In bending, the point of contact between the face of the die block applying force against the material being bent and the circumference of the bend form. In rotary-draw and compression bending, this would be the contact between the pressure die and the bend die. In press bending, this would be the contact between the wing die and the ram die. The ray passing through this point is known as the line of tangency, despite the fact that geometrically the tangent is actually perpendicular to that ray.
FREE Tube-Bending Guide Download:
A complete guide to the principles of the 4-Step set-up for tube-bending tools
This is a printable handbook showing how to implement in four standardized steps the “forward mandrel” set-up for rotary-draw tube-bending machines and establish process control over the so-called black art. The procedure is based upon the guiding principle that the tools make the bend and takes advantage of the inserted design of modern mandrel tooling.