Rotary draw bending without mandrel

For rotary draw bending without mandrel the tool is equipped with a catch. By rotating the tool round the bending axis the tube is inclined in the radius of the bending tool. A counter bearing (counter rollers or slide shoe) serves for absorbing transverse forces during the forming process and supports the straight tube end from outside. For bending thick-walled solid tubes a counter roller is used. Thin-walled tubes like, for example, stainless steel, copper, aluminium, etc. are bent by means of a slide shoe. By guiding the material from outside and by pressing on the slide shoe and thus the workpiece into the bending tool, possibly occurring wrinkle formation as well as expected oval distortions can be counteracted. The bending of solid material and producing repeatable pipe bends, up to a radius of 1000 mm, is possible with special bending tools.

Clear advantages of these mandrel-free bending systems are:

• quick and easy handling
• larger bending radii and higher wall thickness
• simple programming (Model 3000 + 6000)
• small, compact and maintenance-free units
• special constructions can be realised at low cost
• extremely mobile machines and precise bending results
• automatic overbend compensates thematerial typical springback