一种防止增压器轴承烧损的保护装置

1　问题的提出　　我国机车柴油机安装使用的多是VTC2 5 4系列、ZN2 90系列及ZN310系列增压器。从各型增压器设计原理上已充分考虑到增压器各部件在使用中所有的性能指标基本满足机车牵引运行时的需要 ,如柴油机转速最高和最低时所需的冷却水温、机油润滑压力等等。尤其是转子轴承的润滑方面 ,不仅从油质上有严格限制 ,而且在油压上也有柴油机空转与负载的不同要求 ,其目的就是确保增压器转子轴承必须在一定压力的机油润滑状态中工作。在“内燃机车操作规程”中规定 ,乘务员在起动柴油机前必须闭合 3K ,起动电机带动的起动机油泵 ,单独…     

一起DFH5型机车烟囱喷水的故障分析及处理

1故障现象 中原特钢股份有限公司铁路运输部DFH5型0161号机车一直担当着公司货场的调车任务,虽然已经工作了20多年,状况还算良好.可是最近一段时间却出现了问题,最早出现的现象是起机困难,按下起动按钮经过45 s后柴油机转动但不发火,烟囱有时还有白烟冒出;后来就发展为不仅起机困难,而且在停机2 h以上时,再次起机就从机车烟囱喷水,像是喷泉一样,但时间不长;有时还喷出黑色的油污,沾到驾驶室的玻璃上.这些不正常的现象严重影响了该台机车的正常调车作业.     

HB-1(GD)型轮轨润滑控制器试验位电路的改进

1 问题的提出 机车轮轨润滑控制器是保证机车轮轨润滑系统正常工作的重要组成部分,该控制器设有静止状态下的喷脂试验电路,以便于机车检修时对轮轨润滑系统的试验检查.     

对DF4型机车起动机油泵电动机控制电路的改进建议

1 问题的提出 DF4型机车的废气涡轮增压器是柴油机的重要部件.增压器受工作环境等诸多因素影响较大,其故障率也较高.尤其是DF4型机车在运行中,柴油机发生突然停机情况时,起动机油泵电动机不转,造成机油压力急剧下降.而此时增压器转子仍然惰转,轴承处于高温无油的干摩擦或半干摩擦状态,导致轴承过热,甚至固死,造成临修、机破事故.因此,有必要对现有的起动机油泵电动机的控制电路进行改进.在柴油机突停情况下,起动机油泵电动机能够自动投入运转,保证在增压器转子惰转时对增压器轴承的润滑,从而减少此类增压器故障的发生.     

GK2B型机车柴油机中冷水温高原因分析

GK2B型机车安装使用12V180ZJC型柴油机,正常工作状态下,中冷水温应保持在40～55℃范围内,当温度超过55C时,55C强冷继电器得电使冷却风扇偶合器充油,同时侧百叶打开,风扇转动对中冷水进行强制降温,使其温度回落到55℃以下.若因出现故障而导致中冷水温度持续上升,将无法有效地对空气和机油进行降温,从而影响柴油机的燃烧质量,并加剧柴油机各运动件的磨损,严重的将导致柴油机出现拉缸等大故障.近期以来,我们段运用的GK2B型机车多次出现中冷水温高故障,1001号机车还造成了柴油机拉缸.因此,柴油机在运用过程中,中冷水温一旦出现异常现象,应及早进行分析和处理.     

DFH(5)-G1型油电混合动力内燃机车的研制

介绍了DFH(5)-G1型油电混合动力机车的性能、特点及主要技术参数,分析了机车改造的技术难点.经试验验证,该车各项性能指标满足设计要求,并在节能环保方面进行了成功的探索.     

单独制动阀置制动位机车与车辆立即停止运行的原因分析及对策

1　问题的提出JZ 7型空气制动机在我段DFH5型机车调车作业使用中,曾多次出现当司机操纵单独自动阀(以下简称单阀)手柄由运转位移至制动区,欲使机车单独制动,并使列车缓慢停止运行时,机车制动缸压力瞬间达到与总风缸压力相同,作用阀和分配阀紧急部的排风口大量排风,总风缸和列     

摩擦学故障诊断技术在机车柴油机的应用

介绍了应用摩擦学故障诊断技术，对机车柴油机润滑系统的磨损颗粒和润滑介质分别作了光谱分析和理化性能测试。通过综合研究，能诊断出柴油机曲轴箱窜燃气的故障状态，并可确定其故障发生部位，旨地提高机车柴油机的可靠性。     

ZN270型增压器配装DF7B型机车柴油机性能的改进

介绍了DF7B型机车柴油机增压系统的改进工作,并通过柴油机台架试验等,验证了新型高效ZN270-LSA4型增压器,可有效解决DF7B型机车柴油机夏季排温高、冬季喘振问题.     

DFH5型机车风源系统改进

针对DFH5型机车风源系统供风速度慢、故障率高的问题开展攻关，最终找出问题根源，确立改造方案，通过实施取得了预期的效果，为老型机车实施技术改造提供了依据。     

Strategies for high-performance supercapacitors for HEV

Our paper highlights the role of supercapacitors in hybrid electric vehicles (HEVs), the current response to the worldwide demand for a clean and low fuel-consuming transport. The main strategies for increasing the specific energy of supercapacitors, which are electrochemical energy storage/conversion systems of high-specific power, are discussed, with the focus on electrode material, electrolyte and electrode/electrolyte interface properties. Particular emphasis is given to the use of ionic liquids (IL), which are attracting much attention as green and solvent-free electrolytes, and to the development of high-voltage, IL-based hybrid supercapacitor with high surface area carbon negative electrode and poly(3-methylthiophene) positive. Based on the results of laboratory cells featuring N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide and 1-ethyl-3-methyl-imidazolium bis(trifluoromethanesulfonylimide) ILs, the specific energies of hybrid supercapacitor modules are evaluated and compared to those expected for double-layer carbon supercapacitors displaying the same ILs.     

面向2050年的中国电力发展展望

电力转型是我国能源转型的重要环节。本文基于自主开发的适合我国中长期电力发展的源网荷储协调规划模型,将各类电源、骨干电网、需求侧资源与储能等统筹考虑,在计及相关发展目标与约束条件的情况下进行系统整体优化,求解了我国当前至2050年电力系统发展优化方案,可为研判我国电力系统发展路径、制定合理转型政策提供量化参考。     

Rules for paths construction for HENs debottlenecking

This paper is based on the heat exchanger network retrofit techniques, developed by Tjoe and Linnhoff and extended by Asante and Zhu. It considers, under the Network Pinch framework, two important cases — the Retrofit Initialisation and Topology Modification when the direct application of the classic Network Pinch concept and rules is not possible. With the help of a system of simple heuristics, these limitations are overcome which extends the application range of the Network Pinch framework.     

固定床反应器催化剂装填方案的优化

脱砷反应器压降升高会严重影响压缩机的安全运行,同时也制约了装置的加工量。分析认为,压降升高的主要原因是床层空隙率减小,而空隙率减小的主要原因是床层杂质增多,堵塞了颗粒间的空隙。阐述了级配剂和除垢篮在抑制压降升高方面的作用,提出级配剂加除垢篮的组合装填方案,有效解决了固定床反应器的压降问题,使撇头周期达到9个月,并对装填方案的进一步优化提出建议。     

Energy use for subsistence and prospects for development

This paper focuses on the present use of energy in the developing countries in order to estimate the energy required for subsistence-level activities and to see how much surplus is available for economically productive activities, taking into account both commercial and non-commercial (firewood, farmwaste) sources of energy. The energy required for subsistence is estimated to be in the range of 0.3 to 0.4 tce per capita. The consumption of most low income groups countries is below this level if only commercial energy is considered. Relations are derived to explain the uses of each of these energy forms in terms of economic and demographic variables from a sample of 82 countries. These relations are then employed to show that the dependence on non-commercial energy is likely to continue beyond 2000 AD and that, inspite of the annual rise of commercial energy consumption by 6%, the improvements in per capita consumption are small because of an increase in population and a decrease in per capita non-commercial energy.     

汽轮机低压叶片材料的选择

汽轮机低压叶片的材料选择对于保证整个汽轮发电机组的安全运行至关重要。从几个方面分析讨论了汽轮机低压叶片材料选择时需要注意的问题，并提出了解决办法。     

Strategy for selection of elements for heat transfer enhancement

The present paper points out that the selection of elements for heat transfer enhancement in heat exchangers requires a methodology to make a direct comparison of the performances of heat exchanger surfaces with different elements. Methods of comparison used in the past are, in many respects, approximate and hence fail to predict accurately the relative performance of conventional heat exchanger surfaces operated with different heat exchanger elements. Owing to the direct use of the Colburn factor for performance assessment, these methods over-predict the relative performance of heat exchangers. In the present paper, a more consistent comparison method is presented and is demonstrated to work by comparison of the performance of an experimentally investigated pin fin heat exchanger with that of a smooth pipe heat exchanger. The method yields results that belong to the volume goodness factors group. It represents a practical approach, as it is applicable to all kinds of heat exchanger surfaces and does not require the conversion of the experimental data in terms of Nusselt number and friction factor for comparison purposes. The present work demonstrates that the suggested method can also be used for performance comparison of existing heat exchanger surfaces with available heat transfer and pressure loss data.     

Probabilistic design factors for pipes used for hydrogen transport

Probabilistic design factors for pipes used for hydrogen transport are proposed for 3 locations: urban, peri-urban and rural areas.The used method involves a risk equation defined as the product of probability of leakage after failure, probability to have a gas flow greater than a prescribed value, probability of ignition, probability of lethal effects greater than a threshold value and probability of the presence of a person corrected by an environment factor and a risk reduction coefficient. The results obtained are less conservative than the deterministic values provided by ASME code.