宝钢电镀锡机组软熔导电辊失效的分析

宝钢电镀锡机组软熔导电辊使用寿命短,抢修频繁,一定程序上制约了机组的正常生产。我们对软熔导电辊的失效原因进行了详细分析,认定粘和磨损是导电辊失效的主要原因提出了相应的解决对策。     

宝钢电镀锡机组2#软熔导电辊粘锡失效模拟研究

粘锡是宝钢电镀锡机组 2 # 软熔导电辊失效的主要原因 ,通过模拟 2 # 软熔导电辊的工况条件 ,研究了影响导电辊粘锡失效的主要因素。结果表明 ,淬水槽水温和导电辊冷却水温是影响导电辊粘锡失效的主要因素 ,提高淬水槽水温和导电辊冷却水温 ,都促使导电辊辊面粗糙度降低 ,加剧辊面粘锡。此外提高淬水槽中的锡含量 ,也促使导电辊粘锡。采取带钢出淬水槽后加快带钢冷却和降低导电辊冷却水温等措施 ,可减轻导电辊粘锡 ,提高导电辊寿命     

电镀锡机组软熔导电辊脱锡技术研究

粘锡是电镀锡机组软熔导电辊失效的主要原因,应用化学方法脱锡是延长导电辊寿命的重要途径.开发了氢氧化钠(钾)为主要组成,并加入适量亚铅酸钠(钾)和硝酸(亚硝酸)钠配制而成脱锡剂,当脱锡剂温度为40～80℃,导电辊表面温度为40～70℃时,对粘锡导电辊具有很好的脱锡效果.粘锡导电辊脱锡后的表面粗糙度可以恢复到4.0μm以上,导电辊使用寿命提高80%,降低导电辊修复成本90%,并大幅度减少导电辊更换时间,提高电镀锡机组生产作业率.     

镀锡线光面导电辊镀层的修复技术

概述武钢冷轧厂是从联邦德国引进的设备。导电辊是该厂连续镀锡机组的专用辊子,分光面辊和麻面辊两种,用于镀锡、软熔和后处理三道工序。镀锡机组全线共有十三根导电辊,是生产镀锡薄板的关键部件。镀锡、软熔和后处理用的导电辊用途各有不同,以软熔导电辊为例,软熔段安装的两根光面辊,传导交流电压60～230伏,电流6000～12000安,承受温度200～300℃,机组速度300米/     

镀锡线光面导电辊镀层的研制

冷轧薄板厂镀锡线是从西德引进的设备。自投产以来,每年需将十几根导电辊送往西德修复再生。为了解决光面导电辊的镀层技术,我们于1984年底开始进行光面导电辊镀层的研制。导电辊技术要求很高,生产工艺复杂严格,系西德专利。以软熔段光面导电辊为例,它需传导交流电60～230伏,6000～12000安培电流,承受200～300℃的温度及各种腐蚀。机组速度达300米/分。这种工作条件要求导电辊必须是有极其良好的导电性能,要     

导电辊的结构和电流密度的分析

介绍了电镀锡机组工艺段中导电辊的功能和结构,计算并分析了导电辊的电流密度,以此为依据来探讨导电辊在设计中可能存在的问题,结合现场实际给出了导电辊设计和维护的注意事项和建议。     

导电辊材料在模拟电镀工况条件下的磨损试验研究

针对连续电镀锌机组用导电辊的主要失效形式磨损腐蚀 ,设计了专门的试验装置和实验技术 ,简述了试验设备的基本原理和试验方法 ,并选用 SS30 4 ,SS31 6 L,HR-8,Mo4 5 Cu,N1 ,N2和 Inconel6 2 5数种样品材料及进行了磨损腐蚀试验 ;对 Inconel6 2 5不同加工工艺条件下进行了磨损腐蚀试验。其试验结果为导电辊的选材提供科学的依据。     

电镀锌机组导电辊发热的原因及其对策

依据导电辊集电环的热平衡计算,分析导电辊发热的原因,提出集电环与导电辊之间的接触面积(百分比)应大于54%;并推导出集电环表面温度的计算公式,据此能较准确地计算出集电环的温升,以便及时调整操作条件,保证机组顺行。对冷轧厂电镀锌机组导电辊异常发热的实例的解决措施,本文也作了较详细介绍。     

电镀锡机组麻面导电辊镀层修复的研究

对镀锡机组φ６００×３２２０ｍｍ麻面导电辊的镀层修复进行了研制，生产实践表明，修复后的电镀锡机组麻面导电辊的使用寿命达到了原西德同类产品的技术标准，寿命达到了８～１０个月，结束了武钢修复麻面导电辊依赖进口的被动局面。     

电镀锡机组电阻软熔控制及其供电方案优化

介绍了梅钢1420mm冷轧电镀锡机组电阻软熔及感应软熔工艺设备功能、软熔控制原理，并结合某样板机组存在10kV三相不平衡问题，有针对性地对软熔电气设备进行了优化配置。     

Failure Mechanism of Reflow Conductor Roll of Electroplating Tinning Line

In the continuous electrotinning,the strip steelis reflow treated after washing and electroplating.The purpose of reflowis to make tin react with steeland form intermetallic compound FeSn2for betteradhesion of tin and excellent corrosion resistance oftin plate[1-3].At present,there are two kinds of re-flowprocesses,namely electric resistance reflowandinduction reflow.Electric resistance reflowis of lowinvest ment and high heat efficiency,so it is exten-sively used[4].In electric resistance re…     

Composition, microstructure, hardness, and wear properties of high-speed steel rolls

The effects of alloying elements on the microstructural factors, hardness, and wear properties of four high-speed steel (HSS) rolls fabricated by centrifugal casting were investigated. A hot-rolling simulation test was carried out using a high-temperature wear tester capable of controlling speed, load, and temperature. The test results revealed that the HSS roll containing a larger amount of vanadium showed the best wear resistance because it contained a number of hard MC-type carbides. However, it showed a very rough roll surface because of cracking along cell boundaries, the preferential removal of the matrix, and the sticking of the rolled material onto the roll surface during the wear process, thereby leading to an increase in the friction coefficient and rolling force. In order to improve wear resistance with consideration to surface roughness, it is suggested that a reduction in the vanadium content, an increase in solid-solution hardening by adding alloying elements, an increase in secondary hardening by precipitation of fine carbides in the matrix, and formation of refined prior austenite grains by preaustenitization treatment be employed to strengthen the matrix, which can hold hard carbides in it.     

Effects of carbon and chromium additions on the wear resistance and surface roughness of cast high-speed steel rolls

The effects of carbon and chromium additions on the wear resistance and surface roughness of five high-speed steel (HSS) rolls manufactured by a centrifugal casting method were investigated in this study. High-temperature wear tests were conducted on these rolls to experimentally simulate the wear process during hot rolling. The wear-test results revealed that the wear resistance increased with increasing carbon content because of the increased total carbide fraction. In the HSS roll containing a smaller amount of chromium, the wear resistance was improved because it contained a number of very hard MC carbides. However, it showed a very rough roll surface because of the preferential removal of the matrix and the sticking of the rolled material to the roll surface during the wear process. Rolls containing a higher chromium content had very low surface roughness, because of the formation of a larger amount of M₇C₃ carbides of slightly lower hardness and homogeneous wear of the matrix and carbides. In order to improve wear resistance with consideration of surface roughness, the increase in the chromium content, i.e., the increase in the amount of M₇C₃ carbides, which can result in a low surface roughness, was suggested.     

1700热连轧机CVC轧辊的磨损

 研究了国内某厂1700热连轧机CVC轧辊磨损模型,分析了影响轧辊磨损的各种因素。确定了模型中主要系数数值,编制离线仿真程序,计算某一换辊周期CVC工作辊磨损,得到轧制带钢长度与工作辊中心磨损的关系及CVC轧辊磨损曲线。计算结果表明,轧制带钢长度是影响轧辊中心磨损量的一个重要因素;CVC轧辊磨损规律与普通轧辊相同,轧辊磨损对其辊形影响不大。将计算得到的CVC轧辊磨损曲线与采用高精度磨床测量得到的实际磨损曲线比较,两者吻合较好,表明此轧辊磨损计算模型具有较高的计算精度,可用于轧辊磨损在线预报。     

Thermal spray coating on conductor rolls in electroplating line

In electroplating lines,many conductor rolls are installed in electroplating bath.Typical electroplatings are tin plating(ETL) and zinc plating(EGL),and from required product qualities,a vertical cell for the former and a horizontal cell for the latter is often used.Generally,chrome plating or WC cermet thermal spray coating is applied to stainless steel conductor roll in ETL for prolonging service life by improvement of wear resistance and corrosion resistance.On the other hand,Hastelloy type alloy subs...     

CVC工作辊非对称磨损分析与预报模型建立

 CVC辊形以其较强的凸度控制能力在热连轧中有着广泛的应用,但是CVC辊形不具有均匀磨损的能力,其磨损往往比较严重,且呈现出非对称性。针对该特点提出CVC工作辊非对称磨损的表征方法,利用该方法对某1 800 mm CSP生产线下游机架CVC工作辊非对称磨损情况进行分析。统计结果表明,下游机架工作辊磨损多为非对称形式,并与CVC辊形呈现出一定的对应性。在此基础上,提出辊径对整体磨损影响系数及辊径对轧制力影响系数2个新的磨损模型参数,并建立针对CVC轧辊的非对称磨损预报模型,利用遗传算法对模型参数进行优化,并利用实测数据进行验证,改进后磨损模型精度比常规磨损模型精度平均提高了约35%。     

CSP热轧CVC工作辊磨损模型优化

通过对钢厂CSP生产线CVC工作辊磨损的实测,得到工作辊的磨损曲线.在此基础上考虑影响轧辊磨损的主要因素,建立了适合CSP生产线的工作辊磨损模型,并且借助MATLAB软件全局优化算法确定了模型中的关键参数.该模型计算结果表明,回归磨损曲线面积与实际磨损曲线面积的相对误差为3.78％,计算值与实测值之间的相关系数0.932 8,可用于轧辊磨损的在线预报.     

1 250 mm热连轧工作辊磨损控制策略

 国内大量的1 250 mm热轧机精轧机组普遍使用带有负凸度的凹形工作辊,由于轧机辊形配置及轧制工艺特点,工作辊出现严重“猫耳”型磨损,造成轧制带钢断面出现局部高点现象。为改善1 250 mm热连轧工作辊的磨损,提升带钢板形质量,提出了一种适用于1 250 mm热连轧工作辊磨损的控制策略,在保证板带稳定轧制的同时,通过轧辊辊形和工作辊窜辊策略优化来控制工作辊的磨损。本策略已应用于德龙钢铁有限公司轧钢厂,工业试验表明,该策略可减小工作辊磨损量,使轧辊磨损更加均匀,增加弯辊力调控能力,并使工作辊单位周期轧制带钢长度延长40%,对1 250 mm热连轧产线工作辊磨损控制具有研究价值和推广前景。     

CVC轧机轧辊磨损评价

对CSP连轧生产线使用的CVC轧辊磨损进行了大量实测,得到CVC轧机精轧机架工作辊的不同磨损形式,F1～F4和F7机架工作辊磨损为对称形式,F5、F6机架工作辊磨损为一端大一端小的不对称形式.在此基础上求出各架轧辊的辊形自保持参数和辊形变化特征参数,对各机架轧辊的磨损进行了分析和评价.工作辊磨损沿辊身长度方向各点磨损比较均匀,辊形自保持性较好,说明该生产线目前采用的CVC辊形曲线比较合理,能保证良好的板形控制效果.