The role and performance stemming: blast furnace to have oral stemming performance. Shandong plasticity and cohesiveness better water cannons mud, easy to squeeze and fill voids and cracks. Porosity appropriate, to facilitate the discharge of water when dry. Hebei hot water volume shrinkage stemming, in order to avoid cracks. Good sintering properties have water cannons mud, high strength, resistance to erosion and corrosion. Stemming characteristics: good volume stability at high temperatures. Tianjin small volume change under high temperature water cannons mud, easy to crack. Good opening performance, easy opening operation. Good thermal shock resistance. Since the closure work assignments and job openings, stemming drastic temperature changes, so the requirements stemming resistance to thermal shock performance is better.