Installation process and control points of enclosed combined electrical high-voltage switchgear GIS equipment

Analysis of GIS Equipment Installation Process
Pre - installation Preparations for GIS Equipment

First, use a crane to lift the equipment to the entrance. Then, insert a crowbar into the groove of the channel steel to move the equipment along the channel steel into the room. It can be received by a roller or a forklift for transfer. Before the equipment installation after the transfer is completed, sufficient preliminary preparations are required. Firstly, the equipment needs to be comprehensively inspected and tested to ensure it meets the design standards and specification requirements. Secondly, necessary maintenance and upkeep of the equipment should be carried out to guarantee its normal operation. Finally, detailed work plans and operating procedures need to be formulated and strictly implemented.

In actual work, the following points should be noted:

• The civil engineering, lighting, and decoration projects in the installation area must all be completed and pass the acceptance inspection.

• Professional supervisors are required to direct the hoisting during product installation.

• Ensure that the required lighting and power supply equipment can be used reliably before installation.

• An enclosed and lockable storage room should be set up near the work area at the installation site to store installation tools, parts, and other items, and a mobile tool cart should be equipped for transporting tools and parts.

• The installation area must be kept highly clean. The floor should be covered with floor leather, and the floor should be cleaned daily with a vacuum cleaner or mopped with a wet mop.

• A mobile power strip (380 V, 220 V) covering the entire installation area should be provided on - site.

• Personnel without permission are prohibited from entering the installation work area during product assembly.

The analysis of hazard points and preventive measures are as follows:
Hazard Point 1: Electric Shock to Personnel
Preventive measures are as follows:

• Before work, the work supervisor should inform all workers about the live parts adjacent to the work site.

• Carefully check the maintenance scope and enter the work only after confirming it is correct.

• Ground both ends of the equipment maintenance section.

Hazard Point 2: Toxicity of Gas Decomposition Products
The decomposition products of SF₆ gas under the action of an electric arc are highly toxic and can seriously affect physical health upon contact. Preventive measures are as follows:

• When the GIS cylinder is opened, personnel should stand upwind and ventilate for 0.5 hours.

• Personnel in contact should wear protective clothing and masks.

Hazard Point 3: Hazard of Gas Chamber Pressure
Preventive measures are as follows:

• Recover and fill SF₆ gas, and assign a dedicated person to monitor the equipment instruments.

• Only when it is confirmed that the recovered pressure of SF₆ gas meets the requirements of the plan can the bolts connecting the cover plate or flange be loosened.

GIS Equipment Installation Process
Responsibilities of GIS Equipment Manufacturers

During the pre - installation and installation process, the manufacturer conducts technical communication and liaison with relevant personnel, and provides installation training for those who install the product for the first time. The specific responsibilities are as follows:

• Provide technical documents related to installation.

• Offer technical guidance throughout the installation, adjustment, and testing processes.

• Inspect the assembled and cleaned internal components of the tank and conduct final quality verification.

• Provide items such as secondary wiring cables, cable tags, and terminal blocks from the local control cabinet to the product.

Responsibilities of the Installation Unit

Under the guidance of professional personnel from the GIS equipment manufacturer and the supervision of on - site supervisors, the installation unit is responsible for the following tasks:

• Transport and remove the outer packaging of the product.

• Hoist and position the GIS equipment.

• Assemble, clean, and inspect the internal components of the tank.

• Conduct operations such as vacuum - pumping, gas - filling, leak - detection by wrapping, and micro - water detection.

• Fabricate and install grounding plates, install product supports, maintenance platforms, and control cabinets.

• Perform various product tests, such as resistance tests, and characteristic tests of current transformers, voltage transformers, circuit breakers, grounding switches, and disconnectors.

• Tighten the bolts at all flange joints outside the tank.

• Lay cables and perform wiring work.

•  Apply anti - corrosion silicone grease in a timely manner at the flange joint positions during the product installation process.

Installation Process Control: First, conduct a detailed inspection of each bay to ensure it complies with the drawing requirements. Then, place the equipment bays or modules in their corresponding positions, clean them carefully with lint - free paper dipped in alcohol, and protect the interfaces. Next, connect the equipment bays, ensuring that the connections meet the technological requirements. Finally, conduct secondary debugging and testing on the entire system to ensure its trouble - free operation. In actual work, the following points need to be noted:

• Equipment selection is crucial. Products with reliable quality that are suitable for the on - site environment must be chosen. For example, in plateau areas with large temperature differences between day and night, heaters need to be installed in the equipment to ensure the stability of the internal SF₆ gas. In coastal areas, anti - corrosion structures need to be considered, especially for the terminal plates of bushings, which are prone to moisture - induced corrosion, so a gluing process should be added.

• Equipment installation must be carried out strictly in accordance with the drawing requirements to avoid potential safety hazards.

• The connections between equipment must be carried out meticulously to meet cleanliness requirements and prevent potential discharge hazards.

Inspection During GIS Equipment Installation Process

Both the metal surfaces and insulating surfaces of GIS equipment components should be carefully inspected and cleaned. Ensure that there are no scratches, uneven areas, or dust on the surfaces of all components, so as to guarantee a uniform internal electric field of the GIS equipment and its long - term stable operation.

GIS Equipment Acceptance

During the installation of GIS equipment, acceptance is a crucial step. Through comprehensive inspection and testing of GIS equipment, it can be ensured that it complies with design specifications and quality standards, and subsequent operations can proceed smoothly. In practical work, the following steps should be followed:

• Inspect the appearance of the GIS equipment to confirm whether there are any damages or defects.

• Check the wiring of the control cabinet and its mechanisms, including electrical circuits, sensors, heaters, and drive systems, to ensure normal operation.

• Test the electrical operating performance of the GIS equipment to ensure it meets the functional requirements for electrical operation.

For different types of GIS equipment, the specific acceptance methods may vary. For example, for the hydraulic spring mechanism of a circuit breaker, factors such as oil pressure, speed, and opening/closing time need to be measured and analyzed to determine whether its operating state is stable and reliable. For mechanical transmission devices, tests on characteristics such as motion accuracy and stability are required for evaluation.

Key Points of GIS Equipment Installation Control
Technological Requirements during GIS Equipment Installation

Construction workers should be familiar in advance with the basic construction methods and technical requirements according to relevant maintenance regulations or on - site maintenance plans. Upon the arrival of spare parts at the site, they should be unpacked and inspected immediately and compared with the on - site equipment. Before starting work, dedicated personnel should take inventory of and register spare parts and tools. If any damage or shortage is found, work is prohibited until they are replenished. During the equipment disassembly and restoration processes, actions must be slow to avoid collisions.During tank - opening maintenance, dust - proof and moisture - proof measures should be taken as follows:

• Set up a mobile maintenance box at the construction site to store disassembled components and maintenance tools.

• Equipment maintenance personnel should wear work clothes, safety helmets, and masks.

• The mating surfaces after equipment disassembly should be covered with dust covers immediately.

• Non - maintenance personnel should not frequently enter and exit the maintenance area.

• Special personnel should be responsible for checking the tools used for equipment maintenance to ensure nothing is left inside the equipment.

• Prevent dust, moisture, and fibers from entering and foreign objects from remaining inside the GIS equipment. Before replacing the adsorbent cover, a dedicated person should be assigned to do the final cleaning.

• The surface cleaning of the tank body and insulation parts is preferably carried out in a "suck - wipe" cycle.

The usage requirements for SF₆ gas recovery devices are as follows:

• The gas recovery device should be operated by personnel who have received special training and are familiar with the operation method.

• Before use, it should be confirmed that all parts of the recovery device are in good condition.

• During use, misoperation must be absolutely prevented to avoid contaminating the SF₆ gas or causing environmental pollution due to gas leakage.

• The recovery device should use dedicated hoses and be kept clean and dry.

Gas cylinders should be equipped with safety and vibration - proof rubber rings and clearly labeled to prevent confusion between old and new gases. Tank - opening work should be reviewed. The review work should be assigned to dedicated personnel, especially to check the tightness of internal screws. If necessary, review marks should be made on each screw, and then the person in charge should conduct a final inspection. The tightening torque of bolts should be applied as required by the manufacturer.The selection and usage requirements for lubricating greases and sealing greases are as follows:

• Lubricating greases for movable mechanical parts inside the GIS and for electrical contacts should be selected as required by the manufacturer.

• The layer of lubricating grease should not be too thick.

• When using vacuum silicone grease for all "O" - ring seals and flanges, avoid applying it to the inner side of the "O" - ring seal that comes into contact with the SF₆ gas.

The technological requirements for disassembly and assembly of sealing surfaces are as follows:

• Flange screws must be loosened diagonally along the circumferential direction.

• The sealing groove surface should not have scratches, and the sealing groove and flange plane should not rust.

• The grinding of damaged sealing groove surfaces should meet the manufacturer's requirements.

The technological requirements for replacing adsorbents are as follows:

• Adsorbents that are pre - treated and sealed - packaged at the factory can be used directly.

• Damaged or used bagged adsorbents must be dried before being installed.

• After the adsorbents are installed in the GIS, vacuum - pumping operations should be carried out immediately, and the time should be controlled within 30 minutes.

The technological requirements for vacuum - pumping are as follows:

• For disassembled gas chambers, pump to a vacuum of 40 Pa, continue pumping for 0.5 hours, stop the pump, and check the vacuum degree after 2 hours. If it is not more than 133 Pa, it is considered qualified. Fill with SF₆ gas to the rated pressure, and replenish the pressure in the depressurized gas chamber to the rated pressure.

• When detecting the vacuum degree, the McLeod gauge is strictly prohibited.

The technological requirements for filling SF₆ gas are as follows:

• When filling gas, first open the SF₆ gas cylinder and release a small amount of gas to prevent air from entering the GIS.

• Before use, the interface of the on - site gas - filling pipe should be cleaned, and after use, it should be properly stored and not placed on the ground to avoid introducing foreign objects during the gas - filling process.

• SF₆ gas cannot be directly filled into the gas chamber from the gas cylinder; it must be decompressed through a pressure - reducing valve.

• For SF₆ gas with sufficient micro - water content, the mass fraction of water should be less than 5×10⁻⁶, which is less than 40 μL/L when converted to volume ratio.

The technological requirements for local cover - type leak detection are as follows:

• The plastic cover (bag) should not have holes.

• All leakage points should be wrapped without omission.

• Detection personnel should be conscientious in detection, and the equipment and instruments should have good and reliable performance.

Inspection Work after GIS Equipment Installation

After the GIS equipment installation is completed, strict inspection and acceptance are required. Each component should be inspected in detail to ensure its quality and performance meet the standards. Then, a comprehensive inspection and test of the entire system should be carried out to ensure its normal operation and prevent potential safety hazards for users.

Only by carefully completing each step of the preliminary work can all tasks of subsequent work be successfully accomplished.

Effective Strategies for Optimizing GIS Equipment Installation Processes and Key Control Points
Implementing Safety Measures in GIS Equipment Installation

During the GIS equipment installation process, safety is a crucial aspect. To ensure the normal operation of the equipment and the safety of personnel's lives and property, a series of safety measures need to be taken, as follows.

Strengthening Inspection and Maintenance of GIS Equipment after Installation

• Pay attention to safety protection measures. During operation, relevant regulations and standards must be strictly adhered to. Appropriate personal protective equipment should be worn to avoid accidents. Meanwhile, management of the on - site environment should also be strengthened to prevent dust, oil stains, etc. from entering the interior of electrical components and affecting their normal operation.

• Monitor changes in equipment status. In daily use, attention should be paid to changes in the equipment's status, such as temperature rise and abnormal current fluctuations, so that corresponding measures can be taken in a timely manner.

• Maintain records and feedback. For any problems or defects discovered, timely recording and reporting should be carried out, and solutions should be submitted to relevant departments for improvement and refinement. Based on actual conditions, formulating a reasonable inspection and maintenance plan to enhance the safety performance and service life of the equipment is one of the important means to achieve efficient and stable operation of GIS equipment.

Improving the Quality Control of On - site Gas Filling for GIS Equipment

The inspection and maintenance requirements for gas pipelines are as follows:

• All connecting pipelines and connection components should be in good condition, clean, and free of oil stains. The connection between the pipeline and the product should be kept clean and can be wiped with lint - free paper dipped in alcohol.

• Before a pipeline that has been out of use for more than 10 days is reused, it needs to be purged and cleaned with high - purity nitrogen. After pipeline operations are completed, the connection heads should be sealed with plastic caps to prevent dust and foreign objects from entering.

Install filters at the gas - filling joints of pipelines to ensure the quality of gas filling.

Strengthening the Emergency Management of GIS Equipment

The specific measures for strengthening the emergency management of GIS equipment are as follows:

• In case of a malfunction, immediately stop the operation, notify relevant personnel for handling, and promptly contact the maintenance department or the technical support team of the manufacturer to resolve the issue quickly. In case of emergencies such as fires or explosions, evacuate the site as soon as possible to avoid casualties.

• In case of equipment damage, immediately stop the machine and notify the relevant department for handling. Meanwhile, isolate the damaged part to prevent other components from being affected. If necessary, temporary repair methods can be adopted to ensure the normal operation of the equipment.

• Pay attention to basic safety issues, such as the wiring method of electrical circuits and the selection of power supply voltage. In actual operation, strictly comply with relevant safety regulations and standards to ensure that the device can operate normally without endangering the surrounding environment.

Conclusion

In conclusion, during the installation process of GIS equipment, it is necessary to strictly comply with relevant standards and specifications to ensure the safe and stable operation of the equipment. At the same time, attention should also be paid to issues such as the connection methods and circuit layout between equipment to ensure the stability and reliability of the system. In addition, for the design of the control system of GIS equipment, it is necessary to fully consider the requirements and characteristics of the actual application scenarios and use advanced technical means for optimization and improvement. In general, enterprises should also focus on product research, development, and innovation, continuously improve product performance and quality, and meet the changing market demands and development trends.