Jour : 06/16/2026

I. Executive StandardsManufacturing Standard: JB/T 10027-2017 “Granite Surface Plates, Straight Edges, Squares, and Square Boxes”Verification Standard: JJG 117-2013 “Verification Regulation for Surface Plates”Accuracy Grade: Grade 000, Grade 00, Grade 0 (the smaller the number, the higher the accuracy); some scenarios still use the old standard Grade 1 (General Industrial Grade). II. Grade Definitions and ApplicationsGrade…

Granite Precision Square Block: Application Scenarios and DescriptionGranite square blocks (also known as granite right-angle square blocks or inspection square blocks) are manufactured according to JB/T 10027-2017. Featuring multiple faces mutually at 90°, high flatness/perpendicularity, and strong stability, they are classic three-dimensional reference gauges in the machinery industry, widely used for scribing, inspection, clamping, and…