Grinding Wheel Dressing

Grinding wheel dressing refers to the use of diamond pen or diamond wheel will pass the appearance of some of the removal process.When does the grinding wheel need to be trimmed? Mainly including three conditions:
1.The new grinding wheel just install on the machine, the outer circle must not round, need to be rounded.
2.The appearance has a layer of abrasive passivation after grinding, then we need remove this layer of abrasive.
3.The grinding wheel itself is not passivated, but because of the grinding of the material in the grinding wheel appearance so that it can no longer continue to grind.
Dressing speed is not the same will directly affect the roughness of the wheel surface, and then the impact the workpiece processing. So sometimes the same workpiece roughness can be used with the same piece of grinding wheel through a different dressing speed to reach.