Patent attributes
The present disclosure provides a method for air bending a plate of material such as steel which is characterised by having two bending steps, wherein the bending punch in the second bending step has a smaller radius and/or the die width used in the second bending step is smaller than the die width used in the first bending step. The method of the disclosure can achieve a significant improvement in the bendability of materials, particularly high strength steels. The disclosure also provides new bending apparatus that are specifically adapted to carrying out the method of the disclosure, including a nested double die having a second narrower die residing below and within the first die, and an adjustable die having a height adjustment means (either in the support, bending punch or both) capable of accommodating movement of the material during the adjustment to form the second die width.
