Construction method for rapid fixing and precision adjustment of busbar in power transformation and distribution project

Abstract

The application relates to the technical field of bus installation and construction of power transformation and distribution engineering, and discloses a bus rapid fixing and precision adjusting construction method of power transformation and distribution engineering, which comprises the following steps: 1, construction preparation and positioning and line laying; 2, support system rapid installation; 3, bus rapid positioning and initial fixing; 4, accurate connection and precision adjustment; and 5, inspection and system verification. The bus rapid fixing and precision adjusting construction method of power transformation and distribution engineering improves the initial fixing speed. The hydraulic lifting platform, the laser collimation target and the quick clamping tool with the scaled sliding seat are used in cooperation, so that the operator can quantitatively lock the horizontal and straightness deviation immediately after the bus is positioned, the traditional manual prying and repeated pad process is replaced, the positioning and initial adjustment time of a single bus is shortened from about 40 minutes to about 15 minutes, and the operation risk of repeatedly tightening and loosening the high-altitude bolts is reduced.

Description

Technical Field

[0001] This invention relates to the field of busbar installation and construction technology in power distribution engineering, specifically to a method for rapid fixing and precision adjustment of busbars in power distribution engineering. Background Technology

[0002] In power distribution projects of large commercial complexes, data centers, and industrial plants, high-density busbar trunking serves as a high-current main transmission channel. It typically needs to be laid horizontally along the walls or columns of the distribution room, with a single straight section reaching tens or even hundreds of meters in length, constructed from multiple standard sections connected in series. The straightness, horizontality, and expansion / contraction compensation gaps of the busbar installation directly affect the stability of the joint contact resistance and the structural safety under thermal expansion and contraction conditions, making them key aspects of construction quality control.

[0003] The commonly used method for fixing and adjusting busbars on-site involves first installing fixed supports on the concrete structure using post-installed anchor bolts, then hoisting each section of the busbar into position one by one. Workers use a steel wire or level pipe as a straightening benchmark, visually assessing deviations and then filling the bottom and sides of the busbar with galvanized iron sheets or epoxy pads to achieve leveling. This process has a common problem: once the supports are anchored to the structure, their spatial position is locked, making it difficult to provide quantifiable fine-tuning freedom. When the busbar section is positioned and the levelness or straightness is found to be out of tolerance, the only solution is to repeatedly loosen the support bolts, add or remove shims, and pry the trough to correct it. A single section adjustment often requires tightening and loosening the bolts three to four times. Especially in straight sections exceeding 80 meters in length, the steel wire sags by 2mm to 4mm in the middle due to its own weight. This causes the busbar adjusted to this benchmark to appear visually straight, but laser verification often reveals an actual straightness deviation exceeding 6mm along its entire length, forcing the construction team to rework. Meanwhile, the clearance setting within the busbar expansion joint compensation device has long relied on operators' manual feeler gauges or visual estimation, lacking a step for quantitative calculation based on the difference between ambient temperature and design temperature. This often leads to potential problems such as busbar expansion causing jamming in summer and contraction and cracking at connections in winter. For example, in a data center power distribution room project, a 120-meter-long 2500A busbar trunking was constructed using the aforementioned traditional method. Seven workers spent four working days completing the fine-tuning, and the worst deviation in straightness measured during acceptance was still 7mm. After only one summer of operation, one compensator experienced copper busbar bending due to insufficient clearance, forcing a power outage for replacement. This phenomenon indicates that existing technology lacks a systematic construction method that integrates temporary support, displacement fine-tuning, precision measurement, and rapid locking functions, and can accurately set the expansion clearance based on environmental parameters. This results in low fixing and adjustment efficiency, unstable precision control, and potential quality risks for long-term busbar operation. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a construction method for rapid fixing and precision adjustment of busbars in power distribution engineering. It has advantages such as reducing the operational risks of repeatedly tightening and loosening bolts at high altitudes, and solves the problems of low fixing and adjustment efficiency and unstable precision control.

[0005] To achieve the above objectives and reduce the operational risks associated with repeatedly tightening and loosening bolts at heights, this invention provides the following technical solution: a construction method for rapid fixing and precision adjustment of busbars in power distribution engineering, comprising: step 1 construction preparation and positioning layout; step 2 rapid installation of the support system; step 3 rapid positioning and initial fixing of the busbars; step 4 precise connection and precision adjustment; and step 5 inspection and system verification. Step 1 construction preparation and positioning layout includes: step 101 site condition verification and path planning; step 102 elevation and vertical transfer; and step 103 material and tooling placement. Among them, the rapid installation of the support system in step 2 includes step 201 base anchoring and initial leveling, step 202 adjustable column and crossarm pre-assembly, and step 203 rapid assembly of insulating pad and limiting component. Step 3, rapid positioning and initial fixing of the busbar, includes step 301, segmented hoisting and docking positioning, step 302, rapid clamping tooling intervention, and step 303, rapid fixing of vertical sections and bends. Among them, step 4, precise connection and precision adjustment, includes step 401, conductor lap surface treatment and bolt tightening, step 402, fine adjustment of overall straightness and perpendicularity, and step 403, adjustment of expansion compensation device and grounding bridging. Step 5, Inspection and System Verification, includes Step 501, Insulation Testing and Circuit Verification; Step 502, Point-by-Point Re-inspection of Fasteners and Anti-Loosening Measures; and Step 503, Cleaning and Handover of As-Completed Status.

[0006] Preferably, step 101 involves on-site condition verification and route planning: Verify the handover documents for the power distribution room civil engineering, focusing on confirming whether the location of reserved holes, the elevation of embedded parts, the flatness of the ground, and the verticality of the walls meet the construction requirements. Use a laser rangefinder to scan along the design path of the busbar, mark the locations where it may intersect with other pipelines and equipment, and form a path conflict list. Based on the busbar phase sequence and branch interface locations on the design drawings, mark the center line of the busbar and the cross lines for the bracket positioning on the ground. The deviation of the center line should be controlled within ±2mm. For long straight sections of the busbar, mark the installation location of the compensator in advance on the path line according to the principle of setting an expansion compensation unit every 9m. Step 102: Elevation and Vertical Transfer Based on the elevation benchmark provided by the civil engineering in the power distribution room, a level instrument is used to transfer the +1.0m elevation line to all busbar installation walls and columns, and a continuous horizontal line is marked with a chalk line. For multi-layer busbar installation areas, according to the common parameters of 250mm between phase centers and 150mm between phase conductor centers, the bottom elevation line of each layer of busbar is marked layer by layer. For the vertical section of the busbar path, a plumb line combined with a theodolite is used to transfer the vertical line from top to bottom in the shaft. A vertical benchmark point is marked on the wall every 1.8m, and the verticality deviation between two points is no more than 1.5mm. Step 103: Materials and tooling in place: Inventory the incoming high-density busbar trunking and accessories, verify the section number, rated current level (e.g., 2000A / 2500A), and protection level markings, check for any bumps or damage to the insulation boards, and ensure the silver plating on the conductor lap surfaces is intact. Prepare specialized tooling, including an adjustable busbar positioning bracket, a hydraulic lifting platform, a laser collimator emitter set, a torque wrench (calibrated and with a range covering 70-100 N·m), non-metallic impact pads, a phase-to-phase insulation resistance tester, and a quick-clamping and adjustment tooling consisting of a channel steel base, a graduated sliding seat, and a horizontal fine-tuning screw.

[0007] Preferably, step 201 involves anchoring and initial leveling of the base: At the pop-up crosshair positioning point, install hot-dip galvanized channel steel bases. Use rear-expanded bottom anchor bolts to fix the bases to the concrete structure, with an anchoring depth of not less than 80mm. Use 4 anchor bolts diagonally to fasten each base. After the bases are installed, use a level to measure the elevation of their upper plane. By inserting stainless steel adjusting shims at the bottom, control the deviation between the elevation of each base and the design elevation to be within 0 to -1mm. The center distance between adjacent bases on straight sections is set at 1.5m. Add reinforcing supports at bends, branches, and ends, with a center distance not exceeding 0.5m.

[0008] Preferably, step 202 involves the pre-installation of the adjustable column and crossbeam: Embed the C-shaped steel column into the socket of the base. The column has elongated holes on all four sides. The vertical adjustment stroke is ±30mm. Do not lock the connecting bolts first. Insert the crossbeam and adjust it to be horizontal with a magnetic level. When inserting the crossbeam into the column, insert it into the corresponding hole according to the elevation of the generatrix of each layer. Initially tighten the anti-loosening nut. Use a straightedge to check the vertical flatness of the left and right columns of the same section. Adjust the translation position of the column in the base so that the sides of the entire column are on the same elevation, with the deviation controlled within 1mm / m. Then use an electric wrench to tighten the clamping bolts between the column and the base with a torque of 40N·m to form a rigid portal frame.

[0009] Preferably, step 203 involves the rapid assembly of the insulating pad and the limiting member: Insert the SMC insulation pads into the pre-set T-slots on the crossarm. The spacing between the pads should be controlled according to the busbar width + 1.5mm. After the pads are placed, insert the nylon phase-separating blocks. The blocks have elastic buckles that can be pressed down to fix them. Install detachable lateral limiting angle steel at the end of the crossarm. The vertical surface of the angle steel is covered with 3mm thick epoxy fiberglass cloth to form the lateral constraint boundary of the busbar. The entire support section is now assembled. Check that all insulation components are free from skewing or looseness.

[0010] Preferably, step 301 involves segmented hoisting and docking in place: Using a hydraulic lifting platform, a section of busbar unit is lifted to a position approximately 20mm above the designated elevation. It is then slowly advanced between the two supports. The operator holds a laser collimator and attaches it to the side of the conductor of the installed busbar section. The beam is projected onto a target on the side of the conductor of the section to be positioned. The operator directs the lifting platform to make minor adjustments until the beam aligns with the center line of the target. After confirming alignment, the lifting platform slowly descends, allowing the busbar body to rest smoothly on the insulating pad. At this point, the limiting angle steel naturally restricts its left and right sway. The guide positioning pin at the connector is inserted to initially tighten the two busbar sections, but not lock them in place.

[0011] Preferably, in step 302, the quick clamping fixture is engaged: Insert the sliding seat of the quick-clamping adjustment fixture into the lower flange of the support channel steel. The end of the lateral fine-tuning screw of the fixture abuts against the side plate of the busbar. Configure one fixture every 3m for the straight section. First, tighten the longitudinal tensioning component with a wrench to eliminate the gap between sections. Make the compression of the insulating partition at the joint reach 0.2-0.3mm and visually fit. Then, alternately adjust the left and right lateral fine-tuning screws. According to the laser target reading, adjust the horizontal straightness deviation of the busbar to within 1.5mm / 10m. After completion, lock all the wing nuts on the fixture to form a temporary rigid fixation. Step 303: Quickly fix the vertical section and bend: Inside the vertical busbar shaft, pre-installed load-bearing supports are used as the lower support points. The upper part is hoisted with ropes to hang the bend and vertical section. A clamp-type sliding support is installed in the middle of the vertical section. The clamp is lined with a silicone rubber buffer pad, and the tightening torque is controlled at 15 N·m. This prevents the busbar from sliding under its own weight and also leaves axial sliding margin for thermal expansion and contraction. Anti-vibration supports are added 1m on each side of the bend. The supports are pressed against the busbar with U-shaped pressure plates and butterfly-shaped spring pads to prevent micro-displacement caused by electromagnetic forces during operation.

[0012] Preferably, step 401 involves the treatment of the conductor lap joint surface and bolt tightening: Remove the connector cover plate and wipe the conductor lap surface with anhydrous alcohol. If there are slight oxidation spots, use fine sandpaper of 400 grit or higher to polish and clean along the length of the busbar. Insert the 8.8 grade galvanized fastening bolts and apply torque in three stages in a diagonal sequence: first, pre-tighten to 30% of the target torque; second, to 60%; and third, tighten to the design torque value using a calibrated torque wrench. Common torque parameters for copper busbar lap connections are: 70 N·m for M12 bolts and 90 N·m for M16 bolts. After tightening, use a 0.02 mm feeler gauge to check the lap surface around the perimeter. The insertion depth should not exceed 10% of the lap surface width. Step 402: Fine-tuning of overall straightness and perpendicularity: Remove some of the temporary clamping fixtures, leaving only the fixtures at the beginning and end. Use a laser collimator to scan along the entire length, and provide feedback on the straightness deviation in segments. For local points that exceed the standard, loosen the connecting bolts between the crossarm and the column of that section of the support, and insert U-shaped adjusting shims of 0.5mm, 1mm, and 2mm thickness to change the pitch angle and horizontal displacement of the crossarm until the beam offset falls back to within 2mm / length. For the vertical section, adjust the verticality through the turnbuckles at the top of the shaft. Under the monitoring of the theodolite, correct the tilt to no more than 1‰. After correction, re-tighten all support connectors. Step 403: Adjustment of the expansion joint compensation device and grounding bridging: At the busbar compensator installation location, loosen the temporary spacing plates at both ends of the compensator, measure the gap between the busbar ends on both sides of the compensator, and adjust the gap to the calculated value by using the guide rod nuts inside the compensator, based on the difference between the ambient temperature and the design temperature and referring to the empirical value of reserving a gap of 1.5mm for every 10℃ temperature difference. The allowable deviation is ±0.5mm. At the same time, install the braided copper strip grounding jumper, with a cross-sectional area of ​​not less than half of the phase conductor cross-sectional area. Clean the crimping surfaces on both sides with a copper brush, and tighten the bolts to the same torque as the phase conductor. The grounding jumper at the compensator should have a 40mm expansion bend to accommodate the thermal displacement of the busbar.

[0013] Preferably, step 501 involves insulation testing and circuit verification: After all fine-tuning is completed, remove all temporary fixtures and jumper clamps. Use a 2500V megohmmeter to measure the insulation resistance between each phase conductor and between the phase conductor and the outer casing. The test value must not be less than 50MΩ. For busbar systems with a length of more than 100m, calculate the total insulation resistance after segmented testing to confirm that there are no missing grounding points. Then, use a phase sequence table to verify that the phase sequence of each segment and branch circuit is consistent with the system design drawing. Double confirmation is made at the end and intermediate branch boxes, and the connection of the N line and PE line conductors is checked simultaneously. Step 502: Re-inspect fasteners and anti-loosening measures point by point: Working in pairs, one person uses a torque wrench to check the torque of all connecting bolts, while the other records and applies paint to confirm. The check proceeds from the power inlet to the load end, focusing on checking each bolt at the connector, branch plug-in box interface, compensation device, and grounding jumper. In areas with vibration, self-locking inserts are added to the nut ends or thread-locking agent is applied to prevent loosening during long-term operation. All paint marks are covered with different colored paint to facilitate inspection and traceability.

[0014] Preferably, step 503 involves cleaning and handing over the completed project: Clean the inside of the busbar trunking, joints, and surrounding area of ​​metal debris, tools, and foreign objects. Blow dry compressed air onto the surfaces of conductors and insulators. Restore all end caps, joint covers, and protective baffles. Confirm that the IP protection level sealing strips are not warped. Compile construction records, including insulation resistance test values, torque re-verification lists, expansion gap adjustment records, and measurement and layout deviation charts, and submit them along with the as-built documentation. Finally, remove the construction area fencing, clear tools and remaining materials out of the power distribution room, and complete the site restoration.

[0015] Compared with existing technologies, this invention provides a construction method for rapid fixing and precision adjustment of busbars in power distribution engineering, which has the following beneficial effects: 1. The construction method for rapid fixing and precision adjustment of busbars in this power distribution project improves the initial fixing speed. By using a hydraulic lifting platform, a laser collimation target, and a rapid clamping fixture with a graduated sliding seat in tandem, operators can immediately quantify and lock the horizontal and straightness deviations after the busbar is in place. This replaces the traditional manual prying and repeated padding process. The time for positioning and initial adjustment of a single busbar section is reduced from about 40 minutes to about 15 minutes, and the risk of repeated tightening and loosening of bolts at high altitudes is also reduced.

[0016] 2. The construction method for rapid fixing and precision adjustment of busbars in this power distribution project allows for controllable and reversible precision adjustment along the entire length. In the fine-tuning stage, adjustable columns and U-shaped adjustment shims are used in conjunction with laser full-length scanning to continuously fine-tune the pitch and horizontal displacement of the supports. Without the need for gas cutting or welding, the straightness deviation along the entire length can be stably controlled within 2mm, avoiding thermal deformation and damage to the anchoring structure caused by hot work, while also ensuring that the busbar runs close to the designed path.

[0017] 3. The construction method for rapid fixing and precision adjustment of busbars in this power distribution project quantifies and determines the expansion compensation gap. In the adjustment of the expansion compensation device, a linear conversion relationship between ambient temperature and design temperature difference is introduced. The gap value is precisely set to the calculated requirement value through the guide rod nut built into the compensator, eliminating the improper reservation caused by manual experience estimation and helping to reduce the additional stress on the joints and structural deformation caused by thermal expansion and contraction.

[0018] 4. The construction method for rapid fixing and precision adjustment of busbars in this power distribution project allows for the reuse of tooling. The rapid clamping and adjustment tooling adopts a modular clamping structure, which can be removed and reused in the next work section after fine adjustment. This does not damage the busbar shell and insulation layer, and reduces the consumption of temporary support materials and the generation of waste. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] This solution provides a technical approach for the rapid fixing and precision adjustment of busbars in power distribution engineering, including the following steps: Step 1: Construction preparation and positioning layout: Step 101: On-site condition verification and route planning: Verify the handover documents for the power distribution room civil engineering, focusing on confirming whether the location of reserved holes, the elevation of embedded parts, the flatness of the ground, and the verticality of the walls meet the construction requirements. Use a laser rangefinder to scan along the design path of the busbar, mark the locations where it may intersect with other pipelines and equipment, and form a path conflict list. Based on the busbar phase sequence and branch interface locations on the design drawings, mark the center line of the busbar and the cross lines for the bracket positioning on the ground. The deviation of the center line should be controlled within ±2mm. For long straight sections of the busbar, mark the installation location of the compensator in advance on the path line according to the principle of setting an expansion compensation unit every 9m. Step 102: Elevation and Vertical Transfer Based on the elevation benchmark provided by the civil engineering in the power distribution room, a level instrument is used to transfer the +1.0m elevation line to all busbar installation walls and columns, and a continuous horizontal line is marked with a chalk line. For multi-layer busbar installation areas, according to the common parameters of 250mm between phase centers and 150mm between phase conductor centers, the bottom elevation line of each layer of busbar is marked layer by layer. For the vertical section of the busbar path, a plumb line combined with a theodolite is used to transfer the vertical line from top to bottom in the shaft. A vertical benchmark point is marked on the wall every 1.8m, and the verticality deviation between two points is no more than 1.5mm. Step 103: Materials and tooling in place: Inventory the incoming high-density busbar trunking and accessories, verify the section number, rated current level (e.g., 2000A / 2500A), and protection level markings, check for any bumps or damage to the insulation boards, and ensure the silver plating on the conductor lap surfaces is intact. Prepare specialized tooling, including adjustable busbar positioning brackets, hydraulic lifting platforms, laser collimator emitter sets, torque wrenches (calibrated and qualified, with a range covering 70-100 N·m), non-metallic impact pads, phase-to-phase insulation resistance testers, and a set of quick-clamping and adjustment tooling consisting of a channel steel base, a graduated sliding seat, and a horizontal fine-tuning screw. Step 2: Quick installation of the bracket system: Step 201: Base anchoring and initial leveling: At the pop-up crosshair positioning point, install hot-dip galvanized channel steel bases. Use rear-expanded bottom anchor bolts to fix the bases to the concrete structure, with an anchoring depth of not less than 80mm. Use 4 anchor bolts diagonally to fix a single base. After the bases are installed, use a level to measure the elevation of the upper plane. By inserting stainless steel adjusting shims at the bottom, the elevation of each base is controlled to be within 0 to -1mm of the design elevation. The center distance between adjacent bases on straight sections is set at 1.5m. Add reinforcing supports at bends, branches and ends, with a center distance of not more than 0.5m. Step 202: Pre-installation of adjustable columns and crossarms: Embed the C-shaped steel column into the socket of the base. The column has elongated holes on all four sides. The vertical adjustment stroke is ±30mm. Do not lock the connecting bolts first. Insert the crossbeam and adjust it to be horizontal with a magnetic level. When inserting the crossbeam into the column, insert it into the corresponding hole according to the elevation of the generatrix of each layer. Initially tighten the anti-loosening nut. Use a straightedge to check the flatness of the vertical surface of the left and right columns of the same section. Adjust the translation position of the column in the base so that the side of the entire column is on the same elevation, and control the deviation within 1mm / m. Then use an electric wrench to tighten the clamping bolts between the column and the base with a torque of 40N·m to form a rigid portal frame. Step 203: Quick assembly of insulating pad and limiting component: Insert the SMC insulation pads into the pre-set T-slots on the crossarm. The spacing between the pads should be controlled according to the busbar width + 1.5mm. After the pads are placed, insert the nylon phase-separating blocks. The blocks have elastic buckles that can be pressed down to fix them. Install detachable lateral limiting angle steel at the end of the crossarm. The vertical surface of the angle steel is covered with 3mm thick epoxy glass cloth to form the lateral constraint boundary of the busbar. The entire support section is now assembled. Check that all insulation components are free from skewing or looseness. Step 3: Quick placement and initial fixing of the busbars: Step 301: Segmented hoisting and docking in place: Using a hydraulic lifting platform, lift a section of busbar unit to a position slightly above the designated elevation (about 20mm). Slowly advance it between the two supports. The operator holds a laser collimator and attaches it to the side of the conductor of the installed busbar section. The beam is projected onto the target on the side of the conductor of the section to be positioned. The operator directs the lifting platform to make minor adjustments until the beam coincides with the center line of the target. After confirming alignment, the lifting platform slowly lowers, allowing the busbar body to fall smoothly onto the insulating pad. At this point, the limiting angle steel naturally restricts its left and right sway. Insert the guide positioning pin at the connector to initially tighten the two busbar sections, but do not lock them. Step 302: Quick clamping fixture intervention: Insert the sliding seat of the quick-clamping adjustment fixture into the lower flange of the support channel steel. The end of the lateral fine-tuning screw of the fixture abuts against the side plate of the busbar. Configure one fixture every 3m for the straight section. First, tighten the longitudinal tensioning component with a wrench to eliminate the gap between sections. Make the compression of the insulating partition at the joint reach 0.2-0.3mm and visually fit. Then, alternately adjust the left and right lateral fine-tuning screws. According to the laser target reading, adjust the horizontal straightness deviation of the busbar to within 1.5mm / 10m. After completion, lock all the wing nuts on the fixture to form a temporary rigid fixation. Step 303: Quickly fix the vertical section and bend: Inside the vertical busbar shaft, a pre-installed load-bearing bracket is used as the lower support point. The upper part is hoisted with ropes to hang the elbow and vertical section. A clamp-type sliding support is installed in the middle of the vertical section. The clamp is lined with a silicone rubber buffer pad. The tightening torque is controlled at 15 N·m. This prevents the busbar from sliding under its own weight and leaves axial sliding margin for thermal expansion and contraction. Anti-vibration brackets are added 1m on each side of the elbow. The brackets and the busbar are pressed together with U-shaped pressure plates and butterfly-shaped spring pads to prevent micro-displacement caused by electromagnetic force during operation. Step 4: Precise Connection and Accuracy Adjustment Step 401: Conductor lap joint treatment and bolt tightening: Remove the connector cover plate and wipe the conductor lap surface with anhydrous alcohol. If there are slight oxidation spots, use fine sandpaper of 400 grit or higher to polish and clean along the length of the busbar. Insert the 8.8 grade galvanized fastening bolts and apply torque in three stages in a diagonal sequence: first, pre-tighten to 30% of the target torque; second, to 60%; and third, tighten to the design torque value using a calibrated torque wrench. Common torque parameters for copper busbar lap connections are: 70 N·m for M12 bolts and 90 N·m for M16 bolts. After tightening, use a 0.02 mm feeler gauge to check the lap surface around the perimeter. The insertion depth should not exceed 10% of the lap surface width. Step 402: Fine-tuning of overall straightness and perpendicularity: Remove some of the temporary clamping fixtures, leaving only the fixtures at the beginning and end. Use a laser collimator to scan along the entire length, and provide feedback on the straightness deviation in segments. For local points that exceed the standard, loosen the connecting bolts between the crossarm and the column of that section of the support, and insert U-shaped adjusting shims of 0.5mm, 1mm, and 2mm thickness to change the pitch angle and horizontal displacement of the crossarm until the beam offset falls back to within 2mm / length. For the vertical section, adjust the verticality through the turnbuckles at the top of the shaft. Under the monitoring of the theodolite, correct the tilt to no more than 1‰. After correction, re-tighten all support connectors. Step 403: Adjustment of the expansion joint compensation device and grounding bridging: At the busbar compensator installation location, loosen the temporary spacing plates at both ends of the compensator, measure the gap between the busbar ends on both sides of the compensator, and adjust the gap to the calculated value by using the guide rod nuts inside the compensator, based on the difference between the ambient temperature and the design temperature and referring to the empirical value of reserving a gap of 1.5mm for every 10℃ temperature difference. The allowable deviation is ±0.5mm. At the same time, install the braided copper strip grounding jumper, with a cross-sectional area of ​​not less than half of the phase conductor cross-sectional area. Clean the crimping surfaces on both sides with a copper brush, and tighten the bolts to the same torque as the phase conductor. The grounding jumper at the compensator should have a 40mm expansion bend to accommodate the thermal displacement of the busbar. Step 5: Inspection and System Verification Step 501 Insulation Test and Circuit Verification: After all fine-tuning is completed, remove all temporary fixtures and jumper clamps. Use a 2500V megohmmeter to measure the insulation resistance between each phase conductor and between the phase conductor and the outer casing. The test value must not be less than 50MΩ. For busbar systems with a length of more than 100m, calculate the total insulation resistance after segmented testing to confirm that there are no missing grounding points. Then, use a phase sequence table to verify that the phase sequence of each segment and branch circuit is consistent with the system design drawing. Double confirmation is made at the end and intermediate branch boxes, and the connection of the N line and PE line conductors is checked simultaneously. Step 502: Re-inspect fasteners and anti-loosening measures point by point: Two people work together. One person holds a torque wrench to check the torque of all connecting bolts, while the other person records and confirms the torque with paint. The check sequence proceeds from the power inlet to the load end. The focus is on checking each bolt at the connector, branch plug box interface, compensation device and grounding jumper. In areas with vibration, self-locking inserts are added to the end of the nut or thread-locking agent is applied to prevent loosening during long-term operation. All paint marks are covered with different colored paint to facilitate inspection and traceability. Step 503 Cleaning and Handover of Completed Status: Clean up metal debris, tools, and foreign objects inside the busbar trunking, joints, and surrounding area. Blow dry compressed air to clean the surfaces of conductors and insulators. Restore all end caps, joint covers, and protective baffles. Confirm that the IP protection level sealing strips are not warped. Organize construction records, including insulation resistance test values, torque re-verification list, expansion gap adjustment records, and measurement and layout deviation charts, and submit them along with the as-built documentation. Finally, remove the construction area fences, clear tools and remaining materials out of the power distribution room, and complete the site restoration. Furthermore, the initial fixing speed has been improved. By using a hydraulic lifting platform, a laser collimation target, and a quick clamping fixture with a graduated sliding seat in tandem, operators can immediately quantify and lock the horizontal and straightness deviations after the busbar is in place, replacing the traditional manual prying and repeated padding process. The time for positioning and initial adjustment of a single busbar section has been reduced from about 40 minutes to about 15 minutes, and the risk of repeatedly loosening and tightening bolts at high altitudes has been reduced. Furthermore, the full-length precision adjustment is controllable and reversible. In the fine-tuning stage, adjustable columns and U-shaped series adjustment shims are used in conjunction with laser full-length scanning to continuously fine-tune the pitch and horizontal displacement of the support. Without the need for gas cutting or welding, the full-length straightness deviation can be stably controlled within 2mm, avoiding thermal deformation and anchoring structure damage caused by hot work, while also ensuring that the busbar runs close to the design path. Furthermore, the expansion and contraction gap is quantitatively determined. In the adjustment of the expansion and contraction compensation device, a linear conversion relationship between the ambient temperature and the design temperature difference is introduced. The gap value is precisely set to the calculated requirement value through the guide rod nut built into the compensator, eliminating the improper reservation caused by manual experience estimation, which helps to reduce the additional stress on the joint and structural deformation caused by thermal expansion and contraction. Furthermore, the tooling is reusable. The quick clamping and adjustment tooling adopts a modular clamping structure. After fine adjustment, it can be removed and put into the next work section for recycling without damaging the busbar shell and insulation layer, reducing the consumption of temporary support materials and the generation of waste.

[0021] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A construction method for rapid fixing and precision adjustment of busbars in power distribution engineering, comprising step 1 construction preparation and positioning layout, step 2 rapid installation of the support system, step 3 rapid busbar positioning and initial fixing, step 4 precise connection and precision adjustment, and step 5 inspection and system verification, characterized in that: Step 1, construction preparation and positioning, includes step 101, site condition verification and path planning, step 102, elevation and vertical transfer, and step 103, material and tooling placement. Among them, the rapid installation of the support system in step 2 includes step 201 base anchoring and initial leveling, step 202 adjustable column and crossarm pre-assembly, and step 203 rapid assembly of insulating pad and limiting component. Step 3, rapid positioning and initial fixing of the busbar, includes step 301, segmented hoisting and docking positioning, step 302, rapid clamping tooling intervention, and step 303, rapid fixing of vertical sections and bends. Among them, step 4, precise connection and precision adjustment, includes step 401, conductor lap surface treatment and bolt tightening, step 402, fine adjustment of overall straightness and perpendicularity, and step 403, adjustment of expansion compensation device and grounding bridging. Step 5, Inspection and System Verification, includes Step 501, Insulation Testing and Circuit Verification; Step 502, Point-by-Point Re-inspection of Fasteners and Anti-Loosening Measures; and Step 503, Cleaning and Handover of As-Completed Status.

2. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 101: On-site condition verification and route planning: Verify the handover documents for the power distribution room civil engineering, focusing on confirming whether the location of reserved holes, the elevation of embedded parts, the flatness of the ground, and the verticality of the walls meet the construction requirements. Use a laser rangefinder to scan along the design path of the busbar, mark the locations where it may intersect with other pipelines and equipment, and form a path conflict list. Based on the busbar phase sequence and branch interface locations on the design drawings, mark the center line of the busbar and the cross lines for the bracket positioning on the ground. The deviation of the center line should be controlled within ±2mm. For long straight sections of the busbar, mark the installation location of the compensator in advance on the path line according to the principle of setting an expansion compensation unit every 9m. Step 102: Elevation and Vertical Transfer Based on the elevation benchmark provided by the civil engineering in the power distribution room, a level instrument is used to transfer the +1.0m elevation line to all busbar installation walls and columns, and a continuous horizontal line is marked with a chalk line. For multi-layer busbar installation areas, according to the common parameters of 250mm between phase centers and 150mm between phase conductor centers, the bottom elevation line of each layer of busbar is marked layer by layer. For the vertical section of the busbar path, a plumb line combined with a theodolite is used to transfer the vertical line from top to bottom in the shaft. A vertical benchmark point is marked on the wall every 1.8m, and the verticality deviation between two points is no more than 1.5mm. Step 103: Materials and tooling in place: Inventory the incoming high-density busbar trunking and accessories, verify the section number, rated current level (e.g., 2000A / 2500A), and protection level markings, check for any bumps or damage to the insulation boards, and ensure the silver plating on the conductor lap surfaces is intact. Prepare specialized tooling, including an adjustable busbar positioning bracket, a hydraulic lifting platform, a laser collimator emitter set, a torque wrench (calibrated and with a range covering 70-100 N·m), non-metallic impact pads, a phase-to-phase insulation resistance tester, and a quick-clamping and adjustment tooling consisting of a channel steel base, a graduated sliding seat, and a horizontal fine-tuning screw.

3. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 201: Base anchoring and initial leveling: At the pop-up crosshair positioning point, install hot-dip galvanized channel steel bases. Use rear-expanded bottom anchor bolts to fix the bases to the concrete structure, with an anchoring depth of not less than 80mm. Use 4 anchor bolts diagonally to fasten each base. After the bases are installed, use a level to measure the elevation of their upper plane. By inserting stainless steel adjusting shims at the bottom, control the deviation between the elevation of each base and the design elevation to be within 0 to -1mm. The center distance between adjacent bases on straight sections is set at 1.5m. Add reinforcing supports at bends, branches, and ends, with a center distance not exceeding 0.5m.

4. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 202: Pre-installation of adjustable columns and crossarms: Embed the C-shaped steel column into the socket of the base. The column has elongated holes on all four sides. The vertical adjustment stroke is ±30mm. Do not lock the connecting bolts first. Insert the crossbeam and adjust it to be horizontal with a magnetic level. When inserting the crossbeam into the column, insert it into the corresponding hole according to the elevation of the generatrix of each layer. Initially tighten the anti-loosening nut. Use a straightedge to check the vertical flatness of the left and right columns of the same section. Adjust the translation position of the column in the base so that the sides of the entire column are on the same elevation, with the deviation controlled within 1mm / m. Then use an electric wrench to tighten the clamping bolts between the column and the base with a torque of 40N·m to form a rigid portal frame.

5. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: The rapid assembly of the insulating pad and the limiting component in step 203: Insert the SMC insulation pads into the pre-set T-slots on the crossarm. The spacing between the pads should be controlled according to the busbar width + 1.5mm. After the pads are placed, insert the nylon phase-separating blocks. The blocks have elastic buckles that can be pressed down to fix them. Install detachable lateral limiting angle steel at the end of the crossarm. The vertical surface of the angle steel is covered with 3mm thick epoxy fiberglass cloth to form the lateral constraint boundary of the busbar. The entire support section is now assembled. Check that all insulation components are free from skewing or looseness.

6. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 301 involves segmented hoisting and docking in place: Using a hydraulic lifting platform, a section of busbar unit is lifted to a position approximately 20mm above the designated elevation. It is then slowly advanced between the two supports. The operator holds a laser collimator and attaches it to the side of the conductor of the installed busbar section. The beam is projected onto a target on the side of the conductor of the section to be positioned. The operator directs the lifting platform to make minor adjustments until the beam aligns with the center line of the target. After confirming alignment, the lifting platform slowly descends, allowing the busbar body to rest smoothly on the insulating pad. At this point, the limiting angle steel naturally restricts its left and right sway. The guide positioning pin at the connector is inserted to initially tighten the two busbar sections, but not lock them in place.

7. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 302 involves the rapid clamping fixture intervention: Insert the sliding seat of the quick-clamping adjustment fixture into the lower flange of the support channel steel. The end of the lateral fine-tuning screw of the fixture abuts against the side plate of the busbar. Configure one fixture every 3m for the straight section. First, tighten the longitudinal tensioning component with a wrench to eliminate the gap between sections. Make the compression of the insulating partition at the joint reach 0.2-0.3mm and visually fit. Then, alternately adjust the left and right lateral fine-tuning screws. According to the laser target reading, adjust the horizontal straightness deviation of the busbar to within 1.5mm / 10m. After completion, lock all the wing nuts on the fixture to form a temporary rigid fixation. Step 303: Quickly fix the vertical section and bend: Inside the vertical busbar shaft, pre-installed load-bearing supports are used as the lower support points. The upper part is hoisted with ropes to hang the bend and vertical section. A clamp-type sliding support is installed in the middle of the vertical section. The clamp is lined with a silicone rubber buffer pad, and the tightening torque is controlled at 15 N·m. This prevents the busbar from sliding under its own weight and also leaves axial sliding margin for thermal expansion and contraction. Anti-vibration supports are added 1m on each side of the bend. The supports are pressed against the busbar with U-shaped pressure plates and butterfly-shaped spring pads to prevent micro-displacement caused by electromagnetic forces during operation.

8. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 401: Conductor lap joint surface treatment and bolt tightening: Remove the connector cover plate and wipe the conductor lap surface with anhydrous alcohol. If there are slight oxidation spots, use fine sandpaper of 400 grit or higher to polish and clean along the length of the busbar. Insert the 8.8 grade galvanized fastening bolts and apply torque in three stages in a diagonal sequence: first, pre-tighten to 30% of the target torque; second, to 60%; and third, tighten to the design torque value using a calibrated torque wrench. Common torque parameters for copper busbar lap connections are: 70 N·m for M12 bolts and 90 N·m for M16 bolts. After tightening, use a 0.02 mm feeler gauge to check the lap surface around the perimeter. The insertion depth should not exceed 10% of the lap surface width. Step 402: Fine-tuning of overall straightness and perpendicularity: Remove some of the temporary clamping fixtures, leaving only the fixtures at the beginning and end. Use a laser collimator to scan along the entire length, and provide feedback on the straightness deviation in segments. For local points that exceed the standard, loosen the connecting bolts between the crossarm and the column of that section of the support, and insert U-shaped adjusting shims of 0.5mm, 1mm, and 2mm thickness to change the pitch angle and horizontal displacement of the crossarm until the beam offset falls back to within 2mm / length. For the vertical section, adjust the verticality through the turnbuckles at the top of the shaft. Under the monitoring of the theodolite, correct the tilt to no more than 1‰. After correction, re-tighten all support connectors. Step 403: Adjustment of the expansion joint compensation device and grounding bridging: At the busbar compensator installation location, loosen the temporary spacing plates at both ends of the compensator, measure the gap between the busbar ends on both sides of the compensator, and adjust the gap to the calculated value by using the guide rod nuts inside the compensator, based on the difference between the ambient temperature and the design temperature and referring to the empirical value of reserving a gap of 1.5mm for every 10℃ temperature difference. The allowable deviation is ±0.5mm. At the same time, install the braided copper strip grounding jumper, with a cross-sectional area of ​​not less than half of the phase conductor cross-sectional area. Clean the crimping surfaces on both sides with a copper brush, and tighten the bolts to the same torque as the phase conductor. The grounding jumper at the compensator should have a 40mm expansion bend to accommodate the thermal displacement of the busbar.

9. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 501: Insulation test and circuit verification: After all fine-tuning is completed, remove all temporary fixtures and jumper clamps. Use a 2500V megohmmeter to measure the insulation resistance between each phase conductor and between the phase conductor and the outer casing. The test value must not be less than 50MΩ. For busbar systems with a length of more than 100m, calculate the total insulation resistance after segmented testing to confirm that there are no missing grounding points. Then, use a phase sequence table to verify that the phase sequence of each segment and branch circuit is consistent with the system design drawing. Double confirmation is made at the end and intermediate branch boxes, and the connection of the N line and PE line conductors is checked simultaneously. Step 502: Re-inspect fasteners and anti-loosening measures point by point: Working in pairs, one person uses a torque wrench to check the torque of all connecting bolts, while the other records and applies paint to confirm. The check proceeds from the power inlet to the load end, focusing on checking each bolt at the connector, branch plug-in box interface, compensation device, and grounding jumper. In areas with vibration, self-locking inserts are added to the nut ends or thread-locking agent is applied to prevent loosening during long-term operation. All paint marks are covered with different colored paint to facilitate inspection and traceability.

10. The construction method for rapid fixing and precision adjustment of busbars in power distribution engineering according to claim 1, characterized in that: Step 503: Cleaning and handover of completed status: Clean the inside of the busbar trunking, joints, and surrounding area of ​​metal debris, tools, and foreign objects. Blow dry compressed air onto the surfaces of conductors and insulators. Restore all end caps, joint covers, and protective baffles. Confirm that the IP protection level sealing strips are not warped. Compile construction records, including insulation resistance test values, torque re-verification lists, expansion gap adjustment records, and measurement and layout deviation charts, and submit them along with the as-built documentation. Finally, remove the construction area fencing, clear tools and remaining materials out of the power distribution room, and complete the site restoration.