角钢蝶式孔型的节能优化设计

过去常采用分配压下系数和压下量的方法设计蝶式孔型,虽然能满足工艺要求,但没有考虑到轧制能耗的大小。本文介绍了以轧机主电机总功率最小为目标函数的优化设计方法。优化孔型设计与现场主电机功率值的计算表明,轧制能耗可减少3.19％。     

Φ180 mm圆坯生产Φ50 mm等圆钢孔型设计

使用Φ180mm圆坯为原料生产Φ50mm、Φ60mm圆钢。对各架轧机孔型进行了设计,编制了轧制图表,生产中满足了孔型延伸系数和压下量的合理分配,工艺线稳定,产品满足标准要求。     

φ20、φ22mm热轧带肋钢筋二切分轧制

张钢棒材生产线在现有工艺设备条件下,通过改变辊径和部分减速比的方法,改变电机转速;重新分配压下量和合理设计孔型系统,实现了φ20、φ22mm热轧带肋钢筋二切分轧制。粗轧机组采用大辊径,精轧机组采用小辊径;预变形孔型K5宽、高由33mm×42mm优化为26mm×30mm;预切分孔型K4切分角由65°缩小为60°。二切分轧制的成功使钢筋的产能提高了1倍。     

型材高精度轧制工艺研究与生产实践

型钢生产企业欲扩大市场份额和提高经济效益，必须提高产品的尺寸精度。在钢材产量大于市场需求的条件下，高精度轧制显得更加重要。对型材的高精度轧制工艺进行研究，结果表明：欲实现型材高精度轧制，不仅需要高精度成品轧机，轧制工艺也须相应改进。采用合适轧制工艺，使用普通精度的型钢轧机，异形断面型钢的轧制尺寸精度可以达到冷加工的尺寸精度，直接轧制某些特定用途的机械零件。提高型材轧制尺寸精度，关键是l～2个成品和成品前孔型的轧制精度，并非需要全线轧机都要提高轧制尺寸精度。     

热轧U型钢板桩切深孔型宽展模型的研究

利用铅试样在1:10相似比,轧辊直径130 mm,辊身长度265mm,最大轧制压力150 kN,电机功率5.5kW的实验轧机上对轧辊直径1200mm,辊身长度2200 mm,最大轧制力25000 kN,轧机功率1 000 kW的钢厂轧机进行孔型轧制模拟试验,研究0.1~0.5 mm压下量,轧辊直径97.72~107.65 mm,以及轧制润滑系数0.21~0.45对轧件宽度变化的影响。结果表明,轧制的型钢宽展随压下量增大,摩擦系数的增大而增加;将复杂非对称面进分部研究后合并影响的模式研究复杂断面型钢的宽展是可行的;获得的切深孔型宽展计算模型经实验室轧制变形测量证明是有效的。     

Φ650轧机大压下量轧制Φ65mm圆钢

总结了用６６４ｋｇ锭由Φ６５０轧机经１５道次，大压下量轧制Φ６５ｍｍ圆钢的孔型设计和孔型参数的选取经验，并对工艺改进前后情况进行了对比分析。     

直径800轧机工艺孔型优化

为使原有直径800轧机能够轧制大坯料、新钢种,从钢种的物理特性和轧机孔型设计两方面进行分析.通过对20CrMnTiH钢进行热模拟实验,回归出流动应力模型;对孔型系统及轧制规程进行优化设计,提高了孔型系统的共用性.优化后的工艺不仅解决了孔型繁杂、兼容性差以及坯料尺寸小等原有的缺陷,还强化了轧制的稳定性,提高了产品质量和生产效率.     

HW175mm×175mm型钢孔型设计

以HW175 mm×175 mm热轧H型钢孔型设计为例,介绍在UEU可逆连轧机组上使用X-H轧制法生产HW175 mm×175 mm热轧H型钢,成品轧机孔型设计方法;开坯轧机孔型系统的选择及孔型设计方法;坯料断面的选择;以及使用异形坯生产HW175 mm×175 mm热轧H型钢的孔型设计特点。     

型钢孔型轧制前滑值的计算与探讨

本文提出孔型轧制时前滑值的计算应考虑宽展的影响,并说明孔型轧制时压下量的变化使单机架秒流量增减的原因是由于不同孔型系不同轧制参数下宽展不同的缘故。作者用微分法,假定宽展边缘曲线,设计出计算程序在微机上进行了计算。与传统方法比较,提高了计算精确度。     

槽钢轧制工艺设计和生产实践

文章通过槽钢孔型设计的技术特点出发。研究槽钢的工艺设计与实际生产的课题。1 前言 650轧机既能开坯又能轧制中型材的特点,在我国钢铁联合企业中曾发挥着杰出的贡献。随着连铸坯和一火成材技术的发展,650轧机开坯的使命走向终结,其中心方向是转向轧制中型材。本文介绍系列槽钢生产工艺的控制和槽钢孔型设计的一些体会。     

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。     

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.     

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。     

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)