关键词: 支撑剂, 破碎率, 浊度, 准确度, 不确定度, 标准差, 重复性, 再现性

Abstract: Proppant is a key material to ensure the effect of hydraulic fracturing job and oil well production. Its quality is under the strict control of SY/T 5108-2014，an petroleum industrial standard of proppant testing. But this standard does not cover the final measurement of uncertainty. Uncertainty is of significant importance for the quality control of testing laboratories，the differences between laboratories and the differences in product characteristics. Therefore，the samples of four kinds of proppant were sent to more than 60 laboratories，and the test data obtained were used to calculate the standard deviation and uncertainty in standard repeatability and reproducibility. The results show that acid solubility and turbidity in SY/T 5108-2014 are highly uncertain，and the uncertainty increases with the increase in measured values. When the measured solubility is 7% of the critical value，and the measured turbidity is 150 FTU，the uncertainty can reach 1.5% and 13 FTU，respectively. The maximum uncertainty in crushing percentage is about 2.2%，and the uncertainty in roundness and sphericity is 0.1. The uncertainty decreases with the increase in measured values. The error of absolute density comes from systematic differences in the equipment of different manufacturers. This study provides technical support for revising the evaluation standard of proppant performance，as well as engineering and technical staff to correctly understand and apply the test results of proppant performance.

Key words: proppant, crushing percentage, turbidity, accuracy, uncertainty, standard deviation, repeatability, reproducibility