The minimum tool requirements for rotary draw bending are the center former bend die around which the tube is bent, and a counterbending die to hold the tube in place as it bends. Satisfactory bends are achieved using a center former and counterbend die when bending pipe or tubing with a heavy wall or a large centerline radius. When bending thin wall tube use of a mandrel and wiper die are necessary. The mandrel minimizes the amount of ovality that occurs on the tube while the wiper die eliminates wrinkles on the inside radius of the tube.
