Metrology Special Applications

metrology special applicationsApart from complete range of standard granite and cast iron metrology dimensional inspection equipment, GMT’s Metrology Division also manufactures metrology special applications  like master square for alignment of machining center, large size granite plates and granite base structures for Special Purpose Machines.



Certain minerals present in the granite are the cause of its typical colour. Also, the presence of these minerals on the working surface of a surface plate, or other metrology artefact, can cause problems. If they are very hard and brittle (quartz for e.g.) they can wear quickly leaving pitted areas on the surface.

selecting-graniteBesides, it is an acknowledged fact that pure black granite from the Deccan plateau in the South India is most resistant to wear. This does not mean that other colours do not have metrology characteristics. Furthermore, as granite is a natural material and its properties can vary from vein to vein in the quarry, it is best to test the stone periodically for its properties. Experts from GMT visit quarry to select the granite best suited for metrology.

Besides, granite used in metrology special application are made from select granite with uniform distribution of light and dark constituents. In such granite the distribution of minerals are even resulting in a homogenous appearance.
Texture : Fine
Specific Gravity : 3.08 g/cm3
Hardness : Scleroscope over 90
Modules of Elasticity : 9.0 to 12.0 x 105kg/cm2
Moisture of absorption : Nil


Our collaborative work with top level professors at IIT, Madras, resulted in the first Indian Standards for surface plate calibration. Fifty years down the road, GMT continues to maintain its focus on quality engineering excellence. As a result, the company has earned the trust of its customers and a premier place in the market.

As a result of GMT’s experience in the production of machine tools and dimensional reference equipment over three decades, we are able manufacture a wide variety of metrology special applications.

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