连铸英文介绍.pdf

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1、Continuous Casting of SteelSince steel was first introduced in a liquid state over 200 years ago, ithas been almost invariably the practice to cast it into rectangular blocksby ingot casting, from which the desired finished shape is obtained bysubsequent hot or cold working. These blocks or ingots w

2、ere originallyvery small in weight, but as the output of steelmaking increased, so hasthe weight so 15 ton or 20 ton ingots are now common practice. Theseingots are rolled in primary mills to produce blooms or slabs whichsubsequently receive further processing.This method of ingot casting is charact

3、erized by the following.(1)A large amount of capital is invested in moulds, bottom plates, andlocomotives.(2)Considerable capital is also invested in buildings and cranesneeded for stripping the ingots and resetting the moulds on thecasting cars, while soaking pits and preheating furnaces arenecessa

4、ry to prepare the ingots for rolling, and a primary mill toroll them.(3)Ingots contain segregation, which is a disadvantage in all steels andneeds “hot tops” for certain qualities, with a consequent high lossas scrap after rolling in the primary mills. The larger the ingot, themore intense the segre

5、gation.(4)Each ingot needs a discard to be removed at top and bottom afterprimary rolling.These requirements have turned the thoughts of steel makers to thepossibility of casting molten steel directly slabs, blooms or billets thuseliminating much of the capital and working costs outlined above, as w

6、ellas minimizing the loss of yield and the segregation in the products.Continuous casting of steel was developed in Europe in the mid 1950sand has grown rapidly till the present world capacity is over 1000 milliontons per annum, representing about 89.7 percent of the total tonnage ofsteel.The first

7、continuous casting machines for steel were alignedvertically. It involved pouring the metal from a height of over 13 metersabove ground level, with the cast section of metal descending verticallyand being progressively water cooled (Fig. 11-1). Efforts to reducebuilding-height first led to continuou

8、s-casting systems in which moltenmetal passed into a vertical mould and solidified completely before beingbent and later to the bow-type installation which has a curved mould andis the system most used today.In a typical plant, deoxidized steel from an electric furnace is run intoa ladle, transporte

9、d to the casting bay and brought to rest above theconcast machine. A stopper rod or a slide gate is used to control the flowof steel into a tundish reservoir. Once a predetermined steel level isattained in the tundish, nozzles are opened and the molten steel feeds theopen-ended mould set in a frame

10、with internal water-cooling. At thestart-up, a dummy bar, constructed of chain links, is fitted into the mouldbottom and rests between the arc formed by the machine roller guides.The molten in the mould meets the dummy bar and freezes to it and at acertain level of steel in the mould two operations

11、are immediatelyinitiated; the mould unit begins to reciprocate in a vertical direction andthe dummy bar is withdrawn through and down the machine. At thehorizontal plane it is supported by a series of rollers which are groupedinto segments for operation and maintenance and are cooled down bywater sp

12、raying.At the exit of the straightening unit a roll is lowered which separatesthe dummy bar from the length of cast steel. The dummy bar is eitherlifted to one side of the machine or hoisted on to the ramp above themachine. The strand of cast metal continues traveling along the dischargerollers to a

13、 gas torch cut-off station. At predetermined dimensions thistorch will automatically cut the strand to required lengths. Once thestart-up complete the Concast machine continues to cast sections inaccordance with the volume of metal fed from the steel furnaces.The end products of continuous casting p

14、lants are square sectionbillets (up to 250mm*250mm), and slabs which are about 300mm thickby 2500mm wide. Other shapes are also produced, including round barsand octagonal sections.Since the 1960s, continuous casting has steadily displaced ingotcasting. The types of continuous casting machines, thei

15、r listing likewisereflecting the historical development of this technique, are: vertical,bending and straightening, circular bow, oval bow. The evolution fromone form to the next has been accompanied by a considerable reduction inoverall height. Nowadays, there are further on going processdevelopmen

16、ts in the continuous casting of steel, these include: Horizontalcontinuous casting with stationary mould and continuous casting withmoving belt or rotating rolls (double rollers), etc.In brief, the reasons for continuous-casting systems are:(1)Lower investment outlay compared with that for a bloomin

17、g train;(2)More productivity than with conventional ingot-casting;(3)High degree of consistency of steel composition along the wholelength of the strand; better core quality, especially with flat strands;high inherent surface quality, leading to savings on an otherwiseexpensive surfacing process;(4)

18、High degree of automation;(5)Friendlier to the environment.生词表continuous casting连铸invariablyrectangularblockingot castingsubsequentcold workingprimary millbloomslabcapitalbottom platelocomotivestrip不变地，总是矩形的，成直角的毛坯，粗坯铸锭，模铸锭随后的，后来的冷加工初轧厂大（初轧）方坯（大，初轧）板坯资金底板机车，火车头剥，剥去resetsoaking pit重放，重新安排均热炉preheatin

19、g furnace预热炉segregationdiscarddischarge rollersoutlineyieldannumstrandbow-typeinstallationcurvecasting baystopper rodslide gatechain linkstundishmould setdummy barrollerinitiate偏析作用丢弃，抛弃卸料辊道辊子略述产量，收益年，岁铸坯弓形的，弧形的（整套）装置备，设备施弯，使弯曲连铸跨棒塞滑动水口链环中间包，中间罐全套锭模，整套锭模引锭杆辊子开始，发起reciprocatewithdrawhorizontalfreezes

20、egmentstraightenstraightening unithoistrampcut-off stationpredeterminein accordance withdimensionoctagonaldisplacelikewiseovalevolutionaccompanystationarysequenceimpetus（使）往复（运动），来回抽出，拉动水平的凝固，凝结弧形，扇形体（使）弄直，伸直矫直装置升起，吊起斜面，斜台切割站预定，预先确定根据，按照尺寸，尺度八边形的，八角形的取代，置换同样地，照样地椭圆的发展，演变伴随，陪伴固定的顺序，次序推动力，促进adoptionou

21、tlayconventionalblooming trainproductivityconsistencyinherentotherwisesurfacingTrue or False采用花费，指出传统的，常规的初轧机组生产力，生产率一致性固有的，内在的其他方面的表面加工，表面处理1. Since steel was first produced in a liquid state over 200 years ago,it has been almost invariably the practice to cast it into rectangularblocks by ingot ca

22、sting, from which the desired finished shape isobtained by subsequent hot or cold working.2. This method of continuous-casting is characterized by thefollowing: (1) A large amount of capital is invested in moulds,bottom plates, and locomotives; (2)3. Since the 1860s, continuous casting has steadily displaced ingotcasting.4. The reason for ingot casting systems are: (1)lower investmentoutlay compared with that for a blooming train; (2) moreproductivity than with conventional ingot-casting.5. The dummy bar is either lifted to one side of the machine or hostedon to the ramp above the machine.