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81.
文章介绍了现阶段修船企业在设计管理方面的流程和经验,总结并提出设计在船舶修理中具有重要的地位及发展趋势。就修船企业而言,如何充分利用工厂自身条件,合理设计出切实可行、节约成本、为公司提高经济效益的船舶修理产品,有特别的实际意义。 相似文献
82.
重载货车车轮踏面垂直磨耗原因分析及改进 总被引:2,自引:0,他引:2
分析总结了大秦线重载货车车轮磨耗的原因,并针对解决大秦线车轮非正常磨耗提出几点建议。 相似文献
83.
合理利用城市桥下空间,对于充分利用道路空间资源、节省城市土地资源具有重要现实意义,也越来越引起人们的关注。近年来,各地区因为违规占用桥下空间引起的火灾越来越频繁。现结合实际工程,浅谈城市桥梁火灾后如何在保证交通不中断的情况下快速修复受损结构。 相似文献
84.
85.
介绍CAT 824G轮式推土机空调冷气装置孔管系统结构,空调控制电路原理及维修经验. 相似文献
86.
重载铁路轮轨磨损原因探讨 总被引:2,自引:0,他引:2
根据轮轨接触理论,分析了不同轮轨接触几何匹配关系下的轮轨接触应力情况,指出轮轨接触应力、轮轨接触几何关系、轴重是影响重载铁路轮轨磨损的主要因素,从重载运输装备方面提出了减少轮轨磨损的几点建议。 相似文献
87.
针对矿用汽车后桥壳体修复工艺中存在的焊接材料和焊机不易选择、焊件表面较难清理干净、坡口形式与裂缝尺寸不匹配、焊接工艺处理不当等疑难问题,提出了选用低氢钠型碱性焊条及直流逆变焊机等解决方案。经用户使用检验,修复后的车辆连续运行30000km以上均未出现异常,节约了维修成本。 相似文献
88.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(1):109-131
It is well known that track defects cause profound effects to the dynamics of railway wagons; normally such problems are examined for cases of wagons running at a constant speed. Brake/traction torques affect the speed profile due to the wheel–rail contact characteristics but most of the wagon–track interaction models do not explicitly consider them in simulation. The authors have recently published a model for the dynamics of wagons subject to braking/traction torques on a perfect track by explicitly considering the pitch degree of freedom for wheelsets. The model is extended for cases of lateral and vertical track geometry defects and worn railhead and wheel profiles. This paper presents the results of the analyses carried out using the model extended to the dynamics of wagons containing less ideal wheel profiles running on tracks with geometry defects and worn rails. 相似文献
89.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(6):711-733
The traction control system (TCS) might prevent excessive skid of the driving wheels so as to enhance the driving performance and direction stability of the vehicle. But if driven on an uneven low-friction road, the vehicle body often vibrates severely due to the drastic fluctuations of driving wheels, and then the vehicle comfort might be reduced greatly. The vibrations could be hardly removed with traditional drive-slip control logic of the TCS. In this paper, a novel fuzzy logic controller has been brought forward, in which the vibration signals of the driving wheels are adopted as new controlled variables, and then the engine torque and the active brake pressure might be coordinately re-adjusted besides the basic logic of a traditional TCS. In the proposed controller, an adjustable engine torque and pressure compensation loop are adopted to constrain the drastic vehicle vibration. Thus, the wheel driving slips and the vibration degrees might be adjusted synchronously and effectively. The simulation results and the real vehicle tests validated that the proposed algorithm is effective and adaptable for a complicated uneven low-friction road. 相似文献
90.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(2):235-261
Excitation force spectra are necessary for a realistic prediction of railway-induced ground vibration. The excitation forces cause the ground vibration and they are themselves a result of irregularities passed by the train. The methods of the related analyses – the wavenumber integration for the wave propagation in homogeneous or layered soils, the combined finite-element boundary-element method for the vehicle–track–soil interaction – have already been presented and are the base for the advanced topic of this contribution. This contribution determines excitation force spectra of railway traffic by two completely different methods. The forward analysis starts with vehicle, track and soil irregularities, which are taken from literature and axle-box measurements, calculates the vehicle–track interaction and gets theoretical force spectra as the result. The second method is a backward analysis from the measured ground vibration of railway traffic. A calculated or measured transfer function of the soil is used to determine the excitation force spectrum of the train. A number of measurements of different soils and different trains with different speeds are analysed in that way. Forward and backward analysis yield the same approximate force spectra with values around 1 kN for each axle and third of octave. 相似文献