مطالعه تجربي و شبيه سازي اجزاي محدود شكل دهي لوله هاي كنگره اي در فرآيند هيدروفرمينگ لوله در قالب هاي بسته و باز

Numerical and Experimental Investigation on Forming Metallic Bellows in Closed and Open-Die Hydroforming

In this paper, the possibility of forming the metallic bellows in closed-die, and also in open-die. tube hydroforming process has been studied by numerical simulation and experiment. The results obtained illustrated that forming the tube in the closed-die process is only possible for a single-convolution bellows, when the tube is fed from one end; if the feeding is performed from both the ends, then the process is also possible for a double- convolution bellow s. If the number of convolutions is more than two, then it is impossible to form the bellows in the closed-die process. But, in forming the bellows in the open-die tube hydroforming. there is no limitation on the number of convolutions.