基础振动下直动式溢流阀的阀口泄漏分析

Analysis of valve port leakage on direct operated relief valve under foundation vibration

针对硬岩掘进机(TBM)在掘进过程中产生的振动影响液压元件内泄漏的问题,分析基础振动及结构参数对溢流阀阀口泄漏量的影响规律.以安装在TBM基础上的直动式溢流阀为研究对象,建立基础振动下溢流阀的阀口泄漏量数学模型.通过计算基础振动引起的溢流阀阀口泄漏量,确定溢流阀发生阀口泄漏时的临界入口压力.结果表明:阀口泄漏量随着基础振动振幅及频率的增大而近似线性增大;当弹簧刚度小于1.3×105 N/m时,阀口泄漏量随着弹簧刚度的增大而增大;当弹簧刚度为1.3×105 N/m时,阀口泄漏量达到最大值;减小弹簧刚度和阀芯质量可以显著减少因基础振动引起的阀口泄漏故障,从而提高溢流阀的工作稳定性.

Aiming at the problem that vibration caused by tunnel boring machine （TBM） during the process of tunneling has effect on leakage in hydraulic components, the relief valve leakage rate caused by foundation vibration and structure parameters was analyzed. Taking the direct operated relief valve installed on TBM as the example, a mathematical model of valve port leakage of relief valve under foundation vibration was established. Critical inlet pressure was determined by calculating the leakage caused by foundation vibrations. Results showed that the amount of valve port leakage increased approximately linearly as the amplitude and frequency of vibration increased. When the spring stiffness was smaller than 1.3 ×10^5 N/m, the valve leakage increased as the spring stiffness increased; while when the spring stifness equaled to 1.3 × 10^5 N/m, the valve leakage reached the maximum. Reducing spring stiffness and spool mass can decrease the valve port leakage fault caused by foundation vibration significantly, and improve the working stability of relief valve.