A common practice among manufacturers is to provide information about the type of grit, hardness, wheel dimensions and the kind of bonding material used for every grinding wheel that is made. But there is no single standard as to how these information are provided. Different manufacturers will have their own way of using codes to provide these information.
One could not take a grinding wheel from one producer and substitute it for another brand of grinding wheel just because they have the same codes. Aside from the fact that it is very unlikely for various brands to have the very same system of codes, the distinctions in manufacturing processes lead to grinding wheels with varying quality and performance.
In any type of machining process, if you want the best results, you have to never try to use substitute parts without guidance from professionals that are knowledgeable about the machining process and different tool suppliers. In instances in which a certain design of grinding wheel has is no longer being produced and there is no other choice but to find an alternative, a series of trial and error may be needed to find the right replacement.