How are the accuracy grades of granite precision gauges classified?
Accuracy Grade Classification of Granite Precision Gauges (Surface Plates / Platforms)Domestically, the mainstream standard is GB/T 20428-2021 “Rock Surface Plates”, while internationally, ISO 8512-2 and DIN 876 are commonly used. The core classification is based on flatness tolerance, distinguishing grades 000, 00, 0, 1, and 2, with accuracy decreasing from high to low.I. National Standard…