Changlong foundry company limited located in Hebei prov, p. R. China. Is a special works in specializing in ductile iron(di) casting and precision steel(ps) casting. Its fixed assets is 50 million Chinese rmb yuan. It covers 4 ha area. She has 280 staffs and workers including 20 engineers and experts. The producing of di casting used the sand casting process. She has one set of horizontal parting automatic molding line, one resin sand molding line. One set of ring molding line,24 sets of molding machine,8 sets of core auto-shooter machines,6 sets of electric furnace(0.5mt) and 2 sets of cupola(5mt) for duplexing smelting etc facilities, we can supply many kinds of high quality di castings. The annual out-put of casting is 15000 MT. The producing of PS castings used the lost-wax casting process, the workshop is equipped with mixing-wax machine, auto injection-wax machine, intermediate-frequency electric induction furnace, roaster etc advanced producing equipment. We could produce