M.P- II-UNIT III-SHAPER, MILLING AND BROACHING MACHINES.ppt
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This document provides information on shaper, milling, and broaching machines. It describes the main parts and specifications of a shaper machine and discusses different types of shapers. It also covers the various parts, specifications, classifications, and operations of milling machines. Finally, it briefly introduces broaching machines.
M.P- II-UNIT III-SHAPER, MILLING AND BROACHING MACHINES.ppt
- 1. UNIT -3 SHAPER, MILLING AND BROACHING MACHINES
- 2. SHAPER Shaping is a process of machining a flat surface which may be horizontal, vertical, inclined, concave or convex using a reciprocating single point tool. A shaping machine is a reciprocating type of machine tool.
- 3. SHAPER
- 4. . • .
- 5. Main parts of a shaping machine • Base • Column • Cross rail • Saddle • Table • Ram • Tool head
- 6. SHAPER SPECIFICATION • Maximum length of stroke • Maximum crosswise movement of the table • Maximum vertical adjustment of the table • Type of driving mechanism • Power of the motor • Available speed and feed • Type of shaper-plain or universal • Floor space required • Total weight of the shaper • Ratio of cutting stroke time and return stroke time
- 7. Types of shaping machine • A. According to the type of driving mechanism 1. Crank type 2. Hydraulic type 3. Geared type • B. According to the design of the table 1. Plain shaper 2. Heavy duty shaper 3. Standard shaper 4. Universal shaper • C. According to the position and travel of ram 1. Horizontal shaper 2. Vertical shaper • D. According to the type of cutting stroke 1. Push cut shaper 2. Draw cut shaper
- 8. OTHER SHAPERS Crank type shaper Crank and slotted link mechanism of a crank type shaper converts the rotation of an electric motor into reciprocating movement of the ram. Though the lengths of both the forward and return strokes are equal, the ram travels at a faster speed during return stroke. This quick return is incorporated in almost all types of shaper. Hydraulic shaper The ram of a hydraulic shaper is connected to a piston. Oil at high pressure is pumped to the cylinder of the hydraulic system. As the oil pushes the piston, the ram reciprocates. Hydraulic shapers are high power machines and are used for heavy duty work. Universal shaper The universal shaper has a special type of table which can be swiveled and positioned at any angle about a horizontal axis. Apart from the cross and vertical travel, the table of a universal shaper can be swiveled to any angle to machine inclined surfaces. In the process, the position of the work in the table need not be changed. These machines are utilized in precision workshops
- 9. QUICK RETURN MECHANISMS 1. Hydraulic drive 2. Crank and slotted link mechanism 3. Whitworth mechanism
- 10. Hydraulic drive
- 11. Crank and slotted link mechanism
- 14. FEED MECHANISM • Hand feed • Automatic table feed
- 15. Hand Feed
- 16. Automatic table feed - Paul and Ratchet Mechanism
- 17. Work Holding Devices – in SHAPER
- 18. Method of Clamping • Clamp in a vise • Clamp on the table • Clamping on V- Block • Clamp on Angle Plate • Fixture
- 19. Clamp in a vise
- 20. Clamp on the table
- 21. Clamping on V- Block
- 22. Clamp on Angle Plate
- 23. Fixture • To improve the machining accuracy , a fixture is designed with T-Bolt, V-Blocks and clamps for holding the work. • So the total production and cost is reduced
- 24. TYPES OF TOOL • According to shape – straight tool , cranked tool Goose necked tool • According to direction of cutting Left hand Right hand • According to the finishing required Roughing tool Finishing tool
- 25. . • According to type of operation– Down cutting tool Parting off Tool Squaring tool Side recessing tool • According to the shape of cutting edge Round Nose tool Square nose tool
- 26. SHAPING OPERATIONS 1. Machining Horizontal surface 2. Machining Vertical surface 3. Machining Angular surface 4. Machining Slots , Grooves and Keyways surface 5. Machining Irregular surface
- 30. Machining Slots , Grooves and Keyways surface
- 32. MILLING
- 33. PRINCIPLE It’s a process of removing metal by feeding the work piece against the rotating multi point cutter
- 34. SPECIFICATION 1. Length and width of table 2. Max. longitudinal cross and vertical travel of the table 3. Number of spindle speeds and feeds 4. Power of driving motor 5. Floor space and net weight 6. Spindle nose and taper size 7. Type of milling machine
- 35. CLASSIFICATION OF MILLING MACHINE The milling machines are classified according to the general design of the machine. 1. Column and knee type a) Plain milling machine b) Universal milling machine c) Omniversal milling machine d) Vertical milling machine 2. Table type milling machine 3. Planer type milling machine 4. Special type milling machine
- 36. HORIZONTAL MILLING MACHINE • Its one type of column and knee type milling machine
- 39. VERTICAL MILLING MACHINE • Its one type of column and knee type milling machine Mostly vertical milling machine used to perform end milling and face milling operations
- 43. UNIVERSAL MILLING MACHINE • The basic difference between a universal horizontal milling machine and a plain horizontal milling machine is the addition of a table swivel housing between the table and the saddle of the universal machine. • This permits the table to swing up to 45° in either direction for angular and helical milling operations. The universal machine can be fitted with various attachments such as the indexing fixture, rotary table, slotting and rack cutting attachments, and various special fixtures
- 44. Possible motions in Universal milling machine • Vertical movement through the knee • Cross movement through the saddle • Longitudinal movement of the table • Angular movement of the table by swiveling the table on the swivel base
- 45. Omniversal milling machine • This is a modified form of a horizontal milling machine. • It provided with two spindles, one of which is in the horizontal plane while the other is carried by a universal swiveling head
- 46. Bed type milling machine
- 47. Duplex head fixed bed type milling machine
- 49. Drum type miller
- 51. Peripheral milling The machining is performed by the cutting edges on the periphery of the milling cutter. It is classified under two headings 1. Up milling 2. Down milling
- 52. WORK HOLDING DEVICES MILLING • T – bolt and clamps • Angle plates • V-Blocks • Machine vice • Milling Fixture • Dividing heads
- 55. 3. Indexing Head • Its used for dividing the work piece periphery at the work pieces into any number of equal divisions. The process of dividing the periphery of work is called indexing. • Indexing is essential for cutting gears, splines, equally spaced grooves, hexagonal heads etc.
- 56. Tool Holding Devices 1. Arbors 2. Adaptors 3. collets
- 57. 1.Arbor Spacing collars are used to set the cutter in the required position
- 58. Stub arbor Its similar to previous method , but smaller in size
- 59. 2.Adaptor If the size of the cutter shank is smaller than the hole of the spindle nose, adaptors are used to hold the cutter
- 60. 3.Collet
- 61. Milling cutters 1. Plain milling cutter 2. Side milling cutter 3. End milling cutter 4. Angle milling cutter 5. T-slot milling cutter 6. Slitting saws 7. Form milling cutter 8.Fly cutters 9. Woodruff key slot milling cutter
- 63. . Side milling cutter
- 67. Slitting saw milling cutter .
- 69. 8.Fly cutters
- 70. Woodruff key slot milling cutter
- 71. Milling Operations • Plain or slab milling • Face milling • Angular milling • Straddle milling • Gang milling • Form milling • End milling • T-slot milling • Gear milling
- 72. Plain or slab milling • It is the operation of production of a flat surface parallel to the axis of rotation of the cutter. It is also called as slab milling. Plain milling cutters and slab milling cutters are used to perform this operation.
- 73. Face milling Operation where the front teeth of the tool are in engagement to make a flat surface.
- 74. Angular milling • Production of an angular surface on a workpiece other than at right angles to the axis of the milling machine spindle is known as angular milling. Example of angular milling is the production of the ‘V’ blocks
- 75. Straddle milling • It is the operation of production of two vertical surfaces on both sides of the work by two side milling cutters mounted on the same arbor. By using suitable spacing collars, the distance between the two cutters is adjusted correctly. • The straddle milling is commonly used to produce square or hexagonal surfaces.
- 76. Gang milling • It is the operation of machining several surfaces of work simultaneously by feeding the table against a number of cutters (either of same type or of different type) mounted on the arbor of the machine. • This method saves much of machining time and mostly used in production work.
- 77. Form milling • The form milling is the operation of production of irregular contours by using form cutters. • Machining convex and concave surfaces and gear cutting are some examples of form milling.
- 78. End milling • It is the operation of producing a flat surface which may be vertical, horizontal or at an angle to the table surface. • The end milling is performed by a cutter known as an end mill. • End milling is mostly performed in a vertical milling machine.
- 79. T- slot milling • Its done on work piece in two stages • First using end milling a plain slot is made • Then in second stage T-slot cutter is used to enlarge the slot as shown in fig
- 80. Gear cutting • Gear cutting operation is performed in a milling machine by using a form cutter. • The work is held between centers on a universal dividing head. • A proper gear cutter is selected and the teeth is produced on w/p
- 81. INDEXING OR DIVIDING HEADS 1. Plain or simple dividing head 2. Universal dividing head 3. Optical dividing head
- 82. Plain or simple dividing head • The index plate having 12 or 24 slots equally spaced on the periphery. • The spindle is directly connected to handle. • The job is held between the centers • The hand lever is used for locking the spindle in position.
- 83. Universal dividing head • Worm gear mechanism is connected to main spindle. • Worm is mounted on the shaft. • The worm gear has 40 teeth and the worm is single threaded. • So 40 turns of crank will move the spindle by one complete revolution. • A spring loaded pin of the crank fits into the holes in the index plate. If the pin moved from one hole to the next in a 24 hole circle of the index plate , the spindle will revolve by 1/40 x 1/24 = 1/960 of a turn.
- 84. .
- 85. INDEXING METHOD 1. Direct or rapid indexing 2. Plain or simple indexing 3. Differential indexing 4. Compound indexing 5. Angular indexing
- 86. DRILLING
- 87. DRILLING Drilling is the process of producing hole on the work piece by using a rotating cutter called drill. Drilling may be done in a lathe or vertical milling machine. It can conveniently be done, quickly and at low cost in a drilling machine. Drilling machine can also used for boring, counter-boring, counter-sinking, reaming, tapping and spot facing operations. Drilling machines are used in machine assembly, repair shop, tool room, maintenance work, agricultural machinery etc.
- 88. Types of drilling machine 1. Portable drilling machine (or) Hand drilling machine 2. Sensitive drilling machine (or) Bench drilling machine 3. Upright drilling machine 4. Radial drilling machine 5. Gang drilling machine 6. Multiple spindle drilling machine 7. Deep hole drilling machine
- 89. SPECIFICATIONS OF DRILLING MACHINE Weight of the machine. Power of the machine in HP. Max. spindle travel is in mm. Max. size of the drill in mm. Table size of max. dimensions of a job can mount on a table. The No. of spindle speed in rpm. The No. of automatic spindle feeds mm/rev. Floor space required.
- 90. Portable drilling machine • It can be carried and used anywhere in the workshop. It is used for drilling holes on work pieces in any position, which is not possible in a standard drilling machine. • These machines can accommodate drills from 12mm to 18 mm diameter.
- 91. Sensitive drilling machine (or) Bench drilling machine • The drill is fed into the work purely by hand . The operator can sense the progress of the drill into the work because of hand feed. The machine is named so because of this reason. • It can handle drills upto 15.5mm of diameter
- 93. Upright drilling machine Though it looks like a sensitive drilling machine, it is larger and heavier than a sensitive drilling machine. Holes of diameter upto 50mm can be made with this type of machine
- 95. Radial drilling machine The radial drilling machine is intended for drilling on medium to large and heavy work pieces. It has a heavy round column mounted on a large base. The column supports a radial arm, which can be raised or lowered to enable the table to accommodate work pieces of different heights.
- 97. Gang drilling machine • Gang drilling machine has a long common table and a base. Four to six drill heads are placed side by side. The drill heads have separate driving motors. This machine is used for production work. A series of operations like drilling, reaming, counter boring and tapping may be performed on the work by simply shifting the work from one position to the other on the work table. Each spindle is set with different tools for different operations.
- 99. Multiple spindle drilling machine This machine is used for drilling a number of holes in a work piece simultaneously and for reproducing the same pattern of holes in a number of identical pieces.
- 100. 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.
- 101. Feed mechanism
- 102. Drilling operations • . (a) Reaming (b) Taping (c) Counter-boring (d) Countersinking (e) Center drilling (f) Spot facing
- 103. Drilling operations . Producing larger hole on the previous drilled hole upto 50mm dia Enlarging the hole using single point cutting tool Enlarging hole somewhere at its end
- 104. .
- 105. Nomenclature
- 106. Mounting the drill tool 1. Fitting directly in the spindle 2. By using sleeve 3. By using socket 4. By means of chuck
- 107. Fitting directly in the spindle • The drill is directly held in the spindle by friction. • To remove the drill from spindle, a tapered wedge called drift is forced into the slotted hole in the spindle
- 108. By using a sleeve If the shank of drill smaller than the taper in the spindle hole, a sleeve is used. The sleeve with drill is fitted in the hole of the spindle
- 109. By using a socket • Its used when taper shank of the drill is larger than taper hole of the spindle • The body of the socket has taper hole which is larger than the drill spindle bore • So the bigger drill can be fitted into the socket
- 110. By using chucks • Its suitable for holding any smaller size drills, straight shank drills and other tools not having taper at the holding end. • Drill chucks have tapered shanks which fit into the machine spindle. • The jaws used to hold the drills
- 111. BORING MACHINES
- 112. Introduction • One of the most versatile machine tools; used to bore holes in large and heavy parts as engine frames, machine housings etc which are practically impossible to hold and rotate in an engine lathe or in a drilling machine. • Also drilling, milling and facing can be preformed with equal facility. • Along with attachments screw cutting, turning, grinding or gear cutting can also be performed.
- 113. SPECIFICATIONS OF BORING MACHINE • Type of machine-floor, planer type, or multi spindle etc. • Max. size of boring spindle diameter in mm. • Max. spindle travel in horizontal and vertical direction in mm. • Max. travel of table in longitudinal and cross-wise directions in mm. • Range and number of spindle speeds in rpm. • Range and number of spindle speeds in mm/rev. • Floor-space required for the machine in m. • Weight of machine in Tonnes. • H.P of the machine motors.
- 114. Types of boring machine 1. Horizontal boring machine a. Table type b. Floor type c. Planer type d. Multiple head type 2. Vertical Boring Machine a. Vertical boring mill b. Vertical turret lathe boring machine 3. Precision Boring Machine 4. Jig Boring Machine
- 115. Types 1. Horizontal boring machine: • The work is supported on a table which is stationary and tool revolves in a horizontal axis. • Can perform boring, reaming, turning, threading, facing, milling , grooving and many other operations with suitable tools. • Work piece which are heavier and asymmetrical can be easily held and machined. • Different types has been designed to suit the different purpose.
- 118. Floor type – Horizontal boring machine
- 119. Planer type – horizontal boring machine
- 120. Multi spindle– horizontal boring machine
- 121. Types 2. Vertical Boring Machine: • The work rotates on a horizontal table about a vertical axis and the tool is stationary except for feed. • Machine may look like a vertical lathe. • Larger diameter and heavy work pieces, can be set up more quickly than in lathe. • Multiple tooling may be adapted with its turret type tool post, increasing the rate of production.
- 126. Vertical Turret lathe boring Machine
- 127. Precision Boring Machine • It uses a single point cutting tools to machine surfaces rapidly and accurately. • Cemented carbide and diamond tipped tools are operated at a very high cutting speed to produce accurately sized holes with fine surface. • Jig boring machine is a precision boring machine, resembles to vertical milling machine in construction. • Accurate positioning of holes is achieved by Lead screw method or Mechanical / Electrical Gauging method or Optical measuring method.
- 128. Precision Boring Machine Jig Boring Machine
- 129. Broaching
- 130. Introduction • Broaching is the process of removing metal with a tool which has “teeth” arranged in a row. Each tooth is successively higher than the previous tooth and removes more material. In broaching, one stroke or cycle of the machine produces a finished part. • Broaching is used to produce both internal and external features. Production rates are high and tolerances of +/- .0005” are possible.
- 131. SPECIFICATION • Max. length of stroke in mm. • Type of drive: Electro-Mechanical or Hydraulic drive. • Power range. • Speed and Feed. • Weight of the machine. • Floor space.
- 132. Broaching machine
- 133. Broach
- 134. TYPES OF BROACHES 1. According to types of tool movement (a) Horizontal type (b) Vertical type (c) Continuous type 2.According to the types of operation (a) Push type (b) Pull type 3. According to the types of surface to be broached (a) Internal type (b) External type 4. According to the construction of broach (a) Solid type (b) Progressive cut type 5. According to the operation to be performed on the work piece (a) Surface broach (b) Round hole broach (c) Keyway broach (d) Spline broach (e)Burnishing broach
- 135. Broaching methods Pull Broaching Workpiece is clamped to the broaching machine in stationary position and the broach is pulled through the work. Broaches are usually long and are held in a special head. Pull broaching is mostly used for internal broaching. Push Broaching Workpiece is held in the broaching machine in stationary position and broach is pushed through the portion of workpiece to the machined. Normally push broaching is done by hand and arbor presses (hydraulic press). This method is also recommended for internal broaching like for sizing and finishing the holes, cavities, and key ways. Surface Broaching Any one of two, either workpiece or the broach (tool) is kept moving and other is kept stationary. The method is widely used as surface finishing operation. In case of surface broaching, the broaching tool is specifically designed for the shape to be finished. Continuous Broaching In continuous broaching the broach is held stationary in the broaching machine and workpiece is moved continuously. The teeth of movement of the workpiece may be either straight, horizontal or circular. This is generally used for broaching a large number of similar workpieces at a time.
- 136. Operation
- 137. Horizontal type internal broaching machine
- 138. Horizontal type surface broaching machine
- 139. Vertical broaching machine - push down type
- 140. Vertical broaching machine - pull down type
- 142. Rotary table continuous Broaching Machine
- 144. Nomenclature Pull End ---- Pull end is made to attach the broach to the broaching machine through the puller head. Front Pilot -- This centres the broach in the hole to be finished just before start of processing. Roughing Teeth --These are the cutting edges which remove larger amount of stocks during cutting. Larger amount removal generates poor quality of surface finish but makes the operation faster. Finishing Teeth --- These are cutting edges removing smaller stocks of material. These are used for final finishing of the surfaces and their accurate sizing. Rear Pilot and Follower Rest --This is a supporting device to the broach when it is likely to complete its operation of broaching. Land --It is the width of flank face of the broach normally it is kept slightly inclined to give relief angle to the flank face of broach. Pitch -- It is the distance between two corresponding points on two successive teeth of a broach. Normally pitch of finishing teeth of a broach is kept comparatively smaller than the rough cutting teeth. Height of the Teeth ---Height of the roughing and finishing teeth gradually increases from the shank to the finishing teeth. This increment is called the cut per tooth, it depends on the material being machined. Normally the cut per tooth is taken from 0.01 or 0.2 mm for the finishing teeth and it may go up 0.2 mm for the cutting teeth.
- 145. Parts produced in broaching
- 146. • Advantages and Limitations of Broaching Major advantages • Very high production rate (much higher than milling, planning, boring etc.) • High dimensional and form accuracy and surface finish of theproduct • Roughing and finishing in single stroke of the same cutter • Needs only one motion (cutting), so design, construction,operation and control are simpler • Extremely suitable and economic for mass production Limitations • Only through holes and surfaces can be machined • Usable only for light cuts, i.e. low chip load and unhard materials • Cutting speed cannot be high • Defects or damages in the broach (cutting edges) severelyaffect product quality • Design, manufacture and restoration of the broaches are difficultand expensive • Economic only when the production volume is large.
- 147. Disadvantages (a) Its initial cost is quite high. (b) Very large sized work pieces can not be subjected to broaching operation. (c) Broaching is not possible for the surfaces having obstructions. (d) Removal of larger stocks is not possible in broaching operation. (e) Clamping devices require frequent maintenance and cost.
- 148. THE END