The characteristics of epoxy resin are
The epoxy resin cast dry-type transformer has the characteristics of flame retardant, safety, reliable operation, convenient maintenance and small size. They have been widely used in urban high-rise buildings and power stations.
Epoxy resin generally refers to an organic polymer compound containing two or more epoxy groups in the molecule. Except for a few, their relative molecular mass is not high.
The characteristics of epoxy resin are:
① Various forms.
②Easy to cure
④ Low shrinkage.
⑤It has excellent mechanical properties after curing.
⑥After curing, it forms an excellent insulating material with high dielectric properties, surface leakage resistance and arc resistance.
⑨Mold resistance etc.
Epoxy resin has been widely used as the main insulating material in the field of power equipment manufacturing, such as transformers, transformers and insulators. The epoxy resin cast dry-type transformer has the characteristics of flame retardant, safety, reliable operation, convenient maintenance and small size. They have been widely used in urban high-rise buildings and power stations.
In the past ten years, the production of dry-type transformers in my country has made great progress, and the performance and appearance of the products have been greatly improved. Epoxy resin castings have the characteristics of one-time molding, that is, they cannot be recycled and hardened after being cooled and cooled. After molding, the winding does not meet the required standards or design requirements and can only be scrapped and cannot be reused.
The national standard GB1094.11-2007 stipulates that the maximum value of the partial discharge level of dry-type transformers is 10 PC. In order to ensure the quality of the winding, the structure of the prefabricated winding is required to be reliable, the proportion of casting materials is reasonable, and the technology is advanced.
Currently, most transformer industries use imported or domestic vacuum casting equipment. Due to the different structure of the vacuum casting equipment, it also has its uniqueness in the specific casting operation.
In the early 1990s, a complete set of vacuum casting equipment was purchased from BP2 in Italy. Next, take the winding casting process as an example to briefly discuss the vacuum casting process of the horizontal winding of a dry-type transformer.