Research of CNC pipe bender forming mandrel

WANG Peng-fei; LI Dian-qi

Abstract：In CNC pipe bender, the forming process of tube wall is seen flattening , rupture, wrinkle and so on, while the design and application of mandrel could solve this difficult problem .So the optimization of the mandrel technology is very important to improve the quality of pipe bending .In this paper , it took the Taiwan Yinglin pipe bending machine ( CNC-80 Tube bender type ) as it's concerning subject , the mandrel design , structure and principle are analyzed , it discussed mandrel diameter , stretch out the amount , core numbers and their rela-tionship formulas.After that it considered how much the core pulling speed and bending speed influence ben -ding quality , as well as the fitting clearance between the mandrel and the pipe on the impacts of bending de -formation, issues of the selection and application of mandrel .It showed using mandrel could reduce the produc-tion cost, improve quality, which provide theoretical reference and practical guidance to bend forming .