After our repeated analysis and researching on the open-die forging and closed die forging,we ultimately adopted closed-die forging process,which can us a small tonnage equipment to forg the bottom of the big jar.

Analysis of “heat transfer method” hearth and “heat isolation method” ceramic cup synthetic hearth bottom;

According to the theory of heat transfer,based on the calculated temperature distribution in hearth bottom,it is clear that all the brick layers in hearth bottom can not be considered as a whole one for different structures result in different temperature distribution though total heat resistance is the same.

The mathematical model of heat transfer at hearth bottom was established.

The location and shape of hearth and bottom erosion line of blast furnace can be calculated by a two-dimensional model set up with the boundary element method,and the erosion station of the furnace lining is known in time.

According to condition of the existing thermal electric couples in hearth and bottom of 2 500 m~3 BF at Ma'anshan Iron & Steel Co Ltd,the hearth lining erosion online monitoring model was developed with two-point method.

The article tells of mostly the rolls of lift ram and the abuse of JOY litf ram and analyses the original sructure of the ram,at the same time puts forword suggest in reason.

Based on 2500 m 3 BF at Magang, the mathematical models for BF hearth and bottom erosion are set up with finite element method, two-point method and boundary element method and the characteristics of three methods are discussed.