紧凑式连轧机平辊轧制矩形件的稳定性分析

1 前言紧凑式连轧机是一种新型轧机。具有布置紧凑、压下量大、连续轧制等优点。紧凑式连轧机做为生产棒材、线材的粗轧机,采用平辊连轧,还能够提高轧辊使用寿命、降低轧制能耗,提高生产率。但是平辊轧制很容易使轧     

紧凑式连轧机的研制与应用

紧凑式连轧机是一种大压下轧制、近距离布置的粗轧机组。本文介绍了国外几种典型的紧凑式连轧机的结构优缺点,并叙述了我国自行研制的第一台紧凑式连轧机的结构特点和试用情况,认为紧凑式连轧机是小型连轧化改造中一种可优选的机型。     

经济生产型钢的新技术

近年来已经开发出许多用于生产中型和大型型钢的工艺和设备，这些工艺和设备能够使生产更加经济并能改善成品尺寸精度和机械性能方面的质量。本文论述了这些新工艺和新系统。按照小型轧机的要素来设计紧凑式大型型钢轧机，典型的范例就是韩国Kangwon Ind、Ltd的轧机和美国Steel Dynamics Inc、的轧机，它们的设计都适用于较宽范围的产品。对于轧制钢梁而言，所有产品都在一套串列可逆式轧机机组中采用X-H轧制技术进行精轧。另外，新一代的轧机机界（CCS）适用于液压压下系统和适合于快速更换品种。第一台MPS机（Mulit-Prurpose-Section/多用途型钢）已非常成功地在美国费吉尼亚洲的TXI Chaparral Steel（查帕拉尔）投产，MPS意旨在新型紧凑式轧机中，通过采用新的轧制方法将近终型连铸异形坯和直接轧制出成品结合起来。在韩国Kangwon Ind、Ltd、（江原）轧钢厂的串列可逆式轧机机组中，采用万能轧制方法已成功地轧制了钢轨。另外，适用于高速铁路用钢轨的矫直设备已在奥地利Voest-Alpinechienen（费埃斯特-阿尔卑斯钢公司）投产。西班牙CELSA（西尔萨）的中型型钢轧是最新一代中型型钢轧机的典型代表，该装备有快速更换品种装置。该轧机还配置了适用于工艺调整及工艺模型的二级计算机控制系统。为了对型材进行在线热处理，择优使用了一条冷却线来提高机械性能和产品质量。此外，对于大型SBQ棒材而言，棒材自动测量使用了监控装置。     

粗轧坯尺寸波动对轧件精度的影响

以紧凑式轧机作为高速线材粗轧机组时，由于粗轧中各机架咬入和稳态轧制的张力不同，致使坯料出口头尾尺寸波动较大。了解这种波动对成品尺寸精度的影响程度，对现场改进工艺很有参考价值。作者采用了考虑了弹跳因素的轧制力迭代方式计算了中轧以后各机架的轧制力及轧制尺寸。结果证明，中间坯尺寸波动对中轧机影响很大，而对成品影响极小。     

紧凑式轧机对横列式小型轧机的改造问题

以横列式小型机轧机的生产能力，确定了紧凑式轧机使用珠基准速度，进而分析了紧凑式轧机与横列小型轧机在生产有力匹配上所存在的问题，指出改造应向连续化方向发展。     

紧凑式连轧机的特点及其应用

本文叙述了紧凑式轧机的优点，及在国内外的应用现状，展示了紧凑式轧机在我国的发展前景。     

悬臂式轧机的结构及其特点

1 序言 随着中小型棒材连轧技术的迅猛发展,由于对产量、质量、效益的要求越来越高,对轧机的要求也越来越高,主要体现在以下几个方面:首先,要求轧机具有极高的稳定性,因而轧机必须具有较高的刚度;第二,要求具有较快的换辊速度,以提高轧机的作业率,因而要求机能实现简便、快速、可靠的更换;第三,要求轧机具有紧凑的结构以利实现轧制线紧凑式布置,节省投资;第四,要求轧     

浅谈紧凑式轧机的应用

本文概述了紧凑式轧机的特点,针对我国小型轧机和复二重轧机的现状,探讨了紧凑式轧机的具体应用方案。     

热轧宽带钢轧机工艺设备更新的合理方向

热轧宽带钢轧机是冶金工业的基础,在很大程度上决定整个工业的技术水平。近几年,国外认为最有发展前途的轧机是紧凑式轧机,轧机使用中间置重卷设备或炉内卷取机,采用混合方式浇铸薄板坯并进行轧制.用薄板坯生产的带钢的装置,特点是不仅操作费用低,而且基建费用也低。在独联体国家,大部分带材是由第二代宽带钢     

异径轧制新技术的推广和运用

本文介绍的异径轧制新技术,可明显提高轧机的薄能力和轧制精度,特别是对于全国尚在使用的属三、四十年代的、但仍在继续服役的老式二辊轧机的四辊轧机如何提高轧薄能力和轧制精度,提高轧机利用率、减少轧程和轧制道次、降低轧制压力、提高产品尺寸精度提供了有效途径。     

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.     

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)     

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.