presentation of drilling machine by anil dahiya sir

Anil Dahiya

Manufacturing MachinesETME-206

Assignment No .1Manufacturing Machines (4M123)Last date of submission: 22.3.2012

Q.1. (i) What is the difference between machine and machine tool? (ii) Write difference between shaper, planer & slotter. (iii)What is the difference between single purpose and special

purpose machines? (iv) What is difference between generating and forming? (v) What are major differences between CNC lathe and

conventional lathe? Q.2. (a) Explain the different cutting tool materials? Write

applications of each. (b) With neat sketch explain single point cutting tool geometry.

Q.3. (a )What do you mean by taper turning? Explain the different taper turning methods used on lathe?

(b) Explain the major work holding devices used on lathe. Q.4. (a) What is apron mechanism? Explain with neat sketch. (b) Explain the working of split or half nut.

04/07/23 19:48Anil Dahiya

Drilling Drilling machines are generally or mainly used to

originate through or blind straight cylindrical holes in solid rigid bodies and/or enlarge (coaxially) existing (premachined) holes.

Holes of different diameter ranging from about 1 mm to 40 mm

Holes of varying length depending upon the requirement and the diameter of the drill

In different materials excepting very hard or very soft materials like rubber, polythene etc.


DRILLING M/C TOOL


Machining Video


Machining Video

v operations.flv

Classification of drilling machines

1. General purpose drilling machines of common use

Table top small sensitive drilling machine

These small capacity (≤ 0.5 kW) upright (vertical) single spindle drilling machines are mounted (bolted) on rigid table and manually operated using usually small size (φ≤ 10 mm) drills.


Table top small sensitive drilling machine


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Sensitive Drill Press Parts

Hand feed leverControls down feed

pressureFeel the pressure

Manufactured in bench and floor model

Four main partsBase, column, table

and drilling head

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BaseProvides stability for machineCast iron with holes to be bolted to table or benchSlots or ribs in base allow work-holding device or

work piece to be fastened

ColumnAccurate cylindrical post that fits in baseTable may be adjusted any point (base to head)Drill press head mounted near top

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TableRound or rectangle shapedUsed to support work piece to be machinedSurface 90º to column (move around)

Drilling HeadMechanism used to revolve cutting toolSpindle: round shaft holds cutting toolQuill: houses spindle

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Sensitive Drill

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.

These low cost drilling machines have tall tubular columns and are generally used for small jobs and light drilling. 04/07/23 19:48Anil Dahiya

Pillar drilling machine


Column drilling machine

These box shaped column type drilling machines 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


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.

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. 04/07/23 19:48Anil Dahiya

Radial drilling machine


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Radial Drill

Sometimes called radial-arm drill

Advantages of this machineLarger and heavier work may be machinedDrilling head raised or loweredDrilling head moves rapidly to any desired location

while work piece remains clampedMore powerHead may swivel so holes can be drilled on angle

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Radial Drill

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Radial Drill PartsBase

Heavy, box-type, ribbed cast iron or welded steelUsed to bolt machine to floor and provide coolant

reservoirTable may be bolted to base for small work

ColumnUpright cylindrical member fitter to baseSupports radial arm at right angles

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Radial Drill PartsRadial arm

Attached to columnMay be raised and lowered by means of power-driven

elevating screwSupports drive motor and drilling head

Drilling headMounted on arm and moved along length of arm by

traverse hand wheelDrill spindle may be raised or lowered

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Radial Drill

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.

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.

2. General purpose drilling machines with more specific use.


Hand drills


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.


Turret drilling machines are structurally rigid column type but are more productive like gang drill by having a pentagon or hexagon turret.

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


Turret (type) drilling machine


In these high production machine tools a large number of drills work simultaneously on a blank through a jig specially made for the particular job.

The entire drilling head works repeatedly using the same jig for batch or lot production of a particular job.

The rotation of the drills are derived from the main spindle and the central gear through a number of planetary gears in mesh with the central gear and the corresponding flexible shafts.

Multi-spindle drilling machine


Multi-spindle drilling machineThe positions of those parallel shafts holding

the drills are adjusted depending upon the locations of the holes to be made on the job.

Each shaft possesses a telescopic part and two universal joints at its ends to allow its change in length and orientation respectively for adjustment of location of the drills of varying size and length.

In some heavy duty multispindle drilling machines, the work-table is raised to give feed motion instead of moving the heavy drilling head.


Multi-spindle drilling machine


Micro (or mini) drilling machine

This type of tiny drilling machine of height within around 200 mm is placed or clamped on a table, and operated manually for drilling small holes of around 1 to 3 mm diameter in small work pieces.

Deep hole drilling machineVery 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. It needs machines like deep hole drilling machine such as gun drilling machines with horizontal axis which are provided with

high spindle speed high rigidity tool guide 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.

PARTS OF DRILLING M/C TOOL

Column with base: it is the basic structure to hold the other parts

Drilling head: this box type structure accommodates the power drive and the speed and feed gear boxes.

Spindle: holds the drill and transmits rotation and axial translation to the tool for providing cutting motion and feed motion – both to the drill.

Drilling machines are available in varying size and configuration such as pillar drill, column drill, radial drill, micro-drill etc. but in working principle all are more or less the same. 04/07/23 19:48Anil Dahiya

Twist Drill

Classification of drill

According to type of shank they carryParallel shankTapper shank

According to type of flutes flat drill twist drill

According to length short series: 0.2mm-16mm stub series: 0.5mm-40mm long series: 1.5mm-26mm


According to application:Core drill: carry 3 parallel flutes ,used for

enlarging drilled holesDrill for long hole drilling: heavy duty drill

and larger helix angleCentre drill: Masonry drill :4mm-20mm, cutting

anle:115used for drilling centre holesAccording to the tool material:

High speed steel drillCarbide tipped drill


Parts of Twist drill

1: point: The point is the cone shaped end and it does the cutting. It consists of the following:

(A) dead centre: It is the sharp edge at the extreme tip of the drill. This should always be the exact centre of the drill.

(B) Lips: these are the cutting edges of the drill.(C) Heel : It is the portion of the point back from

the cutting edge.2: Shank :It is the portion of the drill by which it is clamped

in the spindle. The shank may be either straight or tapered. Straight shank drills are used with a chuck. Tapered shank drills have self-holding tapes that fit directly into the drill press spindle. On the taper shank is the another term is used which is called tang. This fits into a slot in the spindles sleeve.

3: Body :It is the portion between the point and the shank. The

body consists of the following parts:(A) Flutes : Two or more spiral grooves that run the length of the

drill body are called flutes. The flutes do four thing.· Help from the cutting edge of the drill point.· Curl the chip tightly for easier removal.· From channels through which chips can escape

from the hole being drilled.· Allow the coolant and lubricant to get down to

the cutting edge.(B) Margin It is the narrow strip extending back the entire length

of the flute. It is the full diameter of the drill.(C) Body Clearance:It is the part of the drill body that has been reduced in

order to cut down friction between the drill and the wall of the hole


Angles of a drill:

Rake or helix angle: angle between a plane containing the drill axis and leading edge of the land. It can have +ve, -ve or zero right hand flute have +ve, left hand flute have –ve, parallel have zero. Angle varies 0-48 (16-32 is generally used). Higher angle for softer materials and lower for harder .

Point angle (cutting angle) : angle between two opposite lips of the drill ( 80-140) ,118 for large variety of materials, smaller angle for brittle materials, larger for harder materials

Lip clearance angle: angle between flank and plane normal to drill axis (8-15) ,12 is most common

Chisel edge angle: angle formed between the cutting lip and chisel edge (120-135) greater this angle larger will be clearance.

Drill MaterialsThe two most common types are

1. HSS drill- Low cost

2. Carbide- tipped drills - high production and in CNC machines

Other types areSolid Carbide drill, TiN coated drills, carbide

coated masonry drills, parabolic drills, split point drill

Drilling And Drills

Types of drills– Twist drill: most

common drill– Step drill:

produces holes of two or more different diameters

– Core drill: used to make an existing hole bigger

Different type of drill tools


Drill fixed to the spindle

Drilling operationsDrilling operations

Drilling Centre Hole

Drilling Deep Holes

Drilling Thin Material

Drilling Pilot Hole

Drilling operations… Operations that can be performed in a drilling

machine are

Drilling Reaming Boring Counter boring Countersinking Tapping

Operations in drilling machine

Counter Boring & Counter sinking


Standard OperationsReaming

Operation of sizing and producingsmooth, round hole from previouslydrilled or bored hole

• Boring• Truing and enlarging hole by

means of single-point cutting tool

Standard OperationsSpot-Facing

Smoothing and squaring surface around hole to provide seat for head of cap screw or nut

Boring bar fitted with double-edged cuttingtoo

.

Standard OperationsTapping

Cutting internal threads in holewith cutting tool called tap

• Counterboring– Enlarging top of previously

drilled hole to given depthto provide square shoulder for head of bolt or capscrew

Operations in drilling machine

Types of cutters

Combined Countersinks and central drill :-Special drilling tool to start the hole accurately.At the end it makes countersinks in the work piece.

Gun drill :-

Machining of lengthy holes with less feed rates.

To overcome the heating and short life of the normal drill tool

Types of cuttersTapping:-

For cutting internal thread

Multi cutting edge tool.

Tapping is performed either by hand or by machine.

Minor dia of the thread is drilled and then tapping is done.

Different Type of Reamers


Mounting of job and tool in a drilling M/C

In general purpose drilling machines like column and radial arm

type, the work-piece or blank is generally mounted:

By directly clamping on the drilling machine bed particularly when the job is heavy and /or of odd shape and size.

In a vice which is clamped on the bed.

In a suitable jig clamped on the bed.


Mounting of tool & Work Piece


Step BlocksClampsV-BlocksAnglesJigsT- Slots Bolt

Work Holding Devices

Vices to hold Work pieces in Drilling


Mounting of Job in a jig which is clamped on the drill-bed


Drill socket for mounting drill chuck and taper shank drills in spindle


Drill


Drilling


Use of drilling m/c

Mainly for drilling (originating or enlarging cylindrical holes)

Occasionally for boring, counter boring, counter sinking etc.

Also for cutting internal threads in parts like nuts using suitable attachment.


DRILLING MACHINE Specifications

• Maximum drill size (diameter) that can be used

• Size and taper of the hole in the spindle

• Range of spindle speeds

• Range of feeds

• Power of the main drive

• Range of the axial travel of the spindle / bed

• Floor space occupied by the machine 04/07/23 19:48Anil Dahiya

presentation of drilling machine by anil dahiya sir

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