Wheel Inspection |
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Do not assume that a wheel is in sound condition just because it is
To inspect a wheel for damage:
1.Remove wheel flange and sleeve, then look for any cracks, chips, nicks, or dents in wheel surface. If you see any of these, DO NOT attempt to use wheel.
2.Do a ring test. This test will give you an indi- cation of any internal damage that may not be obvious during a visual inspection.
3.Inspect paper washers on both sides of grind- ing wheel (see Figure 28).
These washers are cushions between wheel sleeve and flange and grinding wheel. Without paper washers, cracks can be spawned from center of wheel when the arbor nut is tight- ened. Over time, these cracks can radiate outward and the wheel may explode during operation, possibly causing injury.
Paper Washer
Figure 28. Important wheel paper washer.
Note: If you need to replace or install new paper washers, replacements can be cut out of any thick construction paper or card stock. Regular notebook paper or paper from a copy machine is not acceptable, as it is too thin to provide required cushion. Be sure to transfer any RPM limitations and wheel type informa- tion to the new paper washers.
This test will give you an indication of any internal damage that may not be obvious during a visual inspection.
To perform a ring test:
1.Make sure wheel that you test is clean and dry; otherwise, you may get false results.
Note: If wheel is wet with coolant, hang it in a dry location until it is dry (usually overnight).
2.Remove wheel flange and sleeve.
3.Hang wheel in air with a piece of cord or string looped through wheel bore, as shown in Figure 29.
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