Exposure to thermal state for a long time caused thermal fatigue of the refractory inside the branch pipe of pipeline 2BF of Iron and Steel Co., Ltd., and refractory material cracked and peeled due to the temperature variation during multi-times damping down, resulting in over- high temperature of the pipe body and burn-out of the wall. Due to the special structure and location of the branch pipes, refractory material inside the pipe could not be repaired during damping down period with normal maintenance methods. By adopting the ceramic welding process of the company for repair, the work efficiency was improved and the repair time was shortened and the economic benefit of the manufacturer was increased.