outlet. The guide rail is groove-shaped and is fixedly installed on the plate surface of the freezing part, and is arranged perpendicular to the air outlet.

2. The freezing device for liquid nitrogen freezing and water plugging construction in tunnels according to claim 1, characterized in that, The two ports of the left-side freezing tube (1) are the left-side liquid inlet (101) and the left-side air outlet (102); the left-side freezing tube (1) includes a left-side liquid inlet (103), a left-side freezing part (104) and a left-side air outlet (105) connected in sequence. The two ports of the right-side freezing tube (2) are the right-side liquid inlet (201) and the right-side air outlet (202); the right-side freezing tube (2) includes a right-side liquid inlet (203), a right-side freezing part (204) and a right-side air outlet (205) connected in sequence. The right-side freezing tube (2) has the same shape and size as the left-side freezing tube (1).

3. The freezing device for liquid nitrogen freezing and water plugging construction in tunnels according to claim 2, characterized in that, The left fan liquid inlet (103), the left fan air outlet (105), the right fan liquid inlet (203), and the right fan air outlet (205) are parallel to each other, and the left fan liquid inlet (101), the left fan air outlet (102), the right fan liquid inlet (201), and the right fan air outlet (202) all face the same direction; the disk surface of the left fan freezing part (104) and the disk surface of the right fan freezing part (204) are parallel to each other, and the curved edge of the semicircle of the left fan freezing part (104) faces the opposite direction to the curved edge of the semicircle of the right fan freezing part (204).

4. The freezing device for liquid nitrogen freezing and water plugging construction in tunnels according to claim 3, characterized in that, The number of guide rails is one or two, and the teeth (5) are arranged on the inner bottom wall of at least one of the guide rails; the teeth (5) are evenly distributed along the length direction of the guide rail, and the extension direction of the tooth groove between two adjacent teeth (5) is perpendicular to the length direction of the guide rail. The rotation axis of the gear (6) is perpendicular to the length direction of the guide rail, and the rotation axis of the gear (6) is perpendicular to the disk surface of the left fan freezing part (104) and the disk surface of the right fan freezing part (204).

5. The freezing device for liquid nitrogen freezing and water plugging construction in tunnels according to claim 4, characterized in that, The guide rails consist of two rails, including a left fan guide rail (3) and a right fan guide rail (4); the cross-section of the left fan guide rail (3) and the right fan guide rail (4) are both J-shaped, and the teeth (5) are provided on the inner bottom wall of the left fan guide rail (3) and the inner bottom wall of the right fan guide rail (4); the left fan guide rail (3) and the right fan guide rail (4) are identical in shape and size; the left fan guide rail (3) is fixedly installed on a plate of the left fan freezing part (104). The right fan guide rail (4) is mounted on a disc surface of the right fan freezing part (204), and the disc surface of the left fan freezing part (104) on which the left fan guide rail (3) is mounted is opposite to the disc surface of the right fan freezing part (204) on which the right fan guide rail (4) is mounted. The inner bottom wall of the right fan guide rail (4) is opposite to the inner bottom wall of the left fan guide rail (3). The gear (6) is located between the inner bottom wall of the right fan guide rail (4) and the inner bottom wall of the left fan guide rail (3).

6. The freezing device for liquid nitrogen freezing and water plugging construction in tunnels according to claim 5, characterized in that, There are multiple gears (6), and the multiple gears (6) are arranged along the length direction of the guide rail.

7. The freezing device for liquid nitrogen freezing and water plugging construction in tunnels according to claim 4, characterized in that, The drive mechanism also includes a waterproof hydraulic pump (7) and a hydraulic motor (8), wherein the waterproof hydraulic pump (7) is fixed on the guide rail, the waterproof hydraulic pump (7) and the hydraulic motor (8) are hydraulically connected, and the hydraulic motor (8) and the gear (6) are driven together.

8. The freezing device for liquid nitrogen freezing and water plugging construction in tunnels according to any one of claims 2-7, characterized in that, The outer walls of the left fan liquid inlet (103), the left fan air outlet (105), the right fan liquid inlet (203), and the right fan air outlet (205) are all wrapped with a heat insulation layer.

9. A method for constructing a drainage tunnel using liquid nitrogen freezing to stop water leakage, characterized in that, Construction is carried out using the freezer as described in claim 1; during construction, the freezer is placed into the tunnel to be constructed while it is in a folded state, and then the freezer is changed from a folded state to an unfolded state. Finally, liquid nitrogen is continuously injected into the left freezing pipe (1) and the right freezing pipe (2) until the water in the tunnel to be constructed freezes.

10. The liquid nitrogen freezing and water-blocking construction method for drainage tunnels according to claim 9, characterized in that, When the freezer is changed from a folded state to an unfolded state, the unfolding degree of the freezer is adjusted to be compatible with the inner diameter of the tunnel to be constructed by adjusting the sliding distance of the right freezing pipe (2) relative to the left freezing pipe (1) along the length direction of the guide rail.

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