Distinguish hot and cold rolled steel (27/07/2010) To distinguish hot and cold rolled steel, we should refer to the production process at the input thep.Tu iron ore, scrap until output is the product thep.Hay see figure below illustrates the steel manufacturing process:
Phase 1: Handling of ore. In this phase the inputs such as pellets (Pellet), iron ore (Iron ore), sinter, and additives such as coke (coke), limestone (lime stone) is put into the oven baked (Blast furnace). If the scrap is heated to a certain temperature 1 to make the molten metal flow (hot metal)
Phase 2: Create molten steel flow. Stream of molten metal is formed from phase 1, is leading to basic oven (Basic oxygen furnace), or EAF (Electric Arc Furnace). At this point, the hot metal handling, separation of impurities and create a correlation between the chemical composition hoc.La basis for the decision to create the kind of cool steel products, steel grade nao.Vi example batch of steel will be used for the SD390 rebar rolling components of school will be adjusted immediately at this stage to produce steel grades SD390.
Phase 3: Casting supplies. Field after the metal out of phase 2 is given to:-Steel Castings: Casting of other products. Lourdes-embryonic: From this furnace will cast out 3 types of embryos: Embryos bar (Billet) is the cross-section billet 100x100, 125x125, 150x150 6-9-12 m long. Often used for rolling wire rod, rebar. Billet slab (Slab) casts a kind commonly used for rolling the hot-rolled coils, hot rolled steel, cold rolled steel or steel billets Bloom hinh.Co type embryos can be used as a substitute for billet and ingot slabs. After the embryo can be molded to finish in two states: Status heating and cooling status. Status hot (hot direct rolling) this state to maintain embryos in a high temperature after the formation from embryonic to put straight into the rolling process products. Cold state of embryos to transfer to other plants and will be heated again (reheating furnace) in which plants to put into the process of rolling products.
Stage 4: Personnel embryos were put into the rolling mills for steel products. Embryos in steel plants (Section mill) for steel products rolled out as follows: Rail (steel rails); Sheet pile (Steel Casting) Shape (steel types); Bar (steel bar construction ). -Putting embryos in steel mills (mill rode wire) to coil rolling out sleek build. -Take into plant embryos plate (Plate mill) to staff the cast plate (Plate). -Putting embryos in hot strip mill (Hot Strip Mill), embryos will be rolled out hot rolled coil (HRC Hot-roll coil). Either cut steel plate (roll out and cut right warehouse-packaged goods Baotou). In the process of rolling out of hot rolled steel coils are high temperature (eg 780oC) if you like rolling out of cold rolled steel (Cold roll coil-CRC), the steel coils to cool it down to the appropriate temperature (eg 480oc) and continue to reduce staff day.Nhu that, even at this stage to produce cold rolled steel coil and this nong.Hien, re-rolling mills in Vietnam are using hot rolled steel billets (1.75 to 5.0 mm) and then put into the furnace up to the appropriate temperature (eg 480oC) to reduce the thickness rolling out cold-rolled steel from steel plants after rolling the hot rolled steel HRC can take straight to the welded pipe mill (welded pipe mill). -Putting in the steel mill ingot casting tube (Seemless pipe mill) to produce steel seamless pipe. On this, the manufacturing process of this product thep.Nhu we can understand cold rolled steel, hot rolled production like nao.Sau here we can see a number of pictures to be able to distinguish cold rolled steel and hot rolled steel.