Study of circumferential welding deformation of ultra-thin ellipsoid bottom of launch vehicle
To study the welding deformation of ultra-thin ellipsoid bottom of launch vehicle,and establish a method to control the deformation,mathematical simulation and experiment were used in this paper.Results showed that:serious wave deformation was produced by the girth welding of ultra-thin ellipsoid bottom,which leaded to excessive welding misalignment and bad welding quality.The wave deformation was mainly caused by the thermal stress on the next welding zone.And wave deformation was reduced by reducing cantilevered length.Wave pitch was found to be 3.67 times of the cantilevered length when 2 mm thickness ultra-thin ellipsoid bottom was welded.Cantilevered length could be reduced by the coordination of design and process,and adding welding facility with the function of adjustment of constraint placement,which leaded to good welding stability and quality,the welding misalignment was also advanced.
ultra-thincircumferential welding of bottomwelding wave deformationmisalignment