In the process of conventional bending

the inner-arc side of pipe is always subjected to compress and the outer-arc side is subjected to tension during bending

as a result

non-uniform thickness of the pipe is often produced. The expanding-bending technology is an efficient way to solve this issue. However

this technology has a complex process and the forming quality might be affected by many factors. High quality titanium elbow requires high strength and uniform wall thickness. On the basis of theoretical analysis

the hot expanding-bending technology test of high strength titanium alloy was carried out. The flow law of metal in the forming process was studied. The proportional relationship between the bending deformation amount and the expansion diameter was given. Finally

the uniform thickness of 1300MPa grade elbow were obtained through the hot expanding-bending technology by means of inducing heating

and the relative wall thickness tolerance of the wall thickness was about 6%. This study is of certain guiding value for the bending process of titanium alloy.