Abstract: 350 km per hour sports car interior partition USES fully enclosed design,partltion by U side Angle profiles and 25 mmaluminium profles splicing and and the top of the chassis,side walls and welded into a whole. Because o/ the precision components tobe assembled on the intermal partition wall, so the drawings require the overal! flatness ofthe internal partitlon wall after weidings3mm/2m, and the welding without any clamping fxture fixed,due to free shrinkage deformation, flatness control is more difficultHere,the above problems are solved by using auxllary tooling for rigid fxation before welding, adjusting welding sequence duringwelding, hammering welding seam after welding to eliminate internal stress and other technological measures.