Kayan aikin narkewa
Rushewa ɗaya ne daga cikin hanyoyin samar da simintin gyare-gyare.Tsarin pyrometallurgical wanda aka sanya kayan ƙarfe da sauran kayan taimako a cikin tanderun dumama don narkewa da quenching da tempering, da wasu canje-canje na jiki da na sinadarai suna faruwa a cikin kayan da ke cikin tanderun a matsanancin zafin jiki (1300 ~ 1600K), don samarwa. danyen karfe ko karafa da kuma karafa.Bugu da ƙari, mai da hankali, calcine, sinter, da dai sauransu, wani lokacin ya zama dole don ƙara juzu'i don sauƙaƙe cajin don narkewa da raguwa don wasu halayen.Bugu da ƙari, don samar da zafin jiki mai mahimmanci, sau da yawa ya zama dole don ƙara man fetur don konewa da aika iska ko iskar oxygen wadata.Za'a iya raba ɗanyen ƙarfe ko ƙarfin ƙarfe saboda ƙaramar solubility na juna tare da narkakkar slag da bambancin yawa zuwa yadudduka biyu.Abubuwan da aka tattara sun haɗa da matte da rawaya slag, waɗanda dole ne a bi da su ta hanyar juyawa ko wasu hanyoyin samun ƙarfe.
