In order to study the effect of gas temperature variation on cooling stave,temperature,stress and displacement distributions of cooling stave were analyzed respectively when gas temperature inside blast furnace increases from 1000 to 1600℃.The results show that the temperature field on cold side is under control of cooling pipes and hardly changes when gas temperature increases.The temperature gradient and change rate with time near hot sides are greater than those in other regions and the later can reach 100℃/s.The stress intensity near middle area of hot surface is up to 400MPa and that's why there are lots of cracks at this place.The edge of stave is bent to cold side and middle regions between fixed bolts and pin moves to hot side.The displacement around fixed pin is smaller but larger on the edge and the maximum is located on hot side of top surface.The maximum displacement in z direction is about 4mm and 3mm in y direction.If the expansion coefficient of packing layer is 1/4,the thickness of packing layer between the cooling staves is 32mm and 24mm between sides up and down.
