Marble square is a precision marble measuring tool to detect the straightness, parallelism and perpendicularity of workpieces. Granite square is a precision benchmark measuring tool made of natural stones such as "Jinan Green", "Mount Taishan Green", "Mount Taishan Qingbaili", which are machined and manually ground. These stones have the characteristics of precise structure, good stability, uniform texture, large strength, high hardness, and also have the advantages of non rusting, acid and alkali resistance, wear resistance, non magnetization, unchanging, easy maintenance, easy cleaning, etc. Granite square ruler is mainly used to detect the straightness, parallelism, and perpendicularity of high-precision components, and is an ideal testing reference surface. Other supporting products include marble square rulers, marble flat rulers, marble parallel gauges, etc.

The material advantages of marble rulers: Marble rulers are made from high-quality underground rock layers that have undergone billions of years of natural aging. Their organizational structure is uniform, their coefficient of linear expansion is extremely small, and their internal stress is completely eliminated. Therefore, granite rulers have the characteristics of non deformation and high accuracy. The main mineral components are pyroxene, plagioclase, a small amount of olivine, biotite, and trace magnetite. The stone selected through strict physical and chemical experiments has a hard texture, fine crystal structure, excellent wear resistance, and good acid and alkali resistance, which can adapt to a wider range of working environments compared to cast iron measuring tools. Due to the non-metallic material used in granite rulers, rock like flat plates have little magnetic reaction or plastic deformation. Their hardness is 2-3 times higher than that of cast iron materials (equivalent to HRC>51). In use, even if a marble ruler is hit by heavy objects, at most a few fragments will fall off, and it will not damage accuracy due to deformation like metal tools. The marble square ruler is manually ground, and its surface smoothness is extremely high. It can move smoothly during measurement without any roughness.

2. Although the marble ruler will not deform or affect its accuracy due to the impact or knocking of hard objects, when the hard object hits its working surface, the marble ruler will drop stone slag and produce pits. If there are too many or too many pits on the working surface, it will affect the accuracy of the marble ruler. Therefore, when measuring workpieces or using them, attention should be paid to handling them gently to avoid too many pits, which will affect their use and appearance.

2. Marble square ruler is resistant to acid, alkali, corrosion, and magnetism;

3. After long-term natural aging, the internal stress of the marble square ruler completely disappears, the material is stable, and it will not deform;

4. The expansion coefficient of Dali stone is small, and it is less affected by temperature.

5. Marble rulers will not get damp or rust, and are easy to use and maintain;

Product Specification and Parameter Table