热轧粗轧机万向接轴断裂分析

为分析断裂原因,建立了某热轧厂R2轧机包括叉头、十字轴和万向接轴的三维接触模型,分析在不同平衡力以及过载极限转矩和疲劳转矩下接轴的强度。计算结果表明,接轴断裂的原因主要是在转矩作用下,支撑部位的强度不足造成的,接轴过平衡还是欠平衡时产生的附加弯矩的影响可以忽略。     

四辊轧机万向接轴附加弯矩及轴向压应力分析

分析了四辊水平轧机主传动万向接轴在传动的过程中,万向接轴叉头产生的附加弯矩,并分析了该附加弯矩在传动系统轴向定位面所产生的轴向压应力,供设计万向节轴时参考.     

2300 mm中板万向接轴断裂原因分析

通过对事故现场万向接轴断裂的位置、外观形貌观察,结合实际生产过程中万向接轴平衡压力情况,并依据设计要求,经过计算分析,最终准确判断出万向接轴的断裂原因。通过对平衡压力参数的调整,彻底消除了事故隐患,延长了万向接轴使用寿命。     

大型轧机主传动万向接轴结构的分析与改造

通过研究中厚板轧机主传动万向接轴的结构形式,对接轴存在的轴向窜动余量过小、接轴平衡连杆强度低等问题进行了整体改造,重新设计万向接轴结构和平衡龙门架,用十字轴式接轴代替虎口滑块式接轴,达到了轧机稳定、高效运行的目的。     

热轧粗轧机万向接轴故障分析与改进

针对天铁热轧生产线粗轧机主传动万向接轴存在的接轴晃动大,平衡支架晃动,十字包频繁损坏等故障,通过改造十字万向节扁头孔,定期测量并更换工作辊和支撑辊衬板窗口尺寸,定期检修轧机平衡系统,改进轴承润滑制度等措施,消除了各种故障,延长了万向接轴的使用寿命,降低了生产成本,保证了设备的正常运行。     

中板轧机滑块式万向接轴自动润滑装置研制

介绍一种用于中板轧机滑块式万向接轴的自动润滑装置。当轧机旋转时 ,固定在万向接轴平衡托瓦上的模板使固定在万向接轴上柱塞泵内的数个柱塞做往复运动 ,万向接轴旋转一周柱塞泵完成吸油和压油一个周期 ,柱塞泵压出的干油通过固定在万向接轴上的油管送至滑块与扁头或滑块与叉头摩擦表面 ,为摩擦表面提供良好的润滑条件 ,以避免滑块的发热和烧毁现象     

万向轴倾角对热连轧机振动的影响研究

四辊轧机在轧制过程中,辊系受力非常复杂,研究辊系的振动除考虑其它因素外还应考虑万向接轴附加弯矩的影响。建立工作辊耦合动力学模型,证明辊系振动存在水平和垂直方向的耦合关系,并进行数值仿真,得出万向轴倾角的存在使部分扭振转换成万向接轴弯振,进而影响辊系的动力学特性;仿真表明,万向轴倾角在一定角度下位移响应会出现分岔等现象。     

棒材精轧机组平轧机接轴改造

棒材平轧机与减速机之间采用十字轴式万向接轴联接时,受轧机机组运行速度、万向接轴自身重量等因素影响,严重影响成品质量,缩短万向接轴寿命。通过优化设计、提高零部件强度等措施重新制作新接轴,投入使用后产品质量比较稳定,延长了接轴寿命,降低了备件消耗。     

板材矫直机传动轴扭矩在线监测的研究与应用

针对邯钢中板厂板材矫直机主传动万向接轴频繁断裂问题,开发了采用焊接式全桥电阻应变片变形评估扭矩值的控制技术,增加主传动万向接轴扭矩监测装置,实现扭矩的实时监测.通过采集扭矩数据,分析研究万向接轴的损坏失效原因,制定合理的应对措施,有效避免了万向接轴断裂的再次发生.     

轧机联接轴平衡装置型式的探讨

联接轴平衡装置通常有3种型或：弹簧平衡、重锤平衡和液压平衡。在现代轧机中已较少采用弹簧平衡装置。重锤平衡装置结构简单可靠，但设备基础结构较复杂，基础较深，现代轧机越来越多地采用液压平衡装置，它具有良好的使用性能，平衡力不随接轴位移而变化，可加速换辊过程，近年来出现了新型的接轴平衡装置，如固定式接轴平衡装置和杠杆式平衡接轴装置，二者都有一个杠杆通过铰链连接上下接轴支承座．可以适应上下接轴中心距的变化，起到自身同步平衡和减振作用。     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)