排序方式: 共有48条查询结果,搜索用时 312 毫秒
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内高压成形技术现状与发展趋势 总被引:1,自引:0,他引:1
介绍了内高压成形原理、工艺分类、优点、应用范围和适用材料 ,综述了国外内高压成形在工业领域尤其汽车工业的应用情况 ,给出了用内高压成形制造的典型结构件、枝杈管件、异形管件和空心轴类件。详细介绍了国内研制的 4 0 0MPa内高压成形机参数及在该设备上试制的铝合金管件、不锈钢管件、空心阶梯轴和轿车后轴纵臂等内高压成形件。最后探讨了内高压成形需要深入研究的课题和发展趋势 相似文献
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目前,我国新投产的火力发电机组容量大、参数高,超,瞄界和超超,瞄界机组已经成为我国的主力发电机组。随着机组参数的提高,锅炉过(再)热器管蒸汽侧氧化成为影响发电机组安全经济运行的主要因素之一。本文研究了超临界电站锅炉过(再)热器管氧化皮的形成原理和规律,分析了氧化皮的剥落模式及机理,探讨了氧化皮剥落的影响因素,并提出了控制氧化皮形成和剥落的对策,研究结果可对电厂氧化皮剥落问题提供指导作用。 相似文献
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梁先林 《中国特种设备安全》2013,(10):53-54
通过对超超,豳界锅炉水冷壁爆管事故原因进行了分析,介绍了事故的处理经过,指出受热面管堵塞是造成管子超温爆管的根本原因,重点分析了受热面管堵塞爆管的各种影响因素,针对性地提出了解决措施。 相似文献
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An experimental investigation on the effects of continuous semicircular curved structure on spontaneous ignition during pressurized hydrogen suddenly release was conducted. An S-shaped tube with 700 mm in length and 10 mm in diameter was used in our experiments, and a straight tube with the same configuration was adopted for comparison. The results show that the continuously generated rarefaction waves and reflected shock waves make the pressure curves in the S-shaped tube more complicated. Meanwhile, the mean velocity and intensity of the leading shock wave undergo considerable attenuation when it propagates in the S-shaped structure. By comparing with the straight tube, the minimum critical pressure condition for spontaneous ignition in the S-shaped tube is slightly difficult to reach, but the difference is not huge. Nevertheless, the S-shaped structure can effectively promote hydrogen-air mixing and make combustion more intense. A secondary overpressure peak detected by the pressure transducer near the nozzle occurs in the spontaneous ignition cases and no such pressure increase is caught in the non-ignition cases. The transition from spontaneous combustion flame to a jet flame at the nozzle and the complete out-tube jet flame development process are captured and discussed. 相似文献
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SHUO WANG CHUNDI YU YAN ZHANG JUNPING WANG ZHENJUAN DUAN JUANKUN ZHANG 《Journal of environmental science and health. Part. B》2013,48(5):693-704
An antibody-based rapid, quantitative, and qualitative tube enzyme-linked immunosorbent assay (tube-ELISA) was developed and used to determine carbaryl (1-naphthyl methylcarbamate) residues in agricultural products (apple, Chinese cabbage, rice, and barley). The tube-ELISA is a competitive immunoassay in which the antibody is coated in the polystyrene tube, with a dynamic range between 0.7 and 46.3 μg kg?1. Carbaryl was extracted from each agricultural sample by hand-shaking with methanol and examined for application to on-site analysis. After the liquid extraction, the sample extracts diluted with buffer were analyzed by rapid tube-ELISA directly. The overall test time was around 15–30 min, including sample preparation and assay performance. The results obtained from tube-ELISA correlated well with high-performance liquid chromatography (R 2 > 0.9). The study shows that tube-ELISA is useful as a quality control tool and can be used to quantitatively detect carbaryl as well. 相似文献
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针对某炼油厂目前换热器管束泄漏事故频发的现状,研究了基于远场涡流和内窥镜的无损检测技术在碳钢换热器管束检测中的应用,并提出了通过远场涡流和内窥镜检测技术对换热管柬堵管原则进行完整性评价的方法,实现换热管束堵管的针对性、可靠性和合理性。本文所提出的各项技术的综合应用,可以最大程度地找出在用换热器已经泄漏和尚未泄漏但损伤超过临界尺寸的换热管柬,并根据切实、可靠和有针对性的堵管原则进行堵管处理,可以有效减少运行周期内换热管束的泄漏次数,对石化企业安全生产和经济效益的提高有重要影响。 相似文献
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此文围绕一个带有四个矩形缺口的圆筒形拉伸件的冲压工艺及模具设计,详尽分析了其变形规律、毛坯形状及尺寸的确定、拉伸模设计时碰到的问题及解决方法等。对类似零件的加工有较大的参考价值 相似文献