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Product Description

 The advantages are high precision, no static electricity, durability, high measurement accuracy. The shape of the working surface includes rectangles, squares, circles, etc. Besides, V-shaped, T-shaped, U-shaped grooves, dovetail grooves, round holes, long holes, etc. These also can be machinable. It is a flat reference measuring tool for workpiece, equipment inspection, scribing, assembly, welding, assembly, and riveting.

Working principle

 Generally used as a reference positioning surface in testing. Work surface is as a planar reference for inspection and scribing. Use this datum surface to compare with the actual surface of the workpiece being tested to determine the error value. The standard specifications of the granite surface plate are flat and the granite surface plate can also be slotted or perforated. Our company can make components or bases according to user requirements.

Skills requirements

1.  There should be no defects such as sand holes, pores, cracks, slag inclusions, shrinkage, scratches, bumps, rust and other defects that seriously affect the appearance and performance of the working surface of the granite surface plate.

2. The depression or corner on the non-working surface of the granite surface plate allows repairing.

3. The granite surface plate should be made of fine-grained, densely structured gabbro, diabase, granite (the biotite should be less than 5%, the elastic modulus should be greater than 0.6x10-4kg/cm 2 , and the water absorption should be less than 0.25%). The hardness of the working surface should be greater than 70hs.

4. The allowable value of the surface roughness R of the working surface is 0.32—0.63μm, and the side is 10μm.

5. The vertical tolerance of the side of the granite surface plate to the working surface and the vertical tolerance of the adjacent sides of the plate are in accordance with the 12th level specified in GB/T1184.

 6.