Types Of Drilling Machine:

 Drilling is  an  operation of making a  circular hole  by  removing a  volume of metal from the  job by cutting tool called drill. A drill  is a rotary end-cutting tool with one or more  cutting lips  and  usually one or more  flutes for the  passage of chips  and  the  admission of cutting fluid. A drilling machine is a machine tool designed for drilling holes  in metals. It is one of the  most important and   versatile machine tools  in  a  workshop. Besides drilling round  holes, many other operations can   also  be  performed on  the   drilling machine such   as  counter- boring, countersinking, honing, reaming, lapping, sanding etc


1. Portable drilling machine
2. Sensitive drilling machine
3. Upright or column drilling machine
4. Radial drilling machine
5. Gang drilling machine
6. Multi-spindle drilling machine
7. Vertical drilling machine
8. Automatic drilling machine
9. Deep hole drilling machine

Classification of drilling machines. 
(a) General purpose drilling machines of common use 
1. Table top small sensitive drilling machine 
  • These small capacity (Equal Or More Than 0.5 kW) upright (vertical) single spindle drilling
    machines are mounted (bolted) on rigid table and manually operated
    using usually small size (φ More than 10 mm) drills. Fig. typically shows one
    such machine.
Diagram Of Table top small sensitive drilling machine
Table top small sensitive drilling machine

2. Pillar drilling machine 
  • These drilling machines, usually called pillar drills, are quite similar to the
    table top drilling machines but of little larger size and higher capacity
    (0.55 – 1.1 kW) and are grouted on the floor (foundation). Here also, the
    drill-feed and the work table movement are done manually. Fig. typically shows a pillar drill. These low cost drilling machines have tall
    tubular columns and are generally used for small jobs and light drilling. 
Images Of pillar drilling machine
 Pillar drilling machine 
3. Column drilling machine 
  • These box shaped column type drilling machines as shown in Fig. are much more strong, rigid and powerful than the pillar drills. In column
    drills the feed gear box enables automatic and power feed of the rotating
    drill at different feed rates as desired. Blanks of various size and shape
    are rigidly clamped on the bed or table or in the vice fitted on that. Such
    drilling machines are most widely used and over wide range ( light to
    heavy) work. 
 Column drilling machine image
 Column drilling machine 
4. Radial drilling machine 
  • This usually large drilling machine possesses a radial arm which along
    with the drilling head can swing and move vertically up and down as can
    be seen in Fig.. The radial, vertical and swing movement of the
    drilling head enables locating the drill spindle at any point within a very
    large space required by large and odd shaped jobs. There are some
    more versatile radial drilling machines where the drill spindle can be
    additionally swivelled and / or tilted.
Radial Drilling Machine
Radial Drilling Machine
5. CNC column drilling machine
  •  In these versatile and flexibly automatic drilling machine having box column
    type rigid structure the work table movements and spindle
    rotation are programmed and accomplished by Computer Numerical
    Control (CNC). These modern sophisticated drilling machines are
    suitable for piece or batch production of precision jobs.  

(b) General purpose drilling machines with more specific use.
1. Hand drills
  • Unlike the grouted stationary drilling machines, the hand drill is a portable drilling device which is mostly held in hand and used at the locations where holes have to be drilled as shown in Fig. The small and reasonably light hand drills are run by a high speed electric motor. In fire hazardous areas the drill is often rotated by compressed air. 
image Of hand drill machine
Hand Drill
2. Gang drilling machine
  • In this almost single purpose and more productive machine a number (2 to 6) of spindles with drills (of same or different size) in a row are made to produce number of holes progressively or simultaneously through the jig. Fig. schematically shows a typical gang drilling machine.
Schematic view of a gang drilling machine
Schematic view of a gang drilling machine
3. Turret (type) drilling machine 
  • Turret drilling machines are structurally rigid column type but are more
    productive like gang drill by having a pentagon or hexagon turret as
    shown in Fig. The turret bearing a number of drills and similar
    tools is indexed and moved up and down to perform quickly the desired
    series of operations progressively. These drilling machines are available
    with varying degree of automation both fixed and flexible type. 
Turret (type) drilling machine
Schematic view of turret type drilling machine 
4. Micro (or mini) drilling machine 
  • This type of tiny drilling machine of height within around 200 mm is
    placed or clamped on a table, as shown in Fig.  and operated
    manually for drilling small holes of around 1 to 3 mm diameter in small
Photographic view of a micro (or mini) drilling machine
Photographic view of a micro (or mini) drilling machine 
5. Deep hole drilling machine
  • Very deep holes of L/D ratio 6 to even 30, required for rifle barrels, long
    spindles, oil holes in shafts, bearings, connecting rods etc, are very
    difficult to make for slenderness of the drills and difficulties in cutting fluid
    application and chip removal. Such drilling cannot be done in ordinary
    drilling machines and b ordinary drills. 
  • It needs machines like deep hole
    drilling machine such as gun drilling machines with horizontal axis which
    are provided with
  1. high spindle speed 
  2. high rigidity 
  3. tool guide 
  4. Pressurised cutting oil for effective cooling, chip removal and
    lubrication at the drill tip. 
Deep hole drilling machines are available with both hard automation and CNC system.
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