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1.
针对单轴传动滚切式双边剪生产过程中出现的薄钢板经双边剪剪后出现“错牙”及“飞边”的问题,从多个方面入手对薄钢板出现“错牙”及“飞边”的原因进行了分析对比,提出了相应的解决方案,对今后滚切式双边剪的设计、制造及安装调试有借鉴和参考价值。 相似文献
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O.E.E.K. Omar T. El-Wardany E. Ng M.A. Elbestawi 《International Journal of Machine Tools and Manufacture》2007,47(7-8):1263-1275
During the milling operation, the cutting forces will induce vibration on the cutting tool, the workpiece, and the fixtures, which will affect the surface integrity of the final part and consequently the product's quality. In this paper, a generic and improved model is introduced to simultaneously predict the conventional cutting forces along with 3D surface topography during side milling operation. The model incorporates the effects of tool runout, tool deflection, system dynamics, flank face wear, and the tool tilting on the surface roughness. An improved technique to calculate the instantaneous chip thickness is also presented. The model predictions on cutting forces and surface roughness and topography agreed well with experimental results. 相似文献
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在宽厚板项目中,双边剪用来剪切钢板两个纵边,以达到厂家要求的钢板宽度。本文除了介绍宽厚板双边剪的系统配置及功能特点外,主要阐述智能剪切的自动控制。本着降本增效的原则,开发一种新的主传动控制模式,优化双边剪电机剪切程序,在钢板厚度满足设定条件的前提下,固定侧与移动侧各采用一组电机驱动剪刃,并且实现主从电机智能激活切换模式,以满足生产需要。经实践证明,优化后的控制系统不仅提高了生产效率,还实现了节能降耗、安全生产的目的。 相似文献
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Ana Paula Vieira Soares Manuel Farinha Portela Alain Kiennemann 《Catalysis Reviews》2005,47(1):125-174
This review deals with the important industrial reaction of formaldehyde manufacture by methanol oxidation over iron molybdate catalysts. Detailed reference is made to the used catalyst, preparation techniques (coprecipitation, sol-gel like, mechanical mixing, etc.) including unsupported and supported catalysts, promoters and characterization methods. The controversial active phase assignment (stoichiometric versus Mo rich iron molybdate) is discussed. The proposed reaction mechanisms and kinetic laws for the main and side reactions are examined. The catalyst deactivation processes are reviewed and the role of Mo excess on these processes is underlined. Finally conclusions and perspectives are presented. 相似文献
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《矿业科学技术学报(英文版)》2016,26(5):869-875
To study the stability of the west slope in Buzhaoba Open-Pit Mine and determine the aging stability coefficient during slide mass development, the deformation band of the west slope and the slide mass structure of the 34,600 profile are obtained on the basis of hydrology, geology, and monitoring data.The residual thrust method is utilized to calculate the stability coefficients, which are 1.225 and 1.00 under sound and transfixion conditions, respectively. According to the rock damage and fragmentation and the principle of mechanical parameter degradation, the mechanical models of the slide mass development of the hard and soft rock slopes are established. An integrated model for calculating the slope stability coefficient is built considering water, vibration, and other external factors that pertain to the structural plane damage mechanism and the generating mechanism of the sliding mass. The change curve of the stability coefficient in the slide mass development is obtained from the relevant analyses,and afterwards, the stability control measures are proposed. The analysis results indicate that in the cracking stage of the hard rock, the slope stability coefficient decreases linearly with the increase in the length Lbof the hard rock crack zone. The linear slope is positively correlated to rock cohesion c. In the transfixion stage of the soft rock, the decrease speed of the stability coefficient is positively correlated to the residual strength of the soft rock. When the slope is stable, the stability coefficient is in a quadratic-linear relationship with the decreased height Dh of the side slope and in a linear relationship with anchoring force P. 相似文献
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Shi Hyoung Ryu Hae Sung Lee Chong Nam Chu 《International Journal of Machine Tools and Manufacture》2003,43(14):2177
In this research, an effective method for the form error prediction in side wall machining with a flat end mill is suggested. The form error is predicted directly from the tool deflection without surface generation by cutting edge locus with time simulation. The developed model can predict the surface form error accurately about 300 times faster than the previous method. Cutting forces and tool deflection are calculated considering tool geometry, tool setting error and machine tool stiffness. The characteristics and the difference of generated surface shape in up milling and down milling are discussed. The usefulness of the presented method is verified from a set of experiments under various cutting conditions generally used in die and mold manufacturing. This study contributes to real time surface shape estimation and cutting process planning for the improvement of form accuracy. 相似文献
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