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591.
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压力容器根据各自的特点和在生产工艺流程中的作用 ,都有其特定的操作程序和操作方法。尽管各种压力容器的使用工况不尽一致 ,却有共同的安全操作要点。从操作的角度 ,说明如何预防安全事故。 相似文献
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This work aimed to experimentally evaluate the effects of a carbon monoxide-dominant gas mixture on the explosion characteristics of methane in air and report the results of an experimental study on explosion pressure measurement in closed vessel deflagration for a carbon monoxide-dominant gas mixture over its entire flammable range. Experiments were performed in a 20-L spherical explosion tank with a quartz glass window 110 mm in diameter using an electric spark (1 J) as the ignition source. All experiments were conducted at room temperature and at ambient pressure, with a relative humidity ranging from 52 to 73%. The peak explosion pressure (Pmax), maximum pressure rise rate ((dp/dt)max), and gas deflagration index (KG) were observed and analyzed. The flame propagation behavior in the initial stage was recorded using a high-speed camera. The spherical outward flame front was determined on the basis of a canny method, from which the maximum flame propagation speed (Sn) was calculated. The results indicated that the existence of the mixture had a significant effect on the flame propagation of CH4-air and increased its explosion risk. As the volume fraction of the mixed gas increases, the Pmax, (dp/dt)max, KG and Sn of the fuel-lean CH4-air mixture (7% CH4-air mixture) increase nonlinearly. In contrast, addition of the mixed gas negatively affected the fuel-rich mixture (11% CH4-air mixture), exhibiting a decreasing trend. Under stoichiometric conditions (9.5% CH4-air mixture), the mixed gas slightly lowered Pmax, (dp/dt)max, KG, and Sn. The Pmax of CH4-air mixtures at volume fractions of 7%, 9.5%, and 11% were 5.4, 6.9, and 6.8 bar, respectively. The Sn of CH4-air mixtures at volume fractions of 7%, 9.5%, and 11% were 1.2 m/s, 2.0 m/s, and 1.8 m/s, respectively. The outcome of the study is comprehensive data that quantify the dependency of explosion severity parameters on the gas concentration. In the storage and transportation of flammable gases, the information is required to quantify the potential severity of an explosion, design vessels able to withstand an explosion and design explosion safety measures for installations handling this gas. 相似文献
595.
《International Journal of Sustainable Engineering》2013,6(2):145-152
The demand for petroleum products in India has been increasing at a rate higher than the increase of domestic availability. At the same time, there is continuous pressure on emission control through periodically tightened regulations particularly in metropolitan cities. In the wake of this situation, there is an urgent need to promote the use of alternative fuels as substitutes for high-speed diesel. Dual-fuel mode of operation employing compressed natural gas (CNG) and plant oils such as Honge and Jatropha oils and their esters is an attractive option as our country has a large agriculture base that can be a feedstock to this fuel technology which can ease the burden on the economy by curtailing fuel imports. This paper presents the results of investigations carried out in studying the behaviour of Honge and Jatropha oil methyl esters and their blends with 15% ethanol and subsequent testing of these oils in a four-stroke, single-cylinder, water-cooled, direct-injection compression ignition engine in dual-fuel mode with CNG induction. 相似文献
596.
Cameron “Dale” Bass Martin Davis Mark “Steve” Rountree Robert M. Harris Ellory Sanderson 《International journal of occupational safety and ergonomics》2013,19(4):347-361
To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.567 kg of spherical C-4 explosives to determine the level of protection offered to the head, neck, and thorax.A Hybrid III dummy, an instrumented human surrogate [1], was tested with and without protection from the 4 commercially available bomb suits. 20 tests with the dummy torso mounted to simulate a kneeling position were performed to confirm repeatability and robustness of the dummies, as well as to evaluate the 4 suits. Correlations between injury risk assessments based on past human or animal injury model data and various parameters such as bomb suit mass, projected area, and dummy coverage area were drawn. 相似文献
597.
为提高低透突出煤层的瓦斯抽采效果,在薛湖煤矿2303风巷进行了深孔水力致裂与潜孔抽采联合消突技术的试验应用.首先结合现场实际情况,从注水压力、钻孔布置和现场施工等方面研究了施工技术工艺,然后从应力分布、瓦斯解吸速度、钻屑瓦斯解吸指标、瓦斯抽采浓度等方面考察了水力致裂增透效果和联合消突技术的消突效果.应用表明,深孔水力致裂增透与浅孔抽采联合消突技术,工作面前方支承压力、瓦斯解吸速度、钻屑瓦斯解吸指标均大幅降低,瓦斯抽采浓度明显提高,抽采效果明显,为同类矿井的防突工作提供了可借鉴的技术和经验. 相似文献
598.
成志钢 《中国特种设备安全》2013,(12):1-3
运用有限元分析软件,分析了不同的自紧压力对车用玻璃纤维环向缠绕气瓶疲劳性能的影响,采用新的许用应力幅度一循环次数曲线代替JB4752,对不同自紧压力下的疲劳寿命进行了计算,认为不经过自紧只打水压试验是无法满足气瓶疲劳试验要求的。 相似文献
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为了研究墨粉在爆炸泄压过程中燃烧与流动的变化机制,通过改变泄爆片尺寸、墨粉浓度以及泄爆片的惯性力等参数对爆炸泄放过程中反应釜中压力以及外场火焰形态变化进行试验研究,同时与完全封闭空间内不同墨粉浓度的压力曲线对比。研究结果表明:相同泄爆开口尺寸下,粉尘浓度与受控爆炸压力(采用爆炸泄压保护措施后工业腔体内产生的压力)负相关;开口尺寸增加可以提升泄压效率;结合外场火焰形态的变化情况揭示声动火焰不稳定性对反应釜中压力发展的影响;通过无惯性泄爆试验的对比证明泄爆片惯性对受控爆炸压力的影响不可忽视。 相似文献