电阻式混凝土磨蚀传感器及其测量方法

结合一项国家实用新型专利介绍电阻式混凝土磨蚀传感器的工作原理,以及基于2芯线、3芯线和5芯线的电阻式混凝土磨蚀传感器的设计方案和测试方法。以E-24系列精度为5%的碳膜电阻为例,规定了传感器各个固定电阻的阻值,分析了电阻阻值误差和电阻变化量对磨蚀深度分级判断的影响,并用基于2芯线设计方案的传感器进行室内测试试验,结果表明电阻式混凝土磨蚀传感器适用于泄水建筑物混凝土表面的磨损和空蚀测量,可以用于实时监控建筑物的运行状态。     

非定常固液两相流对双流道泵磨损性能的影响

基于Mixture多相流模型和RNG k-ε湍流模型,应用Fluent软件对双流道泵内非定常固液两相流进行了数值模拟,并分析了两相流对双流道泵磨损性能的影响。结果表明：泵的扬程和效率均随时间变化呈现正弦性规律;固相颗粒主要集中在叶轮前、后盖板和蜗壳进口前壁面处;叶轮后盖板中间凸起部位发生严重冲击磨损,其他区域均发生滑动磨损;蜗壳壁面均发生滑动磨损,而隔舌部位发生较为严重的冲击磨损。研究结果可为双流道泵的性能预测和优化提供一定的理论支撑。     

水流含沙量和流速对水轮机磨蚀性能的影响

水流含沙量和流速是影响水轮机磨蚀性能的非常重要的两大因素,其影响规律对水轮机磨蚀的防治有很重要的理论意义和参考价值.采用黄河原型沙,通过试验研究不同泥沙含量和不同水流流速条件下水轮机材料的磨蚀外貌、磨蚀失重量和磨蚀失重率.通过对试验结果进行定性和定量分析,得到水轮机磨蚀与水流含沙量、磨蚀与水流流速之间的关系,并得到数学回归式,找出水轮机磨蚀的基本规律,为多泥沙河流水轮机的参数选择与磨蚀防治提供了依据.     

Evaluation of surface textures and skid resistance of pervious concrete pavement

Surface textures had long been recognized as primary factors to provide the skid resistance on pavements; however, no measurement of skid resistance on pervious concrete pavement with various surface texture parameters had been made. Fractal geometry was introduced in the present work to accurately simulate transect contour curves of pervious concrete specimens through fractal interpolation. It is proved that its fractal dimension (D) can be adopted to measure the skid resistance on pervious concrete pavement, overcoming the shortcomings of both macrotexture depth (DT ) and British portable pendulum number (NBP). Combined with Fujikawa-Koike tire/road contact model, the optimization method of all surface textures was recommended for designing and constructing excellently skid-resistant and noise-absorptive pervious concrete pavement. In addition, evaluating of the abrasion process and attenuation of the surface textures on concrete pavement slabs was also the focus of this work based on accelerated abrasion test. Results show that the surface textures on pervious concrete pavement slabs is extremely durable, compared to those on conventional grooved or exposed aggregate concrete pavement slabs.     

Characteristics of electrocodeposited Ni-Co-SiC composite coating

Electrodeposited composites are gaining importance for their advantages including low cost, ease and simplicity of operation to tailor made coatings for tribological applications. Generally, composites containing carbides (like SiC) are preferred for high wear resistance along with increased hardness, improved corrosion resistance, and high temperature oxidation resistance as compared to alloy and pure metal electroplating. In the present work, electrolytic codeposition technique was adopted in the deposition of Ni-Co-SiC composite coating on mild steel substrate, using nickel alloyed with cobalt as the binder phase with SiC as dispersed particles. To improve the properties of coating further, Cr plating was also performed. Since the particle size and volume percent variation of dispersoid have great importance in codeposition, so the effect of these two variables on the process of codeposition and properties was observed. Morphological studies of Ni-Co-SiC coating were carried out with scanning electron microscopy and X-ray diffraction analysis to correlate the mechanical and corrosion behaviour of the coating.     

电力牵引用内包式钢铝接触线磨耗计算

介绍了内包式钢铝接触线的结构及其尺寸,以及磨耗高度与磨耗面积对应的关系,即磨耗换算表,以有利于接触线的安全运行,能及时补强或更新。     

Microstructure and abrasion wear behavior of Ni-based laser cladding alloy layer at high temperature

Ni-based alloy coating on 21-4-N heat-resistant steel was prepared using CO2 laser, and the high-temperature abrasion wear was tested. The microstructure of this cladding layer and its abrasion wear behavior at high temperature by changing compositions and temperatures were investigated by means of optical microscope and scanning electron microscope. Among the three compositions of cladding layer, i.e. Ni21 ＋20% WC＋0. 5 % CeO2, Ni25＋20 % WC＋0. 5 % CeO2 and Ni60 ＋ 20 % WC ＋ 0. 5 % CeO2, the experimental results show that Ni21 ＋ 20 % WC ＋ 0.5?O2 cladding layer is made up of finer grains, and presents the best abrasion wear behavior at high temperature. The wear pattern of laser cladding layer is mainly grain abrasion at lower temperature, and it would be changed to adhesive abrasion and oxide abrasion at higher temperature.     

模拟空间状态下的粉末冶金摩擦材料性能

研究了用粉末冶金方法生产的非金属含量较高的摩擦材料在模拟空间状态下的摩擦磨损性能。重点探讨了材料中非金属组元(特别是摩擦组元、润滑组元)对材料的摩擦性能及稳定度的影响。结果表明在模拟空间状态下, 无论是铁基还是铜基, 或是Fe/Cu基的摩擦材料仍然遵循在大气状态下的规律。研究结果表明除宇宙射线粒子的影响未考虑外, 模拟空间状态下摩擦性能最稳定的是具有一定润滑性能, 且非金属成分的体积分数比较高的铜基粉末冶金摩擦材料。     

炭黑与橡胶模量及磨耗的相关性研究

依据炭黑可以影响硫化橡胶模量和磨耗的事实，通过制备几种不同炭黑含量的硫化橡胶。对高结构、高耐磨的N339炭黑填充的硫化橡胶模量及各种条件下的磨耗进行测定，分析炭黑用量与模量、磨耗相互之间的关系．     

前苏制锅炉甲侧排粉机叶轮磨损严重的问题分析及措施

分析了前苏制670t/h锅炉甲侧排粉机的出口风管阻力小于乙侧排粉机的风管阻力,造成甲侧制粉系统的通风量大于乙侧排粉机的通风量,致使甲侧排粉机的叶轮磨损严重,提出按工况实测数据作依据,调节甲侧排粉机入口风门,降低通风量,达到减轻磨损的目的。