Facing Operation. Facing is the process of removing metal from the end of a workpiece to produce a flat surface. Most often, the workpiece is cylindrical, but using a 4-jaw chuck you can face rectangular or odd-shaped work to form cubes and other non-cylindrical shapes
3) In a lathe, facing operation is used for producing
A plane surface
Related Diploma CET Mechanical Question Paper - 2018 with Answer Key
Any odd-shaped workpiece to locate the axis of rotation
Faceplates are used to hold work that is too large or of such a shape that it cannot be held in a chuck or between centers. Faceplates are equipped with several slots to permit the use of bolts to secure the work, so that the axis of the workpiece may be aligned with the lathe centers. When work is mounted off – center, a counterbalance should be fastened to the faceplate to prevent imbalance and the resultant vibrations when the lathe is in operation.
Boring Boring is an operation of enlarging a hole that has already been drilled. Boring is done by a single point cutting tool.
Trepanning is an operation of producing a hole by removing metal along the circumference of a hollow cutting tool.
Up Milling is the process of removing metal by a cutter which is rotated against the direction of travel of the workpiece is called up-milling. It is also called conventional milling.
In up-milling, the chip thickness is minimum at the beginning of the cut and maximum at the end of cut. The cutting force varies from zero to maximum.
Down Milling is the process of removing metal by a cutter which is rotated in the same direction of travel of the workpiece is called down milling. It is also called climb milling.
In down milling, the chip thickness is maximum at the beginning of the cut and minimum at the end of cut. The cutting force varies from maximum to zero.