On the afternoon of March 3, 2019, China Machinery Industry Federation organized 12 new types of 1000 kV AC, ±800 kV, ±500 kV DC rod suspension composite insulators independently developed by Nanjing Electric Insulator Co., Ltd. in Nanjing. National product appraisal meeting. Appraisal by experts, the comprehensive technical performance of the product has reached the international advanced level of similar products.

National Energy Administration, Ministry of Industry and Information Technology, China Machinery Industry Association, State Grid Corporation of China, China Southern Power Grid Corporation, China Electric Power Research Institute, National Insulator Lightning Arrester Quality Supervision and Inspection Center, Power Planning and Design Institute, China Southern Power Grid Research Institute, Jiangsu Electric Power Research Institute, etc. The leaders and experts of the unit attended the meeting. 17 experts formed an appraisal committee. The appraisal committee listens to reports on the company's product development summary, testing, technical and economic analysis, etc., reviews the appraisal data, and some experts inspect the production site in advance and conduct spot checks on the spot. After inquiries and discussions at the meeting, the Appraisal Committee believes that the 12 products technically appraised DC ±800 kV, ±500 kV, and AC 1000 kV rod-shaped suspension composite insulators have reasonable shed design and excellent electrical properties; higher mechanical strength, low dispersion; the comprehensive technical performance of the product reaches the international advanced level of similar products, and it is agreed to pass the product technical appraisal.