The in-line examination and statistics on casting process for 220 ~ 320 mm x 1 800 ~ 2 700 mm wide-thick slab of 0.07% ~0

18% C steel have been carried out for one year at steel work to study the effect of process parameters including casting rate (0.65 ~ 1. 2 m/min)

liquid superheating extent (13-35 ℃)

mold inlet water temperature (27 -35°C) and mold liquid level (775 -810 mm) on heat flux of mold copper plate during casting process of steel grades containing different C%. Results show that with casting 220 mm slab with increasing casting rate the mold heat flux increases

but as casting rate more than 1. 05 m/min

the heat flux doesn't increase again； for the steel grades with peritectic reaction

with increasing liquid superheating extent the heat flux of wide and narrow face o£ slab increases

but with increasing inlet water temperature the heat flux decreases ； due to the effect of peritectic phase transformation

during casting 0.13% C steel the mold heat flux is lowest.