热轧工艺外文文献翻译@中英文翻译@外文翻译

0 附件 1 热轧工艺 该轧机的主要功能是 将半成品钢重新加热到接近其熔点， 然后通过由共计 7.7 万的大功率连续滚动驱动马力发动机带动的 12 道连续轧制使钢板变得更薄更长，最后卷曲被拉长的钢板以运输到下一道工序。 热轧板卷的重量高达 30 吨至 30” 和 74” 。 将 8至 9 英寸厚 、 36 英尺长的钢板被卷成薄如 16 英寸和 1 / 2 英里长的带钢。 线圈 由两 个内径（ 眼睛 ） 为 30” 卷取机， 外径上限分别为 72”和 74” 分别与 850和 1000 磅每英寸宽（ PIW） 相对应的两个卷曲机产生。该厂为每一个 CSI 提供售后业务，以及负责运输成品 给 CSI 顾客。 大 部分材料是 由 一种自动线圈处理系统 运出轧机，通过运输线被分批运往轧机的东侧，直到它被冷却到足以载入铁路车辆。 加热炉 对于热轧工艺 至关重要的是它的步进梁加热炉，国家的最先进的设备，现在优于三老一辈（推车）式炉。 额定生产 速度为 每小时 270 吨， 效率和与板温一致的方面得到改善以使生产率能比计划提高 25。把这些钢从室温加热到 2200 2400 摄氏度需每天消耗约 10 立方米的天然气。 就像板材是按订单分配，日程安排是规定的，材料被热轧厂最西端的板厂的铁路小车和起重机分批运输。在一条轧制线上，每一 放一个轧板。因为轧板被放置在南侧加热炉的控制门的前边，所以其规模和重量是确定的。当炉内的空间足够，大型电镀机械推拉臂能够将板材移到炉内。 一旦进入内部，板材由大约 8 英尺长的炉板支撑，它是通过冷却水的 耐火涂层管 也被称为滑轨。为了降低钢板残留的冰点（滑板标记），滑板间距变化大约为熔炉内部空间的三分之二。两个独立的滑轨装置，一个固定，一个运动，轮流支撑钢板当它在炉内运动时经过一个由一对大型液压缸提供能量的机架。 该炉内部的 宽是 389”， 从地面到天花板 有 15 英尺， 142长。 它分为管制区内的温度：预热，顶面和底， 加热，顶部和底 ， 浸泡，顶和底，东和西。预热和加热区 燃烧一种天然气的混合物，同时通过在熔炉侧边的大量燃烧器预燃空气， 加热 钢板的上部和底部 到接近其排气温度。 大部分钢的预热是通过热废气经过钢板直达控制门的方式达到的。留在废气中热量 在这些大规模的热交换器 中将引入的空气预热到 1000。相反地，在加热区，钢板主要是通过加热炉壁加热。 在浸泡区， 很多小型燃烧器寻求保持各区域间温度的统一，平衡钢板冷点。耐火分隔有助于身体区分区 域，全炉内的 热电偶温度传感器 与 自动 燃烧 控制系统 相互作用 ，以保持 每个区域的目标温度。 复杂的计算机 模型计算出目标粗轧机出口温度，以获得一个炉排放（ 排气 ）的目标温度。 在连续的基础上通过炉内的每片钢板的厚度来估计剖面温度，计算机帮助操作者选择产品等级和能 最大限度地 将钢板加热到尽可能接近目标温度的生产区设定点。 轧制过程开始后， 当钢板离开粗轧机时它的温度会反馈给熔炉，更新计算机模型并通知加热器达到温度的均匀性。 1 当板坯到达熔炉尽头的卸载门，并且该计算机已经确定该钢板已经被充分加热，门打开了，大量的 提取 手臂 到达钢板的的下方，把它举起使之远离滑轨的支持，并把它拉出熔炉。东部和西部的提取器能够一次独立移除 两控钢板，同时提取较长的钢板。具有强热的钢板被放置在滚转机上被带到粗加工工序。 除 鳞 在退出加热炉之后，钢板经过一个除鳞单元， 外壳采用了 两对 喷雾头， 能够用 1500psi的压力 冲击具有强热的钢板 以消除 1/8 英尺厚的在富含氧气的加热炉内在钢板表面形成的氧化铁层。 除垢后不久，一个（相对）小 2-hi 轧机称为 能 减少板坯大约 1 英寸的厚度 ,来打破遗钢板上遗留下来的鳞片。在进入下一个工序前，扫除喷雾器 将附着在钢板表面的松动的鳞片进行清理。转移条多在粗轧过程中除鳞两次，前夕的第三 次或是最后一次轧制操作，以消除其又重新长出的鳞片在超过三分钟的时间里或以便能花费在粗轧过程中。 粗加工 粗轧机是有六个独立的粗轧机机架组成，其中最后的四个包含了体积较小的称为修边机的立式轧机。在加热炉内加热直到焕发明亮的橙黄色的钢板被轧制，一次经过一个站来生产所谓的转移条以适应精轧。 高压水射流 能清理沿途经过的钢板表面的氧化铁层或是鳞片。 在转移条从粗轧机最后一站出来的时候，其主要边缘的厚度被估计。同样的，有高温计测量板条从头到脚的剖面温度，并且一种特殊的照相机可以给板条的两端拍照。依据被轧制产品所要达到的 长度、宽度和等级，板条在离开最后一道轧制线的平均温度一般会达到1900 2100。此数据期望在精轧过程中被收集。计算机能立即计算穿过这 6 个连续轧制钢板的线程的速度和差距。 重型粗轧机有 135”宽的辊子，以便能卷曲较宽的一面（作为第一次轧制时的称谓）使钢板更宽。 一个 5000 马力的电动机驱动 直径为 42”的工作辊通过 28： 1 的齿轮来减少钢板的厚度高达 212 ”。 最后的四个轧制装置每个都包含一个修边装置来控制钢板的宽度，并将其轧制为 5到 6英尺厚，根据客户所要求的宽度、尺寸和 钢种其厚度可在此基础上上下浮动411公分。 如前所述，第三和第五粗轧机组 都有操作压力为 1500psi 的 高压除鳞 装置。这些独立的粗轧机组放置的间距逐渐变大以适应转移条在被轧制的越来越薄时的长度。 裁剪 因为一个方头段对于能正确的经过精轧工序是至关重要的，并且一个不平整的尾部会挫伤工作辊表面或是导致今后的生产过程的线程问题。几乎每一个转移条的头部和尾部末端都会通过一对具有大剪刀片的钢鼓被裁剪并增加其长度。在钢板以 100fpm 的速度在辊子上滑动时，传感器可检测其位置和速度以便测定裁剪的时间来优化裁切的数量；由于转移条的厚度超过一英寸，裁剪长度每增加一英寸将废弃 15 30 磅。 精加工 CSI 规格的热轧机包含六个能够降低转移条的厚度到根据顾客或是下一道工序的要求所得规定尺寸的精轧机组。轧制速度被设定为能允许在最后一道工序以 1500 1600的精轧温度完成最后的压下量，并达到特定的机械性能。 到现在为止，钢板被轧制成长达 200 英尺的平板。与粗轧相比，精轧是将转 移条进行连续压轧，这就意味着每一个板条将一次性通过六个轧制机组。热钢在精轧过程中被拉伸的时候是相当脆弱的，所以必须及时用一个低标准来控制为了避免将钢板被撕裂。 2 在精轧操作之前，转移条的头部和尾部将被剪裁成方形，以帮助确保正确的线程。最后两步的除鳞操作是为了清除在粗轧过程中新生成的鳞片。一旦转移条穿梭在每对连续的辊子上，在电控枢轴上的自由转动的辊子能使吸引钢板的底部来检测各个精轧机组间的张力。 按需要作出调整，以确保 钢板能够正确通过每个辊子不会 通过不正常循环 、 拉伸和折叠 过度 或撕裂。 每个辊子的位置能反馈到精 轧机 的先进自动化系统， 以及能检测辊子所受力 ，通过 X 射线测量带钢厚度 的信息，顺利工作以调整滚动速度和差距，保持稳定的带钢轧制必要的厚度尽管每一个转移条所呈现的温度不同。 层流冷却 对于冶金学上的热轧钢材性能至关重要的是卷曲温度，线圈会从这个温度冷却到室温，而这个过程的完成需要三天的时间。这 基本上相当于一个热处理退火， 在从 9 英寸厚减少到规定尺寸的过程中所施加在钢板上的压力使线圈得以冷却来缓解自己。 虽然钢是 在 重结晶过程中不断热轧，削减厚度有时超过 99， 并采取相当于钢的 不到 10 分钟的压力 ；卷取温度 由产品的冶金性能 来指定以利用操纵这些应力学性能获得最佳的机械性能。 由客户进行激光切割的售出的经过热轧工序、热轧浸泡和热轧涂油的产品是在相对较高的温度下进行连续松弛以便使从线圈上切割下来的部分能够平坦放置，即使是在残余应力已经自行消退的情况下。相反的，在相对凉爽的温度下卷曲钢板能使钢种的物理性能保持一个较高的内应力水平，限制了由自身和相互晶体之间形成的晶体和碳化物的尺寸；这些因素有助于使钢板在热轧的精轧阶段获得较高的应力。 400的冷钢在以 2700fpm 的速度经过该系统的时候需要 大量的水，所以总共有 152个由自动化系统控制的喷雾头以层流的形式来喷洒在钢板的顶部和底部。 计算机以板带行进的素的和所要达到的目标轧制温度为基础来估计需要多少水来冷却钢板，并且估计的准确性是由在后卷曲前面的高温计来确定的。为了调整所需要的喷雾器的数量，计算机可以控制喷雾器的开和闭来调整线程的长度来满足目标温度。由于要加快完成轧制过程，一旦后卷曲使钢板继续维持最终温度，当钢板被轧制时为了弥补它在运行出平台所减少的时间越来越多的喷雾器被激活。 整个连轧机泵每分钟输送高达 75000 加仑的水来冷却冷轧带钢、加热炉滑 轨、卷取单元和除鳞装置。所有的水是在除鳞系统和污泥收集系统中循环的，通过层流冷却系统，然后回到两个专门的冷却塔中的其中之一。 卷取 CSI 的热连轧机目前的配置依赖于两个卷取机 。两个卷取机之间存在细小的差异，但是两个可操作卷取机都是以一对能抓住钢板头部和尾部并在行进和返回轧机的过程中施加张力的夹送辊开始。它的头部在出入口到与卷取机相连的 30”心轴处有一个倾斜，并引导与输送带相连的驱动辊芯轴周围的气动。 一旦钢板的头部一直缠绕在心轴上，板卷开始在心轴上建立并迫使远离包装卷。一旦钢板的头部被抓住或者是摩擦力 和防止打滑的张力组织钢卷相对于心轴滑动，驱动轴会使日益增长的钢卷松开。在钢板的尾部完成最终轧制后，夹送辊继续保持后张力以防止钢卷松开；在钢板的尾部被拉出夹送辊前，驱动辊一直在运作。具有液压线圈的小车运动到板卷的下方，然后上升到支持线圈的体积，将板卷从心轴上拿走并把它放置在能运输到标记和自动打捆机程序的位置。 板卷 处理 板圈被具有液压线圈的小车从卷取机上取下放置在洞内的平台上，在这两个能来回运动的步进梁中的其中之一会将板卷放置在能被鉴定和捆扎的位置。因为产品仍然很热以至于适用于使用能在整个工厂辨别板 卷的纸质标签，一对镀锡薄铁皮采用激光刻录鉴别信息在不锈钢上，被亲切的称为牌照。在板带被应用前这些都是准确焊接在钢卷外3 部的。钢板以前是以供应商的连铸机的压力和剪切系数来区分，现在被一具有六位字母数字代码的特殊辊子条码来区分。 第二辆具有液压线圈的小车将板卷从打捆机中取出送往轧机外的旋转体中，这个旋转体能够缓慢旋转板卷 90，另一辆小车能够将板卷送往自动升降机。两个以上（高速）的线圈车和另一辆升降机能够携带板卷完成它的行程，要么送往能把它送往热轧最终工序的输送带，要么送往冷却池。总之，自动化系统采用 10 个独特的电动液压装置，每一个依赖于多个传感器来运输 90的热轧带钢产品到下一场地，在那里下一个操作将被执行。 附件 2 The Hot Rolling Process The primary function of the Hot Strip Mill is to reheat semi-finished steel slabs of steel nearly to their melting point, then roll them thinner and longer through 12 successive rolling mill stands driven by motors totaling 77,000 hp, and finally coiling up the lengthened steel sheet for transport to the next process. The Hot Mill rolls slabs weighing up to 30 tons between 30” and 74”. Steel slab 8 to 9 inches thick and up to 36feet long is rolled into strip as thin as 1/16 inches and up to a half-mile in 4 length. Coils are produced with a 30” inside diameter (eye) on one of two coilers, with outside diameter limitations of 72” and 74”, corresponding to850 and 1000 pounds-per-inch-width (PIW), respectively. The mill supplies coil for each of CSIs remaining operations, as well as a finished product for shipment directly to CSIs customers. Most material is transported out of the mill area by an automated coil handling system, though some skelp for the Pipe Mill is staged toward the east end of the mill bay until it is cool enough to load onto rail cars. Reheating Critical to the Hot Strip Mill is its walking-beam reheat furnace, state-of-the art equipment that replaced and now outperforms three older- (pusher-) style furnaces. Nominally rated to produce 270 tons-per-hour, improvements in efficiency and some sacrifice in slab temperature uniformity enable extended productionrates 25% above design. Heating this much steel from room temperature to 2200-2400 degrees Fahrenheitconsumes around 10 million cubic feet of natural gas each day. As slabs are assigned to orders, schedules are written and material is staged with rail-cars and overhead cranes in the slab yard at the west end of the Hot Strip Mill. Slabs are placed, one at a time, on a roll line. The slabs dimensions and weight are confirmed as it is positioned in front of the charge door on the south side of the furnace. When space is available in the furnace, large electro-mechanical pusher armsengage to move the slabs into the furnace. Once inside, the slabs are supported about eight feet off of the furnace floor by water-cooled, refractory-coated pipes called skids. To minimize the cold spots (skid marks) left in the slab, the skid spacing changes approximately two-thirds of the way through the furnace Two independent sets of skids, one fixed, one walking, take turns supporting the slab as it is walked through the furnace by a massive sub-frame energized by a pair of large hydraulic cylinders. The interior of the furnace is 389” wide, fifteen feet from floor to ceiling, and 142 long. It is divided into eight zones for temperature control: preheat, top-and-bottom； heating, top-and-bottom； and soak, top-and-bottom, east-and-west. The preheat and heating zones combust a mixture of natural gas and preheated combustion air with massive burners on the side walls of the furnace, both above and below the skids, to heat the slab nearly to its discharge temperature. Much of the preheating of the steel is achieved by the hot exhaust gases rushing past the slabs on the way to the recuperators above the charge door. Whatever heat is left in the exhaust gases preheats the incoming combustion air to over 1000 F in these massive heat-exchangers. Conversely, in the heating zone the steel is primarily heated by the glowing-hot furnace walls. In the soak zone, numerous smaller burners seek to maintain a uniform temperature within the zones to equilibrate any cold spots in the slabs. Refractory dividers help to physically distinguish the zones, and thermocouple temperature sensors throughout the furnace interact with the automatic burner control systems to maintain the target temperatures in each zone. Complex computer models calculate the targeted roughing mill exit temperature to obtain a furnace discharge (drop-out) aim temperature. Estimating the temperature profile through the thickness of each slab in the furnace on an ongoing basis, the computer aids the operator in selecting the production rate and zone set-points that will maximize production of steel slabs uniformly heated to as close to the target temperature as possible. After the rolling process begins, as the steel exits the roughing mill, its temperature is fed back to the furnace, updating the computer models and informing the Heater as to the temperature uniformity. 5 When the slab reaches the discharge door at the exit end of the furnace, and the computer has determined that the slab has been sufficiently heated, the door opens and massive extractor arms reach beneath the slab, lift it off of the skid supports, and draw it out of the furnace. The east and west extractors can act independently of one another to remove double-charged slabs one-at-a-time, or in conjunction to extract longer slabs. The intensely hot slab is placed on a roller table which carries it into the roughing mill. Descaling After exiting the reheat furnace, the slab passes through a descaling unit, an enclosure employing two pairs of spray headers that blast the intensely hot slab with 1,500 psi pressurized water to remove the 1/8-inch thick layer of oxidized iron that forms at the surface of the slab in the oxygen-rich atmosphere of the reheat furnace. Shortly after descaling, a (relatively) small 2-hi rolling mill called a scalebreaker reduces the slabs thickness by about one inch to break up any scale that remains. Just before the next reduction pass is taken, sweep sprays clean away any loosened scale that remains on the slab surfaces. The transfer bar will be descaled twice more during roughing, immediately prior to the third and to the last rolling operation, to remove the scale that has grown back over the three minutes or so that it spends in the roughing mill. Roughing The roughing mill is made up of six independent rolling mill stands, the last four of which incorporate small vertical rolling mills called edgers. Slabs heated in the furnace until they glow bright orange-yellow are rolled through one stand at a time to produce so-called transfer bars suitable for finish rolling. High-pressure water-jet nozzles clean the oxidized iron, or scale, from the surface along the way. As the transfer bar exits the last roughing mill stand, the thickness of the leading edge of the bar is estimated. Similarly, a pyrometer measures the temperature profile of the bar from head to tail and a special camera photographs both ends. Depending on the gauge, width, and grade of the product to be rolled, the average temperature of the bar as it exits the last roughing mill normally ranges from 1900 to 2100 Fahrenheit. This data is collected in anticipation of finish rolling. Computers immediately begin calculating the speeds and gaps for threading the six finishing mills, which will roll the steel in tandem with one another. The workhorse roughing mill has 135” wide rolls for rolling broadside (as the first roughing mill is commonly called) to make a slab wider. A 5,000 hp motor drives 42”-diameter work-rolls through 28:1 gears to reduce theslabs thickness by as much as 2-”. The last four roughing mills each incorporate edgers for width control and roll the bar from five to six inches thick incrementally down to around an inch and a quarter, depending on the customers ordered width, gauge, and steel grade. As mentioned previously, the third and fifth roughing mills each have high-pressure descaling headers operating at 1,500 psi. The individual roughing mills are spaced increasingly further apart to accommodate the lengthening of the transfer bars as they are rolled thinner and thinner. Cropping Because a square head-end is critical to properly threading the finish mills and the downcoilers, and because an uneven tail can bruise work-roll surfaces or cause threading problems for the next production process, the head- and tail-ends of nearly every transfer bar are cropped by a pair of large steel drums each with a shear- blade extending along its length. With the bar crawling along the roller table at around 100 fpm, sensors detect its position and speed in order to 6 time the crop shear drums to optimize the amount cropped； since transfer bars are over an inch thick, each extra inch of crop-length scraps another 15-30 lbs. Finishing CSIs Hot Strip Mill includes six finishing mills, which reduce the thickness of the transfer bar down to the gauge required by the customer or the next process. The rolling speed is set to allow the last stand to perform the final reduction at the finishing temperature, between 1500 to 1650F, specified to reach certain mechanical properties. By now, the steel has been rolled into a flat bar as long as 200 feet. In contrast to the roughing mills, the finishing mills roll the transfer bar in tandem, meaning each bar will be rolled through all six stands at once. The hot steel is quite fragile as it is rolled and tension between the finishing mill stands must be closely controlled at very low levels in order to avoid stretching or tearing the strip. Prior to the finish rolling operation, the head- and tail-ends of the transfer bar will be sheared to square them up, helping to ensure proper threading and tail-out. A final two-stage descaling operation is performed to clean off the scale that has grown on the bar during roughing. Once the bar is threaded between each successive pair of mills, a free-turning roll on an electro-mechanical pivot called a looper roll engages the bottom of the strip to monitor the tension between the stands. Adjustments are made as necessary to ensure the strip threads properly through each of the mills without looping up and folding over or stretching and tearing apart. The position of each roll is fed back to the finishing mills sophisticated automation system which, along with information from the load cells that monitor rolling force and from the X-ray gauge measuring final strip thickness, work to smoothly adjust the roll gaps and speeds to maintain stable rolling of strip to the necessary thickness in spite of the temperature variations present in every bar. Laminar Cooling Metallurgically critical to the properties of hot-rolled steel is the coiling temperature, as the coil will cool from this temperature to ambient over the course of three days. Essentially a heat treatment comparable to annealing, the stresses imparted to the steel during reduction from nine inches thick down to ordered gauge are given the opportunity as the coil cools to relieve themselves. Though the steel is continually recrystallizing during hot- rolling, reductions in thickness sometimes in excess of 99% and taking place in less than ten minutes stress the steel considerably； coiling temperature is specified by product metallurgists to harness and manipulate those stress levels in search of optimal mechanical properties. Product sold as hot rolled and hot rolled pickled and oiled to be laser cut by a customer is coiled at relatively high temperatures to try to relax the steel as much as possible so that parts cut from the coil will lie flat even after residual stresses have resolved themselves around the parts configuration。 Conversely, coiling at a relatively cool temperature allows physical quality steel grades to retain higher internal stress levels and limits the size of the individual crystals and of the carbides that form within and between the crystals； each of these factors contributes to higher strength levels in the finished hot-rolled strip.Cooling steel 400F as it rushes past at speeds up to 2700 fpm requirestremendous amounts of water, so a total of 152 spray headers, individually valved and controlled by the automation system, drench the steel from the top and bottom with curtains of water. The computer estimates, based on the thread speed of the strip and target finishing temperature, how much water will be needed to cool the head-end, and the accuracy of this estimate is confirmed by a pyrometer in front of the downcoilers. As adjustment to the number 7 of sprays in use is needed, the computer will turn sprays on and off to meet the targeted temperature through the length of the coil。 Since the finishing mills will accelerate once the downcoiler is threaded to continue to make finishing temperature, increasingly more sprays are activated as the steel is rolled in order to compensate for the reduced time it spends on the run-out table. Up to 75,000 gallons of water are pumped each minute throughout the Hot Strip Mill to cool finish-rolled strip, furnace skids, mill rolls, and coiler components, and to descale transfer bars. All water is recycled through a system of scale/sludge collection pits, through the laminar cooling system, and back to one of the two dedicated cooling towers. Coiling CSIs Hot Strip Mills present configuration relies on two Coilers. Minor differences exist between the two, but both operable coilers begin with a pair of pinch rolls that catch the strip head-end and establish tension across the run-out table and back to the finishing mills. The head-end is deflected by a gate down to the 30” mandrel associated with the coiler and is guided around the mandrel by pneumatically-actuated wrapper rolls linked by aprons. Once the head-end is all the way around the mandrel, laps begin to build around the mandrel, forcing aw