Why use natural granite?

Thermal expansion

Temperature fluctuation creates measurement errors

Thermal expansion is a phenomenon which occurs when a body (liquid, gaseous or solid) increases in volume as a result of an increase in temperature. This increase is caused by oscillation variation of the atoms around the equilibrium point.

The increase in temperature can influence a solid’s length, surface or volume.

Thermal expansion with temperature variation and thermal expansion coefficient presents errors in measuring machines.

Understanding the behaviour of various building materials is extremely important At Elbo Controlli NIKKEN, we dedicate time and resources to test and approve the use of granite for our presetters and optical scales.

What happens if a part in CARBON STEEL (e.g. the prismatic sliding guides or the spindle body) is rigidly fixed to a structure made of NATURAL GRANITE?

The immediate answer would be measurement errors due to different material behaviour. BUT IT’S WRONG!!

GRANITE is a material with a low coefficient of thermal conductivity (excellent insulator) therefore its temperature varies very slowly as the temperature of the surrounding environment changes (high thermal stability): in conclusion, NATURAL GRANITE is the material par excellence in construction of measuring machines for its chemical / physical and mechanical characteristics.

For years now, NATURAL GRANITE has been the preferred choice of manufacturers who produce three-dimensional measuring machines to guarantee more precise measurements and stability over time.

Temperature variations the presets undergo during the day can alter measurements and negatively affect the final result. Having a stable presetter is paramount.

All Elbo Controlli NIKKEN presetting machines use NATURAL GRANITE for both the base and for the column.

No need for geometric compensation through software, Elbo Controlli NIKKEN presetters will amaze you with their precision and consistency. Seeing is believing.

Thermal expansion on Elbo Controlli NIKKEN presetters