1-1 Kinds of Bending
1-2 Curve of Bending Force Versus Bending Angle
1-3 Air Bending and Coining
1-4 Springback
1-4-1 Why springback occurs
1-4-2 Positive and negative springback
1-5 Bottoming
1-6 Partial bending
1-7 Coining
1-8 Arrangement of Three Types of Bending

2-1 General
2-2 Reading the bending force chart
2-2-1 Explanation of symbols
2-2-2 Minimum flange length
2-2-3 Required tonnage
2-3 Four Relationships
2-3-1 Relationship between F and V
2-3-2 Relationship between F and t
2-3-3 Relationship between F and t
2-3-4 Relationship between F and b
2-4 Calculation of Bending Tonnage
2-5 Complement of the Bending Force Chart

3-1 The Necessity of General Knowledge
3-2 Requirements for Good Tooling
3-3 Tooling Materials, Heat Treatment, and Manufacturing Process
3-3-1 Hardened tooling
3-3-2 Thermally refined tooling
3-4 Length of Tooling
3-5 Sectional Shape of Tooling
3-5-1 Punches
3-5-2 Dies
3-6 Sectionalized Type
3-6-1 Sectionalized punch
3-6-2 Sectionalized die
3-7 Holder
3-7-1 Punch holder
3-7-2 Die holder
3-7-3 Die base

4-1 Process of Selecting Tooling
4-1-1 Selection of V-width
4-1-2 Tooling as a punch and die combination
4-1-3 Machine specifications and setting of tooling
4-2 Bending Pattern
4-3 V-Bending
4-3-1 90' bending tooling
4-3-2 Tooling for acute-angled bending
4-4 Radius Bend
4-4-1 Characteristics of R-bending
4-4-2 Springback in R-bending
4-4-3 Multi-breakage bending phenomenon
4-4-4 Types of R-bending
4-4-5 Summary of R-bending
4-5 Hemming
4-5-1 Type requiring tooling replacement
4-5-2 Double-deck type
4-6 Bending Sequence
4-6-1 Procedure for determining bending sequence
4-6-2 Use of tools
4-6-3 Automatic programming
4-7 Guaranteed Allowable Tonnage of Tooling

5-1 Objective of Labor Economy
5-1-1 Elimination of problem caused by spring-up
5-1-2 Reducing the number of processes
5-1-3 Increasing tooling versatility
5-1-4 Making material handling easy
5-1-5 Reducing man-hours to replace tooling
5-1-6 Bending coated workpieces
5-1-7 Elimination of welding process
5-2 Types of Labor-Saving Tooling
5-2-1 Spring-up-preventive tooling
5-2-2 Tooling that reduces number of processes
5-2-3 Versatile tooling
5-2-4 Tooling that makes material handling easy
5-2-5 Tooling that eliminates tool change
5-2-6 Tooling that produces no marring
5-2-7 Technique which eliminates welding
5-3 Points of Tooling Design
5-3-2 L-bending tooling
5-3-2 Accordion bending tooling
5-3-3 Seaming tooling
5-3-4 Urethane tooling

6-1 Dispersion of Bending Angles
6.2 Marring
6.3 Cracking
6.4 Warping

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