• The wheels are typically made with a bonded abrasive.


• common abrasives used are,

Aluminum oxide

Silicon carbide


• Grain size is typically from 6 to 600.


• The bonding mechanisms used commonly are,

- vitrified

- resinoid

- rubber

- shellac

- silicate


• The Grade of the wheel is a measure of the ability to retain grit. If a wheel is Grade A it is soft, if it is Grade Z, it is very hard.


• The wheels are also given a structure number. 1 indicates a dense structure, whereas, 15 indicates an open structure.


• Loading of a wheel refers to the embedding of swarf in the voids.


• Glazing occurs when the grit has dulled, but is still bonded to the surface.


• Grinding wheels should undergo a dressing process.


• Many grinding wheels are shaped. This shaping is done while the wheel in the machine using diamond, or other hard shaping tools.



1.3.1 Operation Parameters


• The wheel can be made to act soft by increasing work speed, and decreasing wheel speed. The wheel can be made to act hard by reversing the parameters.


• Typical operation parameters are a depth per pass.



• The wheel normally turns to give a CS of 3500 to 6000 fpm and wheels range from diameters of a few inches to a few feet.


• The table feed is 80-350 fpm for finishing passes. Up to 1000 is reasonable.


• For surface grinding