The paper presents a concise introduction to the special features and the constraction of nonmetallic expansion joints as well as problems met in their application, at the same time highlighting their appliance in waste heat boilers of combined cycles, designed by the author s company.

In this paper,the author introduced the composition and principle of a blast furnace gas combined cycle generation system,gained the interrelated types and features of major manufacturers in the world according to the developmental history of combined cycle generating sets,through comprehensive analysis and a great deal of investigations.