天平校准不确定度的一种评估方法

摘要

建立了一套完整的天平校准不确定度评估流程：单独评估校准系统的不确定度、基于检验载荷的残差，通过偏差极限和精度极限评估其它各误差源引入的不确定度、合并得到校准不确定度结果。以BCS-100天平校准系统为例，选择天平TG624C重复校准7次，实现了该评估方法。评估结果表明：（1）天平安装的滚转角和加载时天平的角位移，二者引入的不确定度为主要分量，应作为技术改造的重点；（2）Q、Z和My 3个小量单元，受Y和Mz 2个大量的干扰，其不确定度值稍大；（3）精度极限相比于偏差极限要小很多。建立的整套评估方法对于其他校准系统也是通用的。%A complete uncertainty estimation process for balance calibration is established:as-sessing the calibration system uncertainty,assessing the bias limit and precision limit based on checking load residuals to estimate the uncertainty from other errors,and combining them to ob-tain the total uncertainty result.For the BCS-100 calibration system,balance TG624C is calibra-ted seven times repeatedly to implement the method.The result shows that:(1 )The uncertainty caused by the roll angle of balance installation and the angular displacement of balance in the cali-bration are the main components,which shows the direction to upgrade the calibration system;(2)Due to the interference ofY and Mz,the uncertainties of Q、Z and My are larger;(3)The pre-cision limit is much smaller compared to the bias limit.The method is also applicable to other calibration systems.