Precision machinery stone part

Granite is mainly composed of pyroxene, plagioclase, olivines, biotite and trace magnetite, black gloss, sophisticated structure, after millions of years of aging, uniform texture, good stability, high strength, high hardness, can be under heavy load to maintain high precision. Used in industrial production and laboratory measurements. Granite platform [1 ] granite platform precision reference to advanced national standards, in accordance with the GB4987-85 standard tolerances:: 000 = 1 x ( 1+d / 1000 ) um 00 = 2 x ( 1+d / 1000 ) um 0 = 4 x ( 1+d / 1000 ) um 1 = 8 x ( 1+d / 1000 um ( D ) to mm ( diagonal ) measuring temperature at 20 + / - 2 DEG C: physical properties of granite plate granite slab proportion: 2970-3070kg / square meters, compressive strength: 245-254N / m square meters, linear expansion coefficient: 4.61 x 10-6 / C, bibulous rate: < 0.13%, shore hardness: more than Hs70 granite formation of granite platform based on high-quality underground rock layer, after millions of years of natural aging, the shape is extremely stable, don't worry because of the conventional temperature difference and deformation. After the strict physical test and selection of the granite stone, fine crystal, hard texture, the compressive strength of 2290-3750 kg / cm2, hardness of the Mohs hardness grade 6-7. Extremely wear resistant, acid, alkali resistance, high corrosion resistance, never rust. Because the marble is non-metallic materials, no magnetic response, no plastic deformation. Its hardness is higher than cast iron 23 times ( the equivalent of HRC > 51 ), so to maintain good accuracy. In use rock tools even by heavy Kepeng, falls several grain of ballast at most, and not as metal tools that, due to deformation and damage of precision. Its superior quality iron and steel manufacture precision measuring datum parts, can obtain high accuracy and stable