Strand guidance roller frame used in continuous casting of thin steel slab from static mold, has adjustable roller spacing, to de-tune undesirable oscillations causing strand bulging

摘要

Opposite rollers (11, 31; 12, 32) in respective rows of at least one segment are spaced such that, in the unsteady state with bulges of the strand moving at the casting speed, they exhibit a phase shift with respect to a sinusoidal oscillation with wavelength (IR). This phase shift is given by : DELTA phi = ( DELTA I/IR) x 2 pi . Where: MOD( DELTA phi ) = 20 deg -90 deg , DELTA I = variation of the basic roller spacing IR, IR = Actual spacing of two rollers in a row, with Ir = VG/f, VG = casing speed, f = VG/IR = frequency of bulging in cast strand shell encasing liquid metal.