Page 38 - CITS - Fitter - Trade Theory

FITTER - CITS

MODULE 2

LESSON 4 : Types of drilling machine and their specification

Objectives

At the end of this lesson you shall be able to
• identify the various types of drilling machines and its parts and functions
• state the different types of work holding devices
• state the purpose of different types of tool holding devices
• name the different types of drills and its parts, function and uses.

Definition of drilling machine: A drill machine is a tool uses for drilling hole in various material, such as a metal
ceramic wood or plastic.
Parts of drilling machine
• base.

• Column (pillar)
• work table
• spindle
• drill chuck

• hand feed level
• depth gauge adjustable
• fixed handle
• belt guard
• driving motor

Types of drill machine:
Drilling machine stationary type
• Sensitive bench drilling machine: The simplest
type of the sensitive drilling machine is shown in
the figure with its various parts marked. This is
used for light duty work. This machine is capable of
drilling holes up to 12.5 mm diameter. The drills are
fitted in the chuck or directly in the tapered hole of
the machine spindle. For normal drilling, the work-
surface is kept horizontal. If the holes are to be drilled
at an angle, the table can be tilted.

• Pillar drilling machine: This is an enlarged version
of the sensitive bench drilling machine. These drilling
machines are mounted on the floor and driven by
more powerful electric motors. They are also used for
light duty work. Pillar drilling machines are available
in different sizes. The larger machines are provided
with a rack and pinion mechanism to raise the table
for setting the work

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CITS : CG & M - Fitter - Lesson 3