METHOD AND APPARATUS OF HOT PRESS FORMING LINE

摘要

PURPOSE: Hot pressing method and device are provided to prevent the oxidizing of the surface of a steel plate and decarburization in hot pressing. CONSTITUTION: A hot pressing method comprises next steps. A plate-shaped material is put into a furnace(1). The material is heated at a temperature of over 700°C in the furnace. In a state nitrogen is filled in the heated material, HRX gas consisting of LNG and air is supplied to the heated material to prevent the generation of oxidized scales and decarburization. The heated material is discharged to the outside of the furnace. The discharged material is formed by press. Nitrogen and HDX gas are additionally supplied to the furnace. HRX gas consists of CO of 20~28%, H2 of 30~40%, CH of 0.1~1%, and N2 of 40~45%.