The document summarizes the working principle and key components of a drilling machine. A drilling machine has a base that supports the entire machine and holds the column. The column supports the head assembly, which contains the spindle that holds the drill bit. The spindle revolves while the sleeve slides up and down to lower the drill bit into the workpiece or withdraw it. The head is mounted to the column, while the worktable below holds the workpiece and can be adjusted vertically and swung out of the way.

1. Drilling Operation

3. • Working Principle :-
The rotating edge of the drill exerts a large force on the work piece and
the hole is generated.
The removal of metal in a drilling operation is by shearing and extrusion

4. Boaring

7. Drilling Machine

8. • BASE - The base supports the entire machine. It should be bolted to the floor.
The top of the base is similar to a worktable and maybe equipped with T-
slots for mounting workpiece too large for the table.
• COLUMN - The column of most drill machines is circular and built rugged and
solid. The column supports the head and the sleeve or quill assembly.
• SPINDLE The spindle holds the drill (cutting tool) and revolves in a fixed
position in a sleeve. In most drilling machines, the spindle is vertical and work
is supported on a horizontal table.

9. SLEEVE (QUILL) The sleeve (quill) does not revolve but may slide in its bearing in a direction
parallel to its axis. When the sleeve carrying the spindle with a cutting tool is lowered, the
cutting tool is fed into the workpiece. When it is moved upward, the cutting tool is
withdrawn from the workpiece. Feed pressure applied to the sleeve by hand or power causes
the revolving drill to cut its way into the workpiece
HEAD The head of drill press is composed of the sleeve, spindle, electric motor and feed
mechanism. The head is connected to the column.
WORKTABLE The worktable is supported on an arm mounted to the column. The worktable
can be adjusted vertically to accommodate different heights of workpiece. It may be swung
completely out of the way.