You are here

Draw bending of tubes

Forming where a tube is squeezed and rotated using a rotary bending die.

Illustration of Draw bending of tubes

The process

A: The workpiece, in this case a pipe held by clamps [1] to a rotary bending die [2]. Just behind the clamp enclosing the tube is a sliding pressure die [3] and a stationary wiper [4].

B: When bending the pipe is rotated along with the rotary bending die around its outline, while the follower works as a support for the forces that occur when the pipe undergoes plastic deformation. An articulated bending core [5] prevents cross section deformation.

It is not to the pipe movement but is held at its position attached to a rod through the tube aft end.

Advantages and disadvantages
In comparison with alternative methods
Perfectly contoured products
No scratches or damage to the material surface
Minimal deformation of the cross section
smaller wall thicknesses required
expensive tools