750kV变压器套管瓷套的试生产

Trial Produce of Thimble Porcelain Sheath Used in 750 kV Transformer

输变线路向特高压方向发展,这是电力发展的一种趋势。电压等级越高,瓷套的体积越大,重量越重,制造难度越大。制造750kV瓷套的主要技术问题是放尺率的选定、下孔变形超标、干燥掉伞、烧成开裂、研磨工装的设计和粘接时形位公差的控制。根据瓷套分节后外径的大小情况,选择不同的放尺率,同一节瓷套上、下主体也可选择不同的放尺率,以保证上、下节瓷套接口尺寸的配合,为下主体增加工艺法兰并选择适当的工艺法兰尺寸,可有效解决瓷套下孔变形;干燥和烧成工艺的局部调整,可使干燥和烧成合格率达到90%以上,研磨和粘接工装的改进可有效控制瓷套的形位公差。

Super high voltage transport line is the trend of electric power development. More higher voltage line needs more larger porcelain thimble, and there are more difficulty in making larger porcelain thimble. Several main technic issues such as expand ratio, below bore distortion, umbrella falling in dryness,craze in burnning are very important. After a series of experiments, qualification ratio come to more than 90%.