APPARATUS AND METHOD FOR PREVENTING OXIDATION OF SLAB IN TWIN ROLL STRIP CASTER

摘要

PURPOSE: An apparatus and a method for preventing oxidation of slab in twin roll strip caster are provided to manufacture an invar alloy strip having superior surface quality by preventing inner matrix oxidation and grain boundary oxidation adversely affecting surface quality deterioration of slab and reduction of actual yield. CONSTITUTION: In a twin roll strip caster(100) comprising a pair of casting rolls(1a), edge dams(2), a meniscus shield, a gas knife and a coiler(50) so as to cast an invar alloy (Fe-Ni) strip, the apparatus(200) for preventing high temperature oxidation of slab in the twin roll strip caster comprises a shielding chamber(10) installed in a loop pit to an inner space (P) of sealed atmosphere for shielding contact of the slab with an external air from roll nip of the casting rolls to an entry pinch roll(41) of water cooling machine(40); injection nozzles(20) at least one or more of which are arranged at left and right sides of the slab along a slab proceeding line to cool the slab by injecting an inert gas onto the surface of cast slab as it is coming out of the nip roll of the casting rolls; and an instrumentation part(30) comprising a sampler(31) for sampling gas in the inner space to control an amount of gas supplied to the side of the injection nozzles by analyzing constituents of an atmospheric gas filled in the shielding chamber, and a thermometer(32) for measuring temperature of the slab threaded inside the shielding chamber.