YANRUN Precision Polygon Prism (8-, 12-, 17-, 23-, 24-, 36-, and 72-Faced), Grade 1
| Brand | YANRUN |
|---|---|
| Origin | Shanghai, China |
| Manufacturer Type | Direct Manufacturer |
| Product Category | Domestic |
| Model | Grade 1 Metal Polygon Prism |
| Component Type | Calibration Standard |
| Face Count Options | 8, 12, 17, 23, 24, 36, 72 |
| Outer Circumscribed Diameter | φ80 mm (8-face), φ100 mm (12-/17-face), φ120 mm (24-face), φ150 mm (36-face) |
| Thickness | 17 mm |
| Central Bore Diameter | φ25 mm |
| Material | GCr15 bearing steel |
| Hardness | HRC 62–65 |
| Working Surface Flatness (Grade 1) | ≤0.05 µm |
| Perpendicularity of Working Faces to Reference Base (Grade 1) | ≤10 arcseconds |
| Surface Roughness (Ra) | ≤0.025 µm |
| Parallelism of Top Surface to Reference Base | ≤2 µm |
| Working Angle Deviation (Grade 1) | ±2 arcseconds |
| Working Angle Measurement Uncertainty (Grade 1) | 0.5 arcseconds |
| Effective Working Area | ≥φ15 mm circular zone |
Overview
The YANRUN Precision Polygon Prism is a primary angular calibration standard engineered for metrological traceability in high-accuracy angular measurement systems. Based on the principle of multi-faceted symmetry and autocollimation-based angle subdivision, this polygon prism serves as a physical realization of discrete angular intervals—each face defining a precisely known working angle relative to a common reference axis. Unlike rotary encoders or electronic angle sensors, the polygon operates without electronics or moving parts, delivering intrinsic stability and long-term repeatability essential for laboratory-grade calibration. Its design conforms to the foundational metrological requirements outlined in ISO 230-7 (Test Code for Machine Tools – Part 7: Angular Measurements), and supports verification protocols for optical dividing heads, precision rotary tables, autocollimators, theodolites, and angle encoders used in aerospace component inspection, coordinate measuring machine (CMM) angular axis validation, and ultra-precision gear hobbing setups.
Key Features
- Manufactured from vacuum-melted GCr15 high-carbon chromium bearing steel, heat-treated to HRC 62–65 for dimensional stability and wear resistance under repeated contact loading during autocollimator alignment.
- Grade 1 geometric certification per JJG 102–2021 (Chinese National Verification Regulation for Polygons) and aligned with international best practices for polygon standards—verified via interferometric flatness mapping and multi-axis autocollimator comparison.
- Face count selection (8, 12, 17, 23, 24, 36, 72) enables optimized error separation: even-faced polygons (e.g., 24- or 36-face) isolate large-period errors (e.g., bearing wobble, axis eccentricity); odd-faced variants (17- or 23-face) enable simultaneous evaluation of both large- and small-period errors (e.g., encoder subdivision nonlinearity), supporting comprehensive uncertainty budgeting per ISO/IEC 17025.
- Central φ25 mm bore allows rigid mounting on precision spindles or air-bearing rotation stages with minimal runout; outer diameters scaled to face count ensure mechanical rigidity and thermal homogeneity (φ80 mm to φ150 mm).
- Working surface flatness ≤0.05 µm and surface roughness Ra ≤0.025 µm minimize diffraction-induced beam deviation during autocollimation, ensuring consistent retroreflection across all faces.
Sample Compatibility & Compliance
This polygon prism is compatible with all industry-standard optical angular measurement instruments utilizing collimated light and autocollimation techniques—including Zeiss, Mitutoyo, and Keyence autocollimators; Renishaw XL-80 and API Radian laser interferometers (in angular mode); and custom-built null-compensation setups. It satisfies mechanical interface requirements for ISO 10791-7 (Test conditions for machining centres – Part 7: Accuracy of axes of rotation) and supports calibration workflows compliant with ISO/IEC 17025:2017 Clause 6.4 (Equipment) and Clause 7.7 (Uncertainty of measurement). While not certified to NIST-traceable documentation by default, each unit is supplied with a factory calibration report listing measured face-to-face angles, flatness maps, and perpendicularity deviations—fully editable for integration into accredited lab quality management systems (QMS).
Software & Data Management
No embedded software or firmware is included—consistent with its role as a passive, artifact-based standard. However, the calibration report data (angle deviations, uncertainty contributions, flatness Zernike coefficients) is delivered in CSV and PDF formats, structured for direct import into metrology data analysis platforms such as M3 (Metrology Management System), PC-DMIS angular module, or custom Python/MATLAB uncertainty propagation scripts. The report includes full traceability statements referencing internal master polygons calibrated against national metrology institute (NMI) standards, and supports audit readiness for FDA 21 CFR Part 11-compliant environments when paired with validated electronic record systems.
Applications
- Periodic verification of optical dividing heads and indexing tables per ASTM E2919-19 (Standard Practice for Calibration of Rotary Tables).
- Uncertainty evaluation of high-resolution angular encoders used in semiconductor lithography stages and synchrotron beamline positioning systems.
- Reference standard in national metrology institutes for establishing angular scale transfer chains.
- Validation of multi-axis CMM kinematic models where pitch/yaw errors dominate volumetric accuracy budgets.
- Research-grade angular metrology in gravitational wave detector alignment systems requiring sub-arcsecond repeatability over thermal cycles.
FAQ
What distinguishes an odd-faced polygon (e.g., 17- or 23-face) from an even-faced one?
Odd-faced polygons generate non-commensurate angular subdivisions that decorrelate harmonic errors in rotary axis motion—enabling joint estimation of both large-period (e.g., bearing geometry) and small-period (e.g., encoder interpolation) components via Fourier analysis of face reversal measurements.
Is this polygon suitable for in-situ calibration on production floor equipment?
Yes—its robust GCr15 construction and 17 mm thickness provide thermal mass sufficient for short-duration shop-floor use; however, optimal performance requires temperature stabilization at 20 °C ±0.5 °C and isolation from vibration sources per ISO 230-7 Annex B.
Can I request NIST-traceable calibration documentation?
Third-party NIST-traceable calibration is available upon request through authorized metrology service providers; lead time and cost vary based on required uncertainty level and face count.
How often should a Grade 1 polygon be recalibrated?
Annual recalibration is recommended for accredited labs; biennial intervals may be justified under controlled environmental conditions with documented stability monitoring per ISO/IEC 17025 Clause 7.7.3.
Does the central φ25 mm bore meet ISO 7388-1 toolholder interface specifications?
No—the bore is designed for press-fit or clamping on precision spindles, not for toolholding; it does not include flange features, keyways, or taper compliance required by ISO 7388-1.
