Study on the mechanical properties and service life of H13 mandrels

The microstructures and mechanical properties of H13 mandrels made by Baosteel and foreign companies were investigated in this study.Based on the comparison research,the processes were optimized,such as steelmaking,heat treatment and multiple forging processes.The quality of Baosteel mandrels was greatly improved by increasing the homogenizing of an annealing temperature and refining processes.The results of the pilot trial showed that the average number of piercing steel tubes for Baosteel mandrels was over 3000,which reached the level of imported mandrels.