钻井泵活塞寿命可靠性研究

采用数理统计方法对大庆油田常用的三种钻井泵活塞的寿命分布规律作了研究，应用可靠性理论计算和分析了活塞可靠性指标。同时，为比较和综合评价三种活塞的质量，对活塞寿命方差和均值的差异性作了检验。为探求活塞寿命与各影响因素之间的关系，对清水介质条件下新旧两种标准活塞强化试验数据进行了多项式拟合和分析。研究表明，三种活塞的使用寿命均服从二参数威布尔分布，活塞的失效类型属耗损型。因此，延长活塞寿命的关键是延长活塞的正常磨损阶段。必须从改进设计，提高制造水平和改善使用条件等方面综合提高活塞的耐磨性。

Life and reliability of drill pump pistons

The distribution Pattem of life of three kinds of drill pump pistons used conunonly in Daqing Oiffield is investigatedby the mathematical statistics methed. The reliability index of the piston is ealculated and analyzed by using the reliabilitythoory. The differences of the variances and mean values of the piston life are checked to compare and evaluate the qUali-ty of the three kinds of piston. To investigate the relationship between the piston life and lelevant affecting factors, poly-nowial fitting and analysis of the data obtained dri the strengthening test of old and new standaId pistons are made. Theresult of investigation shows tLhat the service life of the three kinds of pist0ns is sub0Idinate to Weibull distribution, andthe piston failure is ndnly caused by weai. Therefore the wear lesistance of the piston should be improved to extend itsservice life.