Mumbai University > Mechanical Engineering > Sem 4 > Production Process II

Marks: 5M

Year: Dec 2014

Dressing:

Dressing removes loading and breaks away the glazed surface so that sharp abrasive particles are again presented to the work. This is done with various types of dressers. A common type of wheel dresser, known as the star dresser, consist of a number of a hardened steel wheels with points on the periphery. The dresser is help against the face of the revolving wheel and moved across the face to dress the whole surface. This type of dresser is used to dress coarse grain abrasive wheels used for rough snagging work. Abrasive wheel dressers operating at high speeds are frequently used to dress other wheels. They are used to dress wheels where a fair degree of finish is desired on the work. The diamond or group of diamonds is mounted in a holder. The diamond should be kept pointed, since only the point can be used for cutting. This is done by keeping the holder at a 15o angle and using a new surface each time the wheel is dressed.

Truing:

It is the process of changing the shape of the grinding wheel as it becomes worn from an original shape, owing to the breaking away of the abrasive and bond. This is done to make the wheel true and concentric with a bore or to change a face contour for form grinding. Truing and dressing is done with the same tools, but not for the same purpose.

The only satisfactory method of truing a wheel is by the use of a diamond tool in a similar manner as explained before. In truing a wheel with a diamond, the feed must not exceed 0.02mm otherwise grooves may be cut on the grinding wheel.