Page 46 - Module DMV20173
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3.0 SHEET METAL PROCESSES
Figure 3.16 Springback in bending.
Figure 3.17 Methods of reducing or eliminating springback in bending operations.
b. Bending radius
1. The radius at which a crack first appears at the outer fibers of a sheet being bent is
referred to as the minimum bend radius.
2. Another significant factor in radius forming is the amount, shape, and hardness of
inclusions present in the sheet metal and the amount of cold working that the edges
undergo during shearing.
3. Note that the bend radius is measured to the inner surface of the bent part.
4. Fig 3.18 (a) and (b) shows the effect of elongated inclusions (stringers) on cracking
as a function of the direction of bending with respect to the original rolling direction of
BPLK 78 DMV 20173
