Roles of Surface Booster System on Bending of Thin-Walled Copper Tube

Thin-walled C12200 circular copper tube has been widely used in HVAC (heating, ventilation, air conditioning, and refrigeration) industry. Rotary draw bending is a versatile and precise method in forming of thin-walled copper tubes. Wall thinning and sectional fattening are the two main defects that affect tube quality in industrial applications. With traditional die settings, such as adjusting position or type of the mandrel, one factor usually decreases at the expense of increasing the other. An assistant equipment, surface booster system, has been recently developed to relieve both defects at the same time. In the present study, the role of the booster system in the bending process is investigated with finite element simulation. A basic model of copper tube rotary draw bending is established and validated by experiments. Then, cases of different sets of main parameters of the booster system are studied. The relationship between loading force, lower displacement, speed of the booster, and forming characteristics of tube is obtained based on which suggestions about process parameters settings are given. The results provide a better understanding of the role of the booster system in the improvement of forming quality.