Chapter 23 Machining Processes Turning and Hole Making

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Chapter 23 Machining Processes: Turning and Hole Making Manufacturing Engineering and Technology , Seventh

Chapter 23 Machining Processes: Turning and Hole Making Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

MACHINING OPERATIONS PERFORMED ON A LATHE Part is rotated while being machined 1. Turning

MACHINING OPERATIONS PERFORMED ON A LATHE Part is rotated while being machined 1. Turning 2. Facing 3. Cutting with form tools 4. Boring 5. Drilling 6. Parting (cutting off) 7. Threading 8. Knurling Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 1 Miscellaneous operations that can be performed on a lathe; note that

FIGURE 23. 1 Miscellaneous operations that can be performed on a lathe; note that all parts are circular. The tools used, their shape, and the processing parameters are described throughout this chapter. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

TABLE 23. 1 General Characteristics of Machining Processes and Typical Dimensional Tolerances Manufacturing Engineering

TABLE 23. 1 General Characteristics of Machining Processes and Typical Dimensional Tolerances Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 3 (a) A turning operation, showing insert and chip removal; the machine

FIGURE 23. 3 (a) A turning operation, showing insert and chip removal; the machine tool is traveling from right to left in this photograph. (b) Schematic illustration of the basic turning operation, showing depth of cut, d; feed, f; and spindle rotational speed, N, in rev/min. The cutting speed is the surface speed of the workpiece at the tool tip. Source: (a) Courtesy of Kennametal Inc. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 4 Designations for a right-hand cutting tool, meaning that the tool travels

FIGURE 23. 4 Designations for a right-hand cutting tool, meaning that the tool travels from right to left, as shown in Fig. 23. 3 b. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 5 Forces acting on a cutting tool in turning. Fc is the

FIGURE 23. 5 Forces acting on a cutting tool in turning. Fc is the cutting force, Ft is the thrust or feed force (in the direction of feed), and Fr is the radial force that tends to push the tool away from the workpiece being machined. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

LATHES AND LATHE OPERATIONS LATHE COMPONENTS 1. Bed 2. Carriage 3. Headstock 4. Tailstock

LATHES AND LATHE OPERATIONS LATHE COMPONENTS 1. Bed 2. Carriage 3. Headstock 4. Tailstock 5. Feed rod and lead screw Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

TYPES OF LATHES 1. Bench lathes 2. Special purpose lathes 3. Automatic lathes 4.

TYPES OF LATHES 1. Bench lathes 2. Special purpose lathes 3. Automatic lathes 4. Turret lathes Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 2 General view of a typical lathe, showing various components. Source: Courtesy

FIGURE 23. 2 General view of a typical lathe, showing various components. Source: Courtesy of South Bend Lathe Co. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 10 Schematic illustration of the components of a turret lathe; note the

FIGURE 23. 10 Schematic illustration of the components of a turret lathe; note the two turrets: square and hexagonal (main turret). Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 11 (a) A computer-numerical-control lathe; note the two turrets. These machines have

FIGURE 23. 11 (a) A computer-numerical-control lathe; note the two turrets. These machines have higher power and spindle speed than other lathes in order to take advantage of new cutting tools with enhanced properties. (b) A typical turret equipped with 10 tools, some of which are powered. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 13 Examples of four parts with more complex shapes that can be

FIGURE 23. 13 Examples of four parts with more complex shapes that can be produced on a CNC lathe. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

TABLE 23. 9 Typical Production Rates for Various Machining Operations Manufacturing Engineering and Technology

TABLE 23. 9 Typical Production Rates for Various Machining Operations Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

DESIGN CONSIDERATIONS FOR TURNING OPERATIONS 1. Work piece must be easily clamped 2. Correct

DESIGN CONSIDERATIONS FOR TURNING OPERATIONS 1. Work piece must be easily clamped 2. Correct machinability of material of work piece 3. Sharp corners and major dimensional changes should be avoided 4. Blanks dimension should be as near as possible to final dimensions 5. Parts should be designed such that the cutting tool can move through the work piece without obstructions 6. Design of parts should allow the use of standard cutting tools Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

CUTTING SCREW THREADS Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven

CUTTING SCREW THREADS Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 16 (a) Cutting screw threads on a lathe with a single-point cutting

FIGURE 23. 16 (a) Cutting screw threads on a lathe with a single-point cutting tool. (b) Cutting screw threads with a single-point tool in several passes, normally utilized for large threads. The small arrows in the figures show the direction of feed, and the broken lines show the position of the cutting tool as time progresses. In radial cutting, the tool is fed directly into the workpiece. In flank cutting, the tool is fed into the piece along the right face of the thread. In incremental cutting, the tool is fed first directly into the piece at the center of the thread, then at its sides, and finally into the root. (c) A typical coated-carbide insert in the process of cutting screw threads on a round shaft. (d) Cutting internal screw threads with a carbide insert. Source: (c) Courtesy of Iscar Metals, Inc. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 17 (a) Straight chaser for cutting threads on a lathe. (b) Circular

FIGURE 23. 17 (a) Straight chaser for cutting threads on a lathe. (b) Circular chaser. (c) A solid threading die. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

BORING AND BORING MACHINES increasing the diameter of an existing hole Done either on

BORING AND BORING MACHINES increasing the diameter of an existing hole Done either on a lathe (small work piece) or on boring mills (large work pieces) Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 18 (a) Schematic illustration of a steel boring bar with a carbide

FIGURE 23. 18 (a) Schematic illustration of a steel boring bar with a carbide insert; note the passageway in the bar for cutting fluid application. (b) Schematic illustration of a boring bar with tungsten-alloy “inertia disks” sealed in the bar to counteract vibration and chatter during boring; this system is effective for boring-bar lengthto-diameter ratios of up to six. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 19 Schematic illustration of a vertical boring mill; such a machine can

FIGURE 23. 19 Schematic illustration of a vertical boring mill; such a machine can accommodate workpiece sizes as large as 2. 5 m (98 in. ) in diameter. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

DRILLING, DRILLS AND DRILLING MACHINES Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian

DRILLING, DRILLS AND DRILLING MACHINES Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 20 Two common types of drills: (a) Chisel-edge drill; the function of

FIGURE 23. 20 Two common types of drills: (a) Chisel-edge drill; the function of the pair of margins is to provide a bearing surface for the drill against walls of the hole as it penetrates into the workpiece. Drills with four margins (double-margin) are available for improved guidance and accuracy. Drills with chip-breaker features also are available. (b) Crankshaft-point drill; these drills have good centering ability, and because chips tend to break up easily, crankshaft drills are suitable for producing deep holes. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 21 Various types of drilling and reaming operations. Manufacturing Engineering and Technology

FIGURE 23. 21 Various types of drilling and reaming operations. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

DRILLING MACHINES Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R.

DRILLING MACHINES Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 25 (a) Schematic illustration of a vertical drill press. (b) A radial

FIGURE 23. 25 (a) Schematic illustration of a vertical drill press. (b) A radial drilling machine. Source: (b) Courtesy of Willis Machinery and Tools. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 26 A three-axis computer numerical-control drilling machine; the turret holds as many

FIGURE 23. 26 A three-axis computer numerical-control drilling machine; the turret holds as many as eight different tools, such as drills, taps, and reamers. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

REAMING AND REAMERS Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven

REAMING AND REAMERS Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 27 (a) Terminology for a helical reamer. (b) Inserted-blade adjustable reamer. Manufacturing

FIGURE 23. 27 (a) Terminology for a helical reamer. (b) Inserted-blade adjustable reamer. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

TAPPING AND TAPS Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven

TAPPING AND TAPS Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 23. 28 (a) Terminology for a tap. (b) Tapping of steel nuts in

FIGURE 23. 28 (a) Terminology for a tap. (b) Tapping of steel nuts in production. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.