《学生Manufacturingprocessforiron&steel》由会员分享，可在线阅读，更多相关《学生Manufacturingprocessforiron&steel（62页珍藏版）》请在金锄头文库上搜索。
1、Manufacturing process for iron & steel唐海燕刘青Ore Based PScrap Based PContentsSecondary RefiningSteel makingIron makingCoal and CokingIron Ore and Its PretreatmentContinuous casting Iron Ore and Its ClassificationNatural elements or compounds in earth crust are called mineralsMinerals which can extract
2、 metal or other products from under modern ecomonic and technological conditions on the industrial scale are called oreMinerals containing iron and used to make iron are called iron Magnetite, magnetic iron ore, Fe3O4Hematite, red iron ore, Fe2O3Limonite, brown iron ore, Fe2O3H2OSiderite, spathic ir
3、on ore, FeCO3Other ferrous mineralsManganese oresIron silicatesTitanium ironstoneMelting losses and dusts containing Pretreatment of oresLow-grade ore: ore dressing separates mineral containing iron and gangue. 30 35 % Fe 60 65%High-grade ore: crushing screening proper sizeFiner ores and ultra-fine
4、ores : sintering or Sinteringa mixture of wetted fine ore together with coke breeze and fluxes like limestone, burnt lime, olivine or dolomite is applied to a rotary grate（篦子，炉栏）, the sintering belt烧结料层, where it is ignited from above. The carbon content of the mixture burns with the aid of the air
5、which is sucked through the grate and the mixture, this causing the ore grains to bake together. While traveling on the sintering belt, the total layer is from top to pelletizingDuring pelletizing, ultrafine ores and concentrates of grain sizes far less than 1 mm are formed into small nodules of abo
6、ut 10 to 15mm.The ore mixture is wetted and a binding agent added. Then “green pellets” are formed in rotating drums or rotary feed tables. These green pellets are dried and burnt at temperatures of more than 1,000. This can be done in a shaft furnace, rotary kiln or on a traveling grate.Compared wi
7、th lump ores, pellets have a narrow size range, constant quality and good permeability during reduction. Furthermore, pellets are well suited for transport and ComparisonCompared with sintered ore, pellets have a higher iron and a lower gangue-content, and pelletizing is suitable for treating the ve
8、ry fineore that will predominate in the future Coal and coking Fuel is the basic material for BF smelting Coke is essential fuel due to its special features Heavy fuel,coal,natural gas are necessary supplementary Process of coke:coke washing,coke making up,coking,production Cokes function coke serve
9、s as the source of carbon the heat source for heating and melting the charged materials a high carbon content low ash and sulfur contents have an appropriate porosity as well as good strength to ensure that it gives good reactivity and does not pulverize to choke the gas flow in the BF even at high
10、temperaturesRfurnace bodys composition the shaft, which tapers outward from the topthe belly, which is a straight cylinder the bosh, which tapers inward toward its bottom and is located under the belly the hearth, at the bottom of the furnace. belt conveyors for transporting raw materials to the fur
11、nace tophoppers for temporarily storing these raw materials a bell-type or bell-less-type device for charging the raw materials into the furnace with appropriate distribution in the radial directionhot stoves for heating the blastblowers for feeding the blastequipment for dust removal, and recoverin
12、g and storing the gas from the furnace top BFs auxiliary Classification of steel按冶炼方法，化学成分和用途进行分类。(一)按冶炼方法分类按冶炼设备: 转炉钢，电炉钢和平炉钢/Martin steel。大量生产的碳素钢和普通低合金钢大多是转炉钢和平炉钢。合金钢多数是电炉钢。按脱氧程度和浇注制度的不同，碳素钢又可分为 镇静钢/ killed steel、沸腾钢 /boiling steel和半镇静钢 /semi-killed steel。镇静钢:完全脱氧钢，(用锰、硅、铝脱氧)，钢液在锭模中平静凝固。Si:0.17一0
13、.37%，Mn0.8%沸腾钢是几乎不脱氧的钢(用锰脱氧)，钢水浇入锭模后在凝固前会产生沸腾。沸腾钢一般含C:0.05一0.27%，Mn:0.25一0.70%，Si0.03% 半镇静钢的脱氧程度，钢的质量，成材率和生产费用介于镇静钢和沸腾钢之间。一般C:0.1一0.35%, Si 0.06一0.08%，Mn:0.3一1.5%。（二）按化学成分分为 碳素钢/ carbon steel、合金钢/alloy steel碳钢按含碳量: low carbon steel (C 0.25 )medium carbon steel (C 0.25一0.6%)high carbon steel (C 0.6%)
14、根据本身含硫、磷量的多少：plain carbon steel (S10)。按硫、磷含量: 质量钢(S、P0.04%)，高级质量钢(S0.030%，P0.035%)特级质量钢(S、P0.025%)。（三）按用途钢分为 结构钢、工具钢和特殊性能钢Structural steel：建造用钢和机械用钢。前者用于建造锅炉、船舶、桥梁、厂房等建筑，后者用于制造机器和机械零件。结构钢一般是低、中碳钢和低、中合金钢。Tool steel： 刃具钢、量具钢和模具钢，工具钢多属于中、高碳钢和中、高合金钢Special steel： 是具有特殊的物理或化学性能的钢，如耐酸钢、耐热钢、不锈钢、耐磨钢、磁钢等。多属于中、高合金钢。Expression of steel grade钢的牌号简称钢号/ steel grade ，是对每一种具体钢产品所取的名称，是人们了解钢的一种共同语言。我国的钢号表示方法，根据国家标准 钢铁产品牌号表示方法（GB221-79）中规定，采用汉语拼音字
