Proceq Equotip 550 Operating Instructions Manual page 23

3.3.3.4 Test Conditions
To ensure proper hardness readings, the following conditions must be fulfilled. If one or more conditions are not met, the result may be misleading.
Probe setup
Minimal required thickness
Minimal required weight
Required surface roughness
Acceptable surface curvature
Minimum space
Indentation size on test surface
300 HV, 30 HRC
600 HV, 55 HRC
800 HV, 63 HRC
Table 4: UCI Test Piece Requirements
© 2016 Proceq SA
Grade class
Maximum roughness
Average roughness
Indentation to edge
Between indentations
Depth
Diagonal
Depth
Diagonal
Depth
Diagonal
HV1 (~10 N)
5 mm / 0.2 inch
0.3 kg / 0.66 lbs
N8
15 μm / 600 μinch
3.2 μm / 125 μinch
Radius > 3 mm
5 mm / 0.2 inch
3 mm / 0.12 inch
11.3 μm / 445 μinch 25.3 μm / 996 μinch
79.1 μm / 3114 μinch 177.1 μm / 6972 μinch
8 μm / 315 μinch 17.9 μm / 705 μinch
56 μm / 2205 μinch 125.3 μm / 4933 μinch
6.9 μm / 272 μinch 15.5 μm / 610 μinch
48.3 μm / 1900 μinch 108.5 μm / 4272 μinch
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Table of Contents
HV5 (~50 N)
N10
60 μm / 2400 μinch
12.5 μm / 500 μinch
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