In the early 70 s, Shanghai and Beijing transformer factories successively developed thick insulation with quartz powder packing vacuum pouring cast resin dry type transformer
, from that time, the dry type transformer has officially become a new generation of products in our country, though it had some problems on the materials, manufacturing process and store and was later replaced by pure epoxy resin thin insulation technology, it is a good start for dry type transformer, which promote the development of dry type transformer technology in China.
Thick insulation (6mm) is difficult to solve the cracking problem, just when people have doubts about the epoxy resin dry type transformer technology, China successfully introduced from Germany pure epoxy resin thin insulation (1-3mm) technology without quartz packing, it appeared, so that our dry type transformer technology has rapidly developing. The product quality of this technology is stable (using imported pouring equipment and imported resin), and the user is satisfied. Plus at that time the factory has a better economic efficiency, we have started. First more than 10, then 30, 70, and now more than 100. At present, it has accounted for 90-95% of the dry change market, and its annual production capacity has exceeded 30 million kVA. Supply is much better than demand. This type of transformer is familiar to all of us, so we don’t need to talk much about it.
At the beginning of this century, the vacuum pouring dry type transformer with h-class insulating tape packing epoxy resin was developed in China by using American technology. He successfully solved the technical problems of insulation coordination, technical formulation and even pouring of various insulation components inside the transformer. Its emergence raised the insulation rating of epoxy dry type transformers from class B and F to class H.