BEIJING TIME VISION AI INSTRUMENT LTD.
https://timetech-ndt.com/
Email: timehardnesstester@gmail.com
WhatsApp: 008615201625204
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TIME5300 Leeb hardness tester, G probe, for hardened workpiece.
To eliminate hardness errors resulting from the roughness of a sample’s surface, the test surface should be polished until its roughness Ra is no more than 1.6m. The test surface should be clean and free from oil stains.
4.2 Supporting and coupling of a test sample
1）For test samples weighing over 11 lbs (5 kg), no support is required..
2）Samples having a cantilever or thin shell shape and weighing between 4.4 to 11 lbs (2 to 5 kg) must be firmly supported by bearing supports weighing over 11 lbs (5 kg) in order to prevent bending, deformation or displacement due to the impact force.
3）Test samples weighing less than 4.4 lbs (2kg) should be firmly coupled to a support weighing over 11 lbs (5kg). The coupling surface between the sample and the support should be smooth without any surplus coupling fluid. The direction of impact should be perpendicular to the couple surface
4）Minimum weight of a test sample should be 0.2 lbs (0.1 kg) ，minimum thickness of a test sample should be 0.2 in (5mm) ，minimum depth of hardened layer should be 0.03 in (0.8mm).
5）The clamp is tight and the testing surface is perpendicular to impact direction.
When the test sample is a large plate, long bar or bend work piece, the impact force can cause a deformation or instability when the impact device is released. This may bring about an error in measurement, even if the weight or thickness of the test sample seems applicable. In this case, a reinforcement should be attached to the back of the sample surface opposite to the impact force.
7）Magnetism of test sample should be less than 30 Gauss.
4.3 Selection of support ring for inner/outer cylindrical/spherical surface
When testing a curved surface with a radius of curvature R less than 1.2 inch (30mm, using impact device D, DC, D+15, C, E or DL) or a radius of curvature R less than 50mm (using impact device G), a special small support ring should be used to compensate the curvature.
