A Study on the Shape deviation rate of Hydroforming of Seamed tubes Based on Two Different Velocity

摘要

Due to the low price, the seamed tubes are used more and more widely in various industrial fields in recent years. The difference in material properties between the weld zone of the parent metal zone of the thin-walled seamed tubes, the deformation of the hydraulic bulging under the same conditions will also be different, thus resulting in an inconsistency in the overall bulging of the seamed tubes. In this paper, the hydraulic bulging experiment of the seamed tubes at low and medium velocity, and the shape deviation law of the seamed tubes at different velocity are obtained. In the first half of the bulging, the seamed tubes at the medium velocity drops faster than the low velocity shape deviation rate, and the medium velocity is closer to circle; in the second half of the bulging, the medium velocity is go up faster than the low velocity. The shape deviation rate is higher before the tubes are burst, but the medium velocity's radial average bulge height is smaller than the low velocity.