Granite/Marble Plates: Core Carrier for Precision Industrial Datums and Stable Support Across Industries

Overview of the Solution

This granite/marble plate, centered on “high precision of natural materials, stability in all environments, and versatility in multiple scenarios”, addresses the pain points of traditional metal plates such as “significant thermal deformation, susceptibility to rust, and rapid precision degradation”. It provides a one-stop datum solution covering “basic datum support, precision inspection assistance, and machining assembly positioning”.

Leveraging the ultra-low thermal expansion coefficient (granite: 5-8×10⁻⁶/℃; marble: 6-9×10⁻⁶/℃), excellent vibration resistance (vibration attenuation rate ≥85%), and wear-resistant properties of high-density natural stone, it serves as a long-term stable datum platform for industries including precision manufacturing, metrology and testing, electronic semiconductors, and aerospace. It ensures a flatness error of ≤0.003mm/1000mm and a precision retention period of 5-8 years, helping enterprises improve the reliability of inspection data by 30% and reduce equipment maintenance costs by 60%.

Core Function System

1. Micron-Level Precision Datum Support

• Ultimate Flatness Datum: High-density Jinan Green granite (quartz content ≥65%, feldspar ≥25%, no visible impurities) or high-purity marble (calcium carbonate content ≥95%) is selected and processed through a three-stage process of “rough grinding – fine grinding – nano-polishing”. The flatness accuracy reaches Grade 00 (≤0.003mm/1000mm), Grade 0 (≤0.005mm/1000mm), and Grade 1 (≤0.01mm/1000mm). The surface roughness is Ra≤0.02μm (for granite) and Ra≤0.05μm (for marble), providing a unified datum for precision inspection tools such as dial indicators, micrometers, and coordinate measuring machines, and avoiding inspection errors caused by datum deviation of metal plates.
• Full-Range Uniform Load-Bearing: The plate has an integral structure without splicing (maximum single-piece size: 4000×6000mm), with a surface load-bearing capacity of 500-2000kg/m² (adjustable according to thickness). The full-range flatness error fluctuation is ≤0.002mm, adapting to the stable placement of micro-precision parts (e.g., semiconductor chip carriers) as small as 5mm and large parts (e.g., machine tool guideways) as large as 2m, eliminating workpiece tilt or inspection deviation caused by local depression.
• Precise Marking Assistance: Precision scale lines (line width 0.1mm, spacing accuracy ±0.005mm) or positioning grids can be laser-engraved on the plate surface as required. When used with marking needles and squares, it enables dimensional marking and contour calibration of precision parts. The marking accuracy is 40% higher than that of metal plates, reducing the rework rate of subsequent machining.

2. Guarantee for Stable Operation in All Environments

• Ultra-Low Thermal Deformation Control: The thermal expansion coefficient of natural stone is only 1/2 that of cast iron (cast iron: 11×10⁻⁶/℃). Under an ambient temperature fluctuation of -20℃ to 60℃, the dimensional change of a 1m-long plate is ≤0.001mm, avoiding datum tilt caused by temperature changes. It is particularly suitable for temperature-sensitive scenarios such as electronic semiconductor workshops (constant temperature ±1℃) and precision testing laboratories.
• Efficient Vibration Isolation: The internal damping coefficient of granite/marble is 3-5 times that of cast iron, which can absorb high-frequency vibrations (50-3000Hz) generated by machine tool operation and personnel movement in the workshop. The vibration amplitude is reduced from 0.015mm (for metal plates) to 0.003mm, reducing the interference of vibration on precision inspection data (e.g., roundness inspection, parallelism calibration), and the inspection repeatability error is reduced by 60%.
• Corrosion Resistance and Wear Durability: The stone surface is dense and non-porous, capable of withstanding commonly used industrial reagents such as alcohol, acetone, and cutting fluids, without the rusting and oxidation problems of metal plates. The surface hardness reaches HS70-80 (for granite) and HS55-65 (for marble), and the wear resistance is more than twice that of cast iron plates. After long-term use (≥100,000 workpiece placement frictions), the surface wear is ≤0.001mm, eliminating the need for frequent regrinding, and the maintenance cycle is extended to more than 2 years.

3. Universal Adaptation to Multiple Scenarios

• Precision Inspection Scenarios: Serving as a datum platform for metrology and testing institutions to calibrate gauge blocks, calipers, and micrometers, or as a carrier for enterprises to inspect the roundness of shaft parts and the parallelism of flat parts. When used with roundness meters and levels, high-precision inspection can be completed, and the qualification rate of inspection data is increased to 99.5%.
• Machining Assistance Scenarios: Acting as an auxiliary support platform for workpieces in CNC machine tools and grinding machines, providing stable support for large or thin-walled parts (e.g., aluminum alloy housings, stainless steel thin plates), avoiding workpiece deformation during machining. The surface roughness of machined parts is reduced from Ra1.6μm to Ra0.8μm.
• Assembly Positioning Scenarios: Used for the assembly positioning of mechanical components (e.g., gearboxes, motor end covers). The flatness of the plate ensures the docking accuracy of components. When used with positioning pins and clamps, coaxial assembly of multiple components can be achieved, the assembly efficiency is increased by 30%, and the subsequent debugging time is reduced.

Core Composition of the System

Typical Industry Application Cases

1. Metrology and Testing Field: Used by a provincial metrology institute for calibrating Grade 0 gauge blocks —— A Grade 00 granite plate (800×600mm) is selected, with a surface roughness of Ra≤0.01μm. The repeatability error of gauge block calibration is reduced from ±0.001mm to ±0.0005mm, meeting the highest requirements of the verification regulation JJG 146-2011 “Gauge Blocks”, and the annual calibration volume is increased by 20%.
2. Precision Bearing Industry: Used by a bearing enterprise for inspecting the roundness of bearing inner ring raceways —— A Grade 0 granite plate (1000×800mm) is adopted, and when used with a roundness meter, the inspection error is reduced from ±0.003mm to ±0.001mm. The qualified rate of finished bearings is increased from 97% to 99.8%, reducing the loss caused by defective products.
3. Semiconductor Equipment Industry: Used by a semiconductor manufacturer for debugging the guideway parallelism of wafer cutting equipment —— An anti-magnetic granite plate (1500×1200mm) is selected, with a thermal deformation of ≤0.0008mm/m. The guideway parallelism error is controlled within ≤0.002mm, and the wafer cutting yield is increased from 95% to 98.5%, meeting the processing requirements of 7nm chips.
4. Construction Machinery Industry: Used by a heavy industry enterprise for assembling excavator hydraulic valve blocks —— A Grade 1 marble plate (2000×1500mm) is used, and the coaxiality error of valve block docking is reduced from ±0.01mm to ±0.003mm. The leakage rate of the hydraulic system after assembly is reduced by 50%, and the service life of the equipment is extended by 2 years.

Core Competitive Advantages

• Far Superior Precision Retention Than Metal: Natural stone is formed over hundreds of millions of years, with a stable internal structure, and does not have the stress release and plastic deformation problems of metal plates. The precision retention period is 5-8 years (only 1-2 years for metal plates), reducing downtime for frequent calibration and saving enterprises more than 200 hours of operation and maintenance costs annually.
• Extremely Low Maintenance Costs: No painting or rust-proof treatment is required for the surface; daily maintenance only involves wiping with a dust-free cloth, avoiding the maintenance costs of regular rust removal and re-scraping of metal plates (the annual maintenance cost of metal plates is approximately 2,000 yuan, while that of stone plates is only 200 yuan). The full-life cycle cost is reduced by 80%.
• Wide Environmental Adaptability: It can be used for a long time in humid environments (relative humidity ≤90%) and slightly corrosive environments (e.g., electronic workshop cleaning agents, mechanical processing cutting fluids) without the risk of rusting and corrosion of metal plates. Its anti-magnetic property makes it suitable for inspecting magnetic parts (e.g., motor cores, magnetic steels), avoiding magnetic field interference.
• Higher Cost-Effectiveness: Although the initial purchase cost is 20%-30% higher than that of ordinary cast iron plates, combined with a 5-8 year service life and extremely low maintenance costs, the full-life cycle cost is 40% lower than that of metal plates. It is particularly suitable for scenarios requiring long-term precision datums.

Full-Dimensional Customization Services

• Basic Customization:
• Size Customization: The length and width of the plate can be designed from 300×300mm to 5000×8000mm (splicing is available for extra-large sizes, with a flatness error of ≤0.003mm at the splicing joint), and the thickness can be designed from 50mm to 300mm as required. The maximum load-bearing capacity can reach 3000kg/m².
• Precision Customization: Grade 00 (highest precision, suitable for metrology calibration), Grade 0 (suitable for precision inspection), and Grade 1 (suitable for regular machining/assembly) are available to meet the precision requirements of different scenarios.
• Function Extension Customization:
• Structure Customization: Processing of positioning grooves, mounting holes, and T-slots (suitable for fixing inspection fixtures or workpieces), or customization of special-shaped plates with steps (to meet the support of workpieces of multiple heights).
• Surface Treatment: Ultra-smooth treatment (Ra≤0.01μm, suitable for optical inspection), sandblasting anti-slip treatment (suitable for placing heavy parts), and anti-magnetic treatment (suitable for strong magnetic environments, such as motor inspection).
• Supporting Service Customization:
• Installation and Debugging: Provide on-site horizontal calibration services to ensure the horizontal accuracy of the plate is ≤0.001mm/m, and match with adjustment pad irons to achieve rapid leveling.
• After-Sales Guarantee: Provide a 2-year free warranty and lifelong precision calibration services (the calibration cycle can be customized to 1 year/2 years), and issue an inspection report after calibration.
• Supporting Procurement: Inspection fixtures, dust-proof constant temperature covers, and handling equipment can be customized simultaneously, providing a one-stop procurement solution of “plate + auxiliary equipment”.