Rounding and transportation construction process in large pressure steel pipe hole of hydropower station

Abstract

The invention relates to the technical field of hydropower station pressure steel pipe installation, in particular to a hydropower station large pressure steel pipe in-hole circle forming and transportation construction process which comprises the following steps that tiles are transported to a circle forming station at the intersection of a construction branch hole and a main hole; the tiles are subjected to circle assembling and welding at the circle assembling station to form a whole section of pressure steel pipe; a rolling device is arranged on a stiffening ring of the pressure steel pipe; the pressure steel pipe provided with the rolling device is hoisted to a rail car; the rail car is dragged to advance to an intersection of the to-be-installed main hole and the construction adit along the adit rail; the pressure steel pipe is transferred from the rail car to a main hole rail laid in a to-be-installed main hole, the wheel track of the rolling device is matched with the track gauge of the main hole rail, and the center elevation of the transferred pressure steel pipe is the designed installation elevation; and the pressure steel pipe is pulled to a mounting station along the main hole track. Therefore, the problem that the transportation time efficiency is difficult to guarantee in the limited space is solved, and the construction quality and the construction safety are guaranteed.

Description

Technical Field

[0001] This invention belongs to the technical field of hydropower station pressure steel pipe installation, specifically relating to a construction process for assembling and transporting large pressure steel pipes inside tunnels in hydropower stations. Background Technology

[0002] In hydropower station construction, pressure steel pipes serve as the core structure of the water conveyance system, and their installation quality and construction efficiency directly affect the safe and stable operation of the entire power station. In particular, the installation of pressure steel pipes in upward bends, downward bends, horizontal tunnels, vertical shafts, and inclined shafts has always been a critical and challenging process in water conservancy engineering construction due to complex geological conditions and limited space. According to current construction technical specifications, pressure steel pipe installation mainly employs two processes, but both have significant technical limitations in practical applications.

[0003] The first traditional method is the in-tunnel assembly process, which involves transporting the tiles into the tunnel, assembling them into circles on the installation work surface, and then installing them in place. This method is mainly suitable for large-scale pressure steel pipe projects, and its technical logic stems from the scenario where the cross-sectional dimensions of traffic tunnels and construction adits cannot meet the transportation requirements of whole sections of pressure steel pipes. In actual construction, the "tile assembly" technique is used to complete the rolling and splicing of individual steel pipe sections inside the tunnel. Although this process can solve the transportation problem of large components, it has obvious drawbacks: when installing the upper bend and vertical shaft sections, the assembly process and the steel pipe sliding process in the same work tunnel conflict spatially, making parallel operations impossible and significantly extending the construction period. At the same time, the installation of steel pipes in the upper bend, vertical shaft, lower bend, and horizontal tunnel sections all rely on trolleys for support. During the assembly and turning process, temporary ear plates need to be welded to the outer wall of the steel pipe, and steel wire ropes are connected by bow-shaped shackles for hoisting and turning. This operation is prone to causing direct friction between the steel wire rope and the stiffening ring of the steel pipe. According to safety operating procedures, such frictional contact may not only damage the stiffening ring structure (the stiffening ring is a key ring structure for improving the stability of steel pipes against external pressure), but also pose a high safety risk of wire rope wear and breakage.

[0004] The second traditional method is the external assembly and transportation process, which involves first assembling and welding the pressure steel pipes at a prefabrication site outside the tunnel, and then transporting the entire pipe section to the installation location inside the tunnel. This method is suitable for small and medium-sized pressure steel pipe projects, provided that the dimensions of the traffic tunnel and construction adit can meet the transportation requirements of the entire pipe section. External assembly can utilize standardized tooling to ensure welding quality and reduce cross-interference between work surfaces inside the tunnel. However, this process has rigid limitations: for large pressure steel pipes or projects with limited construction adit dimensions, the transport diameter and weight of the entire pipe section far exceed the carrying capacity of the passageway, rendering this method completely unsuitable.

[0005] A comprehensive analysis of existing technologies reveals that both methods suffer from insurmountable technical bottlenecks: the in-tunnel assembly method is limited by procedural interference and safety hazards, making it impossible to balance construction efficiency and operational safety; the out-of-tunnel assembly method is constrained by the size of the transportation channel, significantly limiting its applicability. In practical engineering, when the cross-sectional size of the construction adit is smaller than that of the pressure steel pipe, existing technologies cannot achieve both out-of-tunnel prefabrication and transportation of the entire steel pipe and efficient and safe construction through in-tunnel assembly, creating a technical dilemma for the installation of large pressure steel pipes.

[0006] Therefore, in response to the above-mentioned technical problems, it is necessary to optimize and improve the transportation scheme inside the pressure steel pipe tunnel of the hydropower station, so as to solve the problem of difficulty in ensuring transportation timeliness under confined space, and ensure construction quality and construction safety. Summary of the Invention

[0007] The purpose of this invention is to provide a construction process for assembling and transporting large pressure steel pipes inside a tunnel in a hydropower station, so as to solve the problem of difficulty in ensuring transportation timeliness under limited space in the prior art, and to ensure construction quality and construction safety.

[0008] A construction process for assembling and transporting large pressure steel pipes inside a tunnel in a hydropower station is applicable to situations where the cross-sectional dimension of the construction adit is smaller than the diameter of the pressure steel pipe after assembly. This construction process includes the following steps:

[0009] S1. Transport the tiles to the assembly station at the intersection of the construction branch tunnel and the main tunnel, and weld the tiles into a whole section of pressure steel pipe at the assembly station.

[0010] S2. Install a rolling device on the stiffening ring of the pressure steel pipe;

[0011] S3. Hoist the pressure steel pipe equipped with the rolling device onto the railcar;

[0012] S4. Pull the railcar along the branch tunnel track to the intersection of the main tunnel to be installed and the construction branch tunnel;

[0013] S5. Transfer the pressure steel pipe from the railcar to the main tunnel track laid in the main tunnel to be installed. The wheel gauge of the rolling device matches the track gauge of the main tunnel track. After the transfer, the center elevation of the pressure steel pipe is the design installation elevation.

[0014] S6. Pull the pressure steel pipe along the main tunnel track to the installation position.

[0015] Optionally, the assembly station in step S1 is equipped with an assembly platform, which is composed of multiple I-beams fixed to the bedrock by expansion bolts. Adjustment shims are set under each I-beam, and the flatness error of the platform is ≤2mm. The rock mass above the assembly station is pre-embedded with anchors, including turning anchors for turning the steel pipes and assembly anchors for positioning and unloading the assembly.

[0016] Optionally, two turning anchors are provided, arranged at intervals along the center line of the construction adit, with the spacing equal to the diameter of the pressure steel pipe; the turning operation of the pressure steel pipe is achieved in the following way: the wire rope of the turning winch passes around the guide pulley connected to the turning anchor, and is connected to the turning lifting device through a shackle, the turning lifting device being connected to the center position between the two stiffening rings on the pressure steel pipe.

[0017] Alternatively, the turning hoist includes a steel chain and connectors at both ends thereto, wherein one connector is connected to a lug welded to a stiffening ring via a shackle, and the other connector is connected to the wire rope of the turning winch via a shackle.

[0018] Optionally, the assembly anchor is connected to an electric hoist for unloading the tiles, adjusting their alignment during assembly, and hoisting the steel pipes after assembly.

[0019] Alternatively, in step S2, the rolling device is welded and fixed to the stiffening ring after the installation position is determined by a special positioning template. Two sets of rolling devices are symmetrically installed on each stiffening ring, and their wheel spacing is equal to the track gauge of the main tunnel track.

[0020] Alternatively, the rolling device includes a roller frame, a roller shaft, a roller, and a fastening assembly; the roller is supported on the roller shaft by two roller bearings installed in its wheel hole; the roller frame is provided with a groove that matches the thickness of the stiffening ring.

[0021] Alternatively, the railcar is equipped with an upper track, the gauge of which is the same as that of the main tunnel track; the railcar is pulled by a traction winch to run on the branch tunnel track.

[0022] Alternatively, when the pressure steel pipe is transferred from the railcar to the main tunnel track in step S5, the positioning wedge is removed first, and the track on the railcar is fully connected with the track of the installation tunnel, with the track of the railcar and the track of the installation tunnel on the same plane.

[0023] Optionally, the circular welding in step S1 adopts CO2 gas shielded welding process, and the inner longitudinal seam welding, outer wall root cleaning and outer longitudinal seam welding are performed in sequence, and finally the butt welding of the stiffening ring between adjacent tiles is completed; the pressure steel pipe is made of high-strength steel, and the area environment is controlled at the circular welding station.

[0024] The advantages of this invention over the prior art are as follows:

[0025] Through the above technical solution, the construction process for assembling and transporting large pressure steel pipes inside the tunnel of a hydropower station, as described in this invention, utilizes a specialized turning lifting tool (steel chain with butterfly buckles and shackles). The connection point is positioned at the center between two stiffening rings, ensuring no frictional contact between the lifting tool (steel chain) and the steel pipe body, thus eliminating safety hazards. The assembly platform is firmly fixed to the bedrock after leveling with shims, ensuring the stability of the assembly work's reference point. Key facilities such as the anchor system, winch, and railcar have all undergone targeted design and rigorous construction, forming a stable and reliable construction system and reducing overall operational risks.

[0026] By setting up the pipe assembly station at the intersection of the construction adit and the main tunnel, all preliminary work, including pipe assembly, welding, and accessory installation, can be completed outside the main tunnel. This allows for parallel operations such as steel pipe sliding and installation inside the main tunnel, avoiding the problems of interference and lack of synchronization between operations on the same work surface in traditional pipe assembly methods, and significantly shortening the critical path duration.

[0027] By pre-installing rolling devices precisely on the stiffening rings and ensuring that their wheel gauge perfectly matches the main tunnel track gauge, while the track gauge on the railcar also matches the main tunnel track, the center elevation of the pressure steel pipe after being transferred from the railcar to the main tunnel track is the designed installation elevation. This eliminates the need for cumbersome jacking, lowering, or axis adjustments before subsequent circumferential welding or fixing. Utilizing winches, electric hoists, and railcars for the main lifting and transportation of heavy objects reduces reliance on manual labor, lowers labor intensity, and accelerates work speed. Centralized assembly and welding at intersection workstations provides a relatively better working environment, which is beneficial for ensuring quality and improving efficiency.

[0028] This invention allows for regional environmental control, preheating, and strict temperature management at the assembly station, effectively preventing cold cracking in high-strength steel welding and improving weld quality reliability. This solves the technical problem of the cross-sectional dimension of the construction support tunnel being smaller than the diameter of the pressure steel pipe after assembly. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0030] Figure 1This invention provides a schematic diagram of the planar layout of pressure pipelines in the construction process of assembling and transporting large pressure steel pipe tunnels in hydropower stations.

[0031] Figure 2 A schematic diagram of the main view structure of the anchor in the construction process of assembling and transporting large pressure steel pipe tunnels in hydropower stations provided by the present invention.

[0032] Figure 3 A top view of the overhead anchor structure in the construction process of assembling and transporting large pressure steel pipe tunnels in hydropower stations provided by the present invention.

[0033] Figure 4 This is a schematic diagram of the main view structure of the construction support tunnel in the construction process of the internal assembly and transportation of large pressure steel pipe tunnels in hydropower stations provided by the present invention.

[0034] Figure 5 This is a schematic diagram of the side view of the construction support tunnel transportation structure in the construction process of the large pressure steel pipe tunnel in a hydropower station provided by the present invention.

[0035] Figure 6 A schematic diagram of the roller device and pressure steel pipe assembly in the construction process of assembling and transporting large pressure steel pipes in a hydropower station tunnel, provided by the present invention.

[0036] Figure 7 This invention provides a template diagram for the installation and marking of roller devices in the construction process of assembling and transporting large pressure steel pipe tunnels in hydropower stations.

[0037] Figure 8 A schematic diagram of the main view structure of the railcar in the construction process of assembling and transporting large pressure steel pipe tunnels in hydropower stations provided by the present invention.

[0038] Figure 9 A side view of the track vehicle structure in the construction process of assembling and transporting large pressure steel pipe tunnels in hydropower stations provided by the present invention.

[0039] Figure 10 This invention provides a schematic diagram of the lifting points for turning over the pressure steel pipe during the construction process of assembling and transporting large pressure steel pipes inside the tunnel of a hydropower station.

[0040] The markings and corresponding component names in the attached diagram are as follows: 100-Main tunnel, 200-Main tunnel track, 300-Construction adit, 400-Adit track, 500-Turning winch, 600-Traction winch, 700-Anchor, 701-Circular anchor, 702-Turning anchor, 800-Guide pulley, 900-Electric hoist, 1000-Circular platform, 1100-Pressure steel pipe, 1101-Helping ring, 1200 - Rolling device, 1201 Roller frame, 1202 Roller, 1203 Roller shaft, 1204 Roller bearing, 1205 Shaft end plate, 1206 Fastener, 1300 Railcart, 1301 Upper rail, 1302 Rail frame, 1303 Rail wheel, 1400 Installation line template, 1401 Installation line, 1500 Turning lifting device, 1501 Bow-shaped shackle, 1502 Butterfly buckle. Detailed Implementation

[0041] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that while the description of these embodiments is intended to aid in understanding the invention, it does not constitute a limitation thereof. The specific structural and functional details disclosed herein are only for describing exemplary embodiments of the invention. However, the invention can be embodied in many alternative forms and should not be construed as being limited to the embodiments described herein.

[0042] According to the first aspect of this disclosure, a construction process for assembling and transporting large pressure steel pipes inside a tunnel in a hydropower station is provided, wherein... Figure 1-10 Specific embodiments thereof are shown.

[0043] See Figure 1-10 As shown, the construction process for assembling and transporting the large pressure steel pipe inside the tunnel of this hydropower station is applicable to situations where the cross-sectional dimension of the construction adit 300 is smaller than the diameter of the pressure steel pipe after assembly (1100). The construction process includes the following steps:

[0044] S1. Transport the tiles to the assembly station at the intersection of the construction branch tunnel 300 and the main tunnel 100, and weld the tiles together at the assembly station to form a whole section of pressure steel pipe 1100.

[0045] S2. Install a rolling device 1200 on the stiffening ring 1101 of the pressure steel pipe 1100;

[0046] S3. Hoist the pressure steel pipe 1100 equipped with the rolling device 1200 onto the railcar 1300;

[0047] S4. The track vehicle 1300 is pulled along the branch tunnel track 400 to the intersection of the main tunnel 100 to be installed and the construction branch tunnel 300;

[0048] S5. Transfer the pressure steel pipe 1100 from the railcar 1300 to the main tunnel track 200 laid in the main tunnel 100 to be installed. The wheel gauge of the rolling device 1200 matches the track gauge of the main tunnel track 200. After the transfer, the center elevation of the pressure steel pipe 1100 is the design installation elevation.

[0049] S6. Pull the pressure steel pipe 1100 to the installation position along the main tunnel track 200.

[0050] Through the above technical solution, the construction process for assembling and transporting large pressure steel pipes inside the tunnel of a hydropower station, as described in this invention, utilizes a specialized turning hoist 1500 (steel chain with butterfly buckle 1502 and shackle), with its connection point positioned at the center between the two stiffening rings 1101. This ensures that the hoist (steel chain) has no frictional contact with the steel pipe body, eliminating safety hazards. The assembly platform 1000 is firmly fixed to the bedrock after being leveled by adjusting shims, ensuring the stability of the assembly work's reference. Key facilities such as the anchor 700 system, winch, and railcar 1300 have all undergone targeted design and rigorous construction, forming a stable and reliable construction system and reducing overall operational risks.

[0051] By setting the assembly station at the intersection of the construction adit 300 and the main tunnel 100, all preliminary work, including assembly, welding, and accessory installation, can be completed outside the main tunnel 100. This allows the steel pipe laying and installation processes inside the main tunnel 100 to be carried out in parallel, avoiding the problems of mutual interference and lack of synchronization in the same work area of ​​the traditional in-tunnel assembly method, and significantly shortening the critical path duration.

[0052] By pre-installing the rolling device 1200 precisely on the stiffening ring 1101 and ensuring that its wheel track is completely consistent with the track gauge of the main tunnel track 200, while the track gauge on the railcar 1300 also matches that of the main tunnel track 200, the center elevation of the pressure steel pipe 1100 after being transferred from the railcar 1300 to the main tunnel track 200 is the design installation elevation. Subsequent circumferential welding or fixing can proceed without the need for cumbersome jacking, lowering, or axis adjustments. The use of winches, electric hoists 900, and railcars 1300 for the main lifting and transportation of heavy objects reduces reliance on manpower, lowers labor intensity, and accelerates work speed. Centralized assembly and welding at the intersection workstation provides a relatively better working environment, which is conducive to ensuring quality and improving efficiency.

[0053] This invention allows for regional environmental control, preheating, and strict temperature management at the assembly station, effectively preventing cold cracking in high-strength steel welding and improving weld quality reliability. This solves the technical problem that the cross-sectional dimension of the construction support tunnel (300mm) is smaller than the diameter of the pressure steel pipe (1100mm) after assembly.

[0054] Specifically, the assembly station in step S1 is equipped with an assembly platform 1000, which consists of multiple I-beams fixed to the bedrock by expansion bolts. Adjustment shims are placed under each I-beam, and the platform's flatness error is ≤2mm. Above the assembly station, anchors 700 are pre-embedded in the rock mass, including a turning anchor 702 for turning the steel pipe and an assembly anchor 701 for positioning and unloading during assembly. This provides a high-precision reference plane for the assembly and welding of the pressure steel pipe 1100, effectively ensuring the roundness of the steel pipe and the quality of the longitudinal weld.

[0055] Furthermore, two turning anchors 702 are provided, arranged at intervals along the center line of the construction adit 300, with the spacing equal to the diameter of the pressure steel pipe 1100; the turning operation of the pressure steel pipe 1100 is achieved in the following way: the wire rope of the turning winch 500 passes around the guide pulley 800 connected to the turning anchor 702, and is connected to the turning lifting device 1500 through a shackle, the turning lifting device 1500 being connected to the center position between the two stiffening rings 1101 on the pressure steel pipe 1100.

[0056] Furthermore, the turning hoist 1500 includes a steel chain and connectors connected to both ends thereto, wherein one end of the connector is connected to a lug plate welded to a stiffening ring 1101 via a shackle, and the other end of the connector is connected to the wire rope of the turning winch 500 via a shackle.

[0057] In one embodiment, the round anchor 701 is connected to an electric hoist 900 for unloading the tiles, adjusting their alignment during assembly, and hoisting the steel pipes after assembly.

[0058] Specifically, in step S2, the rolling device 1200 is welded and fixed to the stiffening ring 1101 after the installation position is determined by a special positioning template. Two sets of rolling devices 1200 are symmetrically installed on each stiffening ring 1101, and their wheel gauge is equal to the track gauge of the main tunnel track 200.

[0059] Furthermore, the rolling device 1200 includes a roller frame 1201, a roller shaft 1203, a roller 1202, and a fastening assembly. The roller 1202 is supported on the roller shaft 1203 by two roller bearings 1204 installed in its wheel hole. The roller frame 1201 is provided with a groove that matches the thickness of the stiffening ring 1101. A special installation template 1400 is used to mark the positioning on the stiffening ring 1101, ensuring the accurate installation position of the rolling device 1200. The groove design on the roller frame 1201 matches the thickness of the stiffening ring 1101, further ensuring installation accuracy.

[0060] In this disclosure, the railcar 1300 is provided with an upper track 1301, the gauge of which is the same as that of the main tunnel track 200; the railcar 1300 is pulled by a traction winch 600 to run on the branch tunnel track 400.

[0061] In this disclosure, when the pressure steel pipe 1100 is transferred from the railcar 1300 to the main tunnel track 200 in step S5, the positioning wedge is removed, and the track on the railcar is fully aligned with the track of the installation hole, with the railcar and the track of the installation hole on the same plane. In this way, the roller 1202 of the rolling device 1200 can be stably positioned on the main tunnel track 200.

[0062] In this disclosure, the circular welding in step S1 adopts CO2 gas shielded welding process, and the inner longitudinal seam welding, outer wall root cleaning and outer longitudinal seam welding are performed in sequence, and finally the butt welding of the stiffening ring 1101 between adjacent tiles is completed; the pressure steel pipe 1100 is made of high-strength steel, and the area environment control is implemented at the circular welding station.

[0063] CO2 gas shielded welding has a much higher deposition efficiency than traditional shielded metal arc welding. It can perform welding continuously and quickly, significantly shortening the welding operation time and improving the rounding efficiency of pressure steel pipes.

[0064] Based on a specific welding sequence, welding is first performed internally, with the large bevel on the inside, which better ensures the fusion quality at the root and the roundness control of the steel pipe. After completing the inner longitudinal seam welding, mechanical root cleaning (such as carbon arc gouging) is performed from the outside to thoroughly remove any potential defects such as incomplete penetration and slag inclusions, and to prepare a good bevel for welding the outer longitudinal seam. This is a key step to ensure full-section penetration and achieve full-penetration welding. The outer longitudinal seam is then welded on the bevel after root cleaning, finally completing the connection of the main weld body. This sequence of "internal welding + root cleaning + external welding" is a standard and reliable process to ensure the internal quality of thick plate welds. After the main longitudinal seam is completed, the butt weld of the stiffening ring 1101 between adjacent tiles is then welded. This sequence can release most of the welding stress of the main longitudinal seam, avoiding excessive constraint of the stiffening ring 1101 on the shrinkage of the main longitudinal seam, thereby reducing overall welding deformation and residual stress.

[0065] It should be noted that the directional terms used, such as "inner" and "outer", refer to "inner" and "outer" relative to the outline of the component. The direction towards the inside of the component is "inner", and the opposite is "outer".

[0066] Example 1

[0067] Please refer to Figure 1-10 The diagram shows a construction process for assembling and transporting a large pressure steel pipe tunnel in a hydropower station, as provided in an embodiment of the present invention. The specific structure is as follows.

[0068] like Figure 1 As shown, taking the pressure pipeline installation project of the Yebatan Hydropower Station's water diversion and power generation system as an example, four main tunnels 100 are laid out in parallel, and one construction adit 300 is set up perpendicular to the main tunnels 100. A circular platform 1000 is set up at the intersection of the No. 1 main tunnel 100 and the construction adit 300. A turning winch 500 is installed in the section of the construction adit 300 between the No. 1 main tunnel 100 and the No. 2 main tunnel 100; on the other side of the No. 1 main tunnel 100, in the construction adit 300, one turning winch 500 and one traction winch 600 are installed.

[0069] like Figure 2 and Figure 3 As shown, at the intersection of the No. 1 main tunnel 100 and the construction adit 300, two turning anchors 702 and three circular anchors 701 are installed; a guide pulley 800 is connected below the turning anchor 702, and the wire rope of the turning winch 500 is wound around this guide pulley 800; an electric hoist 900 is connected below the circular anchor 701.

[0070] like Figure 3 As shown, at the intersection of the No. 1 main tunnel 100 and the construction adit 300, a circular platform 1000 is set up. The circular platform 1000 is based on 9 evenly arranged I-beams. Two adjusting shims are set under each I-beam. The adjusting shims are used to level the I-beams, and the flatness does not exceed 2.0 mm. The I-beams are fixed to the ground with expansion bolts.

[0071] like Figure 4 and Figure 5 As shown, after the pressure steel pipe 1100 is assembled into a circle, it is lifted to a vertical position by two turning winches 500; then the railcar 1300 moves to directly below the pressure steel pipe 1100 and places wedges on both sides of the rolling device 1200.

[0072] like Figure 6 As shown, the rolling device 1200 consists of a roller frame 1201, rollers 1202, roller shafts 1203, roller bearings 1204, shaft end baffles 1205, and fasteners 1206. Two roller bearings 1204 are installed in the wheel holes of each roller 1202. The roller shaft 1203 passes through the roller frame 1201 and the rollers 1202. The shaft end baffles 1205 and fasteners 1206 then assemble the roller shaft 1203, roller frame 1201, and rollers 1202 into a single unit. The notch L3 of the roller frame 1201 has the same thickness as the stiffening ring 1101, and the depth of the notch is exactly the installation depth.

[0073] like Figure 8 and Figure 9 As shown, the railcar 1300 consists of an upper rail 1301, a rail frame 1302, and rail wheels 1303. Figure 8The track gauge L1 in the tunnel is the same as that of the auxiliary track 400. Figure 9 The gauge L2 of the track car 1300 in the tunnel is the same as that of the main tunnel track 200.

[0074] like Figure 10 As shown, a turning hoist 1500 is symmetrically arranged at the center of the pressure steel pipe 1100. The turning hoist 1500 consists of an arc-shaped shackle 1501 and a butterfly buckle 1502. The butterfly buckles 1502 are connected to both ends of the steel chain 1503. One butterfly buckle 1502 is connected to the lug on the stiffening ring 1101 through the arc-shaped shackle 1501, and the other butterfly buckle 1502 is connected to the wire rope of the turning winch 500 through the arc-shaped shackle 1501.

[0075] Example 2

[0076] This embodiment proposes a construction process for assembling and transporting large pressure steel pipes inside a tunnel in a hydropower station. It adopts the main tunnel track 200, branch tunnel track 400, turning winch 500, traction winch 600, anchor 700, guide pulley 800, electric hoist 900, rolling device 1200, track car 1300, installation line template 1400, and turning hoist 1500 from Embodiment 1 to form a construction process for assembling and transporting large pressure steel pipes inside a tunnel in a hydropower station.

[0077] (1) After the tiles are manufactured and inspected at the steel pipe factory, they are transported to the bottom of the anchor 700 by flatbed truck and unloaded by the round anchor 701.

[0078] (2) Use the circular anchor 701 to assemble and reinforce the three tiles. First, weld the inner longitudinal seam using CO2 gas shielded welding; then, after cleaning the root on the outside, weld the outer longitudinal seam using CO2 gas shielded welding. Weld the stiffening rings 1101 between adjacent tiles. After the weld is inspected and approved, use the installation line template 1400 to draw the installation line 1401 of the rolling device 1200 on the stiffening ring 1101, and weld the rolling devices 1200 on the stiffening ring 1101. Install two rolling devices 1200 on each stiffening ring 1101, and install four rolling devices 1200 on each section of steel pipe. The spacing L2 of the rolling devices 1200 on each stiffening ring 1101 is the same as the spacing of the main tunnel track 200.

[0079] (3) The steel pipe is lifted to a vertical position by passing the steel wire ropes of the two turning winches 500 around the guide pulley 800 of the turning anchor 702 and connecting to the turning hoist 1500.

[0080] (4) The railcar 1300 is pulled into position directly below the pressure steel pipe 1100 by the traction winch 600, and wedges are inserted on both sides of the roller 1202 of the rolling device 1200 to fix the steel pipe securely.

[0081] (5) Use the traction winch 600 to pull the railcar 1300 and the pressure steel pipe 1100 to the intersection of the construction adit 300 and the main tunnel 100. Remove the wedges on both sides of the roller 1202 of the rolling device 1200. Pull the pressure steel pipe 1100 onto the main tunnel track 200. The height of the pressure steel pipe 1100 on the main tunnel track 200 is the installation position.

[0082] (6) Repeat serial numbers (1)-(5) to complete the installation of pressure steel pipe 1100.

[0083] Advantages of a construction process for assembling and transporting large pressure steel pipes inside a hydropower station tunnel:

[0084] (1) The turning operation of the pressure steel pipe 1100 is achieved by using the winch wire rope to pass around the guide pulley 800 of the turning anchor 702, so that the pressure steel pipe 1100 can be turned over and erected quickly, which significantly improves the turning efficiency.

[0085] (2) The pressure turning hoist 1500 is located in the middle of the central stiffening ring 1101 of the pressure steel pipe 1100. It uses two steel chains, which are connected at both ends by a butterfly buckle 1502: one end is connected to the lug of the stiffening ring 1101 via a bow-shaped shackle 1501, and the other end is connected to the wire rope via the same bow-shaped shackle 1501. Compared with the traditional method of welding lugs onto the steel pipe and connecting the wire rope via the bow-shaped shackle 1501, this process allows the steel chains to make frictionless contact with the stiffening ring 1101 during the turning of the pressure steel pipe 1100, while maximizing the use of existing space and significantly improving the safety and efficiency of the turning operation.

[0086] (3) The track gauge and height of the track of the railcar 1300 are perfectly matched with those of the main tunnel track 200. By adding a rolling device 1200 to the stiffening ring 1101 of the pressure steel pipe 1100, there is no need to use a trolley for transportation inside the main tunnel 100. Since the pressure steel pipe 1100 is already at the installation height, it can be accurately positioned without adjustment, which significantly improves the installation efficiency.

[0087] (4) The connecting beam on the railcar 1300 adopts an arc structure, which is suitable for transporting pressure steel pipes 1100 with different spacing stiffening rings 1101.

[0088] After the pressure steel pipe 1100 is assembled into a circle, its installation line 1401 is marked using the notch on the installation line template 1400. The width of the notch on the roller frame 1201 is designed to be equal to the thickness of the stiffening ring 1101. By precisely controlling the depth of this notch, the roller frame 1201 can be installed quickly and its positioning accuracy can be ensured, thereby guaranteeing the overall installation accuracy of the pressure steel pipe 1100.

[0089] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0090] Finally, it should be noted that this invention is not limited to the optional embodiments described above, and anyone can derive other various forms of products under the guidance of this invention. The specific embodiments described above should not be construed as limiting the scope of protection of this invention, which should be determined by the claims, and the specification can be used to interpret the claims.

Claims

1. A construction process for in-hole assembling and transporting of large pressure steel pipes of a hydropower station, characterized in that, The construction process is suitable for the working condition that the cross-sectional size of the construction branch hole is smaller than the diameter of the assembled pressure steel pipe, and comprises the following steps. S1, transporting the tile to the assembling circle station at the intersection of the construction branch hole and the main hole, and welding the tile to form an integral pressure steel pipe at the assembling circle station; S2, installing the rolling device on the stiffening ring of the pressure steel pipe; S3, hoisting the pressure steel pipe provided with the rolling device to the rail car; S4, pulling the rail car along the branch hole track to the intersection of the main hole and the construction branch hole to be installed; S5, transferring the pressure steel pipe from the rail car to the main hole track laid in the main hole to be installed, the wheel spacing of the rolling device matches the track gauge of the main hole track, and the center elevation of the pressure steel pipe after transfer is the design installation elevation; S6, pulling the pressure steel pipe along the main hole track to the installation station.

2. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 1, characterized in that, The assembling circle station in step S1 is provided with an assembling circle platform composed of a plurality of I-shaped steel fixed to the bedrock by expansion bolts, and each I-shaped steel is provided with an adjusting pad iron below, and the platform flatness error is ≤2mm; the rock mass above the assembling circle station is pre-buried with a sky anchor, including a turning-over sky anchor for turning over the steel pipe and an assembling circle sky anchor for assembling circle positioning and unloading.

3. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 2, characterized in that, The turning-over sky anchor is provided with two, which are arranged in the direction of the center line of the construction branch hole with a spacing equal to the diameter of the pressure steel pipe; the turning-over operation of the pressure steel pipe is realized by the following mode: the steel wire rope of the turning-over winch is wound around the guide pulley connected to the turning-over sky anchor, and then connected to the turning-over lifting appliance through a shackle, and the turning-over lifting appliance is connected to the center position between the two ring stiffening rings of the pressure steel pipe.

4. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 3, characterized in that, The turning-over lifting appliance comprises a steel chain and connectors connected to both ends of the steel chain, one end of the connector is connected to the ear plate welded on the stiffening ring through a shackle, and the other end of the connector is connected to the steel wire rope of the turning-over winch through a shackle.

5. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 2, characterized in that, The assembling circle sky anchor is connected with an electric hoist, which is used for unloading the tile, adjusting the position during assembling circle, and hoisting the steel pipe after assembling circle.

6. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 1, characterized in that, The rolling device in step S2 is welded and fixed on the stiffening ring after determining the installation position by a special positioning template, and two sets of rolling devices are symmetrically installed on each ring stiffening ring, and the wheel spacing is equal to the track gauge of the main hole track.

7. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 6, characterized in that, The rolling device comprises a roller frame, a roller shaft, a roller and a fastening assembly; the roller is supported on the roller shaft through two roller bearings installed in the wheel hole of the roller; the roller frame is provided with a clamping groove matched with the thickness of the stiffening ring.

8. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 1, characterized in that, The rail car is provided with an upper track, and the track gauge of the upper track is consistent with the track gauge of the main hole track; the rail car is pulled to run on the branch hole track by a pulling winch.

9. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 1, characterized in that, In step S5, the pressure steel pipe is transferred from the rail car to the main hole track, and first, the positioning wedge is removed, the track on the rail car is completely butted with the track of the installation hole, and the track on the rail car and the track of the installation hole are located in the same plane.

10. The in-hole assembling and transporting construction process for large pressure steel pipes of a hydropower station according to claim 1, characterized in that, In step S1, the assembling circle welding adopts CO2 gas shielded welding process, sequentially performs inner longitudinal seam welding, outer wall cleaning and outer longitudinal seam welding, and finally completes the butt welding of the stiffening rings between adjacent tiles; the pressure steel pipe is made of high-strength steel, and regional environmental control is implemented at the assembling circle station during assembling circle welding.

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