I. Bus design overview
Installation of 220kV busbars, employing single section double busbar connection, with HGIS external suspension tube busbar in two row arrangement.
Installation of 110kV busbars, using double busbar connection, with HGIS external suspension tube busbar in two-row layout.
Installation of main transformer and rigid busbar of 10kV bus bridge.
Installation of equipment connections and conductive wires.
II. Construction Preparation
(1) Technical Preparation
The project team is organized to carefully study drawings and perform self-inspection and review to ensure accurate and error-free construction. Through the study, become familiar with the content of the drawings, understand the technical standards to be achieved by the project requirements, and clarify the process flow.
Self-inspection is carried out by organizing the construction management personnel of each trade to review the relevant drawings of their own trades, familiarize themselves with and master the details of the drawings. All professional construction teams are organized to study construction drawings together.
A design review meeting is organized, with the design side conducting the briefing, understanding the design intent and construction quality standards, and accurately understanding the details in the design drawings.
Ensure a good technical construction briefing, ensuring that each process is organized according to technical specifications and measurements.
Implement the quality inspection system strictly, carry out quality and safety checks, and eliminate any potential quality and safety risks.
(2) Resource Preparation Plan
1. Work Preparation
| No. | Job type | Number of personnel |
| 1 | Management Personnel | two |
| two | Electrician | two |
| 3 | Welder | two |
| 4 | High altitude worker | 4 |
| 5 | General Worker | 10 |
| Total | 20 |
2. Major Machinery Requirements Plan
| No. | equipment name | Model Specifications | Amount |
| 1 | Top Bending Machine | 1 unit | |
| two | Argon Arc Welding Machine | WSME-500 | 1 unit |
| 3 | Soldering machine | BX1-500 | 1 unit |
| 4 | Soldering machine | BX1-315 | 1 unit |
| 5 | Cutting machine | GQ40 | 1 unit |
| 6 | Bench Drill | ZQ3032×7 | 2 units |
III. Bus construction measures and technical requirements
(1) Flexible busbar and wire clamp of your equipment, hardware incoming goods inspection
1. Check the bus nameplate, certificate of conformity, specifications, model according to bus equipment table, as well as nameplate, certificate of conformity, specifications, equipment clamp model and hardware.
2. The appearance of the busbar must be smooth, without deformations, twists, loose wires or obvious signs of corrosion.
3. The appearance of the equipment wire clamp and hardware should be smooth, without burrs, deformations, irregularities, sand holes, rust slide buckles and other defects.
4. The cut-off of the fully supplied closed bus and plug-in bus slot must be clearly marked, with complete accessories, without deformation of the housing and without internal damage. The overlapping surface of the screwed busbar must be flat and its galvanized finish must not be pitted, peeled or exposed.
5. Installation holes of various metal components should not be cut or blown out by gas or electric welding.
(2) Bus pitch measurement
1. The length error of the cross beam should not be more than 10-15mm, and the error of the distance between the hanging plate and the A-shaped rod of the frame should not be more than +30mm or less than -30 mm.
2. The phase-to-phase error of the structure cross beam hanging plate should not exceed 10-15mm, and the three-phase distance should be consistent.
3. The screw hole distance of the frame cross beam suspension plate should not exceed 3-5mm, and the direction and size of the hole distance should be consistent.
4. Slope measurement should be carried out in windless conditions or less than level 3, using a steel tape measure (greater than 50m) with good strength and flexibility. The measurement error should not exceed 5mm.
(3) Cutting and crimping busbars
1. During the process of unwinding the busbar, the wire must not touch the ground or become twisted. A jack must be used to support the wire shaft. If the wire is kinked, broken or visibly loose, or if the damaged area in the same cross-section exceeds 5% of the conductive part, it must be replaced and not used.
2. Special tools must be used to cut the thread, and the cut end must be tied tightly. The wire must not be tangled, damaged or have a damaged steel core.
3. Wire crimping must use hydraulic or screw connections, and explosive crimping must not be used.
4. The specifications and clearances of the flexible busbar and metal parts must correspond to and must comply with current national standards.
5. There should be no connection joints within the pitch of flexible busbar and combined wire, and a special wire clamp should be used for connection to the jumper.
6. When the soft busbar is driven into the equipment by a screw tension clamp, it must not be cut and must become a single entity.
7. Before crimping the wire, the oxide film on the contact surface of the wire and the wire clamp must be cleaned in advance, and the cleaning length must be 1.2 times the crimping part. The crimping length of the equipment voltage clamp or wire clamp must reach the specified length.
8. The steel mold used for hydraulic pressure must match the pressed part. During crimping, the position and direction of the wires and wire clamps must be correct and must not be pressed crookedly. Each die crimp should overlap by 5 to 10 mm and burrs should be removed after crimping.
9. The hexagonal size at the corners after crimping should correspond to 0.866 times the outer diameter of the tube. When it exceeds 0.866+0.2mm, the steel mold must be replaced immediately.
(4) Installation of flexible busbars
1. The three-phase clearance of buses in the same pitch must be consistent during production. Similarly arranged branches or split conductors must also have the same curvature and looseness.
2. The looseness of the busbar must be in accordance with the design drawings, and its error range is between +5% to -2.5%.
3. When installing the combined busbar, the fixed wire clamp, various accessories and spacer rods must be complete, and the distance error in the conductor must not be more than +3% to -3%. Installation must be firm.
4. When installing the combined busbar, the hanging porcelain bottle, U-ring, hanger connecting plate steel anchor and fixed accessories must coordinate consistently, and the fixed reliable pin must be complete.
5. Appropriate suspension points must be selected when hoisting the conductor onto the girder. Mount the bus connectors on the ground and lift them into position tied to the steel cable.
(5) Inspection of pipe buses and equipment wire clamps and accessories
1. Check the input piping bus nameplate and certificate, specifications, models, equipment wire clamps, connection nameplate, certificate, specifications and models.
2. The appearance of the pipe bar must be smooth, free from deformation and obvious damage or corrosion.
3. The appearance of the equipment wire clamp and accessories should be smooth, free from burrs, deformations, irregularities, sand holes, rust slide buckles and other defects.
(6) Tubular busbar processing
1. Before cutting the tube, calculate the welding length of each aluminum tube based on the cross-sectional view of the entire busbar and the length of the delivered tube. Make sure the bus butt weld location is at least 50mm away from the pillar insulator fixing device and avoid the jumper device installation location between each gap. The cutting surface of the pipe must be flat and perpendicular to the axis. The casing tube must be cut according to the design drawings.
2. Use a chamfering machine to pre-process the chamfer of each pipe joint. The bevel must be smooth, uniform and free of burrs. For example, if the busbar thickness is 7 mm, the processed product must meet the following standards: blunt edge thickness 1.5 mm, bevel angle 60-70°. If the thickness of the busbar is 5 mm, the processed product must meet the following standards: blunt edge thickness 1 mm, chamfer angle 60-65°.
3. Use a bench drill to process reinforcement holes in the tubular busbar joint according to the drawings. Finally, align each tube on the correction platform until it meets the specification requirements.
(7) Pipe bus welding
1. Due to the length of the tubular busbar, a welding track must be installed at the welding site so that the tube can rotate freely and move laterally, making it easier to assemble the welding operation machine. The welding guide rail is directly welded with five 6m steel grooves (14), and rollers are installed on the top of the groove steel groove (one pair every 1m). During processing, it is necessary to ensure that the bending displacement of the groove steel and the roller axis is ≦0.2%, the axis displacement is ≦0.5mm, and the horizontal error is ≦3mm. After the guide rail is processed, it should be placed according to the actual situation on site, ensuring good coordination with the main machine tools.
2. Before welding, the surfaces on both sides of the bus groove within a range of 50 mm must be brushed clean. Oil contamination within 50 mm of the groove and the sides of the groove can be cleaned with a white cloth dampened in acetone. After drying, clean it with a clean stainless steel brush until the shine of the metal is revealed, and weld it immediately to prevent oxidation again.
3. Lift the aluminum tube to the welding guide rail, adjust the aluminum tube to make its butt joint straight, the bending displacement is ≦0.2%, the centerline displacement is ≦0.5mm and the gap between the top tubes is 1 mm.
4. Pipe busbar welding adopts argon arc welding. To prevent the resistance of the tubular busbar from decreasing after welding, measures are taken to compensate for the melting point of the liner tube. The longitudinal axis of the reinforcing casing should be in the center of the weld seam, and the gap between the casing and the pipe busbar should be less than 0.5 mm.
5. There are no special requirements for the tubular busbar welding process. Windproof measures must be taken during the welding process.
6. When welding, first locate the reinforcement hole for welding, and then weld the busbar and casing tube firmly into the groove. During the welding process, the welding gun should always keep the welding flat, and other people should slowly rotate the aluminum tube at both ends to ensure a uniform thickness of the welding seam. The upper part of the bus butt joint weld shall have a reinforcement height of 2-4 mm, the weld shall be arc-shaped, all weld seams and weld points shall be flat and smooth, and shall not there are burrs, irregularities and visible cracks, depressions, lack of meat, incomplete welding, pores, slag, etc.
7. Each weld must be completed at once and welding must not be interrupted except in the case of instantaneous interruption of the arc. The tubular busbar must not be moved or subjected to force before the weld is cooled. If the busbar needs to be turned, force should be applied to both ends and the middle at the same time to avoid excessive force on the weld.
(8) Bus installation
1. Before installing the busbar, according to the busbar segment number, clarify which busbar segment corresponds to which length and in which phase it should be installed to avoid installation in the wrong position.
2. Insert a damper wire into each busbar as per project requirements. Install the end cap or end ball, paint it the color of the stage, and make sure the water drop hole of the end ball is facing down. Before installing the bus, the bus hardware must also be pre-installed for one-time installation.
3. Because the bus length is relatively large, to prevent the bus from bending and deformation during installation, multiple points should be used for installation to improve accuracy. The safety factor of the sling strength should not be less than 5, the angle of the lashing rope should not exceed 90°, and the lashing points on the bus should be non-slip and easy to release.
4. When the busbar is 100mm off the ground, stop lifting it, clean the busbar again, and drill a Φ6mm water drip hole near the lowest point of each busbar segment (avoiding the welding part) . Check the power situation of the sling and busbar. Continue lifting only after confirming that there are no conditions that could affect the lifting process.
5. During the lifting process, always pay attention to the level of the bus. The two cranes must be under unified control and relatively balanced lifting (ensure that the boom height difference is ≤500mm), so that each lifting point is basically uniformly tensioned. If there are irregularities, adjust them before continuing the installation. Finally, gently lift it to the actual installation position and fix the busbar with the hardware on the support insulator.
(9) Bus adjustment
1. After installing the bus, check and adjust the level of the three phases and the error of the same distance. You can add or subtract shims to the bottom of the support insulator to ensure the horizontal and longitudinal level of the bus and keep the bus elevation in line with design requirements. The axis of the same phase segment is in a vertical plane, and the axis of the three-phase bus segment is parallel to each other.
2. Adjust the fixed and movable bus clamps according to the drawing requirements. Please note that there should be a gap of 1-2 mm between the movable type shaft seat and the busbar. The distance between the expansion joint and the clamp must meet the design requirements to prevent the busbar from becoming stuck due to thermal expansion and contraction.
(10) Installation of Equipment Lowering Line
1. Crimping of the equipment lowering line must meet the requirements of Article 3.3;
2. When the equipment lowering line clip is connected to the equipment terminal board, the surface oxide layer should be removed and the conductive compound grease should be applied. The screws must be tightened, exposing 2-3 threads.
4. Quality Control Measures for Construction
1. Carry out construction strictly in accordance with drawings, specifications for construction of electrical device buses and work instruction manuals.
2. Quality inspectors must participate and carry out random inspections during the processing, crimping and installation of flexible busbars and tubular busbars. For certain projects, supervisory personnel will be required to carry out random inspections.
3. Strictly control construction errors, check the quality of procedures in a timely manner, and correct any problematic procedures to prevent them from entering the next procedure.
4. Strictly control the quality of busbar crimping and welding.
5. Keep a record of the construction process on time and complete installation records promptly.
V. Occupational Health, Safety and Environmental Management Measures
(1) Security Measures
1. Firmly implement the construction policy of “safety first, prevention-oriented and comprehensive management”.
2. Construction personnel entering the site must strictly comply with the supervision of safety inspectors and construction managers. Strictly follow safety management rules and regulations and construction safety procedures, and conscientiously fulfill the safety duties of construction personnel at all levels.
3. Before construction, check the safety and reliability of construction tools. Construction personnel must wear qualified construction protective equipment for safety.
4. Carry out technical dissemination work and issue security work order tickets.
5. Construction machines must be guided by on-site technical personnel to avoid blind and illegal operations.
6. Hydraulic workers and argon arc welding workers must be certified to work to avoid illegal operations.
7. Special measures must be taken to protect the equipment when the bus is lifted into place.
8. It is strictly prohibited to drop objects from high places and throw things. Small ropes should be used for lifting.
9. Workers working at high altitudes should wear safety belts, dress comfortably, wear soft-soled shoes, and pay attention to observing working conditions on the ground. Pass items using a tool bag to avoid throwing and dropping objects from high places.
10. Carry out civilized construction and ensure that “all materials are exhausted after the work and that the site is clean”.
(2) Sources of Hazard and Pre-control of Hazardous Sources
1. The main hazards during construction are: work at high altitudes and mechanical construction.
2. Pre-control measures for sources of danger:
2.1 A special person must be installed at the workplace.
2.2 Climbing personnel must wear safety-qualified protective equipment such as safety belts and foot buckles. Climbing personnel must carry nylon ropes to pass tools and prevent objects from falling from high places. Before construction, carefully check the mechanical performance of the machinery (manual rectification), check whether the wire rope has broken wires, and whether the pulleys and buckles meet the tension requirements of the wires to be lifted.
2.3 Before construction, carefully check the condition of the machinery. Machines with problems will not be allowed to enter the construction site.
2.4 The responsibility for safety is clear and the pre-work safety briefing is in place, so that each construction personnel can truly understand the safety precautions that must be taken in each process, ensuring the safety protection function of the production line front of the construction.
(3) Environmental and Occupational Health Measures
1. Establish a responsibility system for environmental protection, strengthen publicity and educational work, and encourage workers to conscientiously implement environmental protection measures. During the construction process, prevent and minimize the impact on the construction site and the environment.
2. Construction waste must be centrally managed (stored and treated), and must not be discarded arbitrarily, causing environmental pollution.
3. During and after the project construction process, the ecological environment that was damaged during the construction process should be repaired and restored in a timely manner, and greening measures should be adopted as much as possible.
4. Construction and construction project domestic water should be organized and treated rationally according to the separation of clean and polluted water.
SAW. Standard Process Requirements
List of default process applications
| Serial number | Process number | Process name | Part of the application | Process Standard |
| Outdoor distribution equipment 220kVOutdoor distribution equipment 110kV | ||||
| 1 | 010******* | Insulating Rope Set | Insulating Rope Set | (1) The appearance of the insulator and the quality of the ceramics are intact, without damage. The cast steel parts are in good condition, no rust. (2) The connecting hardware corresponds to the bus conductor in use. The hardware and fasteners are smooth, without cracks, burrs or irregularities. (3) The elastic pin must have sufficient elasticity. The pin opening must not be less than 60° and there must be no breaks or cracks. The use of wire as a substitute is strictly prohibited. (4) The adjustment nut of the adjustable hardware is securely locked. |
| two | 010******* | Installation of Pillar Insulators | Installation of Isolation Posts | (1) The deviation in elevation of the support should be ≤5mm, the deviation in verticality should be ≤5mm, and the deviation in flatness of the top surface should be ≤2mm/m. (2) The exterior of the isolation pillar must be clean, without cracks, the base must be firmly fixed, and the force must be evenly distributed. (3) The vertical error should be ≤1.5mm/m, the base flatness error should be ≤2mm, and the centerline error of each insulator column within the straight section of the busbar should be ≤5 mm. (4) The base must be firmly connected to the grounding network, with good conductivity. |
| 3 | 010******* | Installing the bus grounding switch | Installing the bus grounding switch | (1) The elevation deviation of the support should be ≤5mm, the verticality deviation ≤5mm and the flatness deviation of the top surface ≤2mm/m. (2) The insulator column must be perpendicular (error ≤1.5 mm/m) to the base plane and firmly connected. (3) The connecting screw between the insulator column and the base plane operating shaft must be tightened. (4) The smooth connection of the conductive part must be reliable and free from damage. (5) The terminal must be clean and flat and coated with power compound grease. (6) The operating mechanism must be firmly installed, the fixing bracket must be aesthetically pleasing, and the axis of the mechanism must coincide with the base axis, with a deviation of ≤1mm. (7) The arrangement of cables must be organized and aesthetically pleasing, and the fixing and protection measures must be reliable. (8) The grounding of the equipment base and mechanism housing must be firm and have good conductivity. (9) The operation must be flexible and the contactor contact must be reliable. (10) Grounding must be firm and reliable. (11) The installation of the equalizing ring must not have scratches or burrs and must be firmly installed, flat and free from deformation. The equalizer ring must have a drain hole at the lowest point. (12) The vertical connecting rod must be grounded with soft copper wire (supplied by the manufacturer) and must be marked in black. |
| 4 | 010******* | Downlead and Jumper Wire Installation | Arrangement of cross sections for each space and flat cross section of the main bus | (1) The positioning of the long span line clamp (T-shaped) is reasonable, with the down line and jump line looking natural and aesthetically pleasing, and the arc is appropriate. (2) The equipment line fixing direction (angle) is rational. (3) When installing the soft lead wire clamp with the mouth facing upwards, a drain hole with a diameter of no more than 8mm must be drilled at the bottom of the clamp. (4) The degree of curvature of the aluminum tube is less than 2%. (5) When crimping, the correct position of the wire clamp must be maintained, it must not skew, the overlap between the two adjacent dies must not be less than 5mm, and the size of the opposite hexagonal sides after crimping must not be larger than 0.866D+0.2mm (D is the outer diameter of the connecting tube). |
| 5 | 010******* | Installation of Suspended Tubular Bus | Layout of the flat cross-section of the main bus | (1) The busbar must be straight, with perfect ends and deflection less than D/2 (D refers to the diameter of the tubular busbar). (2) The three phases must be parallel and equally spaced. (3) Jumper wires must be oriented naturally and consistently across all three phases. (4) Hardware specifications must match the tubular bus. (5) The installation of the pressure equalizing ring must not have scratches or burrs, and must be installed firmly, flat and without deformation. The pressure equalizing ring must have drain holes at the lowest point. |
| Installation of the Main Transformer and 10kV Bus Bridge | ||||
| 6 | 010******* | Installation of the main transformer grounding wire | Installation of the main transformer grounding cable | (1) When flat steel is used for the grounding cable, it must be galvanized to protect against corrosion. (2) The grounding cable and the equipment body are screwed together with a tight overlap. (3) The grounding body connection is reliable and aesthetically pleasing. (4) The body and neutral point require two grounding points, each connected to different main lines of the grounding network. The neutral bus must be marked in light blue. (5) The above-ground portion of the grounding cable must be marked with yellow and green grounding symbols at consistent intervals and sequence, with the upper one being yellow. The width of the grounding symbol should be 15~100mm. (6) The neutral point of the transformer of 110kV and above, the clamp grounding cable and the body are reliably insulated. (7) A reliable jumper must be made between the upper and lower flanges of the bell-shaped body. (8) Test ground terminals must be configured in accordance with operational requirements. |
| 7 | 010******* | Insulating Rope Set | Installation of the Insulator String Main Transformer Assembly | (1) The insulator appearance and porcelain quality are in perfect condition, the cast steel parts are intact and rust-free. (2) The connecting hardware matches the bus conductor used, and the hardware and fasteners are smooth, without cracks, burrs or irregularities. (3) The elastic pin must have sufficient elasticity, the opening of the pin must not be less than 60°, and it must not have breaks or cracks. Wire substitutes are strictly prohibited. (4) The adjusting nuts of the adjustable hardware are securely locked. |
| 8 | 010******* | Flexible bus installation | Installation of the Main TransformerInstallation of the Main Transformer Lead Wires | (1) The wires must not have broken, loose or damaged wires, and the expanded wires must not have depressions or deformations. (2) The appearance of the insulator and its porcelain quality must be intact without damage, and the cast steel parts must be in good condition and free from rust. (3) The connecting hardware must match the wires, and the hardware and fasteners must be clean, without cracks, burrs or irregularities. (4) The drain plate must not be deformed or damaged. (5) The adjusting nuts of the adjustable hardware on the insulator string must be firmly locked. (6) The bus sag must meet the design requirements, with an allowable error of -2.5% to 5%, and the sag of the three-phase bus within the same span must be consistent. (7) The specifications and dimensions of the line clamp must match the specifications and model of the wire. (8) During crimping, the correct position of the line clamp must be maintained, it must not be distorted, the overlap between the two adjacent dies must not be less than 5mm, and the size of the opposite hexagonal side after crimping must not be greater than 0.866D+0.2mm (D is the outer diameter of the connecting tube). (9) The degree of curvature of the expanded wire should not be less than 30 times the outer diameter of the wire. (10) The degree of curvature of the aluminum tube should be less than 2%. (11) The installation of the equalizing ring must not have scratches or burrs, it must be installed robustly, flat and not deformed: the equalizing ring must have a drainage hole at the lowest point. |
| 9 | 010******* | Installation of overhead lines and jumpers | Installation of the Main TransformerInstallation of the Main Transformer Lead Wires | (1) The placement of staples on high transverse lines (T-shaped) is reasonable, and the direction of falling and jumping lines is natural and aesthetically pleasing with an appropriate radius. (2) The equipment clamp direction (angle) is reasonable. (3) When installing a soft conductive wire compression clamp with the opening facing upwards, a drain hole with a diameter of no more than 8 mm must be made at the bottom of the clamp. (4) The degree of curvature of the aluminum tube is less than 2%. (5) During crimping, the correct position of the clamp must be maintained and must not be distorted. The overlap between two adjacent molds should not be less than 5mm, and the dimension of the hexagonal opposite sides after crimping should not be greater than 0.866D+0.2mm (D is the outer diameter of the connecting tube). |
| 10 | 010******* | Rectangular bus installation | Main Transformer Bus Bridge InstallationRectangular Bus Installation | (1) The elevation deviation of the pillar insulator support should be ≤5mm, the verticality deviation should be ≤5mm, and the flatness deviation of the top surface should be ≤2mm/m. (2) Expansion measures must be taken between the bushing terminals of the main transformer. (3) Conductors and insulators must be arranged neatly with consistent distances between phases. The flatness deviation should be ≤5mm/m, and the height difference of the top surface should be ≤5mm. (4) The pillar insulators must be firmly fixed and the tightness of the conductor fixings must be appropriate. Except for the firmly attached ends, all others must be loosely attached to allow natural expansion and contraction of the conductor. (5) The fabrication of the rigid busbar must be level and vertical. The bending of busbar joints must meet the specification requirements and the number of joints must be minimized. (6) Support insulators should not be attached to bends. The distance from the edge of the clip from the attachment point to the bend must not exceed 0.25L. |
This construction plan is a working document used in conjunction with building regulations, standards and operating instruction manuals during construction. During construction, this plan must be referenced. In case of special circumstances, adjustments can be made as appropriate.
