二冷轧引进镀铬辊新技术 解决汽车板表面质量难题

2006年10月，二冷轧引进德国镀铬辊新技术，开始了镀铬辊使用的研究与应用。从05板、03板表面粗糙度控制人手，对镀铬辊的轧制周期进行研究，将研究重点放在镀铬辊对钢板宽度变化后产品表面的影响上和轧机镀铬辊的使用上。     

单机架平整轧辊镀铬及实用研究

本文阐述了φ610×1700×3745mm单机架平整工作辊镀铬的设备,工艺流程和镀铬辊装机实用试验的情况。试验结果表明:镀铬辊的铬层结合力良好,在轧钢过程中无任何起皮剥落现象,耐磨性能高,抗事故能力强,镀铬辊的平均使用寿命为普通辊的4倍,并且改善了轧制的带钢表面质量,同时实现了自由轧制。     

河钢邯钢2180平整机镀铬辊表面色差原因分析

以平整机镀铬辊为研究对象,通过对比实验,系统分析了冷轧带钢表面色差的产生原因。带钢表面色差实际上受镀铬辊色差的影响,与镀铬工艺有关。通过调整预热时间和温度、提高镀液浓度和温度、合理控制电流密度、控制铬层厚度,消除了因镀铬工艺引起的冷轧带钢表面色差,满足了生产线的用辊需求。     

冷轧工作辊镀铬和应用

对φ90/φ240×300mm 四辊轧机冷轧工作辊进行了电镀铬和轧钢生产应用试验,结果表明,镀铬冷轧工作辊的使用寿命为未镀铬辊的2—3.5倍,所轧制的钢板表面平整光滑,质量稳定。     

冷轧机及平整机工作辊的硬铬涂层

引言 根据NEO公司与安大略省的加拿大轧钢厂的联合研制工作,于1964年实现了硬铬涂层工作辊的首次成功应用。 在冷轧机和平整机中使用镀铬辊已在世界上的一些国家中得到推广,而且被认为是与冷轧相关的一种必备技术,可应用于新老轧钢厂中。     

轧辊镀铬技术及其应用前景

一、前言在生产冷轧薄板的过程中要消耗大量的轧辊。为了延长轧辊使用寿命,降低生产成本,加拿大NEO工业有限公司于六十年代开发了冷轧工作辊镀铬技术,并逐步推广到欧、美、日、澳大利亚和南朝鲜。冷轧工作辊镀铬以后可提高其使用寿命,减少停机换辊时间,提高轧机作业率,同时还可以改善冷轧板表面质量。我国轧辊镀铬工作起步较晚,国内也很少报道这方面的技术资料。为了研究和推广轧辊镀铬技术,1988年武钢钢研所和机总厂一起,对φ90/φ240×300毫米四辊轧机冷轧工作辊进行了电镀铬和轧钢生产应用试验。     

高精度铝板矫直机工作辊薄层镀硬铬

高精度铝板的矫直,不仅要求矫平精度高,而且要求矫直后的板面没有因矫直过程而产生的划伤、压痕、亮带等附加于来料的缺陷,特别是在对镜面铝塑板与装饰板的矫直中,保持板面光洁度尤为重要。工作辊采用辊身薄层镀硬铬工艺是保护板面精度,提高辊子使用寿命,降低辊耗的有效措施。根据工作辊的使用条件,介绍了其镀铬种类、镀铬特点和镀层的失效与返修。     

提高汽车钢板表面质量的新方法

日本NKK公司与日本Nomura镀层公司共同研究成功轧辊电镀铬工艺,提高了轧辊的硬度和耐磨性能,改善了钢板质量。新开发的工艺己正式用于NKK公司的福山厂。其工艺是:将用磨剥加工并用电火花进行麻面处理的工作辊运至镀铬车间,依次送入各处理槽进行脱脂、表面处理、热水清洗和电镀。工作辊镀铬层的厚度极为重要。镀层太     

张力辊表面处理工艺的应用分析

为提高张力辊辊面性能,分别采用在辊面电镀硬铬、HVOF喷涂WC-12Co、HVAF喷涂WC-12Co三种工艺对张力辊辊面进行强化处理,并对随辊试样进行分析。发现镀铬层内部存在一定的微裂纹,硬度达到900HV_0.3;HVOF制备的涂层孔隙率为2.3%,涂层硬度1 100HV_0.3;HVAF制备的涂层孔隙率为0.6%,涂层硬度1 400HV_0.3;三种工艺制备的最终辊面粗糙度Ra均能满足上机使用要求,镀铬辊使用6个月后,辊面粗糙度下降严重,而WC涂层辊面的粗糙度保持相对稳定。     

轧辊表面镀铬对冷轧变形区润滑的影响

模拟轧辊表面镀铬工艺,对镀铬轧辊及非镀铬轧辊在同一润滑介质条件下对辊缝变形区润滑的影响进行了研究。结果表明,在同一润滑介质下,钢-钢摩擦副与钢-铬摩擦副的摩擦系数及润滑油成膜性能均有明显不同。钢-铬摩擦副的摩擦系数比钢-钢摩擦副的摩擦系数降低20%以上,在其它实验参数相同的条件下,冷轧润滑油在镀铬表面所形成的油膜厚度比非镀铬表面提高1倍以上。     

中厚板头部弯曲的正交实验及分析

模拟现场生产条件,采用正交实验法对中厚板轧制过程中板头弯曲问题进行了研究.分析了轧制过程中影响钢板头部弯曲的因素,得到各影响因素按其重要性由大到小的排序为:变形区形状参数、轧机上下辊转速比、上下辊辊径比、导入角、来料厚度、摩擦状况,并得到了各影响因素的最佳水平.实验还表明:采用正交实验法显著加快了实验进程,减少了实验周期和实验成本,较快地达到了实验目的.     

锥辊辗轧理论研究的进展

锥辊辗轧理论的研究开拓了带材轧制和随后深加工的新领域。它利用楔形轧制和异步轧制的若干特点，以构成一个新的轧制过程，提供了高效，低耗和柔性加工钢带和螺旋叶片的可能性和现实性。本文对钢带锥辊异步冷辗轧，螺旋叶片锥辊冷辗轧等程的理论研究作一较详细的阐述。以推进这方面的研究。     

Investigation of the kinematics of powder motion in hoppers during rolling

Summary The authors investigated the kinematics of the motion of powder in the hopper when the powder in freelypoured into a gap between stationary rollers, during rolling on mills having rollers of various diameter with varying thickness of feeding during horizontal and vertical direction of rolling and during rolling of three-layer strips.The nature of the non-uniformity of feeding of the powder into the deformation zone was established in relation to the hopper width and the nature of the displacement of the powder during the rolling of three-layer strips.The distribution of speeds in the cross section of the exit of the powder of the shell into the deformation zone during the rolling of three-layer strips is determined.     

Optimizing Rolling Patterns for Chip Seals Using Laboratory Aggregate Loss Performance Tests on Field Fabricated Samples

This paper presents a study to determine the optimal rolling patterns for chip seals based on aggregate retention performance. Chip seal sections composed of single seals of granite 78M and CRS-2 emulsion are constructed using five different rolling patterns with two or three rollers. Both pneumatic tire and combination rollers are used in developing these patterns. Chip seal samples are obtained from the sections for laboratory testing. The aggregate retention performance is evaluated using the flip-over test, Vialit test, and the third-scale model mobile loading simulator. It is found that the time delay between aggregate spreading and rolling is an important parameter for the aggregate retention performance. The laboratory aggregate retention test results are used along with typical roller speeds and the maximum allowable time delay between aggregate spreading and rolling to develop optimal rolling patterns for two and three rollers.     

型钢车间半连续化改造实践

莱钢锻压厂型钢车间对原横列式精轧机组一、二部车交叉辊道、粗轧机后升降台、加热炉区及中轧机组和精轧系统进行了一系列的技术改造,达到了提高轧制节奏、设备作业率,减少过程轧废,提高成材率的目的,使工艺更加合理,并在此基础上提出今后改造发展方向。     

Longitudinal rolling in helicoid rollers

A new method of sheet rolling in helicoid rollers is considered. In this approach, the roller barrel is formed by a helicoid with rounded projecting tips. The effectiveness of the rollers is demonstrated, and their geometric parameters are determined. Depending on the mutual orientation of the rollers’ helical barrel surfaces, rolling will produce linear hardened zones on the strip, at some angle to its longitudinal symmetry axis. Such nonuniform deformation increases the strength of the sheet, thanks to the formation of local hardened zones, without overall loss of strip plasticity.     

高精度、硬齿面齿轮在冷轧机减速箱中的应用

偏八辊轧机主传动减速箱在使用中存在的问题及针对该问题所进行的齿轮材料、热处理手段、齿轮精度等级等诸方面的研制改进,对轧机的正常生产提供了必要的保证。     

FEM Analysis of Physical Field in Level Rolling Process of Inversion Casting by ANSYS Program

Ininversioncastingprocessmothersheetisledthroughameltwhichthencrystallizesonthesurfaceofthestrip.Throughacoupleoflevelrollersabovethemeltthecastingstripisroughlyrolled,thefigureisshownintheReference[1].Levelrollingisveryimportantintheprocess.　　ThevaluesimulationtechnologyonthebasisofFEMhasbeenusedgraduallyinthefieldofmetalplasticforminginrecent20years.Thetheoriesareadoptedfromsmallelastic-plasticdeformationFEMtobigelastic-(viscidity)plasticdeformationFEM,andtheanalysistechnologyisbecomin…     

型钢轧辊降耗

加强轧辊现场管理，合理组织生产，保持均衡轧制，采用带槽辊、热处理辊和堆焊辊等新工艺、新材质，及时开展对轧辊的修复、改制和再利用工作，均是有效实现型钢轧辊降耗的实用途径。     

Rolling of metal balls

The rolling of balls (diameter 93 and 125 mm) of precise mass in helical grooves is simulated by means of QForm-3D and DEFORM-3D software. A model of a virtual rolling mill is created. Analysis of the stress state at characteristic points along the rolling axis focuses on the effective stress, the components of the stress tensor, and the mean normal stress. The mass of balls rolled on new and worn rollers is measured. The quality of internal metal layers is verified, and the hardness of rolled balls over the vertical and horizontal symmetry axes is measured. Modeling of ball rolling shows that the hot blank (a rod of hot-rolled steel) is satisfactorily captured by the rollers. Rolling is stable, without slipping. The blank completely fills the grooves; no gaps are observed between the metal and the walls. The crosslinks between the balls are completely eliminated within the rollers. The crosslinks are cut by the rim of the rollers and pressed into the body of the ball. The individual balls continue to roll along the finishing section of the groove; the stubs of the crosslinks are smoothed; and a completely shaped ball with a smooth surface emerges from the rollers. In modeling the stress–strain state, all the components of the stress tensor are negative. In other words, all the components of the stress tensor are compressive in rolling of the balls. Statistical analysis of the data from weighing of the rolled balls (diameter 93 and 125 mm) shows that the mass deviates from the required value by no more than 1%. Measurement of the hardness over the diametric cross section of the balls shows that there is no decline in hardness in the internal layers. That indicates high quality of the ball core.