UAMA B74的目的。18-2018将提供一个国家认可的标准，用于根据涂层磨料产品（如片材、皮带、带和圆盘）上某些磨料颗粒的粒度进行分级。本标准还可作为买卖双方了解所需或供应粒度的基础。

The purpose of UAMA B74.18-2018 is to provide a nationally recognized standard for the grading by particle size of certain abrasive grain on coated abrasive products such as sheets, belts, bands and discs. The standard also serves as a basis for understanding between purchasers and sellers as to the particle size desired or supplied.