制索机上的光电控制装置

在导火索生产中,一台制索机需一名工人看守,其精力需百倍集中,否则就发现不了断芯线。由于断芯线一根不超过两米列为次品,断芯线二根以上均为废品,因而会因断芯线没有发现,造成几米、几十米,甚至上百米的成品报废。在制索机上安装光电控制装置,当芯线断了,制索机立即自动停车,可以减轻工人的负担,减少废品,还为机车全面实现自动化控制创造条件。     

能量输出交替变化的双芯导爆索的制法

本发明论述了一种双药芯复合导爆索的制造方法,其药芯能量能在可控范围内变化。这种导爆索专门用于金属扩张中。导爆索可用干法或湿法制造。干法生产的导爆索的芯药由干燥得比较粗的药粒组成,用带状包缠物封闭成连续的药柱,外绕棉纱,再用沥青、热塑性塑料或类似的防水层包覆。干法通常用于制造每英尺药芯药量等于或大于25格令的导爆索。湿法的药芯由粒状炸药的稠密浆液组成,用织物编成的织带包缠,再以和干法相同的方式包覆。一般     

导火索断细药的气动法检测和自控停车装置

导火索断细药的存在常使导火索的性能变劣,给使用导火索造成危害。因此,在生产中如何及时发现导火索的断细药是一个急需解决的重大课题。多年来,各厂进行了大量地试验研究工作,且有不同程度的进展。 (一)机械检验法机械检验法系在内层线包缠药芯之后的部位采用滚轮对挤的形式检测断细药。这种装置要求制作和安装的精度都较高,但还不能直接     

红外光谱分析在银导爆索热处理工艺中的应用

银导爆索在拉制过程中会产生冷作硬化而易断裂,需经过高温处理软化银索,但其内装填聚奥炸药在受热后易出现晶型转变,影响产品性能.为避免银导爆索热处理拉制过程中出现断索及内装炸药转晶现象,借助烘箱模拟导爆索拉制过程的退火及回火热效应,应用红外光谱分析技术,分析原始炸药及导爆索内解剖炸药晶型结构,进行导爆索热处理工艺参数制定.结果表明,某银导爆索在130℃下,累计保温7h以内,其内装聚奥炸药未发生晶型转变,拉索安全且不易断裂.     

隧洞开挖光面爆破装药结构的改进与应用

为了解决乌干达卡鲁玛尾水隧洞光面爆破施工中,无专用光爆细药卷(φ20~22mm),且竹片难于买到,无法绑扎光爆药串等问题,在8#、9#、10#支洞及主洞开挖爆破施工中做了一系列光面爆破装药结构改进实验。采用(φ25~32mm)常规药卷,在其未与导爆索绑扎的条件下,导爆索成功起爆了光爆孔内按设计线装药密度装入的间隔装药,且取得了理想的光爆效果。实验及应用情况表明:在φ42mm光爆孔内,导爆索与一定间距(50cm)的间隔装药在孔内自由分布、未绑扎的条件下,导爆索完全能够起爆孔内的间隔装药,这就简化了传统的光爆药串加工工艺,改变了隧洞开挖中传统的光爆孔内装药结构。     

两种装药条件下扩爆管输出威力的因素试验研究

在金属导爆索爆炸网络中,细导爆索可作为延期体,使用被细导爆索起爆的扩爆管可扩大该网络的爆轰输出.在扩爆管内分别使用A5和钝化RDX装药,研究了两种不同装药扩爆管的装药量、装药压力、装药层数和起爆用金属导爆索等因素对其输出威力的影响.实验结果发现,两种扩爆管在以上的因素里有较好的一致性,得出了A5和钝化RDX装药的扩爆管的合适装药结构为:一层装药量为600mg,装药压力为52.02 MPa时,用φ3.0 mm的金属导爆索起爆的结论.     

一种使用连接块的硐室爆破可复式网路

在硐室大爆破中,以前常用的起爆网路是电起爆和导爆索起爆。近年来也有用塑料导爆管网路的,在采用该网路时,为保证安全可靠,一般都用复式网路,即每个药室中有两     

隧洞开挖光面爆破装药结构的改进与应用

为了解决乌干达卡鲁玛尾水隧洞光面爆破施工中,无专用光爆细药卷(φ20²2mm),且竹片难于买到,无法绑扎光爆药串等问题,在8#、9#、10#支洞及主洞开挖爆破施工中做了一系列光面爆破装药结构改进实验。采用(φ2522mm),且竹片难于买到,无法绑扎光爆药串等问题,在8#、9#、10#支洞及主洞开挖爆破施工中做了一系列光面爆破装药结构改进实验。采用(φ25³2mm)常规药卷,在其未与导爆索绑扎的条件下,导爆索成功起爆了光爆孔内按设计线装药密度装入的间隔装药,且取得了理想的光爆效果。实验及应用情况表明:在φ42mm光爆孔内,导爆索与一定间距(>50cm)的间隔装药在孔内自由分布、未绑扎的条件下,导爆索完全能够起爆孔内的间隔装药,这就简化了传统的光爆药串加工工艺,改变了隧洞开挖中传统的光爆孔内装药结构。     

纸包药塑料导爆索

纸包药塑料导爆索是索类火工品中的新产品,在技术性能及使用条件上不亚于通用的棉纱型导爆索,它同样适应于无瓦斯、煤尘及矿尘爆炸危险的爆破作业。当引爆药包群时,比棉纱导爆索效果更好。     

导火索断细药自动报警装置

1 概述工业导火索制造时断、细药时常发生,如何进行控制与检测是生产中要解决的主要问题。我厂自1970年生产工业导火索以来,几乎每年因断、细药而报废的工业导火索就达     

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.     

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.     

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...     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

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.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...