Page 333 - 04. Subyek Engineering Materials - Manufacturing, Engineering and Technology SI 6th Edition - Serope Kalpakjian, Stephen Schmid (2009)

Forming and

Shaping Processes

and Equipment

We generally tend to take for granted many of the products that we use today and
the materials and components from which they are made. However, when we in-
spect these products, we soon realize that a wide variety of materials and processes
has been used in making them (Fig. HI.1). Note also that some products consist of a
few parts (mechanical pencils, light bulbs), while others consist of thousands of
parts (automobiles, computers) or even millions of parts (airplanes, ships). Some
products have simple shapes with smooth curvatures (ball bearings, bicycle han-
dles), but others have complex configurations (engine blocks, pumps) and detailed
surface features (coins, silverware). Some products are used in critical applications
(elevator cables, turbine blades), whereas others are used in routine applications
(paper clips, forks, knives). Some products are very thin (aluminum foil, plastic
film), whereas others are very thick (ship hulls, boiler plates).
Note that the words forming and shaping are both used in the title of this part
of the book. Although there are not always clear distinctions between the two terms,
“forming” generally indicates changing the shape of an existing solid body. Thus, in

Shaped windshield Molded dashboard
Forged valves /- Drawn tube for antenna
Powder-metal filters Cold-rolled
Ceramic spark plug sheet metal or
reinforced plastic
Blow-molded
for body
windshield-
washer
Stamped
tank
Stamped _ license plates
Wheel COVGVS Injection-rnolded
Deepgrawn on pan tail light lenses
- Fuel tank
Compression-molded tires Springs

FIGURE lll.l Formed and shaped parts in a typical automobile.

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