基于PLC自动控制和红外下渣检测的滑板挡渣技术应用

通过对转炉出钢过程中前期渣、中期渣和后期渣的分析,系统对比了挡渣球、挡渣塞、气动挡渣和滑板挡渣等挡渣方式的挡渣效果。滑板挡渣通过PLC自动控制系统采集转炉倾动角度,同时利用红外下渣检测判断下渣量。根据挡渣工艺要求,滑动水口的全开或全闭可在0.5 s内自动完成,实现出钢过程中前期渣、中期渣和后期渣的最有效阻挡。与其他挡渣方法相比,滑板的挡渣成功率达到100%,转炉出钢下渣量控制在50 mm,回磷稳定控制在0.002%以下,降低了钢水氧化性,减少了合金消耗,提高了转炉成分命中率。     

滑板挡渣技术在河钢宣钢150t转炉的应用

针对河钢宣钢现有挡渣工艺存在的弊端,开发应用了滑板挡渣技术,并对其工作学理及工艺流程做了简单介绍。滑板挡渣出钢技术可在0.3 s内自动完成滑动水口的全开或全闭,实现对出钢过程中前期渣和后期渣最有效地阻挡;红外下渣检测系统与PLC控制系统的联合应用,可实现出钢过程中下渣的自动检测,挡渣成功率高达100%,转炉出钢下渣量控制在30 mm以下,回磷量稳定控制在0.003%以下。滑板挡渣工艺设施运行可靠,为提高产品质量、特别是高端品种钢开发奠定了基础,为河钢宣钢"普转优,优转特"战略的实行起到了积极的推动作用。     

转炉滑板挡渣出钢技术实践

介绍了滑板挡渣技术原理,及滑板挡渣技术在转炉上的应用和效果,滑板挡渣技术挡渣成功率高、挡渣效果好,转炉下渣量可控制在50 mm左右,为开发生产优质新品种提供质量保证。     

滑板挡渣在八钢120t转炉的应用

文章介绍了八钢炼钢厂120t转炉通过现场改进,将原挡渣棒挡渣方式改为滑板挡渣。120t转炉滑板挡渣装置与PLC红外下渣检测装置结合,实行滑板挡渣,在八钢2#转炉和3#转炉首先进行应用,取得良好效果。     

210t转炉滑板挡渣技术应用实践

介绍了新钢210 t转炉滑板挡渣与红外下渣检测技术改造及实际应用情况,并与目前常用挡渣方式进行对比分析,结果表明:转炉滑板挡渣成功率大于99.5%,出钢下渣厚度控制在50mm以下,转炉下渣及回磷量平均减少45%,取得了良好的经济效益。     

150t转炉滑板挡渣工艺技术应用实践

介绍了转炉滑板挡渣工艺技术在安钢150 t转炉上的应用情况。应用表明,滑板挡渣技术挡渣成功率高,能有效控制下渣量,改善钢水纯净度,为开发高附加值品种钢和提高产品质量奠定了基础。     

滑板挡渣系统在安钢150t转炉上的应用

简述了转炉挡渣工艺技术及滑板挡渣法的原理、结构和控制过程，并结合安阳钢铁集团公司150t转炉滑板挡渣系统的应用，介绍了适应性改造的措施和实际效果。滑板挡渣工艺的应用有效地减少了回磷及出钢过程的下渣量，达到优化钢质，提高经济效益的目的。     

典型转炉出钢挡渣技术发展现状

控制转炉出钢过程中的下渣量一直是冶金领域的研究重点。本文主要介绍了转炉出钢挡渣技术的发展，并重点分析了三种典型的挡渣技术，即滑板挡渣法、气动挡渣法以及挡渣棒挡渣法的工艺特点和应用效果。滑板挡渣技术利用上滑板与下滑板之间的流钢孔错位，从而达到控渣出钢的目的，具有滑板开闭迅速、不受出钢口寿命和炉渣粘度的影响、与下渣检测技术配合可以实现转炉一键式自动出钢的特点，该技术挡渣成功率可以达到99%以上，炉下钢包渣厚可以稳定控制在50 mm以下，效果最佳；气动挡渣技术可以通过插入出钢口的喷嘴喷出高压氮气射流，从而将炉渣挡回转炉内，该技术是无形挡渣技术的一种，具有运行成本低、效果佳的优点，但是其设备故障率偏高，同时会降低出钢口的使用寿命，故在国内未得到普及推广；挡渣棒挡渣主要采用导向杆导入出钢口方式，确保挡渣塞能够准确到达出钢口位置，从而达到挡渣的目的，该技术具有操作简单、设备投资低、效果较好等优点，在国内应用最为广泛。     

宝钢250 t转炉滑板挡渣机构耐材使用实践

通过试验并结合生产实践,对转炉滑板挡渣机构内、外部耐材的使用寿命进行了统计和分析,同时对内部耐材进行了成分改良,进一步提高了滑板挡渣机构的在线使用寿命,为滑板挡渣机构离线维护工作量的减少和滑板挡渣机构在线更换次数的降低提供了有利支撑,对国内各大钢厂正在推广使用的转炉滑板挡渣法具有很好的推广价值.     

唐钢150t转炉滑板挡渣技术的应用与研究

介绍了转炉滑板挡渣工艺技术在唐钢150 t转炉上的应用情况.应用表明,滑板挡渣技术挡渣成功率高,提高了钢水纯净度.     

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)     

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。     

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.