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为测算钢锭浇注过程中钢锭模的热应力场和裂纹趋势,建立了双因次数学计算机模型。运用数学模型首先计算了钢锭凝固过程中和脱锭之后钢锭模横截面的瞬时温度分布,其次计算了钢锭模的综合弹性—塑性热应力和形变。为了计算应力和形变,数学模型采用了通过实验测出的应力—应变关系,其数据则是在钢锭模内壁取样、在21—955℃温度范围内测定其张力和压力而取得的。为考察钢锭模裂纹趋势,将计算出的应力值与该温度下铸铁的实际破裂应力作了比较。测算目的在于弄清标准钢锭模和经改进的钢锭模何者得以减轻模重而不致增加裂纹趋势。 将数学模型运用于不同尺寸的板坯和方坯上大下小钢锭模的结果表明:减轻模重不但是可行的而且还能使热应力和裂纹趋势有某种程度的降低。在工厂进行的若干个轻型钢锭模的试验支持了数学模型计算的结果。轻型钢锭模和标准钢锭模的性能相同,从这两种钢锭模所取得的裂纹数据与数学模型测算的结果完全相符。在首次工厂实验之后又对六个上大下小钢锭模(重16～70吨)进行减重14％～20％的设计以在三座工厂中试验。最后将这六种钢锭模改为轻型设计,预计每年可节约铸铁10,000吨以上,并促进其他上大下小钢锭模和上小下大瓶口式钢锭模的设计轻型化。
In order to calculate the thermal stress field and crack tendency of ingot mold during the ingot casting process, a two-order mathematical computer model was established. The mathematical model was used to calculate the instantaneous temperature distribution of the ingot mold cross section during the ingot solidification and the ingot ingot removal. Secondly, the comprehensive elastic-plastic thermal stress and deformation of the ingot die were calculated. In order to calculate the stress and deformation, the mathematical model uses the stress-strain relationship measured experimentally. The data is obtained by sampling the inner wall of the ingot mold and measuring its tension and pressure in the temperature range of 21-955 ° C. In order to investigate the tendency of ingot mold cracks, the calculated stress values were compared with the actual rupture stresses of cast iron at this temperature. The purpose of the calculation is to find out which of the standard ingot molds and the improved ingot molds can be used to reduce the weight without increasing the tendency of cracks. The mathematical model applied to different sizes of slabs and billets on the small ingot mold results show that: to reduce the weight is not only feasible but also to thermal stress and crack tendency to some extent reduce. Testing of several light steel ingot molds at the factory supported the results of the mathematical model calculations. The performance of the light steel ingot mold is the same as that of the standard steel ingot mold, and the crack data obtained from these two ingot molds are in good agreement with the results of the mathematical model. After the first factory test, six more steel ingot molds (weighing 16-70 tons) were weight-reduced by 14% -20% to be tested in three factories. Finally, the six ingot molds into light design, is expected to save more than 10,000 tons of cast iron each year, and promote the other on the big small small ingot mold and the next small big ingot mold design lightweight.