钛合金薄壁零件的数控车削加工工艺研究

在进行实际生产的时候,常会碰到一系列类型不同且需要加工的钛合金薄壁零件,由于其结构紧凑、质量较轻、结构小、材料省,所以在各行业得到有效运用。提高钛合金薄壁零件的加工精度,确保其质量要求,是当下急需要处理的问题。本文对钛合金薄壁零件的数控车削加工工艺进行了详细地分析与探究。     

高精度薄壁钢套类零件制造工艺

薄壁钢套类零件是机械制造中常碰到的一类难加工零件,由于其不同的功能用途和典型结构特点,其制造有一定难度,在实际生产过程中,经常出现加工制造后的零件尺寸精度、形状精度、形位精度达不到使用及设计要求。本文较系统地阐述了薄壁钢套类零件的典型制造工艺方法以及在制造过程中的变形分析和应对措施。     

关于某不锈钢薄壁零件的加工工艺探讨

针对不锈钢薄壁螺纹零件刚性差,加工过程中容易出现变形,加工精度不高等问题,在仔细分析零件结构及其加工要求的基础上,从原材料着手,对材料结构、尺寸进行优化,从设备加工能力及其原理对零件加工工艺进行改善,解决了零件的变形问题,客服了加工难点,保证了零件的加工质量,并大幅提升了加工效率。     

大腔体小出口不锈钢薄壁盲孔的生产

针对大腔体小出口不锈钢薄壁盲孔加工中出现的难点,采取了大量有效措施,给出了加工方案,解决了该零件的加工难题,为该类零件的生产提供了成功的范例。     

薄壁件接刀痕的分析及解决方案

针对生产中薄壁零件加工后存在表面接刀痕和薄壁处发生变形的原因,提出改变装夹方式、装夹顺序以及优化刀具路径的方法,改善加工零件表面精度和加工尺寸精度。通过不同方式刀具路径的对比,进而验证优化刀具路径来改善接刀痕现象的可行性。     

对半圆薄壁件加工变形分析及对策

在分析半圆薄壁件加工变形原因的基础上 ,提出了适应于精度要求较高的零件加工工艺 ,较好地解决了加工及变形问题     

铝合金复杂特征薄壁零件加工变形控制技术

通过对铝合金薄壁零件加工变形控制技术的影响因素进行分析,利用有限元研究方法对零件加工技术进行检验和技术设计的优化,并对加工标准的设定、技术位置的分布、加工材质的选择、冷却液的采用、CAM轨迹设计等方面对控制技术进行了系统研究。     

铜合金薄壁零件加工工艺探究

分析了利用铜合金挤压材加工环状薄壁零件生产过程中产生变形、尺寸超差、磕碰的原因,并通过生产实验确定了合理的加工工艺路线,降低了生产成本,提高了产品质量.     

大型铝合金薄壁件加工工艺概述

通过对吊舱侧板的数控加工实践,研究了大型铝合金框架式薄壁结构件的高效数控加工工艺技术。通过合理编制冷加工工艺规程和选择工艺参数,解决了这类零件加工过程中极易超差、工件变形等难题,可靠地满足了制造的要求。     

一种薄壁铝蜂窝零件数控加工方法

本发明涉及一种薄壁铝蜂窝零件数控加工方法。本发明在工装上纵向粘贴双面胶,将待加工零件通过双面胶粘接在工装上;然后利用刀具螺旋角度为10°～17°的球头刀切削圆弧槽,在待加工零件两端头之间的区域内下刀,两端留一定的未加工余量;接着反面去除厚度余量,在反面去除厚度余量时,根据厚度余量大小,当厚度余量不大于8mm,     

粉末冶金薄壁长筒凸台状零件压制组合模具探讨

阐述了粉末冶金薄壁长筒凸台状零件压制模具的设计，此设计不仅保证了零件的密度均匀，而且易于脱模，具有实用价值。     

楔横轧反楔堆轧改善空心零件过渡轴肩的壁厚减薄

楔横轧随形轧制空心零件在过渡轴肩位置会产生壁厚减薄,降低零件的力学强度,改善轴肩的壁厚状况是必须解决的问题.本文基于有限元模拟方法,揭示空心零件成形时壁厚减薄的产生原因,提出采用楔横轧反楔堆轧改善轴肩壁厚的成形方法,分析反楔堆轧增加轴肩壁厚的主要影响因素,从而获得轴肩壁厚增厚的成形方法和最佳条件,实现了楔横轧随形轧制空心零件轴肩位置的显著增厚.通过轧制试验,验证了有限元模拟分析模型的可靠性.      

Application of Thickness-Shaped Workpieces to Control the Wall Thickness of Lead-Formed Shell Parts

The influence of the geometric parameters of variable-thickness steel disk workpieces on the wall thickness of cylindrical shell parts with a spherical bottom, which are produced by lead stamping, is experimentally studied. The found laws of changing the dome thickness and the edge thickness of stamped parts allowed us to make recommendations for designing the lead stamping of such parts with a given wall thickness distribution.     

Changes in the mechanical properties, biochemical contents and wall structure of the human coronary arteries with age and sex

An experimental study of the mechanical properties, biochemical composition and structure was carried out on the proximal and distal parts of the right and the anterior descending branch of left human coronary arteries. The vessels were removed during an autopsy of 121 males and 84 females being 1 day to 80 years old. The material was divided into six age groups. Branchless segments of vessels 15-20 mm long were cut from proximal and distal parts. The mechanical properties of the coronary arteries were determined by passing fluid at pressures ranging from 0 to 240 mmHg. It was found that the part of the wall of the coronary artery adjacent to the myocardium is thicker in all cases than the other part of the arterial wall. With increasing age the mean thickness of the wall of both coronary arteries increases but the wall-thickening process is non-uniform in nature in both the proximal and distal parts and in the individual layers. The changes in the stretch ratio and tangential modulus in circumferential direction with age and sex were investigated. The greatest changes in the wall thickness and in the mechanical parameters were found for the left coronary artery wall in men over 40 years of age and for the right coronary artery wall in women over 50 years of age. The results of biochemical and densitometric investigations were compared.     

Two Studies that Investigate the Impact of Ceiling and Wall Reflectance Values on LEED Credits

This study is divided into two parts. The first study determines window size and size reductions for different wall and ceiling reflectance combinations that are needed in a classroom to achieve one leadership in energy and environmental design (LEED) daylight factor credit. The second study determines the power consumption of indirect luminaires with a target illuminance of 538?lux for different wall and ceiling reflectance combinations. LEED credits for the optimizing energy performance are determined. It is found that ceiling reflectance has a higher impact on light levels and energy performance than wall reflectance. A ceiling reflectance of 90% and wall reflectance of 75% allows a minimum window-to-wall ratio of 0.444 to achieve one LEED daylight factor credit. The same room decreases lighting power density for an indirect fluorescent lighting system by one-third below the maximum permissible lighting power density specified in American Society of Heating, Refrigerating and Air-Conditioning Engineers/Illuminating Engineering Society of North America (ASHRAE/IESNA) Standard 90.1-2001. If lighting constitutes 50% of the total ASHRAE/IESNA 90.1 load, 0.92 LEED credits for the optimization of energy performance can be obtained for new construction and 2.92 credits can be obtained for existing buildings.     

高温壁面凸起物对增强辐射换热的分析与计算

本文用Ｍｏｎｔｅ－Ｃａｒｌｏ方法对高温壁面布设凸起物以增强辐射换热强度的作用进行了定量的计算，并探索了在高温壁面上布设凸起物的排列方法、凸起物高度、凸起物形状等因素对增强辐射强度的影响程度     

Nineteen years experience with surgical correction of disorders of swallowing and voice following vagus nerve paralysis (author's transl)

An operation for the correction of swallowing and voice following paralysis of the vagus nerve is described. The operation is divided into four parts which are performed either in one or two stages. These include: 1. extramucosal myotomy of the pars fundiformis of the cricopharyngeus muscle; 2. correction of vocal cord paralysis by the rotation of the arytenoid cartilage and cartilage implant into the paralyzed vocal cord; 3. resection of the paralyzed wall of the pharynx; 4. fixation of the paralyzed soft palate to the posterior wall of the pharynx. Nineteen years experience with the four different parts of the operation are discussed.     

济源钢厂2号高炉设计特点及实践

济源钢厂2号高炉设计采用了一系列的先进设备和技术,如串罐式无料钟炉顶、薄壁内衬、炭砖+陶瓷杯式炉底炉缸结构、软水密闭循环冷却系统、关键部位采用铜冷却壁、炉前除尘等。高炉投产运行5年来,炉况稳定顺行,各项指标均优于设计指标,平均利用系数在3.3t/(m~3·d)以上,达到同类型高炉的先进水平。同时炉底陶瓷垫保存较好,杯垫下一层碳砖中心温度控制在600℃以内;炉底、炉缸侵蚀小,高炉冷却系统稳定,设计合理,生产实践取得良好效果。     

成组技术在冷却壁制造中的应用

通过分析高炉冷却壁的生产现状,应用成组技术的相似性原理,按照零件的局部相似性或生产过程的相似性,将零件分类成组,设计并应用了适合成组零件的组合工装,缩短了制造周期,提高了生产效率,使单件小批生产获得了类似批量生产的经济效益。     

EXCEL在机械零件设计中的应用

在机械零件设计中，运用EXCEL是提高其设计速度和质量的可行办法，通过对EXECL在机械零件设计中的应用举例，阐明了Excel在机械零件设计中的应用潜力。