For 0.5-in.-thick plate, it shows an inside bend radius of either 0.781 in. However, a bend allowance chart I have from our press brake manufacturer gives different information. Then I’d multiply this answer by the material thickness: 0.75 × 0.5 = 0.375 in. Is this the property to which you refer? Using the median of 20 percent and material thickness of 0.5 in., would this equate to × 0.5 = 0.75.
So in this case, the minimum inside bend radius is 2 times the material thickness.” If I am looking at properties for A36 steel, I see elongation properties between 18 and 21 percent. If the material is 0.5 inch thick: 4 × 0.5 = 2. Now, multiply that answer by the plate thickness. Next, subtract 1 from that answer: 5 – 1 = 4. To state your example, “If the steel has a tensile reduction value of 10 percent, divide 50 by that value: 50/10 = 5. You described a rough rule to find a steel’s minimum bend radius: Divide 50 by the material’s reduction percentage, as specified by the material supplier, subtract by 1, and then multiply by the plate thickness.
Q: In a previous Bending Basics article, you mention a “material’s tensile reduction percentage” used for calculating the minimum inside bend radius of various metals. Grain, increases the required minimum inside radius of Longitudinal bending, or bending with the material
