机械起爆引信改装方法及传爆能力分析

为解决机械起爆引信失效率高的问题,探索出一种保留传爆序列的起爆引信改装方法和解除保险方法。运用Autodyn软件仿真分析工业8号雷管在空气中爆炸的冲击波超压,发现在距离雷管端面2 mm内的空气冲击波超压大幅下降,要引爆不保留传爆序列(只含传爆药)的起爆引信,雷管端面与传爆药的理论最大允许间隙约为0.33 mm。分别对保留传爆序列和不保留传爆序列2种起爆引信进行钢凹试验,设置无间隙和有间隙2种起爆情形,试验结果表明：无间隙起爆时,2种起爆引信的传爆能力相当,钢凹深度分别为1.80 mm和2.08 mm。间隙2 mm起爆时,不保留传爆序列的起爆引信未完全作用,钢板表面无形变;带传爆序列的起爆引信完全作用,钢凹深度2.04 mm。试验结果既印证了仿真分析的准确性,也说明了带传爆序列的起爆引信对雷管端面间隙不敏感,具有很高的传爆可靠性,配合解除保险方法,将显著提高机械起爆引信的作用安全性和有效性。     

射孔弹射孔未穿孔的原因分析

针对近期在四川油气田若干井次的施工中出现不完全射孔的现象进行了分析和试验,找出了射孔施工起爆率不能达到100%的主要影响原因,提出了相应的应对措施:加强射孔弹与射孔枪的匹配设计以避免装配过程导爆索受损,保证导爆索装配完成后处于绷直状态,选择合适感度的传爆药,优化压药工艺,降低传爆药压药密度,严格控制射孔弹装枪质量,提高导爆索本身质量,这些措施对有效提高射孔弹起爆率是很有必要的。     

微序列隔板对MEMS火工品传爆性能的影响?

为研究微传爆序列结构中隔板对其传爆性能影响,采用有限元分析方法,模拟了微小直径药柱(以CL-20和JO-9C作为一级、二级装药,直径分别为2 mm和4 mm,径高比为1)在镍和不锈钢材料下,不同隔板厚度对微序列起爆传爆能力的影响。得到了CL-20起爆JO-9C装药时这两种材料隔板的临界起爆厚度,分别为1.6 mm(不锈钢)、1.4 mm(镍),材料镍的隔爆能力优于不锈钢。对仿真结果进行了试验验证,结果表明,该仿真能够较准确地反映实际情况。     

复杂环境下框剪结构烂尾楼定向爆破拆除

根据框架-剪力墙结构烂尾楼的结构特点,以及周边环境情况,采取"Ⅰ区、Ⅱ区依次向东定向倒塌"的总体爆破方案。由于倒塌空间有限,为减小大楼的倒塌距离,将Ⅰ区的爆破切口提高至5层,Ⅱ区延迟Ⅰ区460 ms起爆。运用LS-DYNA动力学有限元软件,验证了爆破总体方案的合理性,计算得到的倒塌运动过程和堆积形态与实际效果比较吻合。结合现场踏勘情况,对大楼的爆破倒塌效果进行了详细分析,结果表明:采用"分区间隔延时"爆破拆除框剪结构大楼时,合理的爆破切口高度和延期时间是关键;在定向倒塌方案中,为降低爆堆高度,需要对梁结构进行爆破弱化处理。     

高温环境对普通导爆管雷管点火可靠性的影响

采用951-000、112A和Q210 3种粒料拉制普通导爆管,测试不同环境温度条件下的爆速、抗击穿性能,研究不同环境温度下3种粒料拉制的导爆管对钨系、硅系、锑系及硼系延期体的发火可靠性。研究表明:随着温度的升高,3种粒料拉制的导爆管爆速和抗击穿性能均有不同程度下降,其中,951-000的性能优于112A的性能,112A的性能优于Q210的性能。对4类延期体进行发火可靠性测试:温度t≥60℃时,钨系和锑系延期体出现拒爆;t≥70℃时,硼系延期体出现拒爆;t≥80℃时,硅系延期体出现拒爆。且拒爆率均有随着温度升高而增加的趋势。同一类延期体,相同环境温度下,Q210的拒爆率最大,951-000的拒爆率最小。     

格式爆破网路的可靠性计算

本文证明了一组求格式传爆网路上各结点的准爆率的递推计算公式,最后运用这些公式给出一个实例的计算结果。     

基于高速摄影法对孔桩内导爆管准爆的探究

针对贵阳花果园V区孔桩爆破中塑料导爆管多次产生拒爆的实际情况,为降低盲炮的产生、提高准爆率,特对导爆管传爆性能进行研究。首先,利用高速摄像机进行完整导爆管的传爆试验,获得所使用导爆管的稳定爆速为1650 m/s;然后进行切缝试验,得出切缝长度在12 cm以上导爆管将产生断爆,断爆爆速临界值为525 m/s;最后进行注水试验,当注水长度达2 mm必断爆。结果表明:施工误操作破损后的塑料导爆管使用在含水的孔桩内,盲炮率较高,切缝是导致拒爆的诱导因素,注水是主导因素;施工过程中应采取有效措施减少孔内积水及确保导爆管完整无缝隙,防止积水渗入导爆管导致拒爆,可有效降低盲炮率。     

塑料共混改性提高导爆管高温使用性能

文章以目前导爆管的管壁材料低密度聚乙烯塑料为主体,对塑料原料进行物理共混改性.改性后生产成本增加很少,明显提高了导爆管在高温条件下的传爆可靠性,塑料共混后用普通工艺生产的导爆管试验用样品能够在80℃以上高温下正常传爆,从而能够保证导爆管高温条件下使用于爆破网络中的传爆安全.结果表明,塑料共混改性作为新的塑料导爆管的工艺生产方案是经济、有效而且可行的.     

导爆索与导爆管传爆结点可靠性的检测、分析与评价

结合南芬露天矿的实际,运用统计分析的方法,对导爆索与导爆管3种类型的传爆结点可靠性进行抽样测试、分析与计算,初步确定了其3种类型传爆结点的可靠性指标,并对其可靠性进行了评价.     

传爆序列传爆可靠性的研究

本文运用飞片撞击起爆模型,对传爆序列的传爆可靠性进行了研究。并就某引信中的导爆管到传爆管一级的爆轰传递给出了与实际情形相同的计算结果。文中方法可运用到同类型的研究中。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

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.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

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.