抄録
Gaskets have been used widely in bolted flange connections in the various plants such as chemical, petroleum refining, petrochemical, power generation and so on. The prototype of gaskets had started to use in 19 century and gaskets have improved and developed for applying severe specifications conditions in a lot of industries. The role of gaskets is to prevent leakage of inner fluid from the interfaces of connections. Asbestos gaskets have been used for a long time, however, in 1980"asbestos have replaced to non-asbestos materials in the US and Europe because asbestos have affected the human health. In Japan, the new use of asbestos gaskets was completely prohibited in 2012. In the present article, the history of gaskets is described. Recently, from the environmental regulation, the quantitative measurement of a leakage has been necessary in the bolted flange connections. Thus, the higher sealing technology is needed for satisfying the severe conditions. An overview of the recent researches and trend for designing bolted flange connections are described.
