同轴度对千斤顶测得值的影响分析

Influence of Coaxiality on Measurement Results of Jack

为探究同轴度对千斤顶测得值的影响,采用重锤法测量千斤顶轴线与标准测力仪主轴线间的同轴度。根据测得值计算了不同同轴度下千斤顶力值绝对误差、相对误差和内插误差间差。实验结果表明,千斤顶力值绝对误差和相对误差都随着同轴度的增大而增大;当同轴度一定时,力值绝对误差随着压力值增大而增大,压力值越大,增大效果越明显。但是,力值相对误差并没有随着压力值的增大而增大,而是在±0.5%区间范围内变化,同轴度对千斤顶测量力值的影响量不大于0.5%,在扩展不确定度评定时应当引入同轴度对千斤顶测量力值的不确定度这一分量。此外,内插误差间差并未随着同轴度的增大而增大,而是在±0.1%区间范围内变化,同轴度对千斤顶内插误差的影响量不大于0.1%。

To explore the Influence of coaxiality on measurement results of jack,Coaxiality between the axis of the jack and the main axis of the standard dynamometers was measured by Heavy hammer method. TheJack force value absolute error,relative error and inter - interpolation error which were calculated at different coaxialities according to the measurement results . The experimental results show that the absolute and relative errors of the jack force value increased with the increase of the coaxiality. When the coaxiality is constant,the force absolute error increased as the pressure value increases. The larger the pressure value,the more obvious the increase effect. However,the force relative error does not increase with the increase of the pressure value,but varies within the range of ±0. 5%. The influence of the coaxiality on the measured force value of the jack is not more than 0. 5%. In the evaluation of the extended uncertainty,the component of the coaxiality to the uncertainty of measurement force value of the jack should be introduced. In addition,the inter - interpolation error does not increase with the increase of the coaxiality, but varies within the range of ± 0. 1%,and the influence of the coaxiality on the jack interpolation error was not more than 0. 1%.