Thickness distribution of a hydroformed Y-shape tube

The process of hydroforming a Y-shape tube was investigated through numerical simulation and experiments. Characteristics of three different forming stages were studied. Thickness distribution of these three stages and the thickness of typical location that varies with internal pressure during forming process were analyzed when the calibration pressure was 136 MPa. It is shown that thickness distribution of the leftward fillet transition region is the thickest, rightward takes the second place, the top of the protrusion is the thinnest after forming. The influence of different calibration pressures on the thickness distribution was studied through numerical simulation. It is indicated from the simulation results that with the increase of calibration pressure, the biggest thickening rate is not obviously changed; however, the highest thinning rate increased significantly.