Premature Failure of Copper Staves and Applied Results for New Designed Staves

In a blast furnace employing a copper stave as a cooling system, premature stave wear is experienced in many steel mills. To confirm this failure mechanism, an online ultrasonic thickness measuring device was installed in the Pohang 4 blast furnace from blow-in to acquire data. Through this, the refractory damage in hot face and real-time wear data were obtained, and the correlation with the operational factors was analyzed. Through the CFD simulation, the effect of temperature due to the refractory was confirmed, and the possibility of acceleration of the copper body was confirmed in the absence of the refractory in hot face. To improve the life of the entire refractory as well as the stave body, a refractory stress test was conducted in the laboratory, and a stable groove structure was derived using the structure program DEFORM using the data obtained from cold tests. The new designed long-life copper stave was applied to the Pohang 4 blast furnace in November 2015, and it has been proved that the life of the stave has been significantly improved since wear has not been measured until now.