大型发电机定子槽楔松动的声检测研究

针对使用波纹的大型发电机定子槽部固定结构，在实验室建立了槽楔松动模型。利用自行开发研制的声检测系统对该槽楔松动模型进行声检测研究。研究表明在波纹板的弹性范围内，随着波纹板形变量的加大，测得的声信号能量谱图中主频率值逐渐增加。该主频率值可用来定量计算波纹板的形变量，并作为判断槽楔松动程度的特征参量。     

Theoretical method for estimation of mean pressure on contact area between rolling tools and workpiece in cross wedge rolling processes

The paper gives a new method no determine the mean unit contact pressures on a material—tool contact surface in cross wedge rolling processes (CWR). The dependencies worked out on the basis of the energy and the upper bound methods permits rolling forces to be determined which are comparable to experimentally measured ones. The analysis provides equations which relate the mean contact pressure q_m to the basic process parameters, namely the forming angle α, the spreading angle β, the relative reduction of a portion δ and the shear friction factors m and m_k.     

Forward and Backward Slip Models in MAS Rolling Process and Its OnLine Application

Based on the MAS rolling process in plate mill, the mathematical models of forward and backward slips of the wedges at plate head and tail were derived. According to the new model, the difference between the forward slip of the wedge and that of the normal part of the plate is obviously very small. The deviation is less than 25% in general. Thus, in actual application, the forward slip of normal part of the plate can be used to calculate the length of rolled plate instead of the derived model. The rationality of this simplified method was confirmed with the application in Shougang 3 500 mm plate mill. The test results showed that the wedges of plate head and tail are symmetrical. The plate width deviation is greatly decreased by using the MAS method.     

楔横轧梯形螺纹轴模具关键参数的研究

楔横轧螺纹轴的金属流动规律和模具齿高等参数的确定对于模具设计意义重大.以轧制过程金属体积不变原理为前提,运用数学积分法求得模具齿顶高初值和轧件初始直径,进而设计模具孔型.对于设计的模具,采用DEFORM-3D有限元软件模拟轧制成形过程,得到较理想的梯形螺纹轴.该模拟结果验证了由齿顶高参数设计模具孔型进行楔横轧梯形螺纹轴轧制的可行性,为课题的深入研究提供了理论依据和参考价值.     

中心楔块精锻工艺及数值模拟

在分析中心楔块锻造工艺的基础上,结合成形过程的数值模拟,优化精锻模具和工艺参数,解决了锻件表面质量和尺寸精度要求高的难点,成功开发出中心楔块精锻成形生产工艺.     

气隙取气转子风斗取风性能的相互影响实验研究

气隙取气斜流通风系统是大型汽轮发电机中应用较广的一种通风方式。为了研究不同结构转子进、出风斗的取风能力和引风能力,对气隙取气通风系统进行了静态实验模拟研究,得到了进风斗和出风斗取风性能之间相互影响规律,为转子气隙取气通风系统的优化设计提供一定的参考。     

发电机端部线圈及汽轮机汽封的质量事故及其防范

结合两例发电机线圈故障,指出了新设备的薄弱环节和新机组投入运行后的维护要点,提出对发电机运行振动模态试验的重要性,防范发电机组端部线圈质量事故的发生。     

楔形光纤探针传输效率的研究

用实验方法测量了楔形光纤探针的传输效率随光纤楔角的变化关系,作出传输效率曲线,通过测定楔形光纤探针传输效率的实验可知,楔体角度越大,过渡区越短,泄漏光就越少,传输效率会提高.在楔角由20.2° 增大到33.6°以及楔角由55.8°增大到83.6°时,传输效率曲线呈较快的上升趋势;在楔角由33.6° 增大到55.8°,传输效率曲线上升趋势较缓.在相同的条件下,楔形光纤探针的传输效率随入射光波长的增大而快速地下降.     

行李箱外板斜楔翻边模设计

对某车型行李箱外板上部斜楔翻边模的工序内容和结构难点进行了分析,介绍了斜楔翻边模搓板驱动滑块结构和翻边随动压料结构的原理及作用,为今后的斜楔翻边模特殊结构设计提供新的思路.     

冷轧机组斜楔调整装置的应用及故障分析

介绍了冷轧机组斜楔调整装置在应用中出现的故障，通过实践提出了故障排除方法，对于采用斜楔装置作调整执行机构的机械设备有较大的借鉴意义。