Development and industrial application of ultra-fast cooling technology

A new-generation TMCP（NG-TMCP） with ultra fast cooling（UFC） as core technique was suggested instead of the convention- al TMCP in which some problems are to be solved. And the ultra fast cooling technology has been successfully applied to the plate rolling production in Shouqin Metal Materials Co. Ltd. Industrial trials are reported for the production of X70 pipeline steels （about 70000 t） under UFC conditions. Pipeline steels with reasonably good properties have been produced on an indus- trial scale. UFC can improve the temperature uniformity, the mechanical properties and the plate profile of X70 pipeline steel. The performance features of the trial plates can meet the standard of X70 pipeline steel. Spot test results have shown that the qualification rate of shape control, the performance and charpy impact properties for the trial plates are 95%, 97% and 98%, respectively. The impact values of X70 pipeline steel at UFC mode exceed the standard requirements of X80 pipeline steel. The productivity is enhanced because cutting quantity of head and tail of the plate is reduced. The enhancement of control ac- curacy of the red back temperatures is favorable for industrial production of X70 pipeline steel. The reduced production of the steel-making has been industrially achieved, since a new composition was designed by reducing the vanadium content to less than 0.045 wt.%.