Bending Methods for Tubing

Ram Style

• Ram style is the bending method that is most often used for electrical conduit or other light-gauge products. This method involves bracing the pipe on both the left and right of the desired bending area. Force is applied to the opposing side, between the bracing points, with a ram. This method will change the shape of the interior of the pipe into an oval. The area where the ram is applied as well as the bracing will flatten the exterior of the pipe. This method is used for controlled crush and knuckle bends with a maximum bend radius of 110 degrees.

Rotary Draw

• Rotary draw bending methods are used for pipes that will be used for handrails, ornamental iron, conduit, sand rail, chassis, roll cages and trailer frames. This method maintains the interior dimensions and shape of the pipe in addition to preserving the finish. This method involves a brace that guides the exterior of the object as it is drawn through a counter or space between a fixed, curved object. The operator moves the pipe back and forth through the counter while applying force until the desired angle is achieved. This method is used for tight radius bends with a maximum radius of 180 degrees.

Mandrel

• Mandrel bending methods are used in the manufacturing process of exhaust pipes as well as intake, process, dairy and heat exchanger tubing. This method is also used for all tubing made of stainless steel and aluminum. Mandrel bending provides a finished product with the least amount of deformity. The process involves rotary draw bending methods and setup, but it is coupled with a flexible mandrel that is placed inside the pipe directly below the desired bend to help maintain the pipe shape.

Ring Roll

• Ring roll bending methods are used to bend tubing that requires a ring or circular shape. The method can be used for the manufacturing of awnings, drums, barbecues and other large, round items. Ring roll bending involves two rollers mounted horizontally which braces the outside of the tube. An interior roller is located between the two outside rollers. The tubing is pushed through the chamber between the three rollers while pressure is placed on the interior roller with manual or hydraulic adjustments until the desired bend is achieved.