saperr.dcompletre shaper operationsocx

8/14/2019 saperr.dcompletre shaper operationsocx

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shper slotter planner

What is a shaper ?

A Machine which produces flat surfaces A Ram holding the Tool reciprocates Work is fed perpendicular to the tool working principle Cutting Tool repeatedly travels along line A B Work is fed a small distance each time Feed of work & line of tool motion are in same plane but perpendicular The tool line eventually reaches position C D

Combination of two movements results in the flat plane ABCD being machinedClassification of shapersBasic types: Horizontal Shaper Vertical Shaper Traveling head ShaperHorizontal shaper: Ram holding the cutting tool moves In horizontal planeVertical shaper: The cutting tool moves in vertical planeTraveling head shaper: Cutting tool reciprocates & movescross wise simultaneously.1. Acc. to CuttingStroke action a) Push Type Shaperb) Draw Type Shaper

a) Standard Shaper2. Acc. to theTable Design:b) Universal Shapera) Crank type3. Acc. to DrivingMechanism: b) Geared type

c) Hydraulic ShaperPush type shaper Metal is removed when the ram moves away from column

Most common type used in practice Unless otherwise specified, the term shaper refers to Push type Shaper

Draw type shaper Metal is removed when the tool is drawn towards the column Allows heavier cuts to be made Less vibration during cuttingStandard shaperWork Table can be moved
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1.Vertically & 2. HorizontallyUniversal shaperTable can be moved1. Horizontally 2. Vertically 3. Swivelled &4. TiltedThis is mostly used in Tool RoomsCrank type shaper: Driving mechanism is by crank & gearGeared type shaper: Driven by Rack & Pinion mechanism

Hydraulic shaper: Driven by oil pressure developed by a pump, which is run by an electric motor.

Construction of ShaperMain parts of a shaping machine1. BASE 5. CROSS RAIL2. COLUMN 6. SADDLE3. RAM 7. TOOL HEAD4. TABLE 8. CLAPPER BOX

1. Base Bottom most part Supports other parts of the machine Acts as a reservoir of lubricating oil Made of Cast Iron2. Column Vertically mounted on the base Houses Driving Mechanism of Ram Has guide ways on which Ram slides Made of Cast Iron3. Ram

The main moving part of a Shaper It carries Tool Head Connected to Driving Mechanism4.Table A box like casting with T-slots on its top Shaper vice is fitted in the T-slots Work is fixed in the vice5. Cross rail Used to move the Table Up & Down Upward movement is controlled by an Elevating Screw Side movement is controlled by lead screw6. Saddle It is mounted on cross rail It supports the Table Moves across the cross rail left to right Movement obtained by a cross feed screw7. Tool head It is attached to the front end of Ram Carries Clapper box & Tool post on it Can be swiveled at any angle on either side

8. Clapper box It is hinged to the tool head It houses clapper block


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Crank pin(11) is fitted in the slotted link(9) Bottom end of slotted link (rocker arm) is attached to frame of column(15) Its upper end is connected to ram(2). Electric motor drives pinion (1) Pinion (1) drives the bull gear(14) A Radial slide (16) is bolted at the centre of bull gear. Radial slide carries a sliding block(12) & a crank pin (11) As the bull gear 14 rotates, crank pin 11 rotates. So sliding block 12 also rotates on the crank pin circle. Simultaneously crankpin will move up & down in the slot of the slotted link 9.

As the crank pin11 moves, slotted link 9 gets rocking movement. This rocking movement is communicated to the ram. Thus the rotary motion of the bull gear is converted to reciprocating motion of the ram. When the link is in the position PM, ram will be at the extreme backward position. When it is at PN, ram is at extreme forward position PM&PN are tangents drawn to the crank pin circle. Forward cutting stroke takes place through the angle C1 K C2 Return stroke takes place through the angle C2 L C1 of the crank. It is evident that angle C2 K C1is greater than C2 L C1 Angular velocity of crank pin is constant. So Return stroke is completed in a shorter time. Therefore it is known as quick return motion.

Ratio between cutting time & return time. Cutting time : Return stroke = Angle C1KC2 : Angle C2LC1 Cutting time : Return time ratio usually varies bet 2 : 1. Practical limit is 3 : 2Hydraulic Quick ReturnMotion Mechanism The Ram with cutting tool has to move slowly in cutting stroke Ram to return quickly in idle stroke The first 2 methods are discussed already The 3rd method is by Hydraulic Mechanism If the Quick Return Motion is obtained by hydraulic means in a Shaper Then such a Shaping Machine is Known as HYDRAULIC SHAPER

WORKINGForward Stroke Oil is pumped to Right side of Cylinder Piston moves Left Hand Side Ram moves Forward Stroke Shaper dog hits the reversing lever Reversing lever alters valve position Oil is now pumped to Left side of Piston Piston moves Right Side
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Ram performs Return Stroke Oil on the Right side of Piston goes to reservoir At the end of Return stroke another trip dog hits reversing lever Reversing lever changes direction of stroke of Piston Thus the Cycle is repeated

QRM is obtained Due to the difference in stroke volume Volume on Left side of piston is small due to presence of piston rod Right side volume is larger ( absence of piston rod) Pump pumps same amount of oil both sides As volume is small on Left side, pressure increases Increase in pressure causes Speed of ram to increase in Return strokeAdvantages of Hydraulic Shaper Cutting tool works uniformly during cutting stroke Reverse stroke is obtained without any shock More no. of cutting speeds are obtained Good control on cutting speed Relief valve ensures safety i.e. Machine is not overloaded

Shaper Operations Machining Horizontal Surfaces Machining Vertical Surfaces Machining Angular Surfaces Cutting Slots, Grooves & Key ways Machining irregular surfaces Machining Splines / Cutting GearsSteps for Machining Work is properly held in a vice Table is raised to a gap of 25 to 30 mm between tool & work The length & position of stroke are adjusted The length of stroke should be nearly 20 mm longer than the work The approach & over run should be 10 & 5 mm respectively. Depth of cut is adjusted by rotating down the feed screw of tool head Feed is adjusted about half the width of cutting edge of tool

Machining Horizontal Surfaces Fix the work properly on the table Adjust the length of stroke Set the required cutting speed Give required feedof the table Fix an appropriate tool in the tool head Give suitable depth of cut for rough cuts Finishing the job by giving less depth of cutMachining Vertical Surfaces Fix up the job on the table firmly Align the surface to be machined properly Fix up a side cutting tool in the tool head Set the vertical slide exactly at zero Swivel the apron away from the job Switch on the machine Rotate down feed screw by hand to give down feed Feed in about 0.25 mmMachining Angular Surfaces Angular shaping is carried out to machine inclined surfaces, bevelled, dove tail etc., Set the work on the table


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Swivel the vertical slide of tool head to the required angle ( to the left or right) Set apron away from work Give down feed as per requirementCutting Rack or Splines Fix up a square nose tool in tool head Adjust the length & position of stroke Reduce the cutting speed Give suitable depth of cut Feed the work properly to get equal splinesCutting Key ways Fix up the job betweentwo centres Cut first spline similar to a key way Move / Rotate work by the required amount Use index plate for this purpose

Machining irregular surfaces Fix up a forming tool in tool post Give cross feed in conjunction with down feed Swivel the apron suitably according to the contour requiredClamping the Work on a ShaperWork should be properly & firmly fixed on the Shaper tableWork is fixed on the table by 3 methods. Using a Swivel Vice Using T bolts & Clamps Using Angle plate & C ClampsSlotting machine A Machine which produces flat surfaces A Ram holding the Tool reciprocates Ram reciprocates in verticle direction Work is fed perpendicular to the tool Slotter - working principle Cutting Tool repeatedly travels along line AB Work is fed a small distance each time

Feed of work & line of tool motion are in same plane but perpendicular The tool line eventually reaches position C D

Combination of two movements results in the flat plane ABCD being machined Work is supported on a rotary table.

Table can have longitudinal and rotary movements

Straight and rotary cuts can be produced. CLASSIFICATIONAccording to design and purpose the slottersare classified into two typesPuncher Slotter

Precision tool room SlotterPuncher slotter: Intended for removing large amount of metal from heavy works. heavy and rigid machine Ram driven by rack and spiral pinion mechanism used for machining large castings and forgingsPrecision tool room slotter: Used for tool room work, where accuracy important Lighter in construction


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Fitted with quick return mechanism Operates at high speeds and designed for light cuts Gives accurate finish Suitable for small to medium size work piecesDifference between vertical shaper and Slotter in verticle shaper the tool holding ram can tilt by about 50 with respect to verticle axis In slotter ram cannot tilt at all. In all other aspects verticle shaper and slotter are similarMain parts of a slotter1. Base 5. Cross slide2. Column 6. Saddle3. Ram 7. Tool head4. Table1. Base Bottom most part Supports other parts of the machine Acts as a reservoir of lubricating oil Made of Cast IronBase Rigidly built to take up cutting forces Top of bed is accurately finished Guide ways are provided for saddle Guide ways are perpendicular to column faceColumn Vertically mounted on the base Houses Driving Mechanism of Ram Has guide ways on which Ram slides Made of Cast Iron Also houses feeding mechanismRam Reciprocating vertically up and down of a slotter Mounted on guide ways of column

It carries Tool Head / cutting tool Connected to Driving Mechanism An arrangement is provided on the body of ram to change length of strokeTable It holds the work piece. A circular casting with T-slots on its top Movement of table can be linear or rotary Table is graduated in degrees so indexing can be done Slotter vice may be fitted in the T-slots Work may be fixed in the vice Operated manually or by powerSaddle It is mounted on guide ways of bed

It can be moved towards or away from bed Using saddle longitudinal feed is given Top is accurately finished to provide guide ways for cross slide These guide ways are perpendicular to the guide on the baseOperated either manually or by powerCross slide Circular work-table is mounted on the top. Mounted on guide ways of saddle Moves parallel to the face of the column


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Using cross slide cross feed is given Operated either manually or by power Tool head It is attached to the bottom end of Ram Carries Tool post on it Tool is fixed in position No swiveling along verticle axis or horizontal axisSpecifications of Slotting machine Max. length of Ram Stroke Diameter of work table in mm. Typeof Drive Maximum table travel. Power input Floor Space requiredSpecifications Contd.. Amount of longitudinal travel in mm No. of speeds available No. of feeds available Table feed.Slotter driving mechanism A Slotting machine produces flat surfaces The Ram holding the Tool reciprocates vertically up and down Cuts the material only in down stroke There should be some mechanism to move the ram in reciprocating motion It is called as slotter driving mechanism The mechanism commonly used is slotted disc mechanismQuick return mechanism (QRM) A Mechanism makes the ram to move slowly during cutting stroke. During return stroke ram moves at a faster rate. To reduce the idle time,It Should return quickly . The mechanism adopted isknown as QRMMethods to obtain Q.R.M. in slotter. Whitworth Q.R.M. Mechanism

2. Variable speed reversible motor drive mechanism3. Hydraulic drive MechanismThe mechanisms for QRM in slotter are similar to QRM in shaperFeed in Slotter In Slotter feed is given by table Feed movement is intermittent Feed is given at the beginning of the cutting stroke Feed may be given either manually or by power Table will have three types of feed movementsa. longitudinalb. cross andc. circular feeds.Types of feed in Slotter

Longitudinal feed: Table is fed perpendicular to the column Table moves towards or away from the columnCross feed: Table is fed parallel to the face of the columnCircular feed: table is rotated with respect to verticle axisFeed mechanism of a Slotter Uses a ratchet and pawl mechanism


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Feed shaft engaged with cross, longitudinal / rotary feed screws has the ratchet mounted on it. Ratchet is moved by small amount in one direction only with the help of a connecting rod, lever. The roller moves in the cam groove cut on the face of the bull gear of slotting machine. Operations on slotter1. Machining flat surfaces2. Machining Circular Surfaces3. Machining internal surfaces4. Machining grooves or key waysSetup for Machining Work is properly held in a vice Table is raised to a gap of 25 to 30 mm between tool & work The length & position of stroke are adjusted The length of stroke should be nearly 20 mm longer than the work The approach & over run should be 10 & 5 mm respectively. Depth of cut is adjusted by rotating down the feed screw of tool head Feed is adjusted about half the width of cutting edge of toolMachining Flat Surfaces Fix the work properly on the table Adjust the length of stroke Set the required cutting speed Give required feed of the table Tool is held in the tool head of ram Ram reciprocates up and down Feed has to be given at the beginning of cutting stroke Both internal and external surfaces can be machined Give suitable depth of cut for rough cuts Finishing the job by giving less depth of cutMachining circular surfaces Tool is set radially on the work Work piece is placed centrally on the rotary table Feed is given by the rotary table feed screw Feed screw rotates the table through an arc Adjust the length of stroke

Set the required cutting speed Finishing the job by giving less depth of cutMachining internal surfaces Fix up a tool in tool post Cross, longitudinal and rotary feed are combined Any contoured surface can be machined Mostly done manually Good skill is required from operatorMachining grooves or key ways Slotter is specially intended for cutting internal grooves External or internal gar teeth can be machined Fix up the job between twocenters Cut first a key way

Move / Rotate work by the required amount Indexing can be done by using graduations on rotary tableCutting Key ways Fix up the job between two centres Cut first spline similar to a key way Move / Rotate work by therequired amount Use index plate for this purposeWork holding devicesWork should be properly & firmly fixed on the Slotter table


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Work is fixed on the table by 3 methods.1. Using a Swivel Vice2. Using T bolts & Clamps3. Using Angle plate & C ClampsWhat is a planer ? A Machine which produces flat surfaces Consists a stationary housing for holding the tools A table holding the work reciprocates Large works, that con not be accommodate on shapers The tool is stationary but the work movesPlaner - working principle The table on which work is clamped is imparted a reciprocating movement Cutting takes place during the forward stroke of table During return stroke the cutting tool is slightly lifted Tool is fed for each forward stroke Table is driven by an electric motor Length of table stroke can be adjusted Speed of return stroke is also regulatedClassification of planersDouble housing Planer2. Open side Planer3. Pit type Planer4. Edge Planer or Plate Planer5. Divided Table PlanerDouble housing planer: It is the Standard model & most widely used Very heavy and robust Has a bed and two vertical housings are fixed Table moves along the guide ways of the bed Housing supports cross rail & tool heads. Cross rail carries two tool heads Tool head carries toolsOpen side planer

It has only one supporting column (housing) Area larger than the table can be planed Cross rail is mounted as a Cantilever Tool holders ( max.3) are mounted on Cross rail Stroke length of bed is controled by adjustable dogsPIT Planer Columns and cross rail carrying tool head move longitudinally on massive rail above the work table Bed is recessed in the floor Loading and unloading of jobs is easy Used for Planing heavy & large jobs Table and work piece resting on it are stationary and the tool reciprocatesEdge / plate planer Specially designed for squaring or beveling the edges of heavy steel plates for pressure vessels

Carriage supporting the tool is moved back and front direction Cutting can take place during both directions of carriage travel Operator stands on the platform & operates Divided table planer Also known as Tandem planer Planer has two tables on the bed Table may be reciprocated together or separatelyEach table reciprocates under different tool head For continuous production, small work pieces clamped on one table are being machined, another is


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stationary and can be used for setting up fresh works Used for quick & continuous productionMain Parts of Planing machine1. Bed2. Table3. Housing or Column4. Cross rail5. Tool heads6. Driving Mechanism7. Feed Mechanism1. Bed Large box like casting Length is nearly twice the table length Consists guide ways on which table moves Houses the driving mechanism of table Made of Cast Iron2.Table Also called Platen Large rectangular casting mounted on bed ways Holds the work & reciprocates along bed ways Top surface has T slots Work is clamped on T slots3.Housing or Column Large vertical structures on each side of the bed Supports cross rail on which tool heads are mounted Also supports the mechanism for operating the tool heads Made of Cast Iron4. Cross rail A rigid casting mounted horizontally on the column Can be moved up& down by elevating screw Carries two slides with tool heads Tool heads can be moved horizontally on the guide ways of cross rail5. Tool heads

Contains tool posts for holding the tools Tool post (clapper block) is hinged to the head During return stroke cutting tool will be lifted Tool heads can be swiveled through 60 on either side of its vertical positionSpecifications of a Planer. Distance between the two housings2. Height between Table & cross rail at its uppermostposition3. Maximum length of table travel4. Number of Speeds & feeds available5. Power input6. Floor space required7. Type of Drive

8. Net weight of the MachineMechanisms used to drive the table A Planing Machine produces flat surfaces The Table holding the Work reciprocates There should be some mechanism to move the Table in reciprocating motion, and Table to move quick during idle stroke Mechanisms to drive the Table (QRM). Open & Cross belt drive2. Reversible motor drive


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3. Hydraulic driveOpen & Cross belt drive Mechanism Used for smaller capacity machines Table is moved by gears & rack attached underthe table Counter shaft at the top of housing has 2 pulleys Pulleys transfer power to main shaft Main shaft drives the table by rack & pinion 2 Sets of fast & loose pulleys are mounted on driving shaft Smaller fast pulley is used for backward motion of table (Quick motion) It is connected by open belt drive Bigger fast pulley is driven by cross belt drive It is used to drive the table during forward stroke At the end of cutting stroke, cross belt is shifted from fast pulley to loose pulley Simultaneously open belt is shifted from loose pulley to fast pulley This is achieved by trip dog which operates belt shifting lever Thus the direction of movement is automatically reversed2. Reversible Motor Drive Mechanism Electric motor drives the bull gear through gear trains Motor is coupled to D.C. generator When motor is started, generator supplies power to reversible motor Reversible motor causes the planer table to move At the end of stroke, trip dog operates the switch which reverses the direction of table Speed of cutting stroke is reduced by regulating the field current of the generator3.Hydraulic Drive of PlanerForward Stroke of Table During cutting stroke, oil is pumped into LHS of cylinder As the area is less due to presence of piston rod, less force acts So the table moves slowly in cutting stroke At the end of each stroke trip dog operates a lever Lever actuatesthe control valve of circuitReturn Stroke of Table Oil is pumped into the Operating cylinder

Cylinder contains piston & piston rod The other end of piston rod is connected to the Table During return stroke, oil is pumped into RHS of cylinder More force acts on the piston & it moves quicklyPlaner Operations1.Planing Horizontal Surfaces2. Planing Vertical Surfaces3. Planing Angular Surfaces / Dovetails4. Planing Curved surfaces5. Planing Slots & GroovesPlaning Horizontal Surfaces Fix the work properly on the table Set the required cutting speed

Give required feed of the tool Give suitable depth of cut for rough cuts Finishing the job by giving less depth of cutPlaning Vertical Surfaces Fix the job on the table firmly Align thesurface to be machined properly Vertical slide is adjusted perpendicular to the table Swivel the apron away from the job Switch on the machine


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Rotate down feed screw by hand to give down feedPlaning Angular Surfaces Main angular planing is to make dove tails & V grooves Set the work on the table Swivel the tool head to the required angle Set apron away from work Give down feed as per requirementPlaning Formed Surfaces Fix up a square nose tool in tool head Required form is obtained by feeding the tool simultaneously in both hor. & ver. Directions Give suitable depth of cut This can also be done with the aid of a special fixturePlaning Slots & Grooves Fix up the job on the table suitably Fix Slotter tools in tool heads Givefeed using down feed screw Move the tool by the required amount to get uniform slots / groovesbroachBROACHING OPERATION A method of metal removal with a special tool called Broach. Cutting tool called broach has three types of teeth, namely roughly teeth, semi finishing teeth,finishing teeth Broach can be pulled or pushed in a fixed path Surfaces machined may be flat or contoured can be produced in a single pass or stroke of broach Both internal and external surfaces can be machined But limited to removal of 6 mm stock or lessBROACHING OPERATION Surfaces machined may be flat or contoured can be produced in a work piece by a single pass orstroke of broach. Both internal and external surfaces can be machined But limited to removal of 6mm stock or lessBROACH Tool used in broaching

Broach is a multi-teeth cutter produced to close tolerances. It has successively higher cutting edges along length It has three types of teeth, is rough, semi finish, finish teeth. Available in different shapes and sizes For irregular shapes one broach for one contour or shape has to be developed High speed steel is the most widely used material for producing broach. Carbide tools are also used for machining steel castingsCLASSIFICATION OF BROACHESBroaches may be classified on different criteria, some of them areAccording to type of operationi) internal broachii) external broachAccording to method of operation

i) push broachii) pull broachAccording to type of constructioni) solid broachii) built-up broachiii) inserted tooth broachiv) progressive cut broachAccording to functioni) surface broach


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ii) key way broachiii) round hole broachiv) Spiral broachPUSH BROACH Designed to be pushed through a stationary work piece It has tendency to bend under compressive load It is short and stocky Fewer teeth on broach Less stock can be removed for each pass So production time will be morePULL BROACH Designed to pull through a stationary work piece Tool is in tension during cutting Pull broach is long and slender It has large number of teeth More stock can be removed Production time will be lessBROACHING METHODSAccording to method of operation the broaching may be classified as pull broaching push broaching surface broaching continuous broachingPULL BROACHING Work is held stationary Broach is held in a special head Broach is pulled over or through the work Mostly used for internal broaching Surface broaching can also be donePUSH BROACHING Work is held stationary Broach is held in a special head Broach is pushed over or through the work

Mostly used fori) sizing already drilled holesii) cutting key ways Broach is operated byi) manuallyor ii) Hydraulic arbor press less metal is removedSURFACE BROACHING Work is held in a fixture and tool in tool head Either work or broach moves across each other Tools must be specially designed for each work piece Many irregular and intricate shapes can be broached Produces excellent surface finish

Time required will be very low when compared to other machining processes.CONTINUOUS BROACHING Broach tool is held stationary Work pieces are moved continuously Path of work piece movement may bei. Straight horizontalor ii. Circular Suitablefor producing similar work pieces Suitable for mass production


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Suitable for small size work pieces onlyBROACHING MACHINES Simplest of all machine tools Have less components Broaching machines consist of :work holding fixturebroaching tooldrive mechanismsuitable supporting frame Most machines are hydraulically operated Has smooth and uniform cutting action Used for low or high production quantities. CLASSIFICATION OF BROACHING MACHINESBroaching machines are mainly classified as Horizontal broaching machines (push or pull type) Vertical broaching machines Special design continuous broaching machine Rotary table continuous broaching machine horizontal continuous broaching machineHORIZONTAL BROACHING MACHINEMain parts of the broaching machine areBedHousingDrive mechanismBroach pilotFixtureBED: Bottom most part Supports other parts of the machine Made of Cast IronHOUSING: houses the driving mechanismhoues the pulling headDRIVE MECHANISM

drives the pulling headcutting stroke speed is lessreturn stroke speed is more Broach pilot holds the broach rigidly Fixture holds the work piece rigidlyHORIZONTAL BROACHING MACHINE Both surface and internal broaching can be done Broach is securely held in a pulling headIn surface broaching broach is pulled over the surface For internal broaching broach is pulled through work Mainly used for internal broaching Operated at cutting speed of 3 to 5 m/min Speed of return stroke is 30 m/min

Hydraulic drive is used for pulling head Operated at infinitely variable range of cutting speeds Hydraulic cylinder is housed on right side of the machine Long broaches are easily handled heavy work pieces are easily handled occupies more space than vertical machineUsesIt is used to machine Keyways


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Splines Slots Round holes Other internal shapesThese are further classified as Surface broaching machines internal broaching machinesVERTICAL BROACHING MACHINE it may either push type or pull type pull type is popular Main parts of vertical broaching machines areBaseColumnRam and broachFixture and tableDrive mechanism Three models are available in vertical typepull uppull downpush down Pull up model is most popular Broach is securely held inram Occupy less floor space Modern vertical machines are available with Hydraulic drive Electro-mechanical drive Hydraulic drive machines cost less Require plat form or pit for the operator Convenient to pass work from one machine to otherEmployed in multiple operations

Two rams will be provided on some machines Such machines are called duplex head machines

DUPLEX HEAD BROACHING MACHINE Machine with two heads Simultaneously two surfaces can be machined Mostly push type machines Commonly employed for surface broaching Rate of production is highCONTINUOUS BROACHING MACHINES used for mass production of small parts they are of two typesRotary continuous broaching machineHorizontal continuous broaching machine In bothmachinesBroach is stationary

Work pieces move across broachROTARY CONTINUOUS BROACHING MACHINES Work pieces are loaded on the table Table rotates continuously During broaching broach is stationary Work pieces are held in fixtures Work pieces come into contact with broach during table rotation Loading and unloading done on the table It is a surface machining operation


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Heavy production rate

Chain carries work holding fixtures Work pieces are placed in fixtures

Broach is held stationary When chain rotates the work pieces move against stationary broach It is a surface broaching operation Heavy production rateSPECIFICATION OF BROACHING MACHINE Main specificationLength of stroke in mm.Force that can be applied to broach in tonesi.e., broaching machine with specification 1000-10 means Machine has 1000 mm stroke length and 10 tones broach driving forceOther parameters to be specified are Broaching speed

Return speed Machine horse power Floor space required H.P of the motorBROACHING OPERATIONSBroaching is applied for various internal and external surfaces round and irregular shaped holes of 6 to 100 mmdiameter Flat and contoured surfacesMost operations are completed with one pass of the broachIn all broaching operations Work is held in a fixture Tool is held in tool head (pulling or pushing head) Either work or tool move across each other Various broaching operations are as shown in following slidesNomenclature of broach toothPitch:linear distance between cutting edge of one tooth and corresponding edge on next toothLand:top portion of toolground to provide a slight clearanceBack off:it is the clearance angle of broachits value vary from 0.50 to 200Rake angle:it corresponds to rake angle of lathe tool

its value increases as ductility increasesADVANTAGES OF BROACHING rate of production is high Less skilled worker can be employed High accuracy can be obtained High surface finish can be obtained Rough and finish cut both are completed in one pass both internal and external surfaces can be machined Any form that can be reproduced on broach can be machined


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Cutting fluid may be readily applied

Life of broach tool is high Cutting temperature and tool wear is low Cutting force acts in clamping direction Process can be semi or fully automisedLIMITATIONS OF BROACHING

High tool cost Economical only for mass production Sharpening is difficult and expensive Not suitable for very large work pieces Surfaces should not have obstructions Cannot remove large amount of stock Very light and delicate jobs cannot be broached

Planer

Planer

Types of planers-description of double housing planer-specifications-principles of operation-drives-

quick return mechanism-feed mechanism- work holding devices and special fixtures-types of tools-

various operation.

What is planer?

A planer is a type of metalworking machine tool that is analogous to a shaper, but larger, and with the

entire workpiece moving beneath the cutter, instead of the cutter moving above a stationary

workpiece. The work table is moved back and forth on the bed beneath the cutting head either by

mechanical means, such as a rack and pinion gear, or by a hydraulic cylinder.

Planer

Planing is used for large workpieces too big for shapers Planing machines have largely been replaced by planing mills In planing, large workpieces and their support tables are slowly moved against the tool head.


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Shaper:

Shaper

Types of shapes-specifications-standard-plain-universal-principles of operations-drives-quick return

mechanism-crank and slotted link-feed mechanism-work holding devices-Special fixture-various

operations.

Shaper:

A shaperis a machine tool used for shaping or surfacing metal and other material.

Shapers have been largely superseded by milling machines or grinding machines in modern industrial

practice. The basic function of a shaper machine is still sound and tooling for them is minimal and very

cheap to reproduce. They can be invaluable for jobbing or repair shops where only one or a few pieces


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are required to be produced and the alternative methods are cost or tooling intensive. The

mechanically operated machines are simple and robust in construction, making their repair and

upkeep easily achievable.

A shaper operates by moving a hardened cutting tool backwards and forwards across the workpiece.

On the return stroke of the ram the tool is lifted clear of the workpiece, reducing the cutting action to

one direction only.

The workpiece mounts on a rigid, box shaped table in front of the machine. The height of the table can

be adjusted to suit this workpiece, and the table can traverse sideways underneath the reciprocating

tool which is mounted on the ram, the table motion is usually under the control of an automatic feed

mechanism which acts on the feedscrew. The ram slides back and forth above the work, at the front

end of the ram is a vertical tool-slide that may be adjusted to either side of the vertical plane. This

tool-slide holds the clapper box and toolpost from where the tool can be positioned to cut the straight,

flat surface on the top of the workpiece. The tool-slide permits feeding the tool downwards to put on a

cut it or may be set away from the vertical plane, as required.

The ram is adjustable for stroke and, due to the geometry of the linkage, it moves faster on the return

(non-cutting) stroke than on the forward, cutting stroke. This action is via a slotted link or whitworth

link.

Cutting fluid may be employed to improve the finish and prolong the tool's life.


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Slotter

Types of slotters-specifications-method of operation-Whitworth quick return mechanism-feed

mechanism-work holding devices-types of tools

Work Holding DeviceSome work holding devices:

"M" Qwik-Change Face Plate

"M" System Vise Fixturing

"Tom Thumb" Flexible Cable Arm 6" or 9""Tom Thumb" Flexible Indicator Holder

?C? Clamps

2-Way Cross Slide Machine Vise

3 Jaw Set-Tru Fine Adjustment Lathe Chucks

3" Pipe Vise

4 Pc. Die Holder Set

4" Cross Slide Vise

52 Piece Clamping Kit

5C Collet Block Set

5C Collets

5C Expanding Collet Kit

5C External Oversize Collet - Steel or Aluminum

5C Spin Index

6" Milling Machine Vise with Swivel Base

90 Holder

Accurate Accessories Monorail Indicator Holder

Adjustable Trolleys


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saperr.dcompletre shaper operationsocx

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