Jour : 06/15/2026

Granite Precision Square Accuracy Grade Classification Domestic Executive Standard: JB/T 10027-2017 “Granite Surface Plates, Straight Edges, and Squares”, classified by working surface flatness, squareness accuracy, and parallelism, divided into three grades: 000, 00, and 0. The smaller the grade number, the higher the accuracy. I. Grade Positioning (Application Scenarios)Grade 000 (Reference Grade)Highest accuracy, limited to…

Granite precision square is a high-precision geometric measurement standard, primarily used for the inspection and calibration of perpendicularity, parallelism, and flatness, and is widely applied in fields such as machinery manufacturing, precision assembly, metrology calibration, and aerospace. I. Core Features (Why Granite)High Stability: Natural aging and internal stress release ensure long-term deformation-free performance; low coefficient…