Construction Procedures for Oil-Immersed Transformers

　　The construction of oil-immersed transformers is a complex and meticulous process involving multiple critical steps to ensure the safe and stable operation of the transformer. Below are the main construction procedures for oil-immersed transformers:

　　I. Construction Preparation

　　Technical Preparation:

　　Familiarize with the construction drawings and technical specifications to clarify construction requirements and standards.

　　Prepare a construction plan and safety technical measures, and conduct technical briefings and safety training for construction personnel.

　　Material Preparation:

　　Check whether the model, specifications, and quantity of the transformer meet the design requirements.

　　Prepare the necessary construction materials, such as insulating oil, sealing materials, fasteners, etc., and ensure their quality is up to standard.

　　Tools and Equipment Preparation:

　　Prepare the required tools and equipment for construction, such as cranes, forklifts, vacuum pumps, oil injection equipment, etc., and check their performance to ensure they are in good condition.

　　Site Preparation:

　　Clear the construction site to ensure it is free of debris and standing water.

　　Erect construction platforms or scaffolding to facilitate the operation of construction personnel.

　　II. Transformer Positioning and Installation

　　Transformer Positioning:

　　Use a crane or forklift to lift the transformer smoothly to the installation position, taking care to avoid collisions and vibrations.

　　Adjust the levelness and perpendicularity of the transformer to ensure it meets the installation requirements.

　　Accessory Installation:

　　Install accessories such as radiators, oil conservators, gas relays, and pressure relief valves on the transformer, and ensure they are tightly connected and free of leaks.

　　Connect the incoming and outgoing cables or busbars of the transformer, ensuring correct and secure wiring, and properly insulate the connections.

　　III. Insulating Oil Treatment and Oil Injection

　　Insulating Oil Treatment:

　　Treat the insulating oil by filtering, degassing, and dehydrating to ensure its insulating performance and cleanliness meet the requirements.

　　Use a vacuum oil filter to recirculate the insulating oil until the oil quality is qualified.

　　Oil Injection:

　　After the transformer is positioned and the accessories are installed, begin the oil injection operation.

　　Use oil injection equipment to slowly inject the treated insulating oil into the transformer, while observing the changes in the oil level gauge to ensure the oil level is within the specified range.

　　Pay attention to exhausting air during the oil injection process to avoid air bubbles forming inside the transformer.

　　IV. Electrical Testing and Commissioning

　　Electrical Testing:

　　After the oil injection is completed, conduct electrical tests on the transformer, including insulation resistance testing, DC resistance testing, dielectric loss testing, and turn ratio testing, to verify whether the electrical performance of the transformer meets the requirements.

　　Perform an AC withstand voltage test to check whether the insulation strength of the transformer meets the design requirements.

　　Commissioning:

　　Commission the protection devices and control devices of the transformer to ensure they operate accurately and reliably.

　　Conduct no-load test runs and load test runs to observe the operating status of the transformer and record operating parameters such as temperature, voltage, and current.

　　V. Acceptance and Handover

　　Acceptance:

　　After the construction is completed, organize relevant personnel to conduct acceptance checks to verify whether the installation quality and electrical performance of the transformer meet the design requirements and relevant standards.

　　Rectify any issues identified during the acceptance check until it passes the acceptance.

　　Handover:

　　After the acceptance is qualified, hand over the transformer to the user and provide relevant technical documents and operation manuals.

　　Train the user's personnel to familiarize them with the operation and maintenance methods of the transformer.

　　VI. Precautions

　　Safe Construction:

　　Strictly adhere to safety operating procedures during the construction process, wear personal protective equipment, and ensure construction safety.

　　Conduct regular safety inspections of the construction site to promptly identify and eliminate safety hazards.

　　Quality Control:

　　Strictly control the construction quality during the construction process, and conduct quality inspections and acceptances for each process.

　　Focus on monitoring and recording key processes and concealed works to ensure the traceability of construction quality.

　　Environmental Protection:

　　Pay attention to environmental protection during the construction process to avoid causing pollution to the surrounding environment.

　　Classify and dispose of the waste generated during the construction process to achieve resource utilization and harmlessness.