ABSTRACT

Gang drill

A drilling machine having a number of separately driven verticalspindles in a row, used for drilli

ng holes in a piece successively.

Gang drill is a type of drilling machine attachment accessory of drilling machine in which

various diameter of drill tool are attached in its holder or chuck and we use the various drill tools

according to our requirement. It gives angular motion to its tool which increases its versatility.

Gang drilling machines are used when several related operations such as drilling holes of

different sizes, reaming or counter boring etc. must be done on a single workpiece.

.
 TABLE OF CONTENTS

TITLE PAGE NO.

Candidates Declaration I

Abstract II

Acknowledgement III

Table Of Contents IV

CHAPTER-1 INTRODUCTION 1-8

1.1 Introduction about gang drill 1

1.2 Main Parts 2

1.3 Applications 3

1.4 Features 4

1.5 Bill Of Material 5

1.6 Specification 6

1.7 Price Description 7

1.8 Design Of Our Project 8

CHAPTER-2 WORKING OF GANG DRILL 9-10

2.1 Working 9

2.2 How A Hole Is Made 10

CHAPTER-3 DRILLING MACHINE 11-18

3.1 Drilling 11

3.2 Components Of Drilling Machine 12

3.3 Types Of Drilling Machine 14

CHAPTER-4 DRILL 19-22

4.1 Drill Material 19

4.2 Drill fixed To Spindle 20

4.3 Drill Tool Nomenclature 21

4.4 Tool Holding Devices 22

CHAPTER-5 DRILLING OPERATIONS 23-27

5.1 Classifications Of Operations 23

5.2 Drilling 23

5.3 Reaming 23

5.4 Boring 24

5.5 Counter Bore 24

5.6 counter sink 25

5.7 Tapping 26

CHAPTER-6 WORK HOLDING DEVICES 28-30

6.1 Machine Table Vice 28

6.2 Step Blocks 29

6.3 Clamps 29

CHAPTER-7 DEFINITIONS 31-32

 7.1 Definitions Used In Operation 31

7.2 Precautions For Drilling Machine 32

7.3 Safety Precautions During Operation 32

CHAPTER -8 CALCULATION FOR DESIGN 33-34

8.1 Design Of Drive Shaft 33

8.2 Design Of Spur Gear 34

REFRENCE 35

CHAPTER-1
 INTRODUCTION

GANG DRILL
1.1 Introduction:
Gang drill is a type of drilling machine attachment accessory of drilling machine in

which various diameter of drill tool are attached in its holder or chuck and we use

the various drill tools according to our requirement. It gives angular motion to its

tool which increases its versatility.

1.2 Main parts:-

1. Plates of defined thickness

2. Drill chuck

3. Drill tool

4. Bearing

5. Sleeve

6. Other component as per requirement

1.3 Application:-
1.Used for mass production,

2.Reduces the machining time to times.

3.It will reduce the time of assembly or dissembling the drill tool which decreases
the overall time of working.

4.It reduces the lead time.

5.Can drill large no. of holes in a single fee

1.4 Features:-
Manufactured as per international Quality standards

Vastly used by scaffolding manufactures

Heavy & sturdy base structure for reliable & consistent performance

Hydraulically powered feed on heavy duty LM Slides for drilling

Available in manual & automatic tube handling variants

Standard collects for drill holding

Standard straight shank H.S.S. Drills

Around 70% of the flute length can be effectively utilized

Drilling is burr free as drilling is done from opposite sides, after 180o rotation of tube

Self contained coolant system with header, flexible nozzles & collection tank with pump

PLL control & touch screen for ease of operation

1.5 BILL OF MATERIAL

 PART NAME NO. OF PARTS MATERIAL

1. Sleeve (morse taper sleeve) 1 high carbon steel

2. Gear(spur gear) 5 mild steel

3. Plate 2 mild steel

4. Handle 1 mild steel

5. Driving shaft 4 mild steel

6. Ball bearing 10 mild steel

7. Drill chuck 4 high carbon steel

1.6 SPECIFICATION:-
PARTS NAME MATERIAL USED PARTS SPECIFICATION

Sleeve high carbon steel 3-2 (OD-ID)

Driving shaft mild steel less than 0.25%carbon

Ball bearing number mild steel 6002Z -(32-14.2)(OD-ID)

Gear mild steel 60-40(T1-T2)

Drill chuck high carbon steel 1.5-13 mm , -20 UNF

UNF=UNIFIED NATION FIND

THREAD OF DRILL CHUCK=20

1.7 PRICE DESCRIPTION:-

PARTS NAME Quantity PRICE(RS)

Upper Plate 1 1000

Lower Plate 1 200

Bearing 10 500

Sleeve 1 500

Drive shaft 4 3200

Gear 5 4200

Drill chuck 4 400

handle 1 500

1.8 Design of our project:-

Constructional Details:-
Five Spur Gears

Four Driven Shaft and One Driver Shaft

Four Self centering chuck

One base Plate

One Hexagonal Plate For Holding Gear

Nine Ball Bearings

Nuts and Bolts

CHAPTER-2
 WORKING OF GANG DRILL

2.1 Working:-
The Gang Drilling Machines are offered with four drilling units fitted on common base

plate assembly. Common cast iron bench plate is made of close grained cast iron, is

provided with machined T-slots and have common coolant channel all around it. The

Gang Drilling Machine is fitted with drilling head of capacity 15mm to 32mm with

drilling head (specification same as that of general drilling machines, Stated in the

adjacent table). Drilling head, depending on the job height can be easily move upwards

and downwards with help of gears fitted in mounting shaft. This type of set up is highly

suitable for mass production of same component with multiple operations at the same

point or at same level of job face

2.2 How a hole is made:-

Under normal usage, swarf is carried up and away from the tip of the drill bit by the fluting of

the drill bit. The cutting edges produce more chips which continue the movement of the chips

outwards from the hole. This is successful until the chips pack too tightly, either because of

deeper than normal holes or insufficient backing off (removing the drill slightly or totally from

the hole while drilling

Gang Drilling with multiple chuck of different diameter But with innovation is, that

We can drill required no. of holes at any specified position by giving motion to the required

Chuck.

CHAPTER-3
 DRILLING MACHINE

3.1 Drilling:-
Drilling is the operation of producing circular hole in the work-piece by using a rotating cutter

called DRILL.

The machine used for drilling is called drilling machine.

The drilling operation can also be accomplished in lathe, in which the drill is held in

tailstock and the work is held by the chuck.

The most common drill used is the twist drill.

Drilling Machine
It is the simplest and accurate machine used in production shop.

The work piece is held stationary ie. Clamped in position and the drill rotates to make a
hole.

Types
1) Based on construction:

Portable,

Sensitive,

Radial,

up-right,

Gang,

Multi-spindle

2) Based on Feed:
Hand driven

Power driven

3.2 Components of drilling machine:-

Spindle
The spindle holds the drill or cutting tools and revolves in a fixed position in a sleeve.

Sleeve
The sleeve or quill assembly 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 work: and when its moved upward, the cutting tool is withdrawn from the work

. Feed pressure applied to the sleeve by hand or power causes the revolving drill to cut its way

into the work a fraction of an mm per revolution.

Column
The column is cylindrical in shape and built rugged and solid. The column supports the

head and the sleeve or quill assembly.

Head
The head of the drilling machine is composed of the sleeve, a spindle, an electric motor

and feed mechanism. The head is bolted 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 work or it can be swung completely out of the

way. It may be tilted up to 90 degree in either direction, to allow long pieces to be end or angle

drilled.

Base
The base of the drilling machine supports the entire machine and when bolted to the floor,

provides for vibration-free operation and best machining accuracy. The top of the base is similar

to the worktable and may be equipped with t- slot for mounting work too larger for the table.

Hand Feed

The hand- feed drilling machines are the simplest and most common type of drilling machines in

use today. These are light duty machine that are operated by the operator, using a feed handled,

so that the operator is able to feel the action of the cutting tool as it cuts through the work

piece. These drilling machines can be bench or floor mounted.

Power feed
The power feed drilling machine are usually larger and heavier than the hand feed ones they are

equipped with the ability to feed the cutting tool in to the work automatically, at preset depth of

cut per revolution of the spindle these machines are used in maintenance for medium duty work

or the work that uses large drills that require power feed larger work pieces are usually clamped

directly to the table or base using t bolts and clamps by a small work places are held in a vise. A

depth stop mechanism is located on the head, near the spindle, to aid in drilling to a precise

depth.

3.3 Types of drilling machine:-

Conventional Drilling:-

With single chuck

Conventional Drilling :-
With multiple Chuck of different Dia

Gang drilling machines are used when several related operations such as drilling holes of

different sizes, reaming or counter boring etc. must be done on a single workpiece.
Sensitive or Bench Drilling Machine:-

This type of drill machine is used for very light works. Fig.1 illustrates the sketch of

sensitive drilling machine.

The vertical column carries a swiveling table the height of which can be adjusted

according to the work piece height.

The table can also be swung to any desired position.

At the top of the column there are two pulleys connected by a belt, one pulley is mounted

on the motor shaft and other on the machine spindle.

Vertical movement to the spindle is given by the feed handle by the operator.

Operator senses the cutting action so sensitive drilling machine.

Drill holes from 1.5 to 15mm

 Sensitive Drilling Machine

Up-Right Drilling Machine:-

1. These are medium heavy duty machines.

2. It specifically differs from sensitive drill in its weight, rigidity, application of power

feed and wider range of spindle speed. Fig.2 shows the line sketch of up-right drilling

machine.

3. This machine usually has a gear driven mechanism for different spindle speed and an

4. automatic or power feed device.

5. Table can move vertically and radially.

6. Drill holes up to 50mm

Up-Right Drilling Machine

Radial Drilling Machine
It the largest and most versatile used for drilling medium to large and heavy work pieces.

Radial drilling machine belong to power feed type.

The column and radial drilling machine supports the radial arm, drill head and motor.

fig shows the line sketch of radial drilling machine.

Radial Drilling Machine

The radial arm slides up and down on the column with the help of elevating screw

provided on the side of the column, which is driven by a motor.

The drill head is mounted on the radial arm and moves on the guide ways provided the

radial arm can also be swiveled around the column.

The drill head is equipped with a separate motor to drive the spindle, which carries the

drill bit. A drill head may be moved on the arm manually or by power.
 Feed can be either manual or automatic with reversal mechanism.
CHAPTER-4
DRILL

4.1 Drill material

The two most common types are

1. HSS drill

- Low cost

2. Carbide- tipped drills

- high production and in CNC machines

Other types are

Solid Carbide drill, TiN coated drills, carbide coated masonry drills, parabolic drills, split

point
drill.
 Various types of drill

4.2 Drill fixed to the spindle:-

 Drill fixed to a spindle

4.3 Drill Tool Nomenclature:-

 Nomenclature of twist drill

4.4Tool holding devices

Below figure shows the different work holding and drill drift device. The different methods

used for holding drill in a drill spindle are

 By directly fitting in the spindle hole.
By using drill sleeve
By using drill socket
By using drill chuck

CHAPTER-5
DRILLING OPERATIONS

5.1 Classifications of operation:-

 Operations that can be performed in a drilling machine are

Drilling

Reaming

Boring

Counter boring

Countersinking

Tapping

5.2 Drilling:
It is an operation by which holes are produced in solid metal by means of revolving tool called

Drill. shows the various operations on drilling machine.

5.3 Reaming:
Reaming is accurate way of sizing and finishing the pre-existing hole.

Multi tooth cutting tool. Accuracy of 0.005mm can be achieved

5.4 Boring:
Boring is a process of enlarging an existing hole by a single point cutting tool. Boring operation

is often preferred because we can correct hole size, or alignment and can produce smooth finish.
Boring tool is held in the boring bar which has the shank. Accuracy of 0.005mm can be

achieved.

Various operations on drilling machine

5.5 Counter Bore :-

This operation uses a pilot to guide the cutting action to accommodate the heads of bolts.

illustrates the counter boring, countersunk and spot facing processes.

5.6 Countersink:-

Special angled cone shaped enlargement at the end of the hole to accommodate the
screws. Cone angles of 60, 82, 90, 100, 110, 120

Counter boring, countersunk and spot facing

5.7 Tapping:-

Tapping is the process by which internal threads are formed. It is performed either by
hand or by machine. Minor diameter of the thread is drilled and then tapping is done. show the

tapping processes.

Hand taps and tapping process using tap wrench

Various operations performed on drilling machine
 CHAPTER-6
Work Holding Devices

6.1 Machine Table Vice

The machine vice is equipped with jaws which clamps the work piece. The vice can be

bolted to the drilling table or the tail can be swung around swung around. shows the standard

and swivel vice.

The swivel vice is a machine wise that can be swivel through 360 on a horizontal plane.

Machine Table vice.

6.2 Step Blocks

These are built to allow height adjustment for mounting the drilling jobs and are used

with strap clamps and long T-slot bolts.

6.3 Clamps

These are small, portable vises , which bears against the work piece and holding devices.

Common types of clamps are C-clamp, Parallel clamp, machine strap clamp, U-clamp

etc.. shows the correct and incorrect methods of mounting the work piece.

Correct and incorrect methods of clamping the work piece.

 6.4 V-Blocks

These are designed to hold round work pieces.

6.5 Angles

Angle plates are made in a 90angle with slots and bolt holes for securing work to the

table.

6.6 Jigs

The jig guides the drill through a bushing to locate and drill holes accurately.

6.7 T- Slots Bolt

These are special bolts which has a T shaped head, which slides into the T slots of

drilling machine work table.

 CHAPTER-7
DEFINITIONS

7.1 Definitions Used In Operation:-

1. Cutting Speed (v):-

Its the peripheral speed of the drill.The cutting speed depends upon the properties of the

material being drilled, drill material, drill diameter, rate of speed, coolant used etc

v = *D*N where

D = dia of the drill in m

N = Speed of rotation in rpm

2. Feed Rate (f):-

Its the movement of drill along the axis (rpm)

3. Depth of Cut (d):-

The distance from the machined surface to the drill axis.

d=D/2

As the depth of hole increases, the chip ejection becomes more difficult and the fresh

cutting fluid is not able to cutting zone. Hence for machining the lengthy hole special type of

drill called gun drill is used.

4. Material Removal Rate:-

Its the volume of material removed by the drill per unit time

MRR = ( D2 / 4) * f * N mm3 / min

5. Machining Time (T) :-

It depends upon the length (l) of the hole to be drilled , to the Speed (N) and feed (f) of

the drill.

t = L / f N min

7.2 Precautions for Drilling machine:-

Lubrication is important to remove heat and friction.

Machines should be cleaned after use

Chips should be removed using brush.

T-slots, grooves, spindles sleeves, belts, and pulley should be cleaned.

Machines should be lightly oiled to prevent from rusting

7.3 Safety Precautions During Operation:-

Do not support the work piece by hand use work holding device.

Use brush to clean the chip

No adjustments while the machine is operating

Ensure for the cutting tools running straight before starting the operation
.
Never place tools on the drilling table

Avoid loose clothing and protect the eyes.

Ease the feed if drill breaks inside the work piece.

 CHAPTER-8
CALCULATION FOR DESIGN

8.1 Design Of Drive Shaft:-

Power (p)= 1.5 kw = 1500 w

Velocity(v) = 440m/min= 7.34 m/sec

Shaft speed(N) = 700 r.p.m.

Torque transmited by shaft:-

T = (P*60)/(2* *N)

T=(P*60)/(2* *700)

T=20.46 Nm

Torque transmitted :-

T= *d3
16

=42N/mm2

20.46*103 =8.24d3

d=13.54mm, say 16mm

d= diameter of drive shaft

 = shear stress of material

8.2 Design Of Spur Gear:-

NG = 1400 r.p.m

We know that velocity of gear

V= *DG * NG/60

7.34== *DG *1400/60

DG =0.100m

=100mm

Assume module(m)=2

We know that,

m= DP/TP

There is assume DP = Diameter of Pinion= 65mm

2= DP/TP

Tp=65/2=32.5= 35 say

TP= no of the teeth on pinion

We also know that ,

DG /Tp = TG/ TP (Velocity Ratio)

100/65= TG / 35

35*1.538= TG

TG=53.84, say 60

DG=diameter of gear
TG =teeth on the gear
NG= number of the r.p.m. of gear
 REFRENCE

1. PRODUCTION TECHNOLOGY BY P.C SHARMA

2. FOUNDRY TECHNOLOGY BY O.P KHANNA

3. WORKSHOP TECHNOLOGY BY HAZARA CHAUDHRY

4. GOOGLE.COM

5. WIKIPEDIA.ORG

6. ENCYCLOPEDIA.ORG

7. ANSWERS.COM