年产280万吨热轧带钢车间设计

1、学 号：200906040106HEBEI UNITED UNIVERSITYl 毕业设计摘要译文TRANSLATION OF GRANDUATE THESISS ABSTRACT设计题目：年产280万吨1780热轧带钢车间设计学生姓名：张志芳专业班级：09成型1班学 院：冶金与能源学院指导教师：杨海丽 教授2013年05月28日摘 要板带材生产技术水平不仅是冶金工业生产发展水平的重要标志，也反映了一个国家工业与科学技术发展的水平。建设现代化的热轧宽带钢轧机要满足现代工业对热轧板品种质量的要求。最终产品的质量取决于连铸坯的质量，传统厚度的板坯连铸工艺明显优于薄板坯连铸工艺。薄板坯连铸连轧更适于

2、生产中低档板材品种，在薄规格产品生产方面具有明显优势。为了满足高质量和高性能板材要求，采用厚板坯常规连轧生产方式更合理。本设计为年产280万吨1780热轧带钢车间设计，典型产品厚度为3.0mm。为了满足高质量和高性能板材要求，本次设计结合唐钢1700mm、宁钢1780mm、鞍钢1780mm热轧车间设计了年产280万吨的1780mm常规热轧车间。设计采用两架四辊可逆粗轧机，轧制六道次，精轧机选用六架非可逆轧机轧制六道次，通过采用CVC轧机、PC轧机和厚度自动控制(AGC)等技术相结合来控制板型和厚度，在精轧前采用无芯轴隔热屏热卷箱。本设计粗轧机组选用两架独立的可逆轧机，两架带立棍的强力四辊可逆轧

3、机，共完成6个道次粗轧，不但解决了粗轧轧制时间过长、与精轧机不匹配的问题，还能保证中间坯厚度及凸度的稳定性。精轧选用6机架连轧，前四架采用板型控制良好的CVC技术。全线采用许多新技术来保证稳定生产。产品在质量、精度等各方面居于先进水平。热轧板带机轧制连铸坯，生产厚度为1.512.0mm的带钢。板坯在加热炉中加热到1200左右，由两架粗轧机将板坯轧到30mm左右。粗轧后，由飞剪切头，进入精轧。带钢经过由六架组成的精轧机组轧制。然后，再经过层流冷却进行冷却，最后由地下卷取机卷取。最终产品可经过冷轧进行再加工。轧制前先除鳞，除鳞的方法有多种，而现代工厂只采用投资很少的高压水除鳞箱及轧机前后的高压水喷

4、头即可满足除鳞要求，其水压过去为12MPa左右，嫌低，现已采用1525MPa以上，合金钢则需更高的水压值。 考虑到缩短车间长度和粗轧时奥氏体回复再结晶程度以适应给冷轧薄板供坯的工艺需求，本次设计采用了两架独立的粗轧机，板坯在粗轧机上共轧制六道次，如果板坯厚度小，粗轧还可以分配空轧道次，同样可达到节能效果。根据产品大纲要求，生产薄规格为6.015.0mm带钢要占40%以上，为提高精轧入口温度，减少中间坯头尾温差，提高终轧温度(绝大部分要在850以上)，保证带钢应有的质量、内部组织性能，粗、精轧间采用保温设施是必要的。热卷取箱保温效果较好，一次性设备投资虽高一些，但技术成熟，设备运转可靠，生产、维

5、护费用较低，所以本设计选用它。精轧机组的布置为六机架连轧。带坯在进入精轧机之前，首先要进行测温、测厚并接着用飞剪切去头部和尾部。切头的目的是为了除去温度过低的头部以免损伤辊面，并防止“舌头”、“鱼尾”卡在机架间的导卫装置或辊道缝隙中。有时还要把轧件的后端切去，以防后端的“鱼尾”或“舌头”给卷取及其后的精整工序带来困难。现代的切头飞剪机一般装置有两对刀刃，一对为弧形刀，用以切头，这有利于减小轧机咬人时的冲击负荷也有利于咬钢和减小剪切力。飞剪设备主要用于切头、切尾、事故剪断及成品倍尺剪切，它在消除开花头子、减少头尾翘皮、倍尺优化和事故剪断等方面有着十分重要的作用。由于飞剪是在轧件运行中进行剪切的，

6、这就必须满足剪刃在水平方向上的分速度与轧件的运动速度同步的要求 。生产线上共设两处剪，即精轧入口与卷曲机前面，由于剪切过程是在轧件运动的同时完成的，故均选择飞剪。活套对产品的质量起到了积极的作用。通过活套可以调节带钢速度来保证稳定轧制。例如，若张力较低，增加活套角，增大张力，使轧制稳定。若张力较大，减小活套角，减小张力。更全面的说，为了减小张力波动，活套角应保持在一定的角度。为了在非稳定轧制时调节大的速度波动，活套角需有一个比较大的变化范围。为了保证热轧中带钢的质量和速度，可以采用同时控制活套角和张力的方法。在传统方式中，通过改变电机的速度来控制活套角，但没有张力反馈控制，这是因为在机架内部安

7、装和固定张力测量装置有一定的困难。传统的PI控制就是依据这种原理，这种控制在工业中曾被广泛应用。为了满足产品大纲的所有产品的力学性能，机械性能和金属组织，终轧后选择层流冷却方式对带钢进行冷却，层流冷却采用恒定压力的低压水进行冷却，形成柱状水流，而且有比喷射多的动能冲击在板面上，击破板面的蒸气膜，形成核沸腾，整个冷却段大约27米，分为6段控制，其中最后1段可以实现水量微调控制以满足卷取温度误差控制，冷却水量6000立方米每小时，为了方便维修，上面的喷水横梁设计成为液压缸驱动的可以开闭式。层流冷却系统的设计适用于全厚度范围，每一段的压力是通过调节喷水横梁上面的开口度来控制的，同时保持高水位水箱的水

8、在一定的范围内测喷设备，通过向带钢的表面积喷射水压约为10千克力每毫米的水来吹走钢表面的冷却水，其目的是防止带钢冷却温度的弥散，它安装在精轧机核每段冷却段的后面，高压喷水由气动控制阀门来打开或者关闭。地下式卷取机布置在热连轧机输出辊道。由于它位于辊道标高之下，所以被成为地下式卷取机。在整个连轧机组中，卷取机的工作条件最为恶劣，也是最易出故障的环节之一。为了保持连轧机组的生产节奏，本设计采用两台卷取机，两台交替使用。另外该设计附有车间平面布置图，以供参考。关键词: 半连轧工艺；步进式加热炉；热卷箱；液压AGC系统AbstractThe hot strip production technique

9、 level is not only a important marking of the metallurgy industry produce development level, but also reflects a level of the national industry and science technique.The new modern hot wide rolling mills should satisfy the request of modern industry to hot strip species quality.The quality of end pr

10、oduct is by all means decided by quality of continuous casting slab. The continuous casting slab of traditional thickness is obviously better than thin slab continuous casting and rolling. Thin slab continuous casting and rolling is suitable to produce medium low file time plank material species and

11、 have obvious advantage at the thin specification product.For satisfying the request of obtaining the high quality and high performance strip, thick slab continuous casting produce method is considered more reasonable.The 1780 is designed to produce 2.8 million tons of hot rolled strip plant design,

12、 a typical product thickness3.0mm. To meet the requirements of high quality and high performance boards, this design combines the Tangshan Iron and Steel 1700mm, Ning steel 1780mm, Anshan Iron and Steel 1780mm hot rolling workshop designed annual output of 2.8 million tons of 1780mm conventional hot

13、 rolling workshop. Design uses two four-high reversing roughing mill, rolling six times, finishing mill selected six non-reversible rolling mill six times, through the use of CVC mill, PC mill and thickness control (AGC) to control panels and other technology-based combination and thickness, in the

14、no-mandrel before finishing the heat shield coil box. In the design, the rough mills use one two-high un-reversible mill and one four-high reversible strong mill with vertical roll completing 6 pass rough.It not only solves the problem that the time of the rough rolling is too long and the Finishing

15、 mill does not match with rough mill , but also ensures stability of the middle billet thickness and the crown. The 6 stands continuous rolling is used in the finishing mill, the former three stand using good crown control of the CVC technology. All adopts many new technologies to ensure stable prod

16、uction. In quality, precision, and other aspects, the production occupied the advanced level. Hot rolling plate and strip rolling continuous casting machine, the production of 1.512.0mm thickness of the strip. Slab in the furnace heated to 1200 in about two rough slab rolling mill will be around to3

17、0mm. After roughing, the first cut by flying into the mill. After strip by six or seven units, composed of rolling mill. Then, another strip laminar cooling for cooling, and finally by the underground coiler coiler. After the final product can be re-processing of cold-rolled.Descaling before rolling

18、, in addition to scale a number of means, practice shows that investment in modern factories using only a few high-pressure water descaling boxes and rolling mill before and after the high-pressure water descaling nozzles can meet the requirements of 12MPa pressure for about the past, too low, which

19、 has been adopted by more than 15 25MPa, alloy steel pressure value should be higher.Shorten the workshop, taking into account the length and rough rolling back when the austenite recrystallization in order to adapt to the degree of cold-rolled sheet for the demand for green technology, this design

20、uses two independent roughing mill, slab in the rough rolling mill on the total six times that if the slab thickness of small, rough rolling mill can also pass the allocation of space, the same energy saving effect can be achieved.Outline based on product requirements, specifications for the product

21、ion of thin strip to be 6.0 16.0mm accounted for more than 40%, to improve the finishing inlet temperature to reduce the temperature difference between the middle of billet head, raise the finishing temperature (the vast majority to more than 850 ), strip to ensure proper quality, the internal organ

22、ization of performance, rough, finishing facilities between the use of thermal insulation is necessary. Hot-coiling me without heat, better insulation, although the high one-time investment in equipment, but the technology is mature, reliable equipment operation, production, lower maintenance costs,

23、 so the selection of its design.Finishing the layout of units to six rolling rack. With billet before entering the finishing mill, first of all to carry out temperature measurement, thickness measurement and then used to fly to the head and tail cut. The purpose of the first cut is to remove the hea

24、d temperature is too low so as not to damage the roller surface, and to prevent the "tongue", "fish" cards in the rack between the guide roller device or gap in the. Sometimes rolled piece to the back-end truncated in order to prevent the back-end of the "fish tail" or

25、"tongue" to the take-up and finishing the process difficult. First of all modern flying shear devices generally have two pairs of blades, one for the arc-shaped knife, to cut first, which is conducive to reduce the impact of mill load when bites will also help reduce the bite of steel and

26、shear stress.Flying shear equipment used mainly for cutting head, cut tail, cut and finished the accident-foot shear times, the elimination of its flowering head, head and tail to reduce the outstanding skin, fold-foot cut, such as optimization and accidents have a very important role. As the flying

27、 shear is a rolled piece cut operation, which must meet the cut edge in the horizontal direction at the speed of the rolling velocity of synchronization requirements.A total of two lines cut, that is, finishing in front of the entrance and curl machine, as a result of shear in the rolling process is

28、 completed at the same time movement, it had opted for flying shear.Live sets of the quality of products has played an active role. Through the looper can be adjusted to ensure the stability of strip undulating speed. For example, if a lower tension and increase looper angle, increasing tension, so

29、that the stability of rolling. If the tension, reducing the looper angle, reducing the tension. That a more comprehensive, in order to reduce the tension fluctuations looper angle should be maintained at a certain angle. In order to regulate non-steady rolling speed of large fluctuations in looper a

30、ngle to be have a relatively large range.Hot-rolled strip in order to ensure the quality and speed, can be used at the same time control of looper angle and tension of the method. In the traditional way, by changing the motor speed to control the looper angle, but there is no tension feedback contro

31、l, which is installed in the rack and fixed internal tension measuring devices have certain difficulties. Traditional PI control is based on this principle, such control has been widely used in industry.Products to meet the outline of the mechanical properties of all the products, mechanical propert

32、ies and metal organizations, after finishing options laminar flow cooling method for cooling of the strip, using a constant laminar cooling of the low pressure cooling water to form a cylindrical flow, but also than the kinetic energy of the impact of multijet in the plate surface, break up the stea

33、m plate membrane surface to form a nuclear boiling, the entire cooling section of about 27 meters, is divided into 6 control, which can last 1 to fine-tune control of water to meet the needs of coiling temperature error control, cooling water, 6,000 cubic meters per hour, in order to facilitate maintenance, the water above the beams designed to be driven by hydraulic cylinder-type.Laminar flow cooling system design applied to the entire thickness of the scope