Modes of ball examination
The sorting machine is able to check the surface and subsurface of the bearing ball on the basis of a spherical motion that the ball performs in the monitoring point – so called “meridian marking”. During this spherical movement the EOT and ECT testers check the surface and subsurface of the monitored ball along the meridian lines. The number of meridians varies for each ball diameter and is directly dependent on the diameter of the ferrite core used in the ECT tester. For most applications a StanDard (STD) meridian pitch that is set by the manufacturer is used – therefore, we say in such circumstances that the machine is working in STD mode. For more demanding applications (according to customers requirements) each machine may also be switched to AeroSpace (AS)mode, which has a tighter meridian pitch.
Control mode STanDard (STD)
Control mode STanDard which is marked STD is for moderately demanding usage. The meridian pitch on the equator is set by the manufacturer in relation to the diameter of the ferrite cores of the ECT tester to ensure that every area on the ball is checked
Checking Mode AeroSpace (AS)
The checking mode AS is characterised by a narrowed meridian pitch on the equator, which improves the resolution of the eddy-current tester ECT and, in the case of the EOT tester, the sensitivity of the optical method (mainly on Ball Scanners Wet)