It has always been Saint-Gobain’s recommendation that Resinoid Bonded grinding wheels be used up within 2 years from the date of manufacture. This recommendation assumes that Resinoid Bonded grinding wheels have been stored under ideal storage conditions. It may be true under ideal storage conditions Resinoid Bonded grinding wheels can survive without any degradation in strength for well over two years. However, it is always wise to suspect any wheels over two years old and have them reinspected or re-speed tested to determine if there has been any degradation in strength. If the wheels are stored under less than ideal conditions, they may have a much shorter shelf life depending upon the severity of storage conditions.
These same comments also apply to rubber and shellac bonded grinding wheels. As for vitrified grinding wheels, the shelf life is less influence by humidity and adverse storage conditions as compared to resinoid, rubber or shellac, but even vitrified grinding wheels do not have an infinite shelf life.
The best procedure and the best rule of thumb is to have any wheel that is two years old or older re-speed tested and reinspected to ensure it is fit for use. The procedure for having this done and the charges are better explained by our Customer Service Department, but the cost of shipping as well as the cost of reinspection is the customer's responsibility. Also, any wheels rejected or otherwise lost in the reinspection process will also be the responsibility of the customer.
Keep in mind, however, that this procedure is good to verify the reliability of a product but must not be performed until you are ready to consume the wheel. If wheels are sent back after the two year time frame for reinspection and retesting and then put back on the shelf, there is no telling how long they will be fit for use after that last inspection. Therefore, these wheels must be consumed as soon as practical.
Click here to read about Proper Grinding Wheel Storage.
For additional information on this topic or if you need any other abrasive safety information, please review ANSI, OSHA and all literature provided by the abrasive wheel and machine manufacturer. You may also contact the Saint-Gobain Product Safety Department at Tel: (508) 795-2317 or Fax: (508) 795-5120 or contact your Saint-Gobain Abrasives, Inc. representative with any safety related questions.