The Research On The Forming Technology Of Large-sized Diameter Welded Pipe

Welded pipe forming process is a complex process which belongs to elastic-plastic large deformation and contact non-linear coupling process.Its theory is far behind actual production practice.Welded pipe forming technics and roller design are based on experience formulation,technics and rollers design's validity should be checked by production practice is its main disadvantage,for the cost is very high and is not suitable for market economy.Large dimension and high strength pipe which is not capable to be produced by existing continuous rolling forming and cage roll forming technics is the future of welded pipe.Study of welded pipe's whole forming process is important to change the design model from lying on experience to design based on numerical design,also,developing a mixed forming technics depends on the study of the whole forming process.In this paper the virtual rollers'design is based on the figure of the profile.(?)30×3 mm,(?)219×7mm and (?)610×16mm welded whole forming process is simulated using ANSYS/LS-DYNA;calculated and analysed the forming process from initial state to the last;obtained transformation diagram of stress&strain for the steel plate in the forming process. The method based on numerical simulation provides the basis for the rational designing of the roller profile of the forming rollers of the welding pipe mill.