Chapter 15 Metal Extrusion and Drawing Processes and

EXTRUSION a cylindrical billet is forced through a die DRAWING the cross section of

FIGURE 15. 1 Schematic illustration of the direct-extrusion process. Manufacturing Engineering and Technology ,

FIGURE 15. 2 Extrusions and examples of products made by sectioning off extrusions. Source:

FIGURE 15. 3 Types of extrusion: (a) indirect; (b) hydrostatic; and (c) lateral. Manufacturing

PROCESS VARIABLES reduction in cross sectional area die angle extrusion speed billet temperature lubrication

FIGURE 15. 4 Process variables in direct extrusion; the die angle, reduction in cross-section,

TABLE 15. 1 Typical Extrusion Temperature Ranges for Various Metals and Alloys. (See also

FIGURE 15. 7 Typical extrusion die shapes: (a) die for nonferrous metals; (b) die

FIGURE 15. 8 Extrusion of a seamless tube (a) using an internal mandrel that

FIGURE 15. 11 a extrusion. Two examples of cold extrusion; the arrows indicate the

FIGURE 15. 11 b extrusion. Two examples of cold extrusion; the arrows indicate the

IMPACT EXTRUSION Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R.

FIGURE 15. 14 Schematic illustration of the impact-extrusion process; the extruded parts are stripped

DESIGN CONSIDERATIONS 1. symmetry of cross section 2. Avoid hollow cross sections 3. Avoid

FIGURE 15. 17 Examples of poor and good design practices for extrusion; note the

FIGURE 15. 19 General view of a 9 -MN (1000 -ton) hydraulic-extrusion press. Source:

DRAWING the major processing variables are the same as extrusion: die angle, reduction in

FIGURE 15. 20 Process variables in wire drawing; the die angle, reduction in cross-sectional

FIGURE 15. 21 Examples of tube-drawing operations, with and without an internal mandrel; note

FIGURE 15. 24 Cold drawing of an extruded channel on a draw bench to

FIGURE 15. 25 An illustration of multistage wire drawing typically used to produce copper

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Chapter 15 Metal Extrusion and Drawing Processes and Equipment Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

EXTRUSION a cylindrical billet is forced through a die DRAWING the cross section of a solid rod , wire or tube is reduced or changed in shape by pulling it through a die Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 1 Schematic illustration of the direct-extrusion process. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 2 Extrusions and examples of products made by sectioning off extrusions. Source: (d) Courtesy of Plymouth Extruded Shapes. (For extruding plastics, see Section 19. 2. ) Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 3 Types of extrusion: (a) indirect; (b) hydrostatic; and (c) lateral. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

PROCESS VARIABLES reduction in cross sectional area die angle extrusion speed billet temperature lubrication Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 4 Process variables in direct extrusion; the die angle, reduction in cross-section, extrusion speed, billet temperature, and lubrication all affect the extrusion pressure. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

TABLE 15. 1 Typical Extrusion Temperature Ranges for Various Metals and Alloys. (See also TABLE 14. 3. ) Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 7 Typical extrusion die shapes: (a) die for nonferrous metals; (b) die for ferrous metals; and (c) die for a T-shaped extrusion made of hot-work die steel and used with molten glass as a lubricant. Source: (c) Courtesy of LTV Steel Company. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 8 Extrusion of a seamless tube (a) using an internal mandrel that moves independently of the ram: an alternative arrangement has the mandrel integral with the ram and (b) using a spider die (see Fig. 15. 9) to produce seamless tubing. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 11 a extrusion. Two examples of cold extrusion; the arrows indicate the direction of metal flow during Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 11 b extrusion. Two examples of cold extrusion; the arrows indicate the direction of metal flow during Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 14 Schematic illustration of the impact-extrusion process; the extruded parts are stripped by using a stripper plate. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

DESIGN CONSIDERATIONS 1. symmetry of cross section 2. Avoid hollow cross sections 3. Avoid a critical dimension in a cross-section 4. Avoid wide thin sections Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 17 Examples of poor and good design practices for extrusion; note the importance of eliminating sharp corners and keeping section thicknesses uniform. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 19 General view of a 9 -MN (1000 -ton) hydraulic-extrusion press. Source: Courtesy of Jones & Laughlin Steel Corporation. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

DRAWING the major processing variables are the same as extrusion: die angle, reduction in area, drawing speed and friction along the die-work piece interface extrusion: material is pushed through the die drawing: material is pulled through the die Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 20 Process variables in wire drawing; the die angle, reduction in cross-sectional area per pass, speed of drawing, temperature, and lubrication condition all affect the drawing force, F. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 21 Examples of tube-drawing operations, with and without an internal mandrel; note that a variety of diameters and wall thicknesses can be produced from the same initial tube stock (which has been made by other processes). Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 24 Cold drawing of an extruded channel on a draw bench to reduce its cross-section; individual lengths of straight rods or of cross-sections are drawn by this method. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.

FIGURE 15. 25 An illustration of multistage wire drawing typically used to produce copper wire for electrical wiring. Shown is a five bull block configuration; wire drawing machines can incorporate 15 or more of these drums, depending on the material and wire size. Source: After H. Auerswald. Manufacturing Engineering and Technology , Seventh Edition Serope Kalpakjian | Steven R. Schmid Copyright © 2014 by Pearson Education, Inc. All rights reserved.