Insulating Materials for Oil-immersed Transformers

Today, let’s take a look at the insulating materials for oil-immersed transformers. ZTelec Group supplies about ten types of materials, which are as follows:

1.The diamond dotted paper(DDP) is used to reduce the interlayer displacement of transformer winding as well as the temperature rise of transformer oil. The product is suitable for the winding interlayer insulation of amorphous alloy transformers and instrument transformers, etc.

2.The polyester unidirectional binding tape can be used for binding transformer iron cores.

3.The oil duct strip is made of rectangular electrical board strip and DDP bonded with special adhesive. The product can be firmly bonded to the winding coil, replacing the traditional corrugated container board which is easily deformed and produces displacement, so that the coil has better mechanical and electrical properties, and therefore widely used in oil-immersed transformers.

4.The electrical crepe paper is characterized by good oil solubility, widely used for lapping parts insulation and lead parts insulation wrapping in oil-immersed transformers, instrument transformers, and reactors etc., thus improving the electrical and mechanical properties of the product insulation structure.

5.The electrical crepe paper tube is mainly used as insulation wrapping material for the oil-immersed transformer leads.

6.The phenolic laminated paper tube with good dielectric properties, is suitable for transformer oil as insulation structural parts for electrical equipment in dry environments.Temperature resistance: E class 120 degrees Celsius.

7.The electrical pressboard is made of 100% pure sulphate wood pulp, with high chemical purity, good elongation rate, and great mechanical and electrical strength. It’s widely used in oil-immersed power transformers, reactors, capacitors, switches, etc., suitable for making bracing strips, paper tubes, pads, and end rings, etc.

8.The electrical laminated wood is mainly used as insulating and supporting materials in transformers and instrument transformers, suitable for making pressure plates for coil, core pads, trapezoidal pads, lead brackets, and fixtures etc. It has moderate specific weight, high mechanical strength, good solubility in transformer oil, and excellent processability etc.. Additionally, its dielectric constant is similar to that of the transformer oil, so it can be in 105 ℃ transformer oil.

The product is widely used to manufacture transformer structural components such as upper and lower pressure plates, lead brackets, yoke pads etc.; it’s also used to make jigs in transformers, which replaces steel plates, insulating pressboards and epoxy sheets, thus reducing the self-weight and material costs of transformers.

9.The electrical white cloth tape, made of cotton yarns, is widely used for general binding of coils on electrical appliances.

10.The electrical polyester high/low shrinkable tape has a certain degree of heat resistance and insulation, widely used as coil binding materials for motors, electrical appliances, and transformers.