1. Whenever the first two tests of the indenter and the test bench are replaced, there is often distortion, so it is not suitable.
2. The number of tests on each test piece shall be not less than three times. Each reading is recorded. The data processing can use the reading range as the hardness value of the tested piece, or the arithmetic mean of the three readings can be used as the hardness value.
3. The distance between the center of each indentation on the test piece and the distance from the center of the indentation to the edge of the test piece shall not be less than 3 mm.
4. When the initial test is applied, the test piece is only allowed to move upwards until the initial test force is added. It must not be returned halfway and continue to move upwards.
5. After the total test force is applied, the time should be kept for 10 seconds. The test piece with high hardness can be shortened properly, but for the test piece with low hardness, it should not be less than 10 seconds, otherwise it will affect the correctness of the test result.
6. When using the hardness block of this machine to calibrate the hardness, the hardness block is strictly forbidden to use on both sides. Only one side is allowed. Because the indented side has residual deformation of the metal, it will affect the calibration of the hardness tester.
7. The distance between the spherical surface of the hanging plate (15) and the tapered surface of the hanging sleeve (14) should be kept a certain distance. After the initial test force is applied, the spherical surface of the hanging plate (15) and the tapered surface of the hanging sleeve (14) should be made. Do not touch, otherwise the nut (16) should be loosened for adjustment.
8. When testing the bending plane hardness, the measured hardness value should be corrected according to the additional correction amount in Table 3 and Table 4. For example, when the test piece plane is a concave plane, the measured hardness value is added according to the correction amount of Table 3 and Table 4; when the surface of the test piece to be tested is a cylindrical surface or a convex surface, the measured hardness value, Subtracted according to the correction amount of Table 3 and Table 4. When the test piece is a sphere, the measured hardness value is subtracted from the correction amount of Table 5.
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