PURPOSE: In steel slab insertion into a heating furnace for heat rolling, provision is made such that a position of skid mark by a fixed skid in the furnace may appear at a defined space from the leading edge of the plate. This effectively prevents defects caused by skid mark in rolling operation.
CONSTITUTION: A steel slab is heated to a rolling temperature in a walking beam type heating furnace. A position to a fixed skid closest to the slab edge is calculated from a thickness, width and length of a slab, an aimed thickness and width of rolled plate, and a purposed distance from the leading edge of rolled steel plate to a first skid mark by the fixed skid. The calculated value is used to define the position of slab insertion into the furnace. At the same time, the distance between the leading edge of rolled steel plate and the first skid mark is defined based on the purposed length such that the skid mark may not engage with any one of stands while passing through finishing rolls.
TOGASHI NOBUYUKI