Height Gauge
SPT Metrology supplies high-precision Height Gauges designed for accurate vertical measurement, layout marking, and...
Granite Square
Precision Master Square for X-Y-Z Axis Inspection & High-Accuracy Alignment
Product Overview
As a trusted Granite Square Manufacturer, SPT Metrology manufactures high-precision Granite Squares engineered to serve as master references for inspecting the X, Y, and Z axes of machine tools, CMMs, and precision assemblies. These granite master squares are essential tools in metrology labs, tool rooms, machine shops, and calibration facilities where ultra-high squareness and parallelism accuracy are required. Manufactured from premium-grade, naturally seasoned black granite, our master squares deliver exceptional dimensional stability, rigidity, and long-term accuracy—far superior to traditional cast iron or steel squares.
Each granite square is finished to Grade-0 accuracy, ensuring that opposite faces are perfectly parallel and adjacent faces are precisely perpendicular to each other. All reference faces are finely lapped using advanced processes that deliver unmatched flatness and straightness. This makes the granite square an ideal standard for checking spindle alignment, machine column orthogonality, guideway squareness, fixture alignment, and geometric calibration of CNC machinery.
Granite’s natural properties—low thermal expansion, non-magnetic structure, resistance to corrosion, and superior vibration damping—make it the preferred material for high-precision inspection. Unlike metal squares, granite does not warp, rust, or develop burrs, ensuring highly repeatable results even under continuous workshop use. The rigid block design provides excellent stability, allowing reliable measurements without deflection.
SPT Metrology granite squares are widely used for:
- Verifying squareness of machine tool axes (X, Y, Z)
- Calibrating CMM and CNC machining centers
- Inspecting perpendicularity of jigs, fixtures, and assemblies
- Checking straightness and alignment of mechanical structures
- Setting up high-precision tooling and machine bases
To support safe handling, our granite squares are provided with precision-machined lifting holes, allowing secure movement without affecting accuracy. Available in multiple sizes and configurations, they can also be customized to suit specific industrial applications.
Choose SPT Metrology Granite Squares for dependable accuracy, long-lasting stability, and world-class performance—precision-engineered to meet the demanding requirements of modern manufacturing and inspection systems.
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