The invention is a rotary draw bending machine and process for bending
materials such as tubes or pipes into precise bends. A spindle holds a
bending die, and a radial arm holds a counter-die. The spindle and arm
are simultaneously rotated in opposite directions by a dual hydraulic
drive controlled by an electro-hydraulic control system with foot pedal
controls. The bend angle is preset by a protractor-like dial and limit
switch mechanism. The radial arm has a slide track to align the
counter-die with the bending die. The ratchet mechanism has teeth to
allow incremental advancement of the counter-die when aligning it with
its bending die to accurately set the gap between the dies. The machine
is used with a wide variety of dies to bend a wide variety of workpiece
diameters. The ratchet mechanism preferably includes a fine tuning device
to provide an infinite range of alignment positions.