锅炉房蒸汽阀门可能产生的缺陷及其危害

蒸汽阀门不是指内螺纹联接的小型阀门特指规格≥DN150mm的法兰蒸汽阀门，包括截止阀、单向阀和闸阀等。     

阀体强度计算比较与分析

以我厂设计的DN300；PN25闸阀的铸造阀体为例，应用我厂、美国、原西德等国有关强度计算标准进行对比性计算，加以分析，证明了尽管计算方法有一定的差别，但结果基本一致。     

中小型常用闸阀采取液控缓闭装置的设想

中小型常用闸阀采取液控缓闭装置的设想目的,是想解决常用闸阀在开启工作后,因故电源突然中断,工作机械失去动力(如水泵),管路中的液体失去动力源将会快速倒流,安装于管路的闸阀在无操作电源时能实现两阶段关闭,即停电瞬间闸阀快速关闭2/3,余1/3缓慢关闭,既避免流体快速倒流损坏工作设备和动力设备;又避免快速关断水流发生水锤现象。实现用液控缓闭闸阀代替常用闸阀和缓闭蝶阀或逆止阀的目的。     

闸阀阀座外压分析

本文介绍了闸阀阀座受外压作用的概念,并使用应力分析设计方法对闸阀阀座进行了应力强度校核。     

国内信息

上海冶金矿山机械厂设计制造的大型电除尘器,最近获得国家重大技术装备成果奖。作为我国第一台为60万千瓦发电机组配套的大型电除尘器,其国产化率已高达95%。上海冶金矿山机械厂为平圩电厂60万千瓦火力发电机组配套生产的225平方米电除尘器,于1990年11月通过部级鉴定。最近,为引进型60万千瓦配套的225平方米电     

元坝气田井口装置平板闸阀故障分析及对策研究

元坝气田为国内第二大高酸性气田,具有气藏埋藏深、硫化氢含量高以及地层压力高等特点,目前气田气井井口采用的是抗硫级别为HH级、压力级别为105MPa的采气树,但投产3年以来,井口装置平板闸阀仍出现一系列故障,给气田井控工作的正常开展带来了挑战。以井口装置平板闸阀为研究对象,统计可知气田井口装置平板闸阀常见故障主要包括外漏、开关不灵活、内漏以及开关不到位。结合闸阀设计机理、外部条件以及人为因素,分析得到造成平板闸阀故障的原因主要有密封组件失效、轴承以及销钉损毁、阀板材质疏松或杂质引起密封不严等。针对井口装置阀门故障以及故障原因,提出更换阀门、更换阀门密封件、更换轴承、注脂堵漏以及阀门活动解卡等处置措施;同时提出加强阀门维护保养、保证盘根等易损备件充足以及保持气井合理工作制度等合理建议。     

柱塞阀的结构及其应用

阀门是工业管道上必不可少的组成部分,通常低、中压阀门如截止阀、闸阀等,是根据平面密封的原理设计的。一旦密封面受到损伤或腐蚀,就不能保证很好贴合而产生内漏。而阀盖的填料老化后会造成外泄。泄漏严重时必须更换。因此,这类阀门在制造时,必须提高阀瓣和阀座上密封面的加工精度,在使用时必须经常更换填料和整修密封面,使成本提高,维修量增大。柱塞阀采用径向密封原理,它以不锈钢     

关于推荐2017年工业节能与绿色发展重点信贷项目的通知

各省、自治区、直辖市及计划单列市、新疆生产建设兵团工业和信息化主管部门,国家开发银行各分行,有关中央企业: 为贯彻落实《中国制造2025》(国发〔2015〕28号)、《工业绿色发展规划(2016-2020年)》(工信部规〔2016〕225号),根据《工业和信息化部 国家开发银行共同推动"中国制造2025"战略合作协议》,工业和信息化部、国家开发银行将联合开展2017年工业节能与绿色发展重点信贷项目推荐工作.     

给水泵站水泵调速的节能分析

分析了给水泵站中水泵调速的节能原理，并以闸阀调节做为对比方案，提出了水泵调速节能的计算方法。     

不同形式和管径的地埋管换热器换热性能分析

结合岩土热响应试验,对岩土初始平均温度和综合导热系数的不同获取方法进行对比分析,结果表明无功循环平均温度及现场热响应试验得出导热系数值作为系统设计参数更为接近实际工况。分析对比不同埋管形式、不同管径的地埋管换热器换热性能,换热器采用单U形式时,DN40管较DN32管的换热性能提高约30%;不同换热器形式,DN32双U管换热性能较单U管提高约80%;DN32双U换热器的换热能力较单U40提高近40%。DN32双U换热器的换热能力远远优于其单U换热器和DN40单U换热器,可作为实际工程中优先选用的埋管形式。     

加氢裂化装置液力透平机械密封系统改造

2008年2～7月,燕山石化炼油一厂液力透平机械密封系统发生5次泄漏.对其进行改造:密封内部结构,将双端面机械密封由旋转式改为静止式;用小弹簧取代波纹管,密封“O”形圈选用全氟醚橡胶(FFKM);动、静环材料升级为复合型碳化硅,提高了导热性能;将密封动环的镶嵌式结构改为整体加工结构,密封静环几何形状最大限度地保证了温度的均匀变化;缩小密封面宽度,以减少摩擦产生的热量;将泵送环由螺旋型更换为离心式,以增加隔离液的循环流量.密封辅助系统,在靠近大气侧的第二道密封外部通入保护氮气,防止泄漏出的少量高温隔离液与空气中的氧气接触产生积碳;氮气经过滤、减压后,用紫铜管引入密封腔体内.冷却水改造,将软化水引至液力透平,既可替代原有循环水,又无需增加额外的软化水消耗.软化水的使用,消除了隔离液冷却器盘管外部结垢隐患.改造后,液力透平的同步运行率由53.2％提高到98.0％.每年节电1.94× 106kW.h,节约资金136万元.     

Experimental analysis of pyrolysis of sewage sludge

Pyrolysis is a thermal process where organic materials such as biomass and oil are decomposed and lighter materials such as gas, vapor, liquid products, and char are produced. The aim of this study was to investigate the pyrolysis behavior of sewage sludge in different operating conditions. Using a fixed bed, the influence of some important parameters such as pyrolysis temperature, heating rate, particle size, and N₂ flow rate on product yields was studied. Results showed that with increase in temperature from 400 to 700°C, the char yield decreased from 30.1 to 7.50%, while the gas yield increased from 35.8 to 52.4%. The gas yield also increased from 46.9 to 49.1% as the heating rate increased from 20 to 60°C/s, while the oil yield increased from 45.2 to 46.8% as heating rate increased to 40°C/s and then the increase leveled off.     

煤的燃料(火用)分析

作为重要的一次能源,对煤的燃料(火用)进行分析以确定其最大做功能力,具有重要的理论和现实意义.通过对有关专家研究的总结和分析,认为Rant对燃料(火用)的估算方法既具有科学性,又与实际情况相符.根据电与(火用)的等效性,用发电能力来反映燃料的做功能力,使得基于第二定律的统计更加有效,并能准确揭示其潜力的大小.     

Efficiency of thermochemical production of hydrogen

The overall thermal efficiency of several processes in the chemical industry is calculated from production units. The individual efficiency of a step was found to be 80% or less. Assuming an average thermal efficiency for each step to be 70%. the overall efficiency of two-, three- and four-step processes are estimated to be 50, 35 and 25%, respectively. Extrapolation of these results to the thermochemical decomposition of water leads to the conclusion that the process must consist of three steps or less in order for its efficiency to exceed that of electrolysis.     

机车车轮多轴疲劳强度安全评定的研究

使用ANSYS8.0软件对高速列车车轮进行了三维有限元分析,计算出车轮在直线、曲线和道岔条件下牵引、制动共6种工况时孔边薄弱部位的应力,分别通过Mises等效平均应力方法、Sines平均主应力方法和应力分量中考虑平均应力方法计算出应力在极值位置时的等效应力幅、等效平均应力,从而进一步算出车轮的安全系数,对其疲劳强度进行评定,并对3种方法进行了比较研究。     

Recommendations for implementation of energy strategy of the Republic of Croatia

The Energy Strategy of the Republic of Croatia was adopted by the Croatian Parliament in 2009 for the period until 2020 in order to harmonize national energy goals with goals and time framework of strategic documents of the European Union. The adoption of the Energy Strategy Implementation Program with associated measures is still in process. The goal of the Strategy was to create sustainable energy system that will make a balanced contribution to the security of energy supply, competitiveness and environmental protection in Croatia. In this paper an overview of the energy production, final energy consumption and planned development of energy infrastructure is given. The intention of the paper was to research and stress out the abilities and opportunities of Croatian energy system and to give recommendations for Energy Strategy implementation and practical realization of planned energy infrastructure projects for improvement of security of energy supply and competitiveness of energy system of the Republic of Croatia.     

Achievements of the EC network of excellence HySafe

In many areas European research has been largely fragmented. To support the required integration and to focus and coordinate related research efforts the European Commission created a new instrument, the Networks of Excellences (NoEs). The goal of the NoE HySafe has been to provide the basis to facilitate the safe introduction of hydrogen as an energy carrier by removing the safety related obstacles.The prioritisation of the HySafe internal project activities was based on a phenomena identification and ranking exercise (PIRT) and expert interviews. The identified research headlines were “Releases in (partially) confined areas”, “Mitigation” and “Quantitative Risk Assessment”. Along these headlines existing or planned research work was re-orientated and slightly modified, to build up three large internal research projects “InsHyde”, “HyTunnel”, and “HyQRA”. In InsHyde realistic indoor hydrogen leaks and associated hazards have been investigated to provide recommendations for the safe use of indoor hydrogen systems including mitigation and detection means. The appropriateness of available regulations, codes and standards (RCS) has been assessed. Experimental and numerical work was conducted to benchmark simulation tools and to evaluate the related recommendations. HyTunnel contributed to the understanding of the nature of the hazards posed by hydrogen vehicles inside tunnels and its relative severity compared to other fuels. In HyQRA quantitative risk assessment strategies were applied to relevant scenarios in a hydrogen refuelling station and the performance was compared to derive also recommendations.The integration process was supported by common activities like a series of workshops and benchmarks related to experimental and numerical work. The networks research tools were categorised and published in online catalogues. Important integration success was provided by commonly setting up the International Conference on Hydrogen Safety, the first academic education related to hydrogen safety and the Hydrogen Safety Handbook. Finally, the network founded the International Association for Hydrogen Safety, which opens the future networking to all interested parties on an international level.     

塔里木河流域上游径流变化特征分析

基于塔里木河上游阿拉尔水文站1958~2007年的年径流量资料,采用累积滤波器、Kendall秩次相关检验和小波分析三种方法分析了气候变化背景下塔里木河上游的径流变化特征。结果表明,近50年来塔里木河上游年径流量呈微弱下降趋势,表现为6年和14年的周期变化;而受气候变化影响的近27年年径流量变化趋势趋于平稳,表现为6年和10年的震荡周期,可预测未来一段时间内塔里木河上游将处于一个由偏丰逐渐向偏枯转变的阶段。     

炼化企业污水回用膜污染原因分析

随着我国水资源危机的不断加剧,多数炼化企业新建、改扩建时不能增加用水指标,急需实施节水减排措施。炼化污水的回用,是企业节水减排的重要措施。目前,许多炼化企业采用双膜处理工艺,将污水深度处理后,最大限度实现污水回用。锦西石化污水回用装置采用双膜法进行处理,污水回用项目采用污水处理后达标排放的炼油污水作为原水,通过动态砂滤过滤单元、纤维球过滤单元、超滤单元、反渗透单元,进行炼化污水回用处理。结合锦西石化污水深度处理与回用的工程案例,进行膜污染原因分析。通过水质分析、污染膜片表面形态分析与污染物元素分析,确定了膜污染物的主要成分为有机物,膜污染发生的原因为微生物滋生引起的有机物污染。提出锦西石化污水回用膜污染、堵塞问题的解决方案:在超滤前投加NaClO等杀菌剂,且保证一定的余氯含量,预防膜的生物污染。同时,在反渗透前投加适当富裕量的NaHSO3,防止氧化剂对反渗透膜的破坏,有效预防微生物污染。     

加氢裂化装置高压空冷器风机的改造

某石化公司150×10^4t／a加氢裂化装置高压空冷器风机风量小,叶片和翼型存在缺陷．传动方式效率低,导致高压分离器温度上升,气相循环氢体积增大,相应增大了循环氢压缩机负荷,造成汽轮机蒸汽耗量增加,循环氢纯度降低,产品质量变差。对高压空冷器4台风机实施了改造：采用新型HY系列玻璃钢叶片替换TB型铝风机叶片．采用啮合传动型的同步带传动替换摩擦传动型的多楔带传动。与改造前相比,改造后风机全压从170Pa提高到200Pa,风量从36×10^4m^3／h提高到46×10^4m^3／h,平均风速从3．391m／s提高到3．875m／s;反应流出物的温降提高了5℃;汽轮机3．5MPa蒸汽消耗量每小时可节约0．6t;加氢裂化装置运行平稳。加工量从149．44t／h提高到164．75t／h。