A turnout inserting and paving construction method for a ballast line

Abstract

The application discloses a kind of turnout plug-in construction method of existing ballast track, comprising the following steps: S1, determine turnout moving track path;S2, construction preparation;S3, the removal of existing ballast track;S4, moving turnout;S5, lifting turnout;S6, arrangement horizontal displacement device;S7, turnout posture adjustment;S8, turnout into line;S9, backfill ballast;S10, turnout welding;S11, line final adjustment.The beneficial effects of the application are: the simulation optimization of turnout moving track is carried out, the whole turnout moving mode is adopted, the posture is adjusted by horizontal displacement device and fine adjustment device, the existing plug-in condition is broken through, the turnout operation efficiency in the existing ballast track operating line range is improved, the construction of large turnout insertion into existing ballast track in narrow space is realized, and it is especially suitable for large turnout whole long distance longitudinal insertion into existing line construction when site is limited and operation surface is compact.

Description

Technical Field

[0001] This invention relates to the field of track turnout construction technology, and in particular to a method for laying turnouts on existing ballast tracks. Background Technology

[0002] With the continuous deepening and improvement of my country's high-speed rail network construction, a large number of newly built lines need to be connected to existing stations. The installation of turnouts on existing ballast tracks has laid the foundation for another large-scale speed increase, timetable adjustment, and capacity expansion of the railway. Currently, there are many types of turnouts in China. Turnouts are classified by number as 6, 7, 8, 9, 12, 18, and larger numbers (such as 30, 42, and 60). The most commonly used single turnouts on main operating railway lines are No. 9, 12, and 18. Larger number turnouts are mainly used for connecting lines requiring higher siding speeds. Passenger dedicated lines mainly use No. 18 turnouts. No. 6, 7, and 8 turnouts are mainly used for dedicated lines of industrial and mining enterprises or freight yards. For the installation of smaller number turnouts, due to their smaller size, installation can usually be carried out at the designated installation point. However, for larger number turnouts, a corresponding assembly site is usually required for assembly. For the renovation of existing ballasted lines, if the site assembly conditions are relatively good, the insertion environment is relatively spacious, and there is no interference from existing equipment, the insertion operation can be carried out according to existing methods, such as the "first lateral movement and then short-distance longitudinal movement" method and the "one-time pulling and placement of the entire replacement equipment" method. However, not all existing ballasted lines have good insertion conditions. For example, early line designs did not originally include turnouts, but as traffic volume increases, single or even multiple turnouts may be required. Early line locations may encounter complex conditions within the operating line range, such as narrow construction sites, compact work surfaces, or severe interference from existing equipment (signals, overhead contact lines, hard crosses, existing turnout switch machines, transformer boxes, etc.). The existing insertion operation efficiency is low, often requiring multiple lateral and longitudinal adjustments. In particular, the construction technology for inserting No. 42 turnouts into existing ballasted lines has not yet achieved a breakthrough. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for installing turnouts on existing ballasted lines. This method can break through the limitations of existing installation conditions, improve the efficiency of turnout operations within the operating range of existing ballasted lines, and enable the installation of large-number turnouts into existing ballasted lines in confined spaces.

[0004] The objective of this invention is achieved through the following technical solution: a method for installing turnouts on existing ballasted tracks, comprising the following steps:

[0005] S1. Determine the track path for the turnout: Based on the placement position and the direction of turnout movement, determine the optimal track path for the turnout.

[0006] S2. Pre-construction preparation: Utilizing the track window before the insertion point, complete the installation of hard barriers and mark the points at the insertion location. Simultaneously, lay the running rail according to the optimal turnout moving track path. The running rail can be laid in accordance with the existing track laying method. Specifically, place a 2.5m long wooden sleeper at a spacing of no more than 5m, and place a pair of 60cm long short wooden sleepers between the long wooden sleepers. Install special pulleys for rail removal on the long wooden sleepers. Manually use crowbars, rail flippers, etc., to move the 50kg / m tool rail onto the wooden sleeper pulleys, adjust the running track direction, and add 60cm long short sleepers between the long wooden sleepers. Place wooden boards on the short sleepers to level the track. During operation, technicians will determine the running line at 5m points. The running line is designed according to the 5000m radius of the No. 42 turnout guide curve. The distance between the outer edges of the pulleys for rail removal on the long wooden sleepers is controlled at 1435mm±5mm, and the center of the wooden sleepers of the two pulleys is marked in advance. After the running rails are laid, check the level of the track in a timely manner, and control the level within 5mm.

[0007] S3. Removal of existing ballasted track: During the track maintenance window, the existing ballasted track is sawn according to the location of the insertion, and the sawn rails and sleepers in the section where the insertion is located are removed, and the track bed is inspected.

[0008] Based on the impact of existing equipment (contact wire posts, CPIII), as a preferred method, oxy-acetylene cutting is used for cutting the rails at the turnout center, while rail sawing machines are used for other parts as much as possible.

[0009] The bottom inspection of the ballast bed is the most important step in the construction process, and its compliance directly affects the quality of the project after opening. According to the division of ballast cleaning units, and referring to the pre-marked ballast cleaning line 50cm outside the turnout sleepers, ballast cleaning work is carried out simultaneously. Using the existing track surface elevation as a control point, measurement points are pre-marked at 5m intervals to verify the bottom inspection depth, ensuring it is not less than 100mm. This avoids situations where insufficient inspection width or depth prevents the track panels from being lowered.

[0010] S4. Moving Turnouts: Using the laid running rails, the assembled turnouts are moved to the insertion position by a tractor. The turnouts are assembled in their designated assembly areas. Once the turnout sleepers and rails are mostly in place, preparations for turnout assembly begin. The laying sequence is: switch rails and stock rails, frog, and guide rails. First, the theoretical center of the frog is adjusted to the pre-marked position. The positions of the stock rails and switch rails are then adjusted, primarily to ensure the distance between the tip of the switch rail and the theoretical center of the frog. This is generally confirmed using a total station to establish the layout points.

[0011] S5. Lifting the turnout: After the turnout is moved into place, the turnout is lifted by the lifting cylinder group installed on the tractor. Then, a safety block is set up under the turnout, and the tractor and the traveling rail under the turnout are removed.

[0012] S6. Lowering the turnout: A lateral movement device and a movable lifting cylinder assembly are arranged below the turnout. The turnout is lifted by the movable lifting cylinder assembly, removed from the safety stack, and lowered onto the lateral movement device. The movable lifting cylinder assembly is then removed. The lateral movement device adopts the patent number 202323564353.8 published by the applicant, entitled "A lateral movement device for existing line plug-in turnouts". The lateral movement device will not be described in detail here.

[0013] S7. Turnout attitude adjustment: The turnout is adjusted laterally in a large direction using the lateral movement device until the lateral movement distance is less than 2cm. The movable lifting cylinder group is placed under the turnout, and the turnout is lifted by the movable lifting cylinder group. The lateral movement device is then removed. The fine adjustment device is then installed under the turnout, and the turnout is placed on the fine adjustment device. The movable lifting cylinder group is removed, and the turnout is adjusted by the fine adjustment device until the lateral movement distance is less than 5mm, thus completing the turnout attitude adjustment.

[0014] S8. Turnout Entry: Install a movable lifting cylinder assembly below the turnout. Use this assembly to lift the turnout, remove the fine-tuning device, and then, in conjunction with the movable lifting cylinder, control the rail surface elevation of the turnout (using a level). Connect the joint with a clamp plate. The turnout entry is complete. The rail surface elevation control mentioned in step S8 refers to controlling the turnout rail surface elevation based on the existing ballasted track rail surface elevation with a 20mm allowance. A 1‰ slope is applied from the turnout head and tail inwards, with the curved track side controlled 0.5mm lower than the straight track side. In step S8, a 5-8mm weld seam is left at the joint.

[0015] S9. Backfilling ballast: After the turnout is installed, backfill the ballast at the insertion location and tamp and cure it, leaving a weld seam. Remove the movable lifting cylinder during the backfilling process. In step S9, backfill the ballast at the movable lifting cylinder point below the turnout first. The backfilling process is carried out in sections. When backfilling in sections, adjust the elevation and orientation of the turnout.

[0016] S10. Turnout Welding: After tamping and curing meet the standards, welding operations are carried out on the turnouts to the existing ballasted track and the ballasted track to be connected. In step S10, the welding of the turnouts to the existing ballasted track is carried out first, and the welding of the turnouts to the ballasted track to be connected is carried out the next day. Before welding, the turnout rails at the pre-welding points can be ground in advance and wrapped with geotextile to avoid contamination. After the existing track is dismantled and the turnout is in place, the existing track to be welded points should be ground in a timely manner. After manual track maintenance meets the standards and the rail break emergency repair device is removed, the parts to be welded need to be ground again before aluminothermic welding can be carried out. When welding the turnouts and tracks, the protective personnel use warning tape to isolate the aluminothermic welding area to ensure that the aluminothermic welding construction is undisturbed and to ensure the construction progress and quality. At the same time, rain protection measures should be taken when welding the turnouts and tracks.

[0017] S11. Final Adjustment of the Track: After the welding is qualified, the direction and elevation of the track are adjusted by a track shifting machine until the design requirements are met, and the laying operation is completed.

[0018] It should be noted that the following preparatory work should be done before the switch-in construction: 1. Conduct a survey in advance of the location of existing rail welding joints and insulated joints after the switch head is inserted, and complete rail allocation and preparation in advance. At the same time, survey the sections that require sleeper equalization and replacement, and complete sleeper preparation in advance. 2. Measure the rail surface elevation corresponding to the switch head, switch center, and switch tail of the existing line in advance to control the elevation after the new switch is inserted and to ensure the smooth connection of the newly laid connecting line. 3. Set up the 5m point of the switch and the positions of the switch head and switch tail. Use a total station to lay out the 5m point of the switch to the non-working side of the rail of the inserted section and the adjacent track rail, and mark the point number and position on the rail web of the adjacent track rail. 4. Set up various control stakes for adjustment after the switch is longitudinally moved into place, and pay attention to checking the clearance of existing equipment such as signal lights and catenary. 5. Determine the interference range of the switch construction.

[0019] The purpose of this solution is to enable the installation of various types of turnouts within confined spaces, including common No. 18 and No. 42 turnouts. The No. 42 turnout is a large turnout with a straight section exceeding 150 meters in length. Using existing methods, an additional assembly area needs to be constructed at the installation location. If multiple installation points exist on an existing ballasted track, the current method is inefficient and costly. Therefore, this solution addresses the issue of multiple installation points or poor installation conditions (narrow work area, compact work surface, or significant interference from existing equipment). By using a turnout moving track, the turnouts can be transported to the installation points. This track can either connect to a point with suitable installation conditions to establish an assembly area or be directly transported by road to the track. Thus, this solution utilizes existing rail traction vehicles to construct the turnout moving track, enabling the installation of large-number turnouts into existing ballasted tracks within confined spaces. For constructing the turnout moving track alongside existing ballasted tracks, the path layout is crucial. Ideally, the track should be laid out parallel to the existing ballasted track, allowing for direct longitudinal and then lateral movement of the turnout. The movement distance is controllable with minimal adjustment. However, in practice, the turnout track is not parallel to the existing ballasted track. Therefore, this solution uses a method of determining the optimal turnout track path for its layout.

[0020] Determining the optimal turnout moving track path includes the following steps:

[0021] a. Based on the location of the insertion position, mark out the turnout parking area after the turnout is moved longitudinally to the position, and at the same time plan the turnout moving track line from the direction of turnout movement. The turnout moving track line is divided into the inner line S1 located in the turnout parking area and the outer line S2 located outside the turnout parking area.

[0022] b. Simulate the movement of the turnout into place: Simulate the existing ballasted track, the ballasted track to be connected, the turnout parking area, the turnout moving track route, and the turnout moved into place. The lateral movement distance from the turnout head to the existing ballasted track is A1, and the lateral movement distance from the turnout tail of the straight track to the existing ballasted track is A2, where A2≥A1.

[0023] c. Determine the optimal turnout moving track path: If the deviation between A1 and A2 does not exceed 50mm, then retain the existing inner line S1. The optimal turnout moving track path is the inner line S1 and the outer line S2. If the deviation between A1 and A2 is greater than 50mm, adjust the inner line S1 until A1 and A2 are equal. The adjusted inner line is the inner line S3. After determining the inner line S3, adjust the outer line S2 to connect smoothly with the inner line S3. The adjusted outer line is the outer line S4. At this time, the optimal turnout moving track path is the inner line S3 and the outer line S4.

[0024] As can be seen, this scheme first simulates the inner line S1 and the outer line S2. Due to the large size of the large-number turnout (turnout No. 42), if the radius of curvature of the turnout moving track is too small, the turnout will be too heavy and inconvenient to transport. The radius of curvature of the turnout moving track should not be less than 2500m. The inner line S1 and the outer line S2 are determined through on-site surveys. Preferably, the inner line S1 and the outer line S2 should be connected sequentially. Ideally, the inner line S1 and the outer line S2 should be inserted into the turnout parking area as straight as possible or as a curve with a radius of curvature greater than 2500m. By controlling the deviations of A1 and A2 in the simulation software, the lateral movement distance between the turnout and the existing ballasted track after entering the turnout parking area is controlled. Since the inner line S1 and outer line S2 are paths drawn from measured points, the deviations of A1 and A2 are small except in the ideal state (where the turnout moving track is parallel to the existing ballasted track). In other cases, the deviations of A1 and A2 are relatively large. Therefore, this scheme corrects the inner line S1 and outer line S2 to ensure that the adjustment amount of the turnout entering the turnout parking area is controlled in an optimal manner. It should be noted that the outer line S2 includes one or a combination of straight track and curved track. When the outer line S2 connects smoothly with the inner line S1, the radius of curvature should be greater than 2500m. The positions of other outer lines S2 can be determined according to the actual situation, such as tunnels or relocation sites.

[0025] The term "moving to position" refers to moving the turnout head to align with the existing ballast track turnout connection point.

[0026] The fine-tuning device consists of multiple evenly distributed caster wheel assemblies. Each caster wheel assembly includes a lower pad and an upper pad. A base is provided on the lower pad, and the base has at least three mounting slots arranged around its center. A rotating ball is movably mounted in each mounting slot. The rotating balls are at the same elevation and protrude from the base. Each mounting slot has multiple limiting blocks to restrict the rotation of the balls. During turnout attitude adjustment, the lower surface of the upper pad is in close contact with all the rotating balls on the base, and the turnout is placed on the upper surface of the upper pad. Moving the turnout causes the upper pad to rotate the rotating balls, thus achieving a small-range turnout position adjustment. Because large-diameter turnouts are relatively long, they are generally adjusted in sections.

[0027] This solution, by determining the optimal turnout moving track path, can control the maximum lateral movement distance. The optimized moving route effectively controls the number of adjustments and the amount of movement. Furthermore, the turnout moving track can address long-distance movement between the insertion point and the assembled turnout. After the turnout is in place, a lateral movement device moves it to the insertion point, allowing for large-scale lateral movement adjustments. Then, a fine-tuning device performs small-scale position adjustments. After welding, final precision adjustments are made until the design requirements are met.

[0028] The beneficial effects of this invention are: it simulates and optimizes the track for turning points, adopts the method of moving the turning points as a whole, and adjusts the attitude through the lateral movement device and the fine adjustment device, which breaks through the limitations of the existing insertion conditions, improves the efficiency of turning point operation within the existing ballasted line operating range, and realizes the construction of inserting large-number turning points into existing ballasted lines in narrow spaces. It is particularly suitable for the construction of inserting large-number turning points into existing lines over long distances when the site is limited and the working surface is compact. Attached Figure Description

[0029] Figure 1 This is a flowchart illustrating the construction process of the present invention.

[0030] Figure 2 This is a schematic diagram showing the arrangement of the tractor and lifting cylinder assembly of the present invention;

[0031] Figure 3 For the present invention Figure 2 Enlarged schematic diagram of region A in the middle;

[0032] Figure 4 This is a schematic diagram of the optimal turnout moving track path according to the present invention;

[0033] Figure 5 This is a comparative schematic diagram of the optimal turnout moving track path of the present invention;

[0034] Figure 6 This is a schematic diagram of the structure of the fine-tuning device of the present invention;

[0035] Figure 7 This is a schematic diagram showing the installation position of the rotating sphere in the fine-tuning device of the present invention;

[0036] Figure 8 This is a schematic diagram of the limiting block in the fine-tuning device of the present invention.

[0037] In the diagram, 1-lower pad, 2-upper pad, 3-base, 4-mounting groove, 5-rotating sphere, 6-limiting block. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] like Figure 1 As shown, a method for installing turnouts on existing ballasted tracks includes the following steps:

[0040] S1. Determine the track path for the turnout: Based on the placement position and the direction of turnout movement, determine the optimal track path for the turnout. The turnout is turnout number 42.

[0041] S2. Pre-construction preparation: Utilize the daylight window before the insertion point to complete the installation of hard barriers and mark the points at the insertion location, and at the same time lay the running rail according to the optimal turnout moving track path;

[0042] S3. Removal of existing ballasted track: During the track maintenance window, the existing ballasted track is sawn according to the location of the insertion, and the sawn rails and sleepers in the section where the insertion is located are removed and the track bed is inspected.

[0043] S4. Moving Turnouts: Using the laid tracks, the assembled turnouts are moved to the insertion position by a tractor. Specifically, 21 longitudinal moving trolleys (9 driving and 12 driven) are used to move the turnouts 200m to the insertion position. Adjustments are made to the turnouts during the journey, and warning markers are installed simultaneously.

[0044] S5. Lifting the turnout: After the turnout is moved into place, the turnout is lifted by the lifting cylinder group installed on the tractor. Then, a safety stack is set up under the turnout, and the tractor and the traveling rail under the turnout are removed. Short wooden sleepers are placed under the cylinders. The turnout is lifted by 600mm using 48 lifting cylinders. A safety stack is set up, 21 longitudinal transfer trolleys are removed, and a 50 loader is used to remove two 156-meter traveling rails from behind the turnout. The wooden sleepers are then removed.

[0045] S6. Lowering the turnout: A lateral movement device and a movable lifting cylinder group are arranged below the turnout. The turnout is lifted by the movable lifting cylinder group, removed from the safety block, and lowered onto the lateral movement device. The movable lifting cylinder group is then removed.

[0046] S7. Turnout attitude adjustment: The turnout is adjusted laterally in a large direction using the lateral movement device until the lateral movement distance is less than 2cm. The movable lifting cylinder group is placed under the turnout, and the turnout is lifted by the movable lifting cylinder group. The lateral movement device is then removed. Then, a fine adjustment device (48 fine adjustment devices are evenly arranged) is installed under the turnout. The turnout is placed on the fine adjustment device, the movable lifting cylinder group is removed, and the turnout is adjusted by the fine adjustment device until the lateral movement distance is less than 5mm, thus completing the turnout attitude adjustment.

[0047] S8. Turnout Entry: Install a movable lifting cylinder assembly below the turnout. Use this assembly to lift the turnout, remove the fine-tuning device, and then, in conjunction with the movable lifting cylinder, control the rail surface elevation of the turnout. Connect the joint with a clamp plate. The turnout entry is complete. The rail surface elevation control mentioned in step S8 refers to controlling the turnout rail surface elevation based on the existing ballasted track rail surface elevation with a 20mm allowance. A 1‰ slope is applied from the turnout head and tail inwards, with the curved track side controlled 0.5mm lower than the straight track side. In step S8, a 5-8mm weld seam is left at the joint.

[0048] S9. Backfilling ballast: After the turnout is installed, backfill the ballast at the insertion location and tamp and cure it, leaving a weld seam. Remove the movable lifting cylinder during the backfilling process. In step S9, backfill the ballast at the movable lifting cylinder point below the turnout first. The backfilling process is carried out in sections. When backfilling in sections, adjust the elevation and orientation of the turnout.

[0049] S10, Turnout Welding: After the tamping and curing meet the standards, welding operations are carried out on the turnout to the existing ballasted line and the ballasted line to be connected. In step S10, the turnout is welded to the existing ballasted line first, and the turnout is welded to the ballasted line to be connected the next day.

[0050] S11. Final Adjustment of the Track: After the welding is qualified, the direction and elevation of the track are adjusted by a track shifting machine until the design requirements are met, and the laying operation is completed.

[0051] The tractor unit utilizes the CPH-240T hydraulic turnout replacement unit, which features the ability to move and position large-number, heavy-duty turnouts as a whole. Its characteristics include a rational structural design, a split-type structure, lightweight individual units, easy movement, flexible operation, and stable hydraulics. The hydraulic pump station uses a well-known brand engine, ensuring low failure rate and long service life. The hoses feature quick-connect couplings for rapid connection, making it suitable for field operations. It is a replacement for traditional track-lifting equipment, possessing advanced technical performance and meeting the requirements for replacing various types of turnouts. For complex conditions involving inserting No. 42 turnouts into existing lines, only the YZZX-60 hydraulic longitudinal traversing tractor unit needs modification to meet the requirements. The improved hydraulic longitudinal traversing tractor unit has the following significant features: a rational structural design, simple and flexible operation, a clutch-type structure, and forward, reverse, and manual pushing functions, as well as lateral adjustment capabilities. During operation, it can automatically traction and push the longitudinal movement of turnout track panels, eliminating the need for manual pushing. Powered by a high-quality hydraulic motor, it boasts a low failure rate, high traction force, reliable performance, and convenient use and maintenance. The top tray of the longitudinal traction vehicle has been improved to a tray that can be adjusted laterally by 300mm, simplifying lateral adjustment, reducing labor intensity, and increasing work efficiency. The hydraulic system is safe and reliable, and the machine features a skid steering function, preventing derailment and allowing smooth passage through small-radius curves around turnouts. It is easy to install, quick and easy to remove from the track, and does not encroach on the clearance gauge after removal, ensuring safe train operation. It is an ideal and essential tool for mechanized maintenance of railway lines.

[0052] To ensure the safe and stable longitudinal movement of the turnout, a performance study was conducted on the lifting force of the turnout replacement unit's hoisting device and the load-bearing capacity of the longitudinal traction vehicle, and a reasonable allocation was made according to the length and cross-sectional weight of turnout No. 42. The main performance characteristics of the traction vehicle in this scheme are as follows: the single-cylinder lifting force of the hoisting device is 200KN (20T); a single longitudinal traction vehicle has a load-bearing capacity of ≥200kN (20T) and a maximum traction force of ≥60kN (6T).

[0053] In this embodiment, as Figures 2-3 As shown, the hydraulic cylinders of the lifting device are symmetrically arranged according to the turnout structure, with a total of 24 pairs. The lifting force of each pair of hydraulic cylinders is about 8-14T, and the lifting force of a single cylinder of the lifting device is 200KN (20T), which meets the lifting requirements of the turnout and ensures the safe and stable lifting and lowering of the turnout as a whole. Point P is the center position of the trolley, and point T is the installation point of the hydraulic cylinder.

[0054] The turnout longitudinal traction trolleys are arranged in a configuration of 21 units, including 9 powered traction trolleys and 12 driven traction trolleys. Each longitudinal traction trolley has a rated load capacity of 20 tons. The traction trolleys are deployed at intervals of 7-9 sleepers, with a load capacity of 10-13 tons per trolley to meet the load requirements of the trolley (the total weight of the turnout is 262 tons, including the weight of the switch machine). In this embodiment, the turnout weight is 262 tons, and the traction force of each powered longitudinal traction trolley is 60 kN. The forward rolling friction force = normal force * rolling friction coefficient (calculated based on a rolling friction coefficient of 0.1 for wheels and rails), so the rolling friction force F = utg = 0.1 * 262 * 9.8 kg / N = 257 kN. Calculations show that 5 powered longitudinal traction trolleys are sufficient to meet the construction requirements; however, 9 powered traction trolleys are deployed during construction. The turnout longitudinal tracing length is 420 meters. Based on experimental results, with 5 powered traction trolleys, the turnout longitudinal tracing speed can reach 10 m / min, resulting in high construction efficiency.

[0055] The lateral movement assembly consists of a roller bracket, seven sets of rollers, and a base plate, with dimensions of 2000 mm long, 255 mm wide, and 230 mm high. The roller bracket uses 120*120*4 square tubing as the crossbeam, 60*60*4 square tubing as the longitudinal beam, and 255*80*6 channel steel as the roller support. The roller assembly is composed of 95*10 seamless tubing, two 307 bearing discs, and 40 mm diameter round steel. The base plate is made of 2000*255*12 steel plate as the sliding plate. The static load capacity of a single roller assembly is ≤7 tons, and the dynamic load capacity is ≤4 tons. The static load capacity of a single roller bracket is ≤45 tons. For specific structural details, refer to patent number "202323564353.8," entitled "A Lateral Movement Device for Existing Line Switches."

[0056] Determining the optimal turnout moving track path includes the following steps:

[0057] a. Based on the location of the insertion position, mark out the turnout parking area after the turnout is moved longitudinally to the position, and at the same time plan the turnout moving track line from the direction of turnout movement. The turnout moving track line is divided into the inner line S1 located in the turnout parking area and the outer line S2 located outside the turnout parking area.

[0058] b. Simulate the movement of the turnout into place: Simulate the existing ballasted track, the ballasted track to be connected, the turnout parking area, the turnout moving track route, and the turnout moved into place. The lateral movement distance from the turnout head to the existing ballasted track is A1, and the lateral movement distance from the turnout tail of the straight track to the existing ballasted track is A2, where A2≥A1.

[0059] c. Determine the optimal turnout moving track path: If the deviation between A1 and A2 does not exceed 50mm, then retain the existing inner line S1. The optimal turnout moving track path is the inner line S1 and the outer line S2. If the deviation between A1 and A2 is greater than 50mm, adjust the inner line S1 until A1 and A2 are equal. The adjusted inner line is the inner line S3. After determining the inner line S3, adjust the outer line S2 to connect smoothly with the inner line S3. The adjusted outer line is the outer line S4. At this time, the optimal turnout moving track path is the inner line S3 and the outer line S4.

[0060] like Figure 4 As shown, the intersection point of the turnout moving track and the turnout parking area is M0. Then, using the end face of the straight strand of the turnout as the reference plane, the center of the reference plane is selected as the reference point for rotation until A1 and A2 are equal. A circle is drawn with the reference point as the passing point and the internal track curvature radius R, where R ≥ 2500m, to obtain the intersection point M1 with the turnout parking area (adjusted from M0 to M1). At this point, the turnout moving track path is optimized. The red indicator shows the rotated turnout and track. In this embodiment, as... Figure 5 As shown, due to site limitations, existing equipment (signals, overhead contact lines, rigid cross spans, existing turnout switch machines, transformer boxes, etc.) causes significant interference. During turnout assembly, the turnout center cannot coincide with the center of the connecting line, with a deviation of 0.9m. This results in uneven loading during assembly, causing the designed track to be laid out unevenly, and the turnout's straight main rail to be straight. Later, during the overall longitudinal movement of the turnout, the longitudinal movement trolley can be placed on the unevenly laid connecting line to align the turnout sleeper center with the longitudinal movement trolley center, achieving the conditions for overall turnout longitudinal movement. The coordinates of the unevenly laid track center are collected and imported into CAD drawing software to simulate the turnout's shape when it is positioned above the connecting line. The center line of the turnout's straight track is determined, and the 5m points of the straight track are laid out and marked on-site. The adjusted distance of the turnout tail beam is significantly reduced after correction. The red line represents the upstream connecting line, the blue line represents the simulated line, and the green line represents the adjusted line.

[0061] The term "moving to position" refers to moving the turnout head to align with the existing ballast track turnout connection point.

[0062] like Figures 6-8As shown, the fine-tuning device consists of multiple evenly distributed caster wheel assemblies. Each caster wheel assembly includes a lower pad 1 and an upper pad 2. A base 3 is mounted on the lower pad 1, and the base 3 has multiple mounting slots 4 arranged around its center, with a minimum of three slots. A rotating ball 5 is movably mounted in each mounting slot 4. The rotating balls 5 are at the same elevation and protrude from the base 3. Each mounting slot 4 has multiple limiting blocks 6 for restricting the rotating balls 5, with the inner side of each limiting block 6 being an arc surface. During turnout attitude adjustment, the lower surface of the upper pad 2 is in close contact with all the rotating balls 5 on the base 3, and the turnout is placed on the upper surface of the upper pad 2. Among them, the rotating sphere 5 is an iron ball with a diameter of 80mm; the base 3 is a triangular iron plate with a side length of 346.41mm; the lower pad 1 and the upper pad 2 are the same size, with dimensions of 400mm*400mm*10mm.

[0063] This solution enables the completion of existing track dismantling, seamless turnout insertion, manual track maintenance, welding, and fine-tuning within 460 minutes of a single track maintenance window, followed by speed-limited operation. This significantly improves the efficiency of inserting large-number turnouts in confined spaces. Furthermore, simulation optimization of the turnout moving track was conducted, employing a whole-track moving method with attitude adjustments via lateral movement and fine-tuning devices. This overcomes the limitations of existing insertion conditions, improving turnout assembly accuracy and efficiency, and overall transportation safety. Turnout No. 42 was precisely inserted in one go, reducing construction and maintenance investment, saving manpower, materials, and time, and lowering costs by 3.48 million yuan. Simultaneously, the addition of soft and hard isolation measures reduces the impact of construction blockades on railway transportation, adding value to railway transport and avoiding multiple train cancellations, resulting in significant economic benefits. It also reduces the scope of construction impact and minimizes interference with operating lines. Moreover, the application of this solution has positive implications for saving project costs and improving the safety management level of operating lines, effectively promoting the development of mechanized construction technology for inserting large turnouts into existing tracks.

[0064] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A method for installing turnouts on existing ballasted tracks, characterized in that, Includes the following steps: S1. Determine the track path for the turnout: Based on the placement position and the direction of turnout movement, determine the optimal track path for the turnout. Determining the optimal turnout moving track path includes the following steps: a. Based on the location of the insertion position, mark out the turnout parking area after the turnout is moved longitudinally to the position, and at the same time plan the turnout moving track line from the direction of turnout movement. The turnout moving track line is divided into the inner line S1 located in the turnout parking area and the outer line S2 located outside the turnout parking area. b. Simulate the movement of the turnout into place: Simulate the existing ballasted track, the ballasted track to be connected, the turnout parking area, the turnout moving track route, and the turnout moved into place. The lateral movement distance from the turnout head to the existing ballasted track is A1, and the lateral movement distance from the turnout tail of the straight track to the existing ballasted track is A2, where A2≥A1. c. Determine the optimal turnout moving track path: If the deviation between A1 and A2 does not exceed 50mm, then retain the existing inner line S1. The optimal turnout moving track path is the inner line S1 and the outer line S2. If the deviation between A1 and A2 is greater than 50mm, adjust the inner line S1 until A1 and A2 are equal. The adjusted inner line is the inner line S3. After determining the inner line S3, adjust the outer line S2 to connect with the inner line S3. The adjusted outer line is the outer line S4. At this time, the optimal turnout moving track path is the inner line S3 and the outer line S4. S2. Pre-construction preparation: Utilize the daylight window before the insertion point to complete the installation of hard barriers and mark the points at the insertion location, and at the same time lay the running rail according to the optimal turnout moving track path; S3. Removal of existing ballasted track: During the track maintenance window, the existing ballasted track is sawn according to the location of the insertion, and the sawn rails and sleepers in the section where the insertion is located are removed and the track bed is inspected. S4. Moving turnout: Using the laid track, the assembled turnout is moved to the insertion position by a tractor. S5. Lifting the turnout: After the turnout is moved into place, the turnout is lifted by the lifting cylinder group installed on the tractor. Then, a safety block is set up under the turnout, and the tractor and the traveling rail under the turnout are removed. S6. Lowering the turnout: A lateral movement device and a movable lifting cylinder group are arranged below the turnout. The turnout is lifted by the movable lifting cylinder group, removed from the safety block, and lowered onto the lateral movement device. The movable lifting cylinder group is then removed. S7. Turnout attitude adjustment: The turnout is adjusted laterally in a large direction using the lateral movement device until the lateral movement distance is less than 2cm. The movable lifting cylinder group is placed under the turnout, and the turnout is lifted by the movable lifting cylinder group. The lateral movement device is then removed. The fine adjustment device is then installed under the turnout, and the turnout is placed on the fine adjustment device. The movable lifting cylinder group is removed, and the turnout is adjusted by the fine adjustment device until the lateral movement distance is less than 5mm, thus completing the turnout attitude adjustment. S8. Turnout entry: Install a movable lifting cylinder group under the turnout. Lift the turnout by the movable lifting cylinder group and remove the fine adjustment device. Then, use the movable lifting cylinder to control the rail surface elevation of the turnout. Connect the joint with a clamp plate to complete the turnout entry. S9. Backfilling ballast: After the turnout is completed, backfill the ballast at the insertion position and tamp and cure it, leaving a weld seam. Remove the movable lifting cylinder during the backfilling process. S10. Turnout welding: After the tamping and curing meet the standards, welding operations are carried out on the turnouts and the existing ballasted lines and the ballasted lines to be connected. S11. Final Adjustment of the Track: After the welding is qualified, the direction and elevation of the track are adjusted by a track shifting machine until the design requirements are met, and the laying operation is completed.

2. The method for installing turnouts on existing ballasted tracks according to claim 1, characterized in that, The outer track S2 includes one or a combination of straight track and curved track.

3. The method for installing turnouts on existing ballasted tracks according to claim 1, characterized in that, The term "moving to position" refers to moving the turnout head to align with the existing ballast track turnout connection point.

4. The method for installing turnouts on existing ballasted tracks according to claim 1, characterized in that, The fine-tuning device consists of multiple evenly distributed caster wheel assemblies.

5. The method for installing turnouts on existing ballasted tracks according to claim 4, characterized in that, The universal wheel assembly includes a lower pad (1) and an upper pad (2). A base (3) is provided on the lower pad (1). A plurality of mounting grooves (4) are provided on the base (3) surrounding the center of the base (3). The number of mounting grooves (4) is not less than 3. A rotating ball (5) is movably installed in each mounting groove (4). The rotating balls (5) have the same elevation and protrude from the base (3). A plurality of limiting blocks (6) for limiting the rotating balls (5) are provided on each mounting groove (4). When the turnout attitude is adjusted, the lower surface of the upper pad (2) is in close contact with all the rotating balls (5) on the base (3), and the turnout is placed on the upper surface of the upper pad (2).

6. The method for installing turnouts on existing ballasted tracks according to claim 1, characterized in that, The rail surface elevation control mentioned in step S8 refers to the control of the turnout rail surface elevation based on the existing ballast track rail surface elevation with a 20mm allowance, and the slope from the turnout head and tail towards the turnout inside at 1‰, with the curved track side controlled at 0.5mm lower than the straight track side.

7. The method for installing turnouts on existing ballasted tracks according to claim 1, characterized in that, In step S9, ballast is first backfilled at the point of the movable lifting cylinder below the turnout. The backfilling process is carried out in sections, and the turnout is adjusted in elevation and orientation during the section backfilling.

8. The method for installing turnouts on existing ballasted tracks according to claim 1, characterized in that, In step S10, the turnout is first welded to the existing ballasted track, and then the turnout is welded to the ballasted track to be connected the next day.

9. A method for installing turnouts on existing ballasted tracks according to claim 1 or 6, characterized in that, In step S8, a 5-8mm weld seam is left at the joint.

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