扭矩加載裝置的不確定度隨被測量對象而變化，通常參考實驗數據或以長期的測量經驗來估計。通過對扭矩扳手的受力與誤差原因分析，以B類方法來評定加載裝置的標準不確定度，推導各種向量作用下引入的標準不確定度的計算公式，將實驗方法和經驗方法改變為量化方法，所得到的相對不確定度僅與扭矩扳手有效力臂長度、感測器的長度、結構表面的粗糙度、轉換接頭有關。此量化結果與PTB的實驗分析結果相吻合，該量化方法對扭矩扳手檢定儀的設計製造和使用者選擇設備具有指導意義。

The uncertainty of torque loader vary according to the measured object, usually referred the experimental data or long-term measurement experience to estimate it. Based on analyzing the forces of torque wrench and the error sources, using type B to evaluate standard uncertainty of torque loader, derived the formula of calculating the standard uncertainty under various vector action, changing the experimental methods and empirical methods into the quantification method, the relative uncertainty obtained in connection only with the effective length of force arm of torque wrench, the length of sensor, the roughness on the surface of structure and an adaptor. The quantizing results agree well with the experimental and analysis's results by PTB, it has guiding significance on design and manufacture the device for calibrating torque wrenches as well as user selects the device.