压力管道基本知识

介绍了压力管道的分类,当前国内压力管道概况,压力管道行政许可法律依据,压力管道设计、压力管道安装、压力管道元件制造的行政许可要求和典型压力管道元件。     

气管道中线定位及测量方法研究

各地天然气管道爆炸事故频发,建设数字化管道、开展管道完整性管理的需求愈加强烈,而作为数字化管道和管道完整性管理基础地理信息数据的管道中线数据的采集也成为了重点讨论的话题之一。从管道定位、管道中线测量两个方面分别进行研究,得出了一套管道中线数据的采集方法,并浅谈了在役管道中线数据采集过程中的管道探测要求及测量精度要求,希望能够为在役管道中线数据的采集提供指导。     

PTA装置试车阶段物料管道振动的影响因素浅析

在精对苯二甲酸(PTA)装置试车阶段,物料管道系统会出现管道振动现象,分析管道振动的原因,提出解决措施,并运用CAESAR II分析软件对管道振动进行模拟分析。结果表明:PTA装置试车阶段发生物料管道振动的影响因素主要有物料管道管径配置、设备和管道布置、支吊架的类型、管道与设备共振以及试车流程等;通过管道系统管径匹配与管道布置合理化、选择合适的支吊架类型、消除设备与管道共振、严格按计划执行试车方案等措施,可减弱或消除管道振动;根据计算机软件模拟分析,适当增加限位和导向,提高管道的刚度,控制管道的低阶固有频率,可有效避免管道振动的发生。     

关于石油化工管道焊接质量控制的探索

管道焊接在石油管道安装工程中属于一项关键性的工作，也是最基本的工作，在保证管道安装质量方面起着至关重要的作用。很多石油化工管道都属于含有有毒介质的易爆、易燃的压力管道，整个石油化工管道安装工程的总体质量和管道焊接质量直接挂钩。管道焊接质量的管理和控制非常的复杂，影响管道焊接质量的因素有很多。所以，需要各部门的共同努力才能把管道焊接工作做好，才能使管道焊接质量得到保证，进而使管道安装的质量得到保证。     

油气管道内检测新技术与应用分析

为了确保油气管道运输的安全性,对特殊运输管道结构必须确保有效的检测.由于油气管道的运行,产生的腐蚀程度和管道的变形,需要通过管道的内检测技术了解管道结构的内部情况.检测管道可以通过检测技术确定管道情况,并在检测过程中进行必要的监控.记录管道管状形式,磁场的变化以图像形式呈现.油气管道检测工作人员还可以增加限定管道的实际...     

钢结构模拟在管道应力分析中的应用

管道应力分析与计算是管道设计的基础之一,它研究管道在各种荷载作用下产生的力、力矩和应力,进行管道安全性评价,使设计的管道尽可能经济合理.文章介绍了钢结构模拟在管道应力分析中的应用,并以海上平台火炬放空系统管道为例,应用CAESAR Ⅱ软件比较了单纯管道模型与管道-钢结构复合模型计算结果的差异,为管道应力分析提供有价值的参考.     

长庆油田原油输送管道内腐蚀预测分析

各种管道中水垢腐蚀产物碳酸盐和其他杂质沉积,会对管道形成强腐蚀.为了更好地解决管道内腐蚀问题,运用软件探讨温度、压力、管道直径、二氧化碳分压、管道倾斜角等参数对管道腐蚀速率的影响.结果表明:随着管道直径的增大,管道内的腐蚀程度降低;CO2气体分压的持续增加,对输送管道的腐蚀程度也会不断加重;同层流管道相比,拥塞段管道的腐蚀速率更高.基于以上条件下,对多相流管道相关的腐蚀问题做出详细分析,并且采用腐蚀风险分析方法预测管道可能发生腐蚀的位置.     

石油化工压力管道柔性设计的浅析

管道柔性的好坏通常与管道应力有关,目前对于管道柔性与应力分析问题的研究越来越多。在这一背景下首先阐述了石油化工管道应力分析方法,然后分析了管道应力的设计要求,之后说明了管道应力分析步骤及管道布置调整问题,最后通过几种管道应力分析设计,对石油化工压力管道柔性设计要点进行说明,希望能为相关人员带来一定的启示,提高压力管道的设计与布置水平。     

探析支架在管道防振中的作用

在工业管道中介质运输过程中,管道会因为外力作用下发生振动,管道振动会对设备及其管道本身带来危害。本文通过对于管道振动起因以及防止管道振动的方法上面,来详细解读了支架在管道防振中的作用。     

液化天然气厂管道振动原因分析及对策

流体机械管道振动现象在许多行业经常发生,剧烈的管道振动往往影响生产的正常运行,因此研究管道振动的原因和机理,分析管道减振对策,是非常必要的。研究了引起管道振动的原因和机理,分析了防止管道振动的三方面策略,同时分析了某液化天然气厂管道振动的原因,给出了相应的管道振动减振策略,最后提出了从设计阶段解决管道振动的策略,给出了在役管道振动的解决方法。     

国内甲醇消费市场状况

我国甲醇主要用于甲醛、对苯二甲酸二甲酯、农药、甲基叔丁基醚、醋酸的生产,我国甲醇消费量增长最快的领域将是燃料甲醇、醋酸和甲醛。预计 2005年甲醛对甲醇的需求量为 175万t左右,聚甲醛对甲醇的需求量为 40万t,醋酸需求甲醇为 62万t,甲基叔丁基醚为 46万t左右,甲胺为 30万t,碳酸二甲酯为 11万t,甲烷氯化物为 10万t,甲醇燃料为 80万t,农药为 22万t,对苯二甲酸二甲酯 3 0万t,其他衍生物 27万t。     

国有大型企业购电模式探讨

结合参与直购电试点运行工作体会，针对直购电模式存在的问题，以及中钢集团吉林炭素股份有限公司用电状况进行介绍分析。简单地回顾了直购电模式的形成历史，从直购电的定义、其价格组成、与各方的利益关系以及直购电价格变动对用电企业外购电成本的影响四个方面对直购电模式运行情况进行了简单的阐述和分析，肯定了直购电模式运行为各方创造了综合经济效益。在直购电模式存在问题上，通过对影响用电企业外购电成本的潜在因素、政策性因素和输配电价格形成是否符合完全科学合理的讨论，认为直购电的价格并不是用电企业购进的最低、最合理的唯一电价。同时对未来国有大型企业购电模式给出几点探讨性建议。     

汽车工业用粘接材料的现状与展望

本文按照汽车制造工序介绍国外汽车工业折边用胶粘剂、点焊胶接用胶粘剂、车身密封胶、车身底涂料、窗玻璃用单组份湿气固化型聚氨酯胶粘剂以及纤维增强树脂用结构胶粘剂等主要胶种的最新技术发展动向。讨论了我国汽车工业用胶粘剂的现状和差距，提出几点建议。     

少烟三元乙丙橡胶材料研制

以三元乙丙橡胶(EPDM)为基体材料，三氧化二锑、十溴苯醚为阻燃剂制备了材料配方，试验了三氧化二锑(Sb22O3)、十溴苯醚(DBDPO))配比对材料烟雾和力学性能的影响，测试了材料的氧指数，可见光的透过率，自熄性等。结果表明，DBDPO与EPDM的相容性比较好，Sb2O3的相容性则相对比较差，两者都可以提高材料的阻燃性能。以4045EPDM橡胶为基体材料，当EPDM100g，白炭黑10g，二硫化四甲基秋兰姆(TMTD)2g，ZnO5g，促进剂M1g，硬脂酸2g，硫磺3g，Sb2O3和DBDPO质量比为20．0／40．0，可以获得具有较好力学性能的少烟EPDM橡胶材料。     

Determination of Several Valences of Iron, Arsenic and Antimony, and Selenium in Glass

Methods for the analysis of silicate glasses are described for ferrous iron, for tri- and pentavalent arsenic and antimony when present together, and for selenium as Se^2-, Se°, Se⁴⁺, and Se⁶⁺. Analytical results are presented for FeO in the range 0 to 0.25%; for total As and Sb as tri-oxide, 0.1 to 1.25%; and for total Se, 0.05 to 0.25%. Apparatus for the determination of FeO is described, and a comparison is made of analytical data for FeO versus light transmittance at 1000 and at 1050 mμ for the same glass.     

An overview of rheology in the computer industry

The rheological characterization of a wide variety of materials used in computer hardware is described. The materials and applications presented include liquid crystal polymers for components, solder paste for surface mounting of integrated circuits, screen printable polyimide for dielectric patterns, new photosensitive polyimide to reduce processing steps, hot-melt adhesive for temporary bonding, pressure-sensitive adhesive for permanent bonding of potical recording disks, bearing grease for magnetic recording disk drive spindles, fluoropolymer lubricants for magnetic recording disks, magnetic particle suspensions for magnetic tape and disks, toner for laser printing, thermoplastic polymer for rapid prototyping, and cathode paste for rechargeable lithium batteries. Rheological tests appropriate for each of the materials were designed to provide key information about its performance in the intended application. This overview provides insight into the relation between interpretation of rheological test data and materials performance in engineering applications as well as for process control. Rheology is essential to the development of computer hardware and peripheral devices. © 1996 John Wiley & Sons, Inc.     

FULLY DEVELOPED LAMINAR FLOW IN A HELICALLY COILED TUBE OF FINITE PITCH

Solutions for steady, fully developed, laminar flow of an incompressible Newtonian fluid through a helically coiled tube of finite pitch were obtained by finite difference calculations. Prior theoretical solutions have apparently been limited to toroidal flow (with zero pitch). The computed results are consistent with those for this limiting case and with prior experimental data for finite pitch. The behavior for helical coils is intermediate between that for a straight pipe and a torus, and, for a moderate degree of pitch differs only slightly from that for a torus. A correlating equation was developed for the friction factor for all Reynolds numbers, all ratios of coil radius to lube radius and all ratios of pitch to coil radius for which the flow remains laminar.     

Analysis of Gas Centrifuge Cascade for Separation of Multicomponent Isotopes and Optimal Feed Position

Abstract

Analysis of the concentration distribution in a gas centrifuge cascade for separation of multicomponent isotope mixtures is different from that in a cascade for separation of two-component mixtures. This paper presents the governing equations for a multicomponent isotope separation cascade. Numerically predicted separation factors for the gas centrifuge cascade agree well with the experimental data. A theoretical optimal feed position is derived for a short square cascade for a two-component mixture in a close-separation case. The optimal feed position for a gas centrifuge cascade for separation of multicomponent mixture is discussed.     

国际海事组织(IMO)涂层技术标准动态

详细介绍了国际海事组织(IMO)近年来制定的有关涂层的技术标准,即压载舱涂层性能标准、空舱涂层性能标准、涂层维护修理指南、永久检验通道(PMA)的涂层/防腐要求、油船货油舱涂层性能标准,为执行标准及制定防腐措施提供了依据。     

Füllstand- und Durchflußmessung in verfahrenstechnischen Anlagen

Measurement of Level and Flow in Processing Plants The author reviews the processes and systems for the measurement of level. The devices are described for indicating the states ?Full”? and ?Empty”? in the automatic charging and discharging, for continuous measurement in the monitoring of the stores and processes, for measuring systems based on specific properties, such as conductivity and capacity, for electromechanical systems, for non-contact measuring procedures based on sonic and ultrasonic echometry as well as radioactivity, for microwave systems, and for the measurement of aggressive products and substances under high pressures and temperatures, and, in explosion-proof plants. In the measurement of flow, inductive flowmeters of high precision and reliability are used for conducting liquids; corrosion-resistant turbines are used for all products with low viscosity; tooth wheel flowmeter are used for highly viscous materials. The processes for the measurement of level and flow are described in an example for the treatment of waste water.