Granite Measuring Table

The Granite Measuring Table is a high-precision measurement reference tool made of natural granite as the core material and precision processed. ......

Granite 90° angle square Granite Straightedge Granite Square

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PRODUCT DETAILS

Technical Parameter

specifications（mm）	accuracy class
000 level flatness	00 level flatness	0 level flatness	1 level flatness
Flatness Tolerance（um）
300×300×70	1.5	3	5.5	11
300×400×70	1.5	3	6	12
400×400×70	2	3.5	6.5	13
400×500×100	2	3.5	7	14
400×600×100	2	3.5	7	14
400×630×100	2	3.5	7	14
450×600×100	2	3.5	7	14
500×600×100	2	3.5	7	14
500×800×100	2	4	8	16
600×900×100	2.5	4.5	9	18
600×900×130	2.5	4.5	9	18
1000×630×150	2.5	4.5	9	18
1000×750×150	2.5	4.5	9	18
1000×1000×150	2.5	5	10	20
1000×1500×200	2.9	5.7	11.3	22.6
1000×1600×200	3	6	12	24
1000×2000×200	3.5	6.5	13	26
1500×2000×200	3.5	7	14	28
1500×2000×300	3.5	7	14	28
1500×3000×300	3.5	7	14	28
2000×3000×300	4.5	8	18	36
2000×4000×400	5.5	11	22	44

The Granite Measuring Table is a high-precision measurement reference tool made of natural granite as the core material and precision processed. It is widely used in mechanical manufacturing, precision measurement, aerospace and other fields, providing a stable and reliable plane reference for size detection, form and position error measurement, and equipment calibration of various workpieces. The following provides a detailed introduction from the aspects of material characteristics, core advantages, precision levels, application scenarios, and usage precautions:

1、 Material characteristics and processing technology

Core materials: natural granite is mainly used, among which "Jinan Green", "Mount Taishan Green" and other varieties are most commonly used. This type of granite has the following natural advantages:

Uniform structure: The crystal particles are fine and evenly distributed, without defects such as pores or cracks, ensuring stable surface accuracy after processing.

Excellent physical properties: Mohs hardness reaches 6-7 levels (higher than cast iron), strong wear resistance, and long-term use is not prone to scratches or deformation.

Good chemical stability: resistant to water, oil, and general acid and alkali corrosion, without the need for regular rust prevention treatment like metal platforms.

Non magnetic: Non magnetic, avoiding interference with magnetic workpieces or measuring instruments (such as magnetometers).

Good shock absorption: It has certain damping characteristics and can absorb external vibrations, reducing measurement errors.

Processing technology: It requires multiple precision processes, including:

Raw stone cutting: Cut into blanks according to the required size;

Rough and fine grinding: remove surface defects and initially improve flatness;

Manual scraping or CNC grinding: By manual scraping (commonly used on high-precision platforms) or precision CNC equipment grinding, the surface flatness can reach micrometer level accuracy;

Chamfering and Polishing: Chamfering treatment is applied to the edges to prevent chipping, and the surface roughness can be reduced to Ra0.02 μ m or less after polishing.