制样设备的精密度测定和偏倚试验

Precision Measuring and Bias Test for Sample Preparation Equipment

因燃煤质量检验中具有代表性样品的检验误差主要来源于制样,制样设备偏倚的大小以及精密度上下限的范围决定了样品的准确性。根据GB474—2008《煤样的制备方法》的规定:对制样精密度产生怀疑时或新的缩分机和制样机投入使用时,应对制样设备进行精密度核验和偏倚试验,为此,依据GB/T19494.3—2004《煤炭机械化采样第3部分:精密度测定和偏倚试验》对长时间未使用的1台制样机和新购置的1台电动缩分机进行了偏倚试验和精密度核验,对试验结果进行了详细的分析并给出相应的结论。

For reason of that the inspection error of typical sample in fire coal quality inspection comes from sample prepara- tion of which the size of bias and upper and lower bound of precision decide correction of the sample. According to provision of GB 474-2008 preparation method for coal sample which states that it is ought to proceed precision examination and bias test for sample preparation equipment when suspecting precision of sample preparation or inputting new shrinkage extension and sampling machine. Therefore, according to provisions of GB/T 19494.3-2004 coal mechanization sampling, the third part ： precision measuring and bias test, this paper introduces bias test and precision examination for one sampling machine and a new bought motor-driven shrinkage extension that are not used for a long time. It analyzes the testing results and draws a relevant conclusion.