Rotary draw bending machines are available in various sizes and configurations depending on your needs and budget. Unless otherwise specified all machine variations are available in a range of sizes based on tube OD from 4mm to 273mm.
A Single Stack machine can only bend one radii at a time. To bend different radii then the tooling must be removed. This configuration of machine varies from the simplest of hand operated equipment to fully automatic left or right bending equipment. The following sub sections give an overview of each.
The Unison EB1000 CNC Controlled Hand Operated Tube Bending Machine was specifically designed for prototype and small batch production. The machine has a teach mode to enable existing tubes to be removed, reproduced, and refitted in a matter of minutes. The machine is supplied with a pneumatic mandrel withdrawal lever operated from the control console, toggle clamping to both clamp and pressure die, this ensures pressure is evenly and constantly applied therefore eliminating the variation of degree of bend experienced with screw pressure die settings.
The Unison EB2000 CNC Controlled Hand & Servo Operated Tube Bending Machine is very similar to the EB1000 but has increased capabilities, allowing the customer to bend up to 50.9mm (2”) OD Tube. This has been achieved by adding a servo driven bend arm (DOB) and upgraded collet unit (POB).
The Unison Breeze Machine, has one bend head which can only bend one radii at a time. It is available in left or right bend directions. This design is the most rigid and is suited to the hardest bending applications in the aerospace and automotive industries. The bend direction is agreed with customer at time of purchase and will be determined by the part shapes they wish to make on the machine. If a different radius is required then the tooling must be removed. The machine utilised head shifting (described in the next section) to avoid colliding with the part while changing bend direction.
The Unison Breeze Left and Right Machine, has a maximum capacity of 25.4mm, one bend head which can only bend one radii at a time, but has two pressure dies which rise a fall allowing the operator to perform bends in two directions within the same part. This allows complex part shapes to be created that would collide with single direction bending machine To achieve this, the clamp can rotate 180 degrees and the bend former bend is profiled especially for this type of equipment. If a different radius is required then the tooling must be removed. This machine utilises head shifting to avoid colliding with the part while changing bend direction.
A Left and Right (Pinball) Machine, has two bend heads- each head can bend one radii at a time. To bend different radii, the tooling must be removed. Whereas a Head Shifting machine has its vertical and traverse axis on the front of the machine a and left and right machine traverses the Mandrel, DBB, and POB Units between the two heads via two synchronised traverse axes. The vertical axes at the front of the machine allow the heads to move clear while the bed traverse between them.
