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气—液式热管换热器在硫酸工业中的应用研究 总被引:4,自引:0,他引:4
本文研制的气-液式热管换热器应用于硫酸生产中SO3气体的余热回收。它具有传热性能好、流动阻力小、寿命长、体积小、节能效果显著和易清垢等优点。 相似文献
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Sun Linzhi Luo Yi Zhang Yanan Sun Ping Qin Xinjie Gong ZhenbangPrecision Machinery Institute Shanghai University Shanghai China 《机械工程学报(英文版)》2002,15(4):303-307
An experimental bimorph piezoelectric element (PZT) actuator for small pipe robot is developed. The robot can move in φ20 mm pipe, and can carry a CCD camera for detecting cracks or fine holes on inner surface of pipe. The velocity of the robot can reach 17~22 mm/s for vertical pipe up/down, respectively. Moving principle and its performance characteristics are presented. 相似文献
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Erosion is one of the most serious problems in various gas and liquid flow passages such as flow in pipes, pumps, turbines, compressors and many other devices. Sand presence causes loss of pipe wall thickness that can lead to pipe erosion, frequent failures and loss of expensive production time. The importance of this problem is mainly due to many related engineering applications, viz. heat exchangers. In order to reduce the frequency of such pipe erosions, caps in the form of replaceable pipes are protruded in the sudden contraction regions which are exposed to most of the serious erosion rates. In the present work, numerical investigation of the erosion of a pipe protruded in a sudden contraction is presented. The turbulent, steady, 2-D axi-symmetric flow inside an axi-symmetric abrupt contraction pipe with a pipe protrusion embedded in it was solved by steady-state time averaged conservation equations of mass and momentum along with two equation model for turbulence. Particles are tracked using Lagrangian particle tracking. An erosion model was employed to investigate the erosion phenomena for the given geometry. The influence of the different parameters such as the inlet flow velocity (3–10 m/s), the particle diameter (10–400 μm), the protruded pipe geometry (thickness T=1–5 mm and depth H=2–5 mm) and the pipe contraction ratio (Cr=0.25–0.5) on the erosion of pipe protrusion was investigated. Correlations for the influence of inlet flow velocity, depth and thickness of the protruded pipe on the erosion rate are presented. 相似文献
7.
简述了冷轧带肋钢筋的生产工艺及性能。4种不同管径的砼排水管按等强度设计原则,以冷轧带助钢筋替代原用的冷拔低碳钢丝后,可节省钢材10%~31%,并提高砼排水管的裂缝荷载,破坏荷载等质量指标和安全度。 相似文献
8.
S. R. Reid T. X. Yu J. L. Yang G. G. Corbett 《International Journal of Impact Engineering》1996,18(7-8)
This paper is concerned with the problem of pipe whip, the dynamic response of a high pressure piping system subjected to an end force as the result of a pipe break which releases a jet of fluid from the broken section. Both experimental and theoretical results are presented concerning the dynamic elastic-plastic behaviour of cantilever pipes subjected to a transverse force pulse at the free end. Comparisons between experimental data and theoretical predictions are made for mild-steel pipes with outer diameter-to-thickness ratios of 19.5, 28 and 32. It is demonstrated that, for these geometries, the whipping pipes display three characteristically different responses, viz. elastic, plastic hardening behaviour for thick pipes, elastic, plastic hardening-softening behaviour for moderately thick pipes and elastic, plastic hardening-softening-collapse behaviour for thinner pipes. The experimental data taken from a series of high-speed films are compared with the predictions of the instantaneous shapes of the whipping pipes derived from both a rigid, perfectly-plastic, large deflection, dynamic beam model and a more comprehensive model which incorporates the effects of elasticity and plastic hardening and softening, the details of which are presented in the paper. 相似文献
9.
无损检测的几个热点问题和技术 总被引:5,自引:0,他引:5
介绍当前无损检测领域几项快速发展的并受人普遍关注的热点问题和技术,如输油、输气管道和地下管网的在线监测、复合材料粘接层的检测、成像技术以及信号处理。介绍其基本原理、技术特点和近期进展。最后指出,当前新材料新领域的质量控制发展对无损检测技术提出了更高的要求和更广阔的应用空间。 相似文献
10.
小径管焊缝射线照相标准的实践与问题研讨 总被引:5,自引:1,他引:5
通过分析小径管焊缝射线检验中存在问题,对X射线检测标准作了进一步探讨。 相似文献