关于高温凝结物的爆破实践

详细描述了冶炼炉内高温凝结物爆破拆除施工工艺。提出炉内喷水强制降温,爆破前测量高温炉内炮孔温度,找出炮孔温度随时间的变化规律,采用隔热药包,确保孔内药包在规定时间内温度不大于60℃。通过对宁夏平罗、惠农等地区铁合金冶炼炉400余次炉内高温凝结物的成功爆破清除验证了施工工艺的正确性。     

炼硅炉沉渣爆破拆除

高温条件下炼硅炉内的沉渣进行爆破清除,具有一定的特殊性和难度。通过试验选择了适合高温条件下的起爆方法和网路设计,并对爆破器材采取了有效的降温措施,确保安全起爆,并分层定量地进行了多次爆破,成功地完成了爆破除渣任务。     

高温磷炉炉瘤爆破施工与安全控制

介绍了黄磷电炉采用爆破法清除炉瘤的技术和经验。包括爆破方案与参数、施工前的炉内通风及降温处理、高温条件下的装药和起爆工艺、磷炉高温爆破危险有害因素分析和爆破安全控制措施。可供同类爆破项目参考。     

高温磷炉炉瘤爆破施工与安全控制

介绍了黄磷电炉采用爆破法清除炉瘤的技术和经验。包括爆破方案与参数、施工前的炉内通风及降温处理、高温条件下的装药和起爆工艺、磷炉高温爆破危险有害因素分析和爆破安全控制措施。可供同类爆破项目参考。     

大型炼铁高炉炉结的高温控制爆破技术研究

介绍了某大型炼铁高炉的炉结在高温下控制爆破清除的成功经验。在试验和实测的基础上,着重研究了高温控制爆破过程中容易出现安全问题的爆破器材的隔热保护、起爆网路的可靠性和爆破产生的振动冲击的控制。通过选择合理的爆破方案、适宜的爆破器材、新型的隔热材料、优化的爆破参数和可靠的起爆网路,实现了高温(500℃)下炉结的快速(7d)清除。     

大型炼铁高炉炉结的高温控制爆破技术研究

介绍了某大型炼铁高炉的炉结在高温下控制爆破清除的成功经验.在试验和实测的基础上,着重研究了高温控制爆破过程中容易出现安全问题的爆破器材的隔热保护、起爆网路的可靠性和爆破产生的振动冲击的控制.通过选择合理的爆破方案、适宜的爆破器材、新型的隔热材料、优化的爆破参数和可靠的起爆网路,实现了高温(500℃)下炉结的快速(7d)...     

高温爆破中不可逆起爆网路的应用研究

为了避免高温爆破早爆事故的扩大升级,对不可逆起爆网路进行了研究和分析。首先,分析高温爆破作业安全对起爆网路的功能要求,提出并定义了不可逆起爆网路;其次,通过起爆网路器材选型和起爆网路传爆属性分析,优选并推荐使用"四通连接大把抓复式起爆网路"和"雷管孔外接力逐孔起爆网路"两种不可逆起爆网路;最后,合理应用不可逆起爆网路,将爆破工艺流程中的警戒和联网工序前置,缩短爆破器材在高温炮孔中的留置时间。实践表明:不可逆起爆网路能够有效避免高温爆破早爆事故的扩大升级,有利于灾后盲炮的处理。     

高温金属炉渣控制爆破技术研究与实践同温

根据高温金属炉渣硬度高、难以穿孔、作业风险大等爆破难点,采取用氧气吹炮孔的方式由外向内穿孔,运用不间断的冷却水降温法控制炉内温度.在爆破作业过程中,爆破装药外壳增加耐热石棉布、每次起采用电起爆法起爆1个药包、每次作业时间不超过1 min等措施控制装药内部温度确保了作业安全.同时对爆破施工组织与安全防护方面进行了论述,提...     

高温闪速炉炉结爆破拆除

叙述对吹炼炉炉结高温凝结物的爆破拆除.施工与安全防护.重点分析了在保证不停产情况下对炉结进行爆破,如何对炸药雷管有效实施隔热,以保证爆破能顺利进行.从实践中找到了解决的方法,确保了爆破安全,圆满完成了爆破任务.     

起爆方式对岩石柱状装药爆破作用的影响

为提高炸药的能量利用率,改善岩石爆破的破碎效果,以及在柱状装药条件下选择最佳的起爆方式,通过单炮孔混凝土爆破实验研究了不同起爆方式对岩石柱状装药爆破作用的影响。对不同起爆方式下岩石的裂纹扩展和破碎效果进行了分析,并利用有限元分析软件ANSYS/LS-DYNA建立单炮孔岩石爆破损伤模型,对不同起爆方式下岩石损伤过程进行了数值模拟。其结果表明:不同起爆方式对岩石爆破破碎作用影响较大,反向起爆相对于正向起爆和炮孔中部起爆在岩石表面产生的裂纹条数更多,裂纹扩展速度更快,岩石破碎程度更好;数值模拟结果和实验结果具有较好的吻合性,对起爆技术的改进和起爆方式在工程应用上的选择具有一定的指导意义。     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.     

Evaluation of fatigue life of steel using steel grain size

The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.