(Session 9A)Development of Hot-Rolled Extra Thick Steel Coil with Excellent Toughness and Earthquake-proof Properties

摘要

China Steel Corporation (CSC) finished the equipment revamping of laminar cooling ability and heavy duty down coiling of #1HSM in 2004 to develop hot rolled coil products of extra thick steels. When the techniques of low carbon equivalent design, heavy duty down coiling, precise process temperature control, precise laminar cooling, optimum cooling pattern, heavy reduction in the finishing mill, and low temperature rolling were applied to meet the quality requirements, hot rolled extra thick steel coils with good weldability, good coil shape, suitable tensile properties, uniform microstructure throughout the thickness direction, and excellent toughness have been produced. In 2009, CSC successfully commercialized high strength structural steels with 16-25mm thickness, which were manufactured into spiral pipes used for projects of public construction, such as pipe piles for boardwalks and expressways under the sea. In 2010, the steels of low yield ratio, narrow range yield stress and excellent toughness were used for earthquake-proof construction.