Calculation of seismic transmission speed of HTI medium

During the seismic wave propagation process,as for the anisotropic lower medium,the speed is a function of the propagating direction.This article focuses on solving the problem how to get the transmittance angle and speed,knowing the upper seismic wave propagation velocity and the angle of incidence conditions.The main theories used Snell law,Christoffel equation and speed characteristics.Taking the HTI medium as an example,the authors give the detailed solving process and draw the space velocity characteristic curve.

核电站两位三通交流电磁阀共性问题分析及改进

秦山核电一期350MW机组常规岛两位三通电磁阀近5年缺陷频发,失效表现多为开关不严、漏气,甚至无法跳动且伴随巨大噪音。为减少该类型电磁阀在秦山基地的共性缺陷,对同类型交流电磁阀问题解决提供新的辅助思路。通过电磁阀外观检查、显微观察、线圈直阻、电压、泄漏测试、密封性等材料及性能试验,找到同型号不同寿命周期的交流电磁阀共性缺陷原因,并结合秦山一期电磁阀使用环境情况、预防性维修频度、历史缺陷情况,对电磁阀问题进行深入分析研究。研究结果表明,秦山一期电磁阀线圈性能下降,电磁阀弹簧变形导致电磁阀有效吸合时间减少为事件根本原因。通过增加验收手段,维修规程中增加直阻测量阻值,对长带电电磁阀增加使用检漏液进行检漏的要求等优化改进措施,可及时降低电磁阀故障频率。