500kV无人值班变电站直流电源容量配置的改造方法

直流系统是变电站的重要组成部分,其设计方案的合理性直接影响变电站的安全、可靠运行。针对500kV变电站实现无人值班新模式,对直流电源的安全性、可靠性提出更高的要求;统计分析现有有人值班的500kV变电站直流用电负荷,介绍了近年来变电站直流电源技术的发展;分析变电站内的各种直流负荷,提出满足实际需要的蓄电池容量和充电装置容量的选择方案;最后,以安徽某500kV无人值班变电站直流系统为例,计算并配置该变电站直流电源容量,为同类直流电源改造提供了参考。     

蒙乃尔K—500合金潜油电泵轴性能的研究

试验研究了为提高MonelK－500合金铸锭的成分均匀性、降低夹杂物、保证冶金质量、提高各工序的成材率，以及酸洗、热处理加工等各项关键技术，由此保证了产品的性能和生产的稳定性，使国产泵轴性能达到进口同类产品水平。     

基于Hilbert变换的相位测量法与数字相关测相法的比较

介绍了希尔伯特（Hilbert）变换测量相位差和数字相关法测量相位差的原理，进行了比较研究和试验分析，讨论了各自使用效果、优缺点及其适用的场合。结果表明，在动态检测方面，利用Hilbert变换法更能对两路同频信号的相位差进行有效的检测，是今后的研究方向。     

提高超声波探伤轧辊裂纹深度的准确度的方法

运用正交试验法，找出了超声波探伤轧辊裂纹深度最佳参数组合，提高了超声波探伤的准确度。     

Thin-skin analysis technique for interaction of arbitrary-shape inducer field with long cracks in ferromagnetic metals

In using the AC field measurement (ACFM) technique for non-destructive evaluation (NDE) of metals, a current-carrying wire structure is used to induce eddy current within a thin layer of the metal and a magnetic field sensor to measure the field perturbations in the vicinity of the metal. The sensitivity of ACFM crack detection and sizing relies on an appropriate design of the wire structure geometry together with a dully placement of the sensor. This paper presents an analytical modeling technique for evaluating the electromagnetic field interaction of an ACFM probe with a long uniform crack in a ferromagnetic metallic slab. The probe in the proposed model can have an arbitrary-shape wire inducer with no restrictions on its relative sensor position. The technique is accurate and very efficient computationally. It first uses the two-dimensional Fourier transform to obtain the field distribution at the metal surface. The Laplacian field distribution above the metal is then determined by satisfying the so-obtained boundary condition at air–metal interface. To demonstrate the accuracy of the model, we consider the special case of a rhombic wire inducer. The comparison of our results with those obtained using the conventional algorithm in the literature validates the accuracy of the model introduced in this paper. To show the generality of the model, we also present theoretical and experimental results associated with a solenoid inducer with a three-dimensional geometry for which no analytical solution is available in the literature. The theoretical prediction of crack signal supported by experimental results is used to develop a model-based method for inverting crack signal into crack depth.     

马钢冷轧轧辊缺陷的分析及防范措施

分析了马钢冷轧辊缺陷的形成机制,针对冷轧辊产生缺陷的原因,在实际生产中采取了积极有效的措施,避免带有缺陷的轧辊上机使用,大大降低了轧机的非正常停机时间,同时轧辊的吨钢消耗也大幅降低。     

Mechanical Properties of Reinforcing Steel and Fatigue Behavior in Corrosive Environment

Corrosion of reinforcing steel has a great impact on the mass reduction and high- and low-cycle fatigue. An experimental study showed that the mass loss, the fatigue limit and the life expectancy were reduced by approximately 1.50-3.00%, 20-40%, and 55-75%, respectively, according to the level of corrosion. Low-cycle strain controlled fatigue testing under ±1% and ±2.5% constant amplitude strain, indicated that the corroded steel bars exhibit gradual reduction in available energy, number of cycles to failure and the load-bearing ability. Formation of pits and notches took place on the corroded steel surface and stress concentration points were developed which are highly localized at imperfections and especially at the rib bases. The fatigue limit was reduced considerably since the existence of ribs and the formation of pits and notches combined with the mass loss led to reduction of the exterior hard layer of martensite and drastic drop in the energy density of the corroded specimens. Antiseismic design that does not take into account the maximum and cumulative plastic deformation demands and the strain history that a structure will suffer under severe ground motion could lead to unpredictable performance.     

8170缸体裂纹缺陷的探讨

对8170缸体裂纹缺陷进行了探讨分析,通过优化铸件结构,改进合金化工艺,完善浇注工艺以及随流孕育与炉前孕育工艺相结合等措施,使裂纹缺陷解决。     

腐蚀疲劳裂纹内溶液的两维运动模型

以单边穿透裂纹为背景,建立了描述腐蚀疲劳裂纹内溶液的流体运动两维方程。通过解偏微分方程组,用解析法得到了腐蚀疲劳裂纹内溶液的两维运动规律。据此,以紧凑拉伸试样为例,讨论了影响速度的各参数及裂纹内的流态。     

水电站座环及导叶用钢SXQ500/550DZ35热力学计算及析出相分析

水电建设的发展，对水电站座环及导叶用SXQ500/550DZ35特厚板的性能提出了更高的要求，其成分中加入合金元素多，各种相的析出复杂，而析出相与钢的组织性能密切相关，因此利用Thermo Calc软件对SXQ500/550DZ35水电用钢进行了热力学计算及平衡相分析。结果表明，FCC_A1#2、FCC_A1#3及FCC_A1#4相析出温度区间集中于900~1 400 ℃之间，属于微合金元素V、Nb、Ti与C、N元素结合生成的碳化物以及碳氮化物，其能钉扎奥氏体晶界，细化奥氏体晶粒。通过钢板在970、1 020、1 070 ℃保温22 min后水淬至常温，并采用场发射电镜对其进行检测，析出相主要为NbC、TiC、Ti（C,N），与热力学软件计算相符合。