海上平台FM200管道设计及喷头布置

为使灭火系统管线设计更合理、规范、科学,本论文结合工程实例,通过对选用七氟丙烷（FM200）气体灭火系统的系统管网布置、喷头布置方式的论述,依据国家和行业现行的有关标准规定,分析了进行工程设计时应考虑的条件、要求以及在设计过程中对不同问题的解决处理方法。     

PLC抗干扰针对性措施研究

PLC应用广泛,但是易受电源、信号线引入、接地系统、变频器等的干扰常造成设备失控与误操作,通过选择抗干扰性能好的设备、强化综合抗干扰设计、优选性能优选的电源、优选电缆及布置方式、加强滤波及软件抗干扰措施、完善接地系统等针对性抗干扰措施,解决了PLC干扰难题。     

水泥厂总降高压电源进线方式的选择

正1水泥厂总降电源进线方式目前水泥厂中60kV及以上总降压变电站高压设备一般都采用GIS,而电源进线方式分为架空进线和电缆进线两种(与GIS连接)。架空进线的特点是:施工简单、投资少、维护方便、可靠性高,但对总降压变电站的布置有一定的要求,且不能深入到负荷中心。电缆进线的特点是:对总降压变电站的布置要求少,能深入到负荷中心,但施工比较复杂,投资多,风险大。2安哥拉5 000t/d项目情况     

探讨塔的布置和配管

本文结合具体实际情况，详细的分析与论述了应用比较广泛的板式塔与填料塔，通过论述露天布置塔的方式，来提出一些布置与配管的建议，希望能够对相关从业人员一些有意义的参考价值与意见。     

大型常减压装置工艺热油泵管道柔性设计研究

介绍了国内大型常减压装置工艺热油泵的管道布置和柔性设计。通过对国内几家常减压装置工艺热油泵的管道布置和柔性设计分析和对比,得到了相对优化的管道布置方式。此方式通过水平延伸布置方式在满足设备管嘴受力以及管道柔性的要求下达到最佳的投资收益比。分析结果表明这种方式的工艺热油泵工程设计是非常成功的。     

干式煤气柜油泵站工艺配管的改进设计

文章介绍了干式煤气柜油泵站油泵进出口传统的工艺管道布置方式,结合相关规范对该布置方式的缺点进行了分析,提出了一种新的管道布置方式。     

LNG接收站气化器选型及其布置要点

气化器系LNG接收站中的重要设施,文中对气化器的不同分类方式进行了简要的介绍。根据现有大型接收站的气化器配备情况,着重介绍了中间介质气化器、开架式气化器和浸没燃烧式气化器的设备结构、特征及其选择时所需关注的重点。结合国家现行规范,列举了设计过程中气化器布置需遵循的原则。并根据实际设计经验,总结了气化器设备布置中的要求、合理的布置方式;总结了气化器相关主工艺管道和海水管道的布置要点及柔性设计方法。     

海洋石油平台管道布置设计与研究

随着海洋资源的开发与利用,对海洋平台管道设计也提出了更高的要求。在进行海洋石油平台管道布置设计时应对不同的影响因素进行充分的、全面的考量,如海洋环境问题、污染问题、安全问题等。通过对以往海洋石油平台管道布置设计情况分析后,可将相关经验进行总结与应用。在进行海洋石油平台管道布置设计工作时专业的设计人员应对建设区域进行深入的了解,在此基础上确定管道位置;在进行管道连接时应根据具体的情况来选择焊接方式,减少安全事故的发生率,以此来控制管道焊接质量,避免出现海洋环境污染的情况。所以,对海洋石油平台管道布置设计进行分析与研究有着重要的意义。     

水泥窑采用SCR脱硝技术的工程应用

分析了水泥窑烟气粉尘的特性及与火电厂粉煤灰差异，介绍了四种常见的水泥窑SCR布置方式。通过四个典型的水泥窑SCR中外实例，详细介绍了不同案例的工艺布置、催化剂设计选型、脱硝效率以及运行成本，探讨了SCR脱硝运行过程中常见问题以及解决办法，并对两种常见布置方式提出了一孔之见。     

非对称布置双鞍座卧式容器的设计计算

对于结构或载荷相对于跨中截面非对称布置的双鞍座卧式容器,因其计算模型与目前标准中的对称布置方式不同,不能套用标准中的计算公式。举例介绍这类容器的受力分析和各项应力的校核。     

Burning behavior of cable tray located on a wall with different cable arrangements

Cable fire risk analysis is important for fire protection design in nuclear power plants, where multiple horizontal cable trays are mostly located on the walls. Fire experiments using three cable trays with different cable arrangements were conducted in a confined room to investigate the burning behavior of a cable tray on a wall. A corner was formed by the side wall and the cable tray. Hot smoke emitted from the burning cable was trapped in the corner and then ignited the cable on the bottom surface of the upper cable tray. It is found that for cables densely packed together, spread of flame on the bottom surface of cable tray was clearly observed and increased the mass loss of cable burning during the growth stage of a cable tray fire. For cables arranged further apart, vertical propagation from the bottom tray to the top tray was fast and dominated the mass loss of cable burning.     

电缆防火涂料阻火有效性试验

根据电缆隧道实际环境,建立电缆水平燃烧试验平台,研究不同火灾荷载和通风速度下,受防火涂料保护电缆延燃长度的变化规律。结果表明:一定风速条件下,电缆延燃长度随敷设宽度增加呈指数增长,可根据隧道内通风速度和电缆束宽度近似预测电缆延燃长度,从而为电缆隧道的防火设计提供依据。     

电线电缆阻燃化研究现状

分析了电线电缆火灾的成因和危害;简要介绍了低烟低卤阻燃聚氯乙烯电线电缆料的发展现状和方向;重点介绍了低烟无卤阻燃聚烯烃电线电缆料的阻燃机理和研究现状;提出了阻燃剂的无卤化、抑烟和低毒是当前和今后电线电缆阻燃研究领域的前沿课题,但在阻燃电缆的应用上还需进一步深入研究。     

船用丁苯橡胶绝缘电力电缆剩余寿命评估

采用实验室加速热老化并结合Arrhenius热老化方程,对船用丁苯橡胶绝缘新电缆的使用寿命进行预测。然后将新电缆实验数据中的性能失效值作为使用中电缆实验性能失效评判标准值,对使用中的丁苯橡胶绝缘电力电缆的剩余寿命进行计算,通过计算两者之差得到使用中电缆的剩余寿命,计算结果基本和实际情况一致。证明了利用该方法对使用中的电缆的剩余寿命进行评估可靠实用,为使用中的电缆预防性更换提供理论和实践依据。     

The effect of accelerated ageing of building wires

The fire performance of two electric cables (building wires) designed for indoor use has been tested, both as new products and after accelerated thermooxidative ageing. The cables were aged for a maximum time of 16.5 weeks at 80°C. The cables are commercially available, and were constructed using a PVC material in one case and a non‐halogenated polyolefin‐based material, called Casico, in the other. The effects of ageing on the fire performance of the cables, and the chemical changes that have caused the observed fire behaviour, have been investigated and are discussed. Special attention is paid to the behaviour of the plasticizers that are used in the PVC cable, and how the fire behaviour is affected by the loss of plasticizers from the cable and by the migration of plasticizers between the parts of the cable (insulation, bedding and sheathing). Copyright © 2007 John Wiley & Sons, Ltd.     

可交联PE电缆用半导电屏蔽料开发现状

综述了可交联聚乙烯(XLPE)电缆用半导电屏蔽料的国内外开发现状,介绍了不同等级XLPE电缆用半导电屏蔽料的原料生产工艺、相关设备、相关标准要求以及国外先进的检验测试方法等,列举了北欧化工公司和美国陶氏化学公司不同等级半导电屏蔽料的牌号和性能。目前,国内只能生产35 kV及以下的电缆屏蔽料,而国外能够生产110 kV及以上电缆屏蔽料。国内开发110 kV以上XLPE电缆屏蔽料是非常有市场前景的。     

电场对水树老化XLPE电缆修复效果的影响

为提高水树老化交联聚乙烯(XLPE)电缆注入式修复效果,研究了在施加不同电场时,水树老化XLPE电缆的注入式修复效果,以获得较好的修复方式。将水树老化后的电缆样本分别在不施加电压、施加直流正极性电压、直流负极性电压以及施加工频交流电压的情况下进行注入式绝缘修复。注入式修复期间,测量4组电缆样本的泄漏电流并对电缆样品切片后进行扫描电子显微镜观测。结果表明,注入式修复时施加电压明显提高了电缆的修复效果,而施加直流正极性电压时,修复液与水反应后的生成物颗粒团聚小,在水树区域分布均匀,注入修复液后4 h水树老化XLPE电缆的泄露电流下降至10μA,修复效果在4组样本中最优。     

Calculation of water ingress in a HV subsea XLPE cable with a layered water barrier sheath system

The main aging mechanism of electrical cables with polymeric electrical insulation is the growth of water trees. Water trees are initiated if the relative humidity (RH) in the electrical insulation is above a critical level. Delaying the water ingress into the electrical insulation system delays the water tree initiation and reduces water tree growth, thus extending the service life of the cable. For a cable without any metallic water barrier, the water ingress can be significantly delayed by the use of an outer sheath material with low water permeability. An even greater delay in the water ingress into the electrical insulation can be achieved using a layered sheath system. To explore the possibilities of a layered sheath system, calculations of water ingress into a typical cable cross section has been performed using a finite element method. The water diffusion and sorption data used in the calculation has been measured for typical cable materials. Calculations have been performed for uniform temperature conditions and for a temperature gradient due to resistive current heating. The time to reach critical humidity levels and stationary humidity levels in the insulation system has been determined for several different arrangements of the sheath system. A sheath system with an outer layer of a material with low water permeability and an inner layer of a material with a high water absorption capacity is shown to give a significant delay of the water ingress into the electrical insulation. For the sheath materials used in this study, there is an optimum distribution of thickness of each layer. The calculations also show that a temperature gradient across the insulation system of a cable in operation gives an advantageous RH profile. With a temperature gradient the equilibrium RH level in parts of the electrical insulation can be lower than the critical value for water tree initiation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Comparison of large-and small-scale heat release tests with electrical cables

A total of 21 electrical cables were made, all with identical construction but differing in the chemical composition of their plastic components, both jacket (or sheath) and insulation. All the compounds used were commercially available materials, but they covered a variety of polymers, both halogenated and non-halogenated. All cables were tested in a large-scale cable tray test, the proposed ASTM D9.21 test, based on the IEEE 1202 or the CSA FT-4 test, modified to measure heat and smoke release in the duct and with a total length of 2.44 m. The peak rate of heat release measured served as an excellent criterion for distinguishing between cables passing and failing the test (the traditional criterion being char length). The average rate of heat released also served to distinguish the two classes of cables. Moreover, cables passing the test tended to release less smoke than those failing the test. The cables were also tested in the IEC 332-3 cable tray test. The small-scale fire test used for the cables was the cone calorimeter, ASTM E 1354. The trends observed in this heat release test were similar to those in the large-scale test. The results indicate that cables with excellent fire performance can be made by using a variety of materials, so that it would seem to follow that it is important to specify fire performance and leave material choice to manufacturers.