MILLING MACHINE

INTRODUCTION

Milling is a machining process of removal of metal by feeding the work piece against rotating multipoint cutter. As the cutter rotate, each cutting edge removes small amount of material from the work piece. This process is used to generate flat surfaces or curved profile and many other complex shapes with great accuracy and having very good surface finish. Based on spindle position, milling machine are classified into horizontal milling machine and vertical milling machine.

HORIZONTAL MILLING MACHINE

BASE: It is the foundation for all other part of milling

machine. It give machine to required rigidity and strength.

COLUMN

BASE

COLUMN: It is the vertical member of the machine which supported by a table.

KNEE: It can slides up and down on the vertical guide ways of column. It supported by the elevating screw for adjusting the height of the knee.

SADDLE: It supports and carries the table. It adjusted on guide ways on the top of the knee.

TABLE: It support the work piece and it can move longitudinally.

ELEVATING SCREW: It support the knee and height of the knee adjusted with the help of elevating screw.

SPINDLE: it help to transmits power from motor to arbor. OVERARM: It is on the top of the column. It provide support

and free end overarm can be moved horizontally. ARBOR: It is a rod on which cutter is mounted. One end of

arbor fit into the spindle and other end is provided overarm support.

MILLING OPERATIONS

Some of the different operations that can be performed in the milling machine are,

1) SLAB OR PLAIN MILLING

2) FACE MILLING

3) SIDE MILLING

4) END MILLING

5) T-SLOT MILLING

6) ANGULAR MILLING

7) GEAR MILLING

PLAIN MILLING

It is also called surface milling or slab milling. Plain milling is use to produce flat surfaces by placing milling cutter axis parallel to surface being milled.

FACE MILLING In face milling, the cutter is used is called face milling cutter. It is a process which rotation of face milling cutter is perpendicular to the work-piece surfaces

SIDE MILLING In side milling, the cutter is used called side milling cutter. It is a process in which produce a flat surface on the side of a work piece.

END MILLING In end milling, the cutter is used is called end milling cutter. The cutter rotate on vertical to the work piece. End mill cutters have cutting teeth at one end, as well as on the sides. The edges of end mill is so weak. So, care should be taken so that the end mill touch the material slowly as possible.

T-SLOT MILLING T-slot is produced using T-slot cutter. T –slot cutter fed from one end of the work piece after the plain slot cut on the work piece using an end milling cutter. The neck portion of the cutter is passes through the already milled plain slot.

ANGULAR MILLING

In angular milling, the cutter is used called angular milling cutter. It is the process in which angular surface are produced on a work piece.

GEAR MILLING

In gear milling, gears are produced using the cutters, these cutters are called involute gear cutters. These cutters are manufactured in many sizes and shapes for different numbers of teeth per gear.

UP MILLING & DOWN MILLING

Based on the direction of the cutter and work piece feed, milling can be classified into up milling (conventional milling) and down milling (climb milling).

UP MILLING OR CONVENTIONAL MILLING

In up milling the work piece which is mounted on a table is fed in the opposite direction of the rotating cutter. That is cutter rotates against the direction in which the work is being out. Cutting force vary zero or minimum to maximum so cutting starts with minimum thickness and maximum at the end of cut. Surface finishing is poor and more power consumed in up milling while taking heavy cuts.

DOWN MILLING OR CLIMB MILLING

In down milling, cutter rotate in same direction of that in which the work is being is out. Job tool motion is same

direction in down milling. In climb milling the chip thickness varies from a maximum at the start of cut to a minimum at the end of the cut. Good surface finish obtained in down milling and less power is consumed.

REFERENCE

BASIC MECHANICAL ENGINEERING BY J.BENJAMIN BASIC MECHANICAL ENGINEERING BY RAJESH KUMAR GOOGLE -

mechanicalengineeringstudymaterial.wordpress.com

SUBMITTED TO, ARUN KAPPEN ASST.PROFESSOR MECHANICAL ENGINEERING MITS. SUBMITTED BY, ARUN C S ROLL NO: 13 COMPUTER SCIENCE MITS.