浅谈MLS立式辊磨机的安装要点

本文以MLS3626A立式辊磨机为例,介绍了立式辊磨机在安装过程中重要部件的安装及调整方法,包括基础部、主减速器、磨辊、分离器等主要部件的安装及其相关件的位置精度调整,保证磨机安装质量。     

冲击式粘土破碎机和湿粘土质原料破碎烘干机

冲击式粘土破碎机和湿粘土质原料破碎烘干机汪一佛（中国建筑材料科学研究院，北京１０００２４）１湿粘土破碎机的工作原理和技术性能１．１工作原理破碎机是由带三个活动辊和板锤转子体等部件组成的破碎系统。它主要借助高速旋转转子体上的板锤，冲击湿土块进行破碎，被...     

宽厚板轧机机架辊更换方案优化的研究与应用

机架辊是宽厚板轧机的重要部件，文章对更换机架辊过程中制约劳动效率提高的原因进行了分析，通过专用工具的应用以及方案优化，提高更换效率，降低劳动强度。     

料层挤压粉碎理论与辊筒磨

简要地叙述了料层挤压粉碎理论（压碎学说），利用压碎学说探讨了辊简磨的粉碎机制，认为辊简磨的优越性在于它的4大特点，同时进行了辊筒磨粉碎产物的微观分析和粒度分析。     

陶瓷网纹辊的日常维护与保养技术

正现代柔版印刷技术的完美实现离不开高精度的陶瓷网纹辊,它确保了现代柔版印刷技术精确体现全色调图像层次,使印制品色彩艳丽、清晰逼真,易于精确套色,适应宽幅和高速印刷。陶瓷网纹辊是柔印设备中十分昂贵的精密心脏部件,正确和及时地对陶瓷网纹辊进行正确的日常维护保养,是防止网纹辊网穴堵塞、陶瓷体损坏、延长使用寿命和获得稳定的高质量印刷品     

料层挤压粉碎理论与辊筒磨

简要地叙述了料层挤压粉碎理论（压碎学说）利用压碎学探讨了辊筒磨的粉碎机制，认为辊筒磨的优越性有它的４大特点，同时进行了辊筒磨粉碎产物的微观分析和粒度分析。     

辊式磨技术在粉体工程上的应用(三)

（续上期）４．２日本ＩＨＩ辊式磨的应用日本石川岛播磨重工业株式会社（ＩＨＩ）研制开发了多种机型的系列辊式磨,用于非金属矿物的微细或超细粉磨以及超细材料的表面改性处理。这一粉磨分级的新技术居世界领先水平,代表机型有ＩＳ型微细粉碎立式辊式磨系统、ＳＩＳ型...     

柔印预印用印刷机、网纹辊、刮墨刀（下）

4.7.2保养措施
　　网纹辊是柔性版印刷机的心脏部件，对印刷效果的影响至关重要，在选购印刷设备时，网纹辊的选择配置固然重要，但如果保养措施不当，将大大降低网纹辊的使用寿命。网纹辊的日常保养应做到以下几点：     

浅谈辊压机辊面的应用及维护

我公司自投产的#2水泥粉磨系统是采用了挤压联合粉磨系统,其系统主要配置为“HFCG120—45（右装）辊压机＋SF500／100打散分级机＋φ3．2m×13m水泥磨（开路）”,目前磨机台时产量能稳定在70t／h左右,达到了设计要求。在生产实践中发现,磨机台时的高低受辊压机辊面完好率影响很大,现就我们采取的辊压机辊面维护工艺与方法作一总结介绍,供参考。     

热轧1700生产线1#卷取机助卷辊与弧形导板问隙设定分析

卷取机是1700线热轧厂轧钢的重要设备。1^#卷取机平时经常发生助卷辊运行较长一段时间后，1^#助卷辊和2^#助卷辊与弧形导板间隙变小，3^#助卷辊与弧形导板间隙变大。导致的后果就是1^#、2^#助卷辊与弧形导板摩擦阻转（简称“啃辊”），3^#助卷辊与弧形导板间隙过大导致“钻钢”现象。针对上述现象，通过实际检测和分析，找出原因，在设备安装时重新对助卷辊和弧形导板间隙进行调整，消除了上述状况，提高了轧钢的产量和质量。     

高速瓦楞辊机构中高度的动力学分析

首先论证了高速瓦楞辊机构中高度的动力学特性，建立了相应的设计中高度的数学模型，推导出对应的动挠度方程，确定辊轴加工测量等分段截面的挠度曲线，有利于编制通用的宽窄幅不同结构尺寸的计算机辅助设计程序。     

Roller path design by tool compensation in multi-pass conventional spinning

In conventional spinning, multiple roller passes are required to prevent material failures and to minimize thinning of wall thickness of spun parts. In the present industrial practice, the process design still relies on the trial-and-error approach to determine roller path and passes. In this paper, a tool compensation technique has been proposed and employed in multiple roller passes design, to ensure the workpiece fully conforming onto the profile of a mandrel. The Taguchi method is applied to design experimental tests and analyze the effects of material type, feed ratio and spindle speed on the dimensional variations of the spun parts. Finite element simulation is conducted to investigate the variations of tool forces, wall thickness and strains in this multi-pass conventional spinning process. The results show that the tool compensation technique can effectively prevent material wrinkling failures in the process. The type of material has the most significant effects on the variations of thickness and depth of the spun parts, followed by the spindle speed and the feed ratio. High feed ratios can help to maintain the original wall thickness unchanged but cracking failures may occur if a larger feed ratio is applied.     

Computational model for determination of dynamic load capacity of large three-row roller slewing bearings

In the presented paper a calculation procedure for determination of dynamic load capacity of large three-row roller slewing bearings is presented. The calculation procedure consists of three main parts: (i) determination of internal contact force distribution in a large three-row roller slewing bearing with consideration of bearing clearances and ring support deformations, (ii) determination of stress field in the contact area between raceway and rollers as a consequence of contact forces and (iii) determination of the bearing’s fatigue life due to contact fatigue of the raceway. The internal contact force distribution is determined numerically by using a symmetry 3D FEM-model of a large three-row roller slewing bearing. Another numerical procedure is used to determine the stress field in the contact area between rollers and raceway. This problem is studied on different roller types: cylindrical roller (without profile correction), fully crowned roller (logarithmic-profile) and partially crowned roller (ZB-profile). Numerically determined contact stresses then serve as a basis for fatigue analyses, where the bearing’s service life of the bearing is determined by using the stress-life approach, considering typical material parameters of the bearing’s raceway.     

Three-dimensionally printed designable joint for carbon fibre reinforced plastics

Three-dimensional (3D) printing of carbon fibre reinforced plastic (CFRP) components shows promise for building light-weight strong components for industry. Many structures require multiple components to be joined to form the completed parts. However, tightening of metal bolts used to join CFRP can damage the composite and the bonding strength of adhesive bonding is variable. Here, we propose a new joint system, based on all-3D printed parts. Snap-in joints and Ajax-pins induce a mechanical joining force at the interface between parts, together with a bearing force. This joint system offers comparable strength to that of adhesive and metal bolt joints, while adding negligible weight to the parts. Furthermore, 3D printing of the surface structures, holes and pins enables unprecedented control over the joint design, enabling strength optimization through the thickness and in-place directions as required. The Snap-in joint system shows great potential for the fabrication of strong light-weight 3D printed structures.     

利用关联关系的标准件参数化设计方法

分析了产品几何建模的参数化设计方法,提出了一种基于关联关系的标准件参数化设计方法。阐述了参数化设计方法的原理,即采用关联参数建立多个组件间的关联,以实现标准件的参数化设计。利用CATIA平台,给出了圆锥滚子轴承基于关联关系的参数化设计过程,证明了该设计方法的可行性。     

Continuous flexible forming of three-dimensional surface parts using bendable rollers

A novel idea to form three-dimensional (3D) sheet metal parts using three bendable rollers is presented. It can realize a continuous flexible forming of sheet metal. The forming principle is introduced and forming equipment with three bendable rollers has been developed. The bendable roller with shape-adjusting device is designed based on a flexible shaft of steel wires. Some experiments were performed and typical 3D surface parts were formed. The experiments show that the transversal spine of 3D part is determined by the bended shape of the bendable rollers, and the longitudinal spine of the 3D part is determined by the relative displacement among the top roller and the two bottom rollers. The technology of forming 3D surface sheet metal using bendable rollers can produce 3D surface parts in a rapid and economical way.     

工艺参数对薄壁件多道次旋压变形均匀性的影响

目的研究成形工艺参数对薄壁件多道次旋压变形均匀性的影响。方法采用试验的方法,研究了双轮数控旋压成形铝合金薄壁件过程中,旋压间隙δ、进给率f和旋轮圆角半径R等关键工艺参数,对制件表面质量和壁厚均匀性的影响。结果 3个工艺参数都对制件表面质量和壁厚均匀性有影响。结论减小旋压间隙δ、采用较大的主轴转速S和较小的进给率f可提高零件的表面质量和尺寸精度。改善零件壁厚分布的均匀化程度,适当提高旋轮圆角半径R,也能使变形的均匀化程度提高。     

Repeated plastic deformation as a cause of mechanical surface damage in fatigue, wear, fretting-fatigue, and rolling fatigue: A review

After studying statements bringing together essential features of the fatigue behaviour of metal structures in service, it is shown that the elementary phenomena of plastic deformation and fatigue crack propagation, which explain the fatigue behaviour of notched parts, also play an important role in other modes of damage of machinery parts. This is the case for mechanical surface damage under repeated bearing pressures in the absence of any apparent lateral sliding, for fretting-fatigue in which there is alternating lateral displacement of very low amplitude, and for false-brinelling marks in ball or roller bearings. It is also the case for unidirectional friction wear and for rolling damage, either with friction in gears or with very low friction in ball or roller bearings.     

高温合金薄壁W截面密封环滚压成形壁厚变化研究

目的研究滚压成形过程中环件壁厚的变化规律。方法基于ABAQUS/Explicit平台建立了GH4169薄壁W截面密封环多道次滚压成形三维弹塑性有限元模型,分析了滚压成形过程中环件壁厚沿周向及轴向的变化情况以及工艺参数对环件壁厚变化的影响规律。在此基础上,进行与模拟条件一致的试验研究,并与模拟结果进行了对比分析。结果滚压成形过程,环件壁厚沿周向分布均匀而沿轴向分布不均匀;随着变形量增大,减薄带宽度增大;进给辊进给速度增大,环件壁厚不均匀性加剧;随着驱动辊转速、进给辊与环件间摩擦因数的增大,环件壁厚减薄呈减小趋势。结论环件滚压成形过程中,应合理分配各道次变形量,适宜的工艺参数为:驱动辊转速为2 rad/s,进给速度为0.2 mm/s,摩擦因数为0.1。     

A novel spinning process for simultaneously producing two cone parts with big angle

ABSTRACT

A new spinning forming method for simultaneously producing two cone parts with big angle was developed. The novel process with three passes was generated. The 3D finite element (FE) model of cone parts was established using ABAQUS software. Based on the metal plastic forming principle and the characteristic of spinning, technical parameters including the angle of forming surface and the radial feed speed of the roller, the spindle speed and the friction coefficient were determined. Based on the secondary development of above FE model, the fittability of cone parts was obtained, which is of great significance for improving the performance of cone parts.