Granite is a type of igneous rock formed in the Earth millions of years ago. The composition of igneous rock contains many minerals, such as quartz which is extremely hard and wear-resistant. In addition to hardness and wear resistance, granite has approximately half the coefficient of expansion as cast iron. As its volumetric weight is approximately one-third that of cast iron, granite is easier to manoeuvre.
For machine bases and metrology components, black granite is the colour most used. Black granite has a higher percentage of quartz than other colours and is, therefore, the hardest wearing.
Granite is cost-effective, and cut surfaces can be exceptionally flat. Not only can it be hand-lapped to achieve extremes of accuracy, but re-conditioning can be performed without moving the plate or table off-site. It is entirely a hand-lapping operation and generally costs much less than re-conditioning a cast iron alternative.
These qualities make granite the ideal material for creating custom-size and custom-design machine bases and metrology components such as the granite surface plate.
Eley Metrology produces bespoke granite products that are created to support specific measurement requirements. These bespoke items vary from straight edges to tri squares. Due to the versatile nature of granite, the components can be produced in any size required; they are hard-wearing and long-lasting.
