LF treatment method for producing low-carbon low-silicon low-manganese steel

Abstract

The invention relates to the field of medium and thin slab continuous casting, and particularly relates to an LF treatment method for producing low-carbon low-silicon low-manganese steel, which comprises melted iron pretreatment and converter smelting, and is characterized by directly entering an LF furnace for refining after tapping of converter smelting, upgrading molten steel in the LF furnace through persistent argon blowing decarburization and then directly beginning continuous casting. Compared with the prior art, the method has the benefits of lowering the cost for producing the steel; compared with an RH-LF duplex process, the production cost is lowered by 37.5 yuan / ton; and compared with an RH straight-up manner, the number of production tanks is increased to 12 from 7 every cast, and the impurity removal defect rate of the steel plate is reduced; and therefore, the eddying flow phenomenon when a medium and thin slab casting machine is used for producing the steel is reduced.

Description

Technical field [0001] The invention relates to the field of continuous casting of medium and thin slabs, in particular to an LF treatment method for producing low carbon, low silicon and low manganese steel. Background technique [0002] At present, the composition requirements of low-carbon, low-silicon and low-manganese medium and thin slab steel grades are: carbon ≤0.04%, silicon ≤0.05%, and manganese ≤0.25%. When the medium-thin slab continuous caster produces this type of steel, the general process is: molten iron inversion station-molten iron pretreatment-converter smelting-RH furnace refining-continuous casting (this is the RH straight-up method) or the use of molten iron inversion Station-hot metal pretreatment-converter smelting-molten steel slagging-RH furnace refining-LF furnace refining-continuous casting (this is the RH-LF duplex method). The former process is prone to flocculation during continuous casting and casting. The inclusion defect rate is high; the latter...

AI Technical Summary

Problems solved by technology

When the medium and thin slab continuous casting machine produces this kind of steel, the generally adopted technological process is: molten iron pouring station - molten iron pretreatment - converter smelting - RH furnace refining - continuous casting (this is the RH direct method) or using molten iron pouring Station - molten iron pretreatment - converter smelting - molten steel slag removal - RH furnace refining - LF furnace refining - continuous casting (this is the RH-LF duplex method), the former process is prone to flocculation during continuous casting, steel plate The rate of inclusion defects is high; the cost of the latter process is relatively high, and the product market competitiveness is poor