A method for preparing an epoxy pet insulating cylinder suitable for casting dry-type transformers

Abstract

The invention discloses a method for preparing an epoxy PET insulating cylinder suitable for casting a dry-type transformer, which comprises: 1) crushing and pulverizing PET non-woven fabrics to obtain pulverized PET short fibers, the length of which is less than 10 mm; 2) Baking the above-mentioned PET short fibers; 3) Mixing the inorganic filler and dispersant to make white pulp; 4) Mixing epoxy resin, curing agent, curing accelerator, white pulp and PET short fibers, wherein The weight percentage of PET short fibers is controlled at 9-20% to make an epoxy resin pre-curing system; 5) inject the epoxy resin pre-curing system into a mold coated with a release agent; 6) put the treated mold into In the oven, solidify, and after completion, take it out, cool it, and take it off; the invention prepares an insulating cylinder that meets the requirements of a cast-type dry-type transformer with a simple process, and has excellent mechanical properties at the same time as low cost and low weight. Electrical performance and thermal conductivity, etc., and energy saving and environmental protection.

Description

technical field [0001] The invention relates to the technical field of insulating materials for cast dry-type transformers, in particular to a method for preparing an epoxy PET insulating cylinder suitable for cast dry-type transformers. Background technique [0002] Dry-type transformers are widely used in local lighting, high-rise buildings, airports, wharf CNC machinery and equipment, etc. With the continuous development of my country's infrastructure construction, its consumption has maintained rapid growth. Dry-type transformers have excellent performance and low production and maintenance costs. At present, about 50% of transformers in my country use dry-type transformers; dry-type transformers include cast-type dry-type transformers, thin-walled dry-type transformers, etc.; [0003] However, there are still many problems in the production of insulating materials for cast dry-type transformers, such as complex processes, a large number of equipment and high investment,...

AI Technical Summary

Problems solved by technology

However, during the production process of the epoxy glass cloth insulating cylinder, it is also prone to defects such as surface wrinkles, delamination, and foaming, which seriously affect its performance.

These problems have seriously limited its development, resulting in a considerable number of customers being forced to choose glass fiber reinforced epoxy resin insulation cylinders. Based on this, a preparation method of epoxy glass cloth insulation cylinders CNCN107973925A has been proposed in the prior art. However, this patent Although it solves the problems of surface wrinkles, delamination, and foaming during the production process, on the one hand, the insulating cylinder produced by it cannot be applied to other dry-type transformers such as cast-type dry-type transformers. The thin-walled type gives it the ability to The mass per unit volume or area can be heavier. When it is applied to cast dry-type transformers, due to the need for insulating materials with a thicker overall thickness (that is, good overall compressive strength), the heavy mass insulating cylinder per unit volume or area is obviously It is not suitable, and it is also not conducive to construction and maintenance. Moreover, this process is reinforced with glass cloth, which not only increases the winding process, but also increases the preparation cost.

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