SalahGasim Ahmed MET 103 1 MET 103 Dr. Salah Gasim Ahmed ACX F 92

SalahGasim Ahmed MET 103SalahGasim Ahmed MET 103 11

MET 103MET 103

Dr. Salah Gasim AhmedDr. Salah Gasim AhmedACX F 92ACX F 92


Drilling machinesDrilling machines


• Drilling machines, or Drilling machines, or drill pressesdrill presses, are used for:, are used for:• making holes and other operations.making holes and other operations.

• They are available in a wide variety of types and They are available in a wide variety of types and sizes. sizes.

• The most common types are:The most common types are:

1.1. Sensitive drill pressSensitive drill press

2.2. Upright drilling machinesUpright drilling machines

3.3. Multiple spindle head drilling machine:Multiple spindle head drilling machine:

4.4. The radial drilling machineThe radial drilling machine

5.5. Gang drilling machineGang drilling machine

Drilling machines, or drill Drilling machines, or drill pressespresses

Bench Mounted Bench Mounted Sensitive drill pressSensitive drill press


Floor Mounted Floor Mounted Sensitive drill pressSensitive drill press


1-Sensitive drill press1-Sensitive drill press

1.1.Bench typeBench type

1.1.Floor typeFloor type

They are designed for drilling holes They are designed for drilling holes up to ½ inchup to ½ inch

Drilling Drilling headhead

Table Table

Column Column

Base Base

press bench typepress bench type

Spindle Spindle

press floor typepress floor type


Upright drilling Upright drilling machinesmachines

Upright drilling machine is similar in Upright drilling machine is similar in design to the sensitive drill press but it design to the sensitive drill press but it has the following advantages:has the following advantages:

– It is It is larger and strongerlarger and stronger than than the sensitive typethe sensitive type

– It is used for drilling It is used for drilling large hole large hole – It has a It has a gear drive gear drive mechanism mechanism to change the spindle speedto change the spindle speed

– It may have a It may have a mechanical mechanical device to raise device to raise the work table the work table


Floor Mounted Floor Mounted Sensitive drill pressSensitive drill pressUp right drill pressUp right drill press

Drive SystemDrive System


stepped-vee pulley and stepped-vee pulley and beltbelt

variable-speed drivevariable-speed drive


The radial drilling The radial drilling machinemachine

Drilling Drilling headhead

SpindleSpindle

TableTable

Base Base

Column Column

Radial Radial armarm


The radial drilling The radial drilling machinemachine

The radial drilling machine is sometimes The radial drilling machine is sometimes called the radial arm press. It has the called the radial arm press. It has the following advantagesfollowing advantages

It is used for large workIt is used for large work Several holes can be drilled without Several holes can be drilled without

moving the work piecemoving the work piece It can accommodate various height It can accommodate various height

of workof work The machine has more power, thus The machine has more power, thus

larger cutting tool can be used.larger cutting tool can be used. On some models the drilling head On some models the drilling head

can be swiveled so that holes can be can be swiveled so that holes can be drilled at an angledrilled at an angle


Gang drilling Gang drilling machine machine

It is basically a series of single It is basically a series of single spindle drill presses mounted on a spindle drill presses mounted on a long tablelong table

It is used for mass productionIt is used for mass production

It performs different drilling It performs different drilling operations in sequenceoperations in sequence

The work is moved along the table The work is moved along the table from a station to the nextfrom a station to the next

It eliminates the need for changing It eliminates the need for changing cutting toolscutting tools


Multiple spindle head drilling Multiple spindle head drilling machinemachine

It is equipped with two or more It is equipped with two or more headsheads

Each head has several spindlesEach head has several spindles

It is used for production work It is used for production work onlyonly



Machine CapacityMachine Capacity

Machine capacity is measured byMachine capacity is measured bythe diameter of work that can bethe diameter of work that can bedrilleddrilled..


Spotting and Center DrillsSpotting and Center Drills

Spotting drills are used to position holes accurately Spotting drills are used to position holes accurately for drilling with regular drills. for drilling with regular drills.

• Lathe center drills are often used as spotting Lathe center drills are often used as spotting drills.drills.


Twist drillsA twist drill is an end cutting tool used to A twist drill is an end cutting tool used to

produce a hole in a piece of metal or other produce a hole in a piece of metal or other materialmaterial..

BodyBody Point Point ShankShank

FluteFlute ClearanceClearance MarginMargin

The main parts of a twist The main parts of a twist drilldrill

StraightStraight shank : up to ½ inch shank : up to ½ inch TaperTaper shank : more than ½ shank : more than ½ inchinch

Cutter holding Cutter holding devicedevice


For straight shank:For straight shank: Drilling chuckDrilling chuckFor Taper shank:For Taper shank: SindleSindle SleevesSleeves


Drill point Drill point angles :angles :

For general purpose drillingFor general purpose drilling

Drill point angle = 118Drill point angle = 11800

For hard materials:For hard materials:

Drill point angle = 135Drill point angle = 13500 -- 150 -- 15000

For soft materials:For soft materials:

Drill point angleDrill point angle = 90 = 9000





Measuring the size of a twist drill:Measuring the size of a twist drill:

It is a good practice to always check a drill It is a good practice to always check a drill for size before drilling a hole. Drill may be for size before drilling a hole. Drill may be checked for size by two methods:checked for size by two methods:– A drill gauge:A drill gauge:– A micrometer or vernier:A micrometer or vernier:

Always be sure that the measurement is Always be sure that the measurement is taken across the margin of the drilltaken across the margin of the drill..


Selection of the proper Selection of the proper speeds:speeds:

Factors which affect the cutting Factors which affect the cutting speed are:speed are:– Kind of work piece materialKind of work piece material– Kind of cutting tool materialKind of cutting tool material– Use of cutting fluidUse of cutting fluid– Size and type of drilling Size and type of drilling

machinemachine– Quality of finishQuality of finish


Calculation of cutting Calculation of cutting rpmrpm The required rpm can be obtained from the The required rpm can be obtained from the

equation:equation: Metric Metric Where,Where,

– CS : cutting speed (m/min), from table (1)CS : cutting speed (m/min), from table (1)– d : diameter of twist drill (mm)d : diameter of twist drill (mm)

InchInch Where,Where,

– CS : cutting speed (ft/min), from table (1)CS : cutting speed (ft/min), from table (1)– d : diameter of twist drill (in)d : diameter of twist drill (in)

d

CSx320≈

πd

CSx1000=rpm

d

CSx

d

CSxN

412


Table (1) Cutting Speeds for High Speed Table (1) Cutting Speeds for High Speed Steel DrillsSteel Drills

Material Meter/min Foot//min

Low carbon steel 0.05 – 0.3 % carbon ... 24.4 – 33.5 80 – 110

Medium carbon steel 0.3 – 0.6% carbon 21.4 – 24.4 70 – 80

High carbon steel 0.6 – 1.7% carbon …. 15.2 – 18.3 50 – 60

Steel forgings …………………………. 15.2 – 18.3 50 – 60

Alloy steel …………………………….. 15.2 – 21.4 50 – 70

Stainless steel …………………………. 9.1 – 12.2 30 – 40

Cast iron, soft gray ……………………. 30.5 – 45.7 100 – 150

Cast iron, hard chilled ………………… 21.4 – 30.5 70 – 100

Cast iron, malleable …………………… 24.4 – 27.4 80 – 90

Ordinary brass & bronze ……………… 61.0 – 91.4 200 – 300

High-tensile bronze …………………… 21.4 – 45.7 70 – 150

Monel metal …………………………... 12.2 – 15.2 40 – 50

Aluminium and its alloys ……………... 61.0 – 91.4 200 – 300

Magnesium and its alloys …………….. 76.2 – 122.0 250 – 400

Slate marble & stone ………………….. 4.6 – 7.6 15 – 25

Bakelite and similar plastics ………….. 30.5 – 45.7 100 – 150

Wood …………………………………. 91.4 – 122.0 300 – 400


Twist drill Twist drill materialsmaterials

Carbon tool steelCarbon tool steel

High speed steelHigh speed steel

Cemented carbideCemented carbide


Type of twist Type of twist drillsdrills:

General purpose drill:General purpose drill:• It suits a wide variety of materialsIt suits a wide variety of materialsLow helix drill:Low helix drill:• It is used for soft materials: It is used for soft materials: aluminium, brass, magnesium etc , for aluminium, brass, magnesium etc , for shallow holesshallow holes

High helix drill:High helix drill:• It is used for deep holesIt is used for deep holes• It is used for : aluminium, copper, die cast It is used for : aluminium, copper, die cast

materials, plasticsmaterials, plastics

Core drill:Core drill:• For drilling punched and cored holesFor drilling punched and cored holesCoolant ole drill (oil hole drill)Coolant ole drill (oil hole drill)• It has two holes from the shank to the It has two holes from the shank to the

cutting pointcutting point• It used in production machinesIt used in production machines

Straight flute drills:Straight flute drills:• for drilling brass, sheet metal work and for drilling brass, sheet metal work and

non-ferrous materialsnon-ferrous materials


Safety Safety rulesrules Wear safety glasses or gogglesWear safety glasses or goggles

Never leave the chuck key in a drill chuck at Never leave the chuck key in a drill chuck at any timeany time

Never leave the drill drift in spindleNever leave the drill drift in spindle Mount work securely, do not hold thin or small Mount work securely, do not hold thin or small

work pieces in hands while drillingwork pieces in hands while drilling Do not attempt to stop the spindle by the Do not attempt to stop the spindle by the

handshands Keep long sleeves away from spindlesKeep long sleeves away from spindles Long hair could be very dangerous when Long hair could be very dangerous when

drillingdrilling Keep work area and floor clean and free from Keep work area and floor clean and free from

oil and greaseoil and grease


Thank YouThank You

Documents

SalahGasim Ahmed MET 103 1 MET 103 Dr. Salah Gasim Ahmed ACX F 92