八钢成功进行高线无头焊接轧制

国际先进的高速线材轧机无头轧制接技术 ,于近日在新疆八一钢铁公司高速线材有限公司成功地进行了焊接。经过试行 ,各方面情况良好。这是无头轧制技术在世界高线轧机中首次实现了无头焊接的连续轧制。八钢的新型特殊钢高速线材轧机 ,具有国际先进水平。无头焊接轧制新工艺是在加热炉出口侧进行钢坯的自动在线对接 ,即用闪光对焊机将进入第一架粗轧机的钢坯尾部焊接到出加热炉的下一块钢坯的头部 ,使各单块钢坯变成惟一无头轧件 ,然后送入轧机进行无头轧制 ,在线焊接的过程所需时间依据所焊坯料规格的不同在 2 2～ 2 3ｓ之间变化。所能焊接的…     

棒材加热炉缩短出钢周期的实践

昆钢新区棒材生产线投产后,随着产能的释放,加热炉出钢周期逐渐跟不上轧机轧制节奏,影响产能的释放,因此,通过加热炉出钢过程中四个方面的改进,缩短出钢周期,使出钢周期与轧制节奏匹配,解决产能释放的瓶颈问题。     

钢坯焊接无头轧制在唐钢棒材生产线的应用

介绍了钢坯焊接无头轧制技术,唐钢棒线材厂采用该项技术实现了钢坯生产过程的连续化,显著提高了产量、作业率,降低了产品消耗.     

新型全热滑轨在轧钢加热炉上的开发应用

推钢式加热炉普遍存在着钢坯加热黑印严重的现象,而全热滑轨在轧钢方坯加热炉上使用易造成推钢故障,影响安全生产。介绍一种新型全热滑轨的设计与成功应用,能避免滑轨故障,提高钢坯加热质量和轧制节奏,具有较高的应用推广价值。     

低钢温轧制工艺在中厚板生产中的应用

针对低出钢温度、钢坯温度均匀性、低终矫温度等低钢温轧制核心工艺要点展开分析研究,制定出适合于3 500 mm中厚板生产线的低钢温轧制操作规程。通过优化加热炉装炉制度、精准控制出炉温度、确保100%一次除鳞率、严格控制粗轧过程钢坯扣翘、增加矫直辊外部水冷等措施,使低钢温轧制工艺在3 500 mm中厚板生产线得到成功应用。     

步进梁式加热炉低温烧钢控制技术与应用

目前,莱钢宽厚板生产线采用低温烧钢、低温轧制生产模式。当订单量大,产线满负荷生产时,低温烧钢容易出现由于加热时间短,板坯温度不均匀现象,导致轧制状态不稳定,板型控制困难等问题。因此,优化了加热炉炉温的控制,并对热送连铸坯入炉温度,不同钢种及不同规格板坯的出钢温度定制了新的工艺,既保证了低温加热钢坯温度的均匀性和板坯轧制状态的稳定性,又提高了轧线的生产效率。     

棒材零间隔轧制技术的应用与改造

正棒材生产线运行过程中,经加热炉加热好的钢坯,通过出炉辊道送入轧机轧制。轧机分为粗、中、精三个轧制机组,每个机组有6架轧机,粗中轧、中精轧机组间各有1台飞剪,用于钢坯的切头尾及事故碎断;精轧机组每个机架间有一个活套装置,用于精轧机组无张力轧制。通常,通过控制加热炉出钢速度来控制2支钢坯喂入粗轧1号轧机的轧制间隔。如果加热炉操作工对进入粗轧1号轧机的2支钢坯距离判断不准,当后一支钢坯与前一支钢坯的距离过近时,会造成2支钢追尾。此时,如果操作台发现及时,可     

单机架粗轧机配置下的2250mm热连轧线轧制节奏提升

轧制节奏与产线宽度、轧机布置、机架数量等因素有关,为了提高单机架粗轧机配置下的2 250 mm热连轧线轧制节奏,对轧制节奏的提升方法进行了研究。通过对加热炉-粗轧辊道分区改造,开发了2座加热炉同时出钢功能,实现了4座加热炉连续出钢时粗轧轧制节奏的一致性;调整了粗轧抛钢折返点,优化了粗轧负荷分配策略,减少了粗轧轧制时间;优化了中间辊道速度和精轧同步速度点,改进了精轧咬钢-抛钢的条件并实现多块钢轧制,同时提高了精轧穿带速度和加速度。通过工业应用,产线月平均轧制节奏由125 s减小到105 s,轧制节奏提升了16%,大幅提高了单机架粗轧机配置下的2 250 mm热连轧线的产能和效益,与已有报道的产线相比,轧制节奏有了明显提升。     

降低钢坯在加热炉中氧化烧损的实践

结合天钢高速线材厂的生产实践,分析了钢坯加热温度、加热时间及加热炉炉膛内气氛等因素对钢坯生成氧化铁皮的影响,提出了采用分级炉温工艺制度、停轧降温策略、分级空燃比制度、增加烟气成分在线检测设备等相应的改进措施,加热炉氧化烧损率从1.2%降低至约0.8%,成材率相应得到提高,达到保证钢坯加热质量的同时减少钢坯氧化烧损的目的。     

一种热轧自动出钢控制程序的设计和应用

在热连轧机生产带钢过程中,实现热轧机自动出钢节奏控制可以提高机时产量,还可以降低操作工的劳动强度。尤其在当前钢铁产业竞争激烈的市场环境下,热轧机自动出钢节奏控制对于产线的提产增效有重要意义。因此,有必要设计一种加热炉与轧机轧制节奏相匹配的自动出钢控制程序,以实现在连续轧制时,对轧机区前后两个轧件的间隔时间进行精确控制,即可以杜绝热轧件在轧机区停留等待造成中间轧件降温,还可以提高机时产量。     

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。     

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)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

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.     

Comparison of the results of surgical and conservative treatment of fractures of the diaphysis of the tibia

In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.