Product life is defined by several causes, such as physical life (break-down beyond repair), functional life (need for the product ceases), economic life (new products offer the same functionality at lower operating costs), legal life (regulations make the product illegal) [ASHB09, p. 66]. The most important causes for end of grinding tool life are tool wear to the minimum abrasive layer dimensions or tool degradation at the end of shelf life. Options for end of life are landfill, combustion, recycling, reengineering, or re-use [ASHB09, p. 67]. Reengineering and re-use are not feasible for most used abrasive tools and are not considered here.
4.8.1 Shelf Life and Transport
Grinding tools should be stored in dry, evenly tempered, frost-free rooms [BGI10]. Direct sunlight, uneven heating, bending, and vibrations during transport might lead to dangerous cracks [BGI10]. Large grinding wheels need to be moved by a crane with specific fixtures [BGI10].
Coated abrasive tools may contain organic material and may degrade with time [UAMA09]. One recommendation is to use grinding belts and discs within 10 years from the date of manufactured if stored under ideal conditions [UAMA09]. Before use, coated abrasives should be inspected and must not be used, if they appear brittle, curled, damaged, discolored, or of the joint can be pulled apart [UAMA09]. Tools with magnesite bonding age faster in humid environments [BGI10]. Vitrified grinding wheels have an almost infinite shelf life, but the chance of tool damage during storage still applies [UAMA09].