METHOD AND PLANT FOR MANUFACTURING ELECTROTECHNICAL ARTICLES

摘要

The invention relates to methods and plants for manufacturing electrotechnical articles. The method comprises heating a lacquer and degassing the same, placing the article under vacuum, impregnating the article with the lacquer and drying it using a cyclic high-speed vacuum effect while reducing the vacuum to atmospheric pressure. When drying the article, a pulsed vacuum effect is applied after having previously heated the article to a temperature at least equal to that of the saturated vapors of a solvent at a corresponding pressure, hot air at a temperature not exceeding 120°C being blown through at the end of each cycle. The heating of the lacquer and the impregnation of the article are carried out at a temperature not exceeding 50°C and at a pressure of a least 13 kPa. The plant includes heatable vacuum apparatuses for preparing the lacquer, impregnating the articles with the lacquer, drying said articles and carrying out polymerization, which are connected via a quick-action valve by a system of vacuum ducts with a plenum and the atmosphere. A unit for heating the air is connected in a closed circuit by ducts with a drying apparatus, a heat exchanger-regenerator and a heat exchanger-condenser that is also mounted after the pump connected with the plenum. The invention increases production quality and improves the characteristics of the plant in terms of ecology and fire and explosion risks.