The Bond work index (BWI) is a well-known method used when selecting comminution equipment, to evaluate the grinding efficiency and to calculate the required grinding power. Although considered an industry standard, Bond did not fully define that procedure, and therefore significant discrepancies in test results can sometimes be obtained due to some undefined steps in the method. One of these cases is the initial sample size for grinding, why it must be the initial sample size of 3.35 mm, and whether it is possible to determine the BWI on samples of finer classes. In practice, it is possible to find materials whose size is finer than 3.35 mm. This paper examines the determination of the BWI on finer samples and proposes an equation for the determination of the BWI on finer samples.

粘结功指数（BWI）是在选择粉碎设备，评估研磨效率和计算所需研磨功率时使用的一种众所周知的方法。尽管被认为是行业标准，但邦德并未完全定义该程序，因此由于该方法中某些未定义的步骤，有时可能会导致测试结果出现重大差异。其中一种情况是打磨的初始样品大小，为何必须为3.35毫米的初始样品大小，以及是否有可能确定更细分类的样品的BWI。实际上，可以找到尺寸小于3.35毫米的材料。本文研究了较精细样品的BWI的测定，并提出了测定较精细样品的BWI的方程式。