When we make a design of steel plant, firstly type of CCM shall give full consideration combining the product process, product quality and project economic aspects. When the CCM works with electric furnace or converter, some points must be considered carefully.
Points to be considered
Multi-furnace continuous casting
In order to give full use the production capacity of the continuous casting machine, generally through multi-furnace continuous casting method to improve steel yield and reduce costs.
Orderly process connection
Casting time of the CCM and the converter should have good coordination.
CCM capacity
CCM capacity should be larger than the steelmaking furnace production capacity, generally there should be 10-20% surplus.
Proper refining equipment
The appropriate refining equipment can ensure steel liquid quality.
CCM matching rolling mill
Steel grade
Presently, the CCM may produce more than 100 kinds of steel grades. It shall choose the next processing step according to the product quality and steel grade accordingly.
Billet section
The size and shape of the billet section shall be compatible with the billet section required by the mill. Small billet CCM mainly supplies 650, 500 or 400 type mills to produce bars, profiles and wire rods. In general, 140~220mm billet is for 650 mill; 120~140mm billet is for 500/300 mill; 400 / 300 mill may input 90~120mm billet; The 160mm billet is mainly used for producing steel sections such as rails, I-beams, channel steel, etc. Slab is mainly used for thick plate mill or broad strip mill to produce medium thick plate or hot rolled strip coil.
Compression ratio
Generally speaking, the supply billet section is small, can reduce the heating times and rolling passes, and improve mill productivity and energy savings. But the section compression ratio must meet product quality as a prerequisite. The compression ratio refers to the ratio of the cross-sectional area of the cast billet to the cross-sectional area of the rolled material. In order to ensure that internal organization of the rolled material is dense, with good mechanical properties, various products apply different compression ratios. When the compression ratio is 3, it can reach the mechanical properties of common product demand; when the compression ratio reaches 4, the product has good physical properties.
Shape tolerance
For square billets, its shape is required to be regular. The deviation of the two diagonals of the section is less than 2.5~3%. The deviation of the corner of the section is 90芩2 degree. If the billet has a serious diamond shape, it may cause pile steel event, or the billet is difficult to bited into the hole pattern during rolling. For slabs, should be prevented from having a serious bulge and its max. warping value is 10mm/m.
