Jour : 05/22/2026

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…

I. Conventional Service Life (Industry Actual Tests National Standard Experience)000/00 Grade Ultra-Precision Grade (CMM bases, metrology room standard parts)Constant temperature and humidity metrology room, no impact, standardized use: 20–40 years. Flatness and perpendicularity accuracy decay extremely slowly; regular re-measurement and fine-tuning allow for long-term use.0 Grade Precision Grade (Laboratories, precision machining workshops)Dry workshop, light-load use,…