Diamond dotted paper is an insulating material that coats special modified epoxy resin on electrical insulation paper in a diamond shape. It is widely used in interlayer insulation and interturn insulation of oil-immersed power transformers. The following is a summary and answer to common questions about diamond dotted paper:
Material composition: Diamond dotted paper is composed of special modified epoxy resin and electrical insulation paper, and the resin coating is distributed in a diamond shape.
Curing process: When used, the coating layer begins to melt at a certain temperature during the drying process of the coil, producing an adhesion effect, and begins to solidify as the temperature rises, so that the adjacent layers of the winding are reliably bonded into a fixed unit.
Performance characteristics: It has excellent insulation performance, heat resistance and bonding strength, can prevent the displacement of the winding layers during short circuit, and ensure the long-term mechanical and electrical properties of the insulation structure.
Curing conditions:
The curing conditions of diamond dotted paper are usually 90℃±5℃ for 3 hours, and then heated to 125℃±5℃ for 6 hours.
It can also be cured according to the curing conditions specified by both the supply and demand parties.
Storage conditions:
It should be stored in a dry, clean and ventilated place at no more than 35℃ (some say no more than 30℃ or 25℃).
It should not be close to fire, heating, and avoid direct sunlight.
The storage period is 12 months. If it exceeds the storage period, it can still be used after passing the inspection.
Application range:
Diamond dotted insulation paper is mainly used for interlayer insulation and interturn insulation of oil-immersed power transformers.
It can also be used as cable shielding isolation layer and anti-corona material for high-voltage motors and electrical appliances.
Performance requirements:
Diamond dotted insulation paper should meet certain technical indicators, such as substrate thickness and tolerance, oil absorption, bonding strength, breakdown voltage, etc.
The bonding strength of epoxy resin should be sufficient to prevent displacement of winding layers during short circuit.
Function of resin coating:
The resin coating is distributed in dots, which ensures the immersion of oil and the discharge of gas in the insulating material.
It effectively avoids corona and partial discharge, thus ensuring the safety and reliability of the insulating structure.
When using diamond dotted paper, the operation should be strictly in accordance with the product instructions and curing conditions.
When storing, it should be kept dry, clean and ventilated, and avoid high temperature and direct sunlight.
Regularly check the performance indicators of diamond dotted insulating paper to ensure that it meets the requirements of use.
In summary, diamond dotted insulating paper has broad application prospects in fields such as power transformers, but it is also necessary to pay attention to its curing conditions, storage conditions and performance indicators during use.
