不同抛丸介质在不锈钢热轧板除鳞工艺中的应用比较

就不锈钢热轧板抛丸除鳞的不同工艺介质在实际生产中的应用作了广泛介绍,对不同介质在实际使用中的综合效果进行了对比,指出国内抛丸介质行业在制造、销售和使用过程中存在的问题,并对国内外不锈钢冷轧厂抛丸介质的使用趋势进行了介绍.     

喷浆除鳞技术用于冷轧带钢生产

本文介绍喷浆除鳞技术在冷轧带钢生产线上的应用,着重介绍了喷射方法,除鳞效果,废液回收循环使用等情况。     

带钢表面除鳞技术的发展及应用

介绍了传统的带钢冷轧前表面除鳞技术——机械除鳞和化学除鳞的应用,及各自的优缺点,通过对无酸除鳞技术和传统除鳞技术进行比较,表明无酸除鳞技术生产效率高、速度快、环保成本低,是冷轧轧前带钢表面处理工艺新的发展趋势。     

热轧厂除鳞机的优化设计

根据工艺要求,第一除鳞机安装在加热炉与第一架粗轧机之间,主要功能是通过高压喷水去除板坯表面氧化铁皮,同时应具有良好的密封性,能够挡水、挡渣,改善周围附属设备的工作条件,且为检测仪表提供可靠的工作环境。因而除鳞机的结构优化设计直接关系到其除鳞性能,同时对周围设备的正常运行至关重要。提出的方案结构简单,控制方便,且易于改造和控制效果好。     

无酸除鳞技术浅析

针对带钢氧化铁皮处理技术中酸洗工艺存在的环境污染问题,总结分析了现行主流无酸处理技术的原理、结构及技术特点和各自的市场前景。     

冷轧除鳞中的创新技术

常见的冷轧除鳞方法包括酸洗、抛丸、滚轮、超声波、激光等，但这些方法设备笨重，成本高，还会对厂区内外环境造成一定的污染影响。由Danieli Wean United公司开发的无酸除鳞技术，给冷轧原料除鳞带来了一个新的工艺，已建立了生产能力为10万t的生产线，可望较快实现工业化应用。     

Descaling Behavior of 430 Hot-rolled Stainless Steel in HCl-based Solution

Descaling of hot-rolled stainless steel is generally implemented through pickling process in HNO3-HF mixed acids,which induces severe environmental concerns of nitrogen oxide(NOx)gases and nitrites.According to the electrochemical measurement,the mass loss test and the appearance analysis,a new pickling process which employed HCl-based solution was proposed and evaluated to provide theoretical basis for the development of environment-friendly and highly effective pickling process.Under the experimental condition,the HCl-based solution can compete with ordinary HNO3-HF mixed acids in terms of pickling efficiency,surface integrity and the removal of Crdepleted layer.The descaling process of 430hot-rolled stainless steel in the HCl-based solution consisted of three steps.The descaling solution penetrated the oxide scales into the underlying metal,dissolving the Cr-depleted layer and part of substrates.The oxide scales peeled off from the stainless steel and a polished and smooth surface was exposed.The descaled stainless steel was dissolved uniformly in the HCl-based solution;therefore,the pickling duration was vital for desired surface integrity.Under the static condition,the appropriate descaling time of 430 hotrolled stainless steel in HCl-based solution was 400 s.     

高压水除鳞技术在合金钢棒材生产中的应用

莱钢特殊钢厂小型车间在粗轧机前新增加1台高压水除鳞机,通过设置除磷点,选择喷嘴和除磷泵,对不同钢种选择不同的水压,可一次性除掉出炉钢坯表面98%以上的氧化铁皮,提高了轧辊寿命和钢材表面质量。     

精密不锈钢带冷轧生产工艺

介绍了精密不锈钢带的生产工艺,并对森吉米尔20辊轧机的某些先进技术作了详细的描述,指出精密不锈钢带冷轧生产工艺是目前较为先进的一项冷轧技术。     

冷轧不锈钢连续退火在线检测

为快速反馈不锈钢带退火质量,减少退火工艺调整时间,降低取样费用,根据奥氏体不锈钢和铁素体不锈钢的特点,用超声波和剩磁法在线检测退火后晶粒尺寸,有效控制连续退火酸洗线带钢退火性能,目前已在国内外多条冷轧不锈钢连续退火酸洗线上得到了成功应用。     

双辊铸轧704不锈钢薄带的冷轧实验

对双辊铸轧704不锈钢薄带进行了冷轧处理,分析了冷轧前后薄带的表面质量及显微组织.结果表明:在冷轧过程中,因动态再结晶和动态回复,使薄带的晶粒进一步得到细化.变形量过大时,冷轧薄带内部出现微观晶界裂纹,并随着变形量的增加最终发展成宏观裂纹.笔者还应用金属学、结晶热力学对晶界裂纹的产生机理进行了分析,认为当冷轧变形量达到一定程度后必须对薄带进行固溶处理,以避免裂纹出现.另外,结合冷轧过程中薄带板形的变化,对704不锈钢铸轧薄带给出了合理的冷轧变形量.     

Hot-dip Galvanizing of Carbon Steel after Cold Rolling with Oxide Scale and Hydrogen Descaling简

A new processing method for producing hot dip galvanized steel is designed and tested, in which pickling is skipped. Hot-rolled low carbon steel sheets are roiled with oxide scale in an experimental mill at room temperature, prior to annealing under a 20% hydrogen reducing atmosphere and galvanizing on a hot-dip galvanizing simulator. Micro-cracks formed in the oxide scale during cold rolling roughen the steel surface and enlarge the specific surface. Through-thickness cracks provide transport channels for hydrogen, and hence the reduction of oxide scale is en- hanced. When the sheet is dipped in the zinc bath, cracks are submerged by liquated zinc and the defects are not dis- tinct after hot-dip galvanizing. The overlay coating occludes with rough surface of the sheet, whereby a superior coat- ing adherence is realized.     

Fracture Behavior of Cold Sprayed 304 Stainless Steel Coating During Cold Rolling

 The fracture behavior of cold sprayed 304 stainless steel coating in cold rolling process was studied. The 304 stainless steel coatings were deposited on low carbon steel substrate by cold gas dynamic spray (CGDS) and then cold rolled, respectively. The fracture morphology of the coatings was observed and analyzed, and the crack distributions along the longitudinal rolling direction of the coatings were also investigated and discussed. The results showed that the cohesive strength of the cold sprayed 304 stainless steel coating was too low to be cold rolled. Microcracks were formed in the as-sprayed coatings and ran perpendicularly to the rolling direction. The spacing distance between these cracks decreased with the increase of the cold rolling reduction. In addition, it was also found that the initial crack generated at the surface of the coating and propagated from the surface to the interface along the weakly bonded particles. A theoretical analysis was developed for the coating fracture. It gave a critical minimum cohesive bonding strength of the coating for non-breaking in cold rolling process. The crack propagation manner of the cold rolled coatings was also discussed.     

Thermal Scratch on Surface of SUS430 Stainless Steel Strip in Cold Rolling Process

The thermal scratch significantly influences the surface quality of the stainless steel in cold strip rolling.The thermal scratch has a close relation to the rolling parameters,the rolls surface and the emulsions used in rolling.In order to explain the thermal scratch on the strip surface,the cold rolling process of SUS430stainless steel strip was investigated in the laboratory.The thermal scratch defect occurs frequently in the second rolling pass(maximum reduction in height is 32.3%),especially on the lower surface of strips.When concentration and temperature of the emulsion are the same,the thermal scratch on the surface of the strip is aggravated with increasing the roll surface roughness.With the same roll surface roughness and emulsion concentration,the thermal scratch is obviously more severe at an emulsion temperature of 63℃than 55℃.With the same roll surface roughness and emulsion temperature,the thermal scratch is distinctly weaker at the emulsion concentration of 6%than that of 3%.     

不锈钢冷轧废酸净化系统

不锈钢冷轧退火酸洗机组需要对带钢进行酸洗处理以去掉带钢表面氧化铁皮,通过对混酸酸洗产生的废酸进行树脂吸附,去掉可溶性金属离子,自由酸重新循环利用,以减少废酸排放,降低生产成本,提高酸洗产品质量。