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91.
本文介绍应力分析设计法的原理,通过有限元计算得到汽包封头的温度场、应力场,并以应力分析为基础对汽包封头强度作了校核。 相似文献
92.
Experiments have been carried out on relatively wide angle-ply laminate samples with very short gauge lengths. These proved to be very much stronger than samples tested in earlier work, and which form the basis for our present design with these materials. It is highly likely that the early results for strength were more indicative of edge effects than true laminate strength. This is confirmed by data from tests on pressurized tubes. A review of the literature on this shows that such tests produced results which can be an order of magnitude higher than the early laminate tests. Thus our design calculations could well be severely underestimating the potential strength of angle-ply laminates. This may be having serious consequences for the aerospace industry, through the use of design criteria for strength which may be too conservative. Single-fibre experiments may pave the way for more realistic estimates of angle-ply laminate strengths. These indicate that a simple one-third power rule can be used to estimate the potential strength. However, this is purely ad hoc at present, and needs to be put on a firmer footing through both theoretical and experimental studies. Furthermore, if this approach is adopted, edge effects will still have to be allowed for, and estimated on the basis of the aspect ratio of the part. 相似文献
93.
钟京卫 《石油化工设备技术》2002,23(2):46-49,59
通过对高强钢焊接性能的分析 ,提出了高强钢冬季焊接施工带来的问题及处理办法。可靠的焊前预热和焊后保温是确保冬季焊接施工质量的关键措施 相似文献
94.
添加煤沥青提高焦炭强度的研究 总被引:2,自引:0,他引:2
本文进行了煤和煤沥青共炭化试验,将煤沥青添加到20kg焦炉内进行炼焦试验。结果表明,煤沥青对武钢用煤有一定的改质作用,添加煤沥青可提高焦炭强度。 相似文献
95.
96.
S—135钢板是水电站用高强耐磨不锈钢板,既要求强度高、韧性好,又要求耐磨、耐蚀性强,生产难度较大。除我厂外,目前国内尚无其它厂家能够生产这种钢板。该钢板在加热轧制,冷却过程中要解决很多技术难点。我们通过采用特殊的控制轧制和控制冷却工艺,很好地解决了诸多技术难点,使S—135钢板的开发研制取得了成功。为电站用高强度耐磨不锈钢生产提供了宝贵的经验,也为控制轧制及控制冷却技术在中板生产行业的应用起到了积极的推动作用。 相似文献
97.
Abstract This study deals with the modeling of air pollution in apartments from laboratory measurements of source strengths, using formaldehyde and Total Volatile Organic Compounds (TVOCs) as model pollutants. The sources in two test apartments were grouped into two: building-related sources and occupant-related sources. The measured source strengths and ventilation rates were used for the prediction of concentrations expected in the apartments. These predictions were compared to measurements in the apartment over 12 months. The conclusions were that the model predictions based on emission rates measured in the laboratory can be used to predict the long-term concentration of the two model pollutants in the apartments. Considering the measured differences in ventilation between the apartments, an occupant emission rate of between 0.2 and 0.3 mg/h/kg body weight could be estimated. Based on previous suggested limits of acceptable exposures of humans to VOCs, an acceptable average emission rate of VOCs from building materials in general was estimated to be about 30 (μ/m2/h. The modeling showed that during the first 200 days, building materials dominated the emissions. After this, sources relating to the occupants dominated. On average about half of the VOC pollution originated from the building materials. 相似文献
98.
Mei Xuan Xu Wen Guang Liu Yun Lin Guan Zuo Peng Bi Kang De Yao 《Polymer International》1995,38(2):205-209
The phase behavior of a hybrid polymer network (HPN) composed of poly[(propylene glycol maleate)-co-(propylene glycol phthalate)] crosslinked with styrene and polyester–urethane crosslinked with methylene-bis-ortho-chloroaniline was examined. The correlation between phase separation and impact strength of the HPNs is discussed. The composition of HPNs has an effect on their properties. 相似文献
99.
岩石液压致裂中几个问题的研究 总被引:1,自引:1,他引:0
论证了流体压力变化与岩石强度变化之间的关系,阐述了流体保持与释放的应力条件和构造环境,总结了两种围岩下的液压致裂模型及其流量方程。 相似文献
100.