Granite/Marble Circular Platforms: Exclusive Datum Carrier for Machining and Inspection of Circular Workpieces

Overview of the Solution

This granite/marble circular platform is specifically designed for the machining, inspection, and assembly of circular workpieces such as flanges, bearing housings, gears, and circular molds. With “precise adaptation to circular structures, 360° operation compatibility, and nanoscale symmetric datums” as the core, it overcomes the three major pain points of traditional square platforms: “difficult positioning of circular workpieces, interference in rotational operations, and poor control of symmetric precision”.

Leveraging the ultra-low thermal expansion coefficient (5-9×10⁻⁶/℃), uniform stress distribution, and excellent vibration resistance (vibration attenuation rate ≥85%) of high-density natural stone, it provides a full-circumferential stable datum for circular workpieces. It ensures a concentricity error of ≤0.002mm and a roundness inspection accuracy of ≤0.001mm, making it suitable for scenarios such as wind power flange machining, bearing precision inspection, and circular mold assembly. It helps enterprises increase the processing yield of circular workpieces by 35% and improve inspection efficiency by 50%.

Core Function System

1. Circular-Exclusive Datums and Rotational Adaptation

• Ultra-High Symmetric Precision Datums: High-density granite (quartz content ≥65%, density ≥2.7g/cm³) or high-purity marble (calcium carbonate content ≥98%, density ≥2.75g/cm³) is selected. Through the “CNC turning – multi-stage precision grinding – nanoscale polishing” process, the roundness of the platform top surface is ≤0.001mm/1000mm, the concentricity (between the central hole and the outer circle) is ≤0.002mm, and the surface roughness is Ra≤0.01μm. It provides a symmetric datum for circular workpieces, avoiding “corner interference” and “datum deviation” during positioning on square platforms.
• 360° Unobstructed Operations: The circular structure supports full-circumferential rotational machining or inspection of workpieces. When combined with an optional rotating support base, it can achieve continuous rotation at 0-10r/min, adapting to scenarios such as full-circumferential welding of flanges, full-tooth inspection of gears, and full-circumferential grinding of circular molds. There is no need for frequent adjustment of workpiece positions, and operation efficiency is increased by 40%.
• Precise Positioning of Circular Workpieces: A positioning hole (φ10-φ50mm, tolerance H6) is reserved at the center of the platform, where a central positioning pin can be installed to fix circular workpieces (e.g., bearing housings, wheel hubs). The top surface can be machined with annular T-slots (slot width 10-30mm, slot spacing 50-100mm). When used with pressure plates, it enables secure clamping of circular workpieces with different diameters (200mm-2500mm), and the positioning error is ≤0.003mm.

2. Guarantee for Stable Operation Under All Working Conditions

• Uniform Thermal Deformation Control: The thermal expansion coefficient of natural stone is uniform, and the full-circumferential dimensional changes of the circular structure after heating are consistent (for a platform with a diameter of 1m, the diameter change is ≤0.0008mm when the temperature fluctuates by 10℃). This avoids “datum tilt” caused by local heating of square platforms and ensures stable concentricity during the machining of circular workpieces (within a dimensional tolerance of ±0.002mm).
• Efficient Vibration Isolation: The internal damping coefficient of stone is 4-6 times that of cast iron, which can absorb high-frequency vibrations (50-3000Hz) generated during the rotational machining of circular workpieces (e.g., lathe cutting, grinder polishing). The vibration amplitude is reduced from 0.015mm (on metal platforms) to 0.003mm. Annular shock-absorbing pad irons (shock absorption efficiency ≥90%) are installed at the bottom of the platform to further isolate vibrations from the workshop floor, reducing the impact of vibrations on the roundness and cylindricity of circular workpieces.
• Corrosion Resistance and Wear Durability: The surface undergoes “phosphating + nano-ceramic coating” treatment (coating thickness 5-10μm), which can withstand industrial reagents such as cutting fluids, emulsions, and rust inhibitors, without the rusting and oxidation issues of metal platforms. The wear resistance of the top surface is 2.5 times that of metal platforms. After long-term use (≥100,000 rotational frictions of workpieces), the surface wear is ≤0.001mm, eliminating the need for frequent regrinding and extending the maintenance cycle to more than 2 years.

3. Multi-Scenario Integration and Adaptation

• Collaboration Between Machining and Inspection: Without replacing the platform, it can be adapted to both the machining of circular workpieces (e.g., flange drilling, gear hobbing) and precision inspection (e.g., roundness and concentricity calibration). Angle scale lines (accuracy ±0.1°) can be laser-engraved on the top surface of the platform. When used with a roundness meter and a dial indicator, inspection can be completed, reducing precision deviations caused by workpiece transfer.
• Integration of Auxiliary Functions: Annular cooling water channels (hole diameter 8-15mm) can be machined on the side of the platform to meet the heat dissipation needs during the machining of circular workpieces. The central positioning hole can be integrated with a vacuum suction interface (vacuum degree ≤-95kPa) for fixing thin-walled circular workpieces (e.g., stainless steel heads), avoiding workpiece deformation caused by clamping pressure.
• Equipment Docking Adaptation: Equipment mounting holes (evenly distributed along the circumference, hole position tolerance ±0.005mm) are reserved, which can be directly docked with equipment such as lathes, grinders, and rotating worktables to achieve integrated “platform – equipment” integration. This reduces datum errors caused by intermediate connectors and shortens the installation and commissioning time by 60%.

Core Composition of the System

Typical Industry Application Cases

1. Wind Power Flange Machining: Used by a heavy industry enterprise for drilling 3MW wind power flanges (diameter 2.5m) —— A granite circular platform (diameter 3000mm) is adopted. The annular T-slots are adapted to the full-circumferential clamping of the flange, with a concentricity error of ≤0.002mm. The drilling position error is reduced from ±0.02mm to ±0.005mm, the flange assembly qualification rate is increased by 35%, and the machining efficiency is increased by 40%.
2. Bearing Roundness Inspection: Used by a bearing enterprise for inspecting the roundness of precision bearing inner rings (diameter 50-200mm) —— A marble circular platform (diameter 800mm) is selected and used with a roundness meter. The inspection repeatability error is reduced from ±0.002mm to ±0.0008mm, the inspection efficiency is increased from 20 pieces/hour to 35 pieces/hour, and the inspection rework rate is reduced.
3. Circular Mold Assembly: Used by a mold enterprise for assembling automotive wheel hub molds (diameter 1.2m) —— A granite circular platform (diameter 1500mm) is used. The 360° rotating support base enables full-circumferential assembly of the mold. The platform flatness is ≤0.002mm/1000mm, the mold splicing gap is reduced from 0.01mm to 0.003mm, and the service life of the mold is extended by 2 times.

Core Competitive Advantages

• Strong Adaptability to Circular Workpieces: The exclusive circular structure avoids corner interference of square platforms, and 360° operation is compatible with full-circumferential machining/inspection of circular workpieces. The positioning accuracy is 50% higher than that of square platforms, making it particularly suitable for symmetric workpieces such as flanges, bearings, and circular molds.
• High Symmetric Precision Barrier: Both roundness and concentricity reach the nanoscale (Grade 00 precision), far exceeding that of metal circular platforms (Grade 0 precision). It is the only datum solution for precision circular workpieces (machining accuracy ≤0.005mm), meeting the needs of high-end fields such as aerospace and wind power.
• Excellent Long-Term Stability: After 24-36 months of natural aging treatment, more than 99.5% of internal stress is eliminated. The stress distribution of the circular structure is uniform, and the precision retention period is 5-8 years (only 2-3 years for metal platforms). This reduces downtime for frequent calibration and saves enterprises more than 200 hours of operation and maintenance costs annually.
• Low Comprehensive Cost: Although the initial purchase cost is 20%-30% higher than that of metal circular platforms, there are no rust prevention and regrinding maintenance costs of metal platforms, and the service life is extended by 2 times. The full-life cycle cost is more than 50% lower than that of metal platforms.

Full-Dimensional Customization Services

• Size and Structure Customization:
• Diameter Customization: 300mm-5000mm (extra-large diameters can be spliced, with a roundness error of ≤0.003mm at the splicing joint), thickness 80mm-500mm (adjusted according to load-bearing requirements);
• Structure Customization: Specifications of central positioning holes (φ10-φ100mm), number of annular T-slots (1-10) and spacing (30-200mm), accuracy of angle scale lines (±0.05°-±0.2°).
• Precision and Function Customization:
• Precision Grade: Grade 00 (roundness ≤0.001mm/m) for wind power flange machining/bearing inspection, Grade 0 (≤0.002mm/m) for conventional circular workpiece machining;
• Function Enhancement: Nanoscale surface polishing (Ra≤0.008μm), anti-static treatment (surface resistance 10⁶-10⁹Ω), integration of vacuum suction/annular cooling water channels to adapt to special scenarios.
• Installation and After-Sales Customization:
• Installation and Commissioning: On-site horizontal calibration (accuracy ≤0.001mm/m), collaborative debugging of rotating support bases and platforms to ensure rotational accuracy meets standards;
• After-Sales Guarantee: 3-year free warranty, lifelong precision calibration and maintenance, customizable “semi-annual inspection + biennial in-depth maintenance” programs;
• Supporting Services: Simultaneous customization of special fixtures for circular workpieces and inspection auxiliary tools, providing a one-stop solution of “platform + fixtures + inspection”.