11:00 PM , Posted in Grinding Fixtures
The work holding devices for grinding operations will depend upon the type of the grinding operation and the machine used.
(A): Fixture for External Grinding:
A mandrel is the most common fixture used for grinding external surface of the work piece, a mandrel is hardened and is held between centers of a machine. The mandrel is used for internal chucking or round work piece with bores. The work piece is located and held on the mandrel with the help of the bore so that the external surface may be machined truly concentric to the bore. The various types of mandrel are:
> Taper Mandrel: In this type of mandrel, the outer chucking surface is given a slender taper of about 0.5mm per meter.
> Straight Mandrel: It differs from the taper mandrel in that it has straight or un tapered chucking surface.
> Combination taper and straight: In this type of mandrel , a portion of the outer diameter of the mandrel is straight and the rest of the is tapered.
B: Fixtures for Internal Grinding:
For grinding internal surfaces of simple circular work piece, the chuck may be used as a standard work holding device. It required special jaws can be provided for the chuck. However , for many components special fixtures may have to be made which are designed on same lines, as the lathe fixtures.
C: Fixtures for Surface Grinding:
The work piece can be held for machining on a surface grinder in the following ways
· It may be clamped directly to the machine table or to an angle plate and so on,
· It may be held in a vice.
· The work piece may be held by means of a magnetic chuck or a vacuum chuck. Here the work piece is held without any mechanical clamping.
· The work piece may be held in a special fixture.