Granite Precision Square Block: Application Scenarios and Description
Granite 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 calibration.
I. Core Advantages (Compared to Metal Square Blocks)
No deformation, low internal stress, and stable accuracy over long-term use;
Low coefficient of linear expansion, minimal temperature variation effects, suitable for precision inspection;
Rust-proof, non-magnetic, wear-resistant, and vibration-absorbing, unlikely to scratch workpieces;
Six faces / adjacent faces are strictly perpendicular, allowing multi-face switching as a reference.
II. Main Application Scenarios
- Precision Inspection and Geometric Tolerance Verification
Using the vertical face of the square block as a reference to inspect the perpendicularity, parallelism, coaxiality, and end-face runout of workpieces;
Paired with dial indicators, dial test indicators, height gauges, and lever gauges to inspect shafts, boxes, flanges, precision castings / machined parts;
Comparative inspection of right-angle errors on various vertical and stepped surfaces of parts, replacing traditional metal square blocks for high-precision workstations. - Equipment and Gauge Calibration
Calibrating conventional gauges such as right-angle rulers, straight edges, square rulers, gauge stands, and dial indicators;
Installation and commissioning of machine tools, coordinate measuring machines (CMMs), and vision measuring machines, verifying the perpendicular reference of worktables, columns, and guide rails;
Serving as a three-dimensional 90° reference in metrology rooms to complete value comparisons and daily calibrations. - Precision Scribing and Process Prototyping
Three-dimensional scribing in machining and mold industries: workpieces are adsorbed / pressed against the vertical face of the square block to scribe perpendicular lines, contour lines, and position lines;
Multi-directional flip scribing, utilizing the six-face perpendicularity feature to complete scribing for multiple positions in a single clamping, improving efficiency. - Tooling Clamping and Auxiliary Positioning
Temporary positioning of workpieces at workshop and quality inspection stations, serving as a fixed right-angle reference;
Used in conjunction with suction cups and fixtures for perpendicular positioning and inspection of small precision parts, electrodes, and mold inserts;
Assisting in aligning workpieces on grinders, milling machines, and machining centers, correcting the right-angle posture of workpieces. - Laboratory / Quality Inspection Room Special Use
Serving as a standard three-dimensional reference in constant-temperature metrology rooms and third-party testing agencies;
Used in conjunction with optical instruments and precision inspection platforms to ensure a unified measurement reference.
III. Accuracy Grades and Corresponding Selection
Similar to granite square rulers, they are divided into Grade 000, Grade 00, and Grade 0
Grade 000: Metrology rooms, standard traceability, high-precision instrument calibration;
Grade 00: Precision quality inspection, CMM commissioning, mold / aerospace part inspection;
Grade 0: On-site inspection in production workshops, scribing, auxiliary alignment for ordinary machine tools.
IV. Usage Precautions
Handle with care, strictly forbid impact or dropping to avoid chipping or scratching the working surface;
Keep the working surface clean, forbid stacking heavy objects or hammering workpieces;
Avoid contact with strong acids and alkalis, store in a dry, room-temperature environment;
Send for regular inspection and calibration to ensure the validity of the reference accuracy.
