1. The thickening of the intrados of a tube while under the force of the bend forming process. If a compressive force exceeds the elastic limit of the tubing material, the tube will wrinkle or buckle.
2. The effect created by captive lip and heart-shaped cavities of slight flattening of the tube towards the plane of bend at the line of tangency.
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.