Pipe and Tube Bending Pipe
bending machines are typically human powered, pneumatic powered, hydraulic assisted, or electric servo motor. In the pipe bending operation the tube may be supported internally or externally to preserve the cross section of the pipe.
In operations where there is flexibility in the shape of the pipe, the pipe does not need to be supported, however there will be some deformation in the both the cross section of the overall pipe and the wall thickness in different areas of the bend.
Tube bending as a process starts with loading a tube into a pipe bender and clamping it into place between two dies, the clamping block and the forming die. The tube is also loosely held by two other dies, the wiper die and the pressure die. After that has been completed the fitter will start the bender, while the tube is pulled around the forming die creating an elbow, U-bend, 2-D or 3-D bent tubes. A three dimensional tube is a tube with each opening on different planes. A two dimensional tube is a tube with each opening on the same plane.
Types of Bending Processes and Equipment Used
Pipe bending techniques are varied and offer different advantages and disadvantages depending on the function of the bend and the type of material being bent.
Some use mechanical force and some use heat treatment, the most common are as follows:
Press Bending
Rotary Draw Bending
Mandrel bending
3 Roll Bending
Bending springs
Heat induction bending
Sand packing/hot-slab bending