组织号
Structure number

组织号是指磨粒体积占磨具体积的百分率。磨粒所占的比例越大，组织就越紧密；反之就疏松。组织疏松（磨粒率低）的磨具，磨粒间的气孔多，排屑方便，工件散热性好，不烧伤。组织紧密（磨粒率高）的磨具，能保持较好的几何，被磨工件的表面粗糙度好，加工精度高。

Structure number is the percentage of the grain volume in the volume of abrasive tools. The bigger the grains’ percentage is, the denser the structure is. Otherwise, the structure is porous. The abrasive tools in the porous structure are characterized by more holes among grains and easily-removing metal fillings, and excellent capacity of heat-radiating and burning no workpieces. The abrasive tools in dense structure feature well-kept shapes and high cleanness of the workpieces and high grinding precision.