Movably combined crane tower section welding fixture with attachment device and product

The invention discloses a movably combined crane tower section welding fixture with an attachment device and an attachment section product machined by the welding fixture. The welding fixture comprises a frame base, an end plate, a vertical column, a square flange support, a round flange support, a butting support, a locking device and a joint clamp die, wherein the end plate, the vertical column, the square flange support and the round flange support are arranged on the frame base, the butting support is arranged at the upper end of the vertical column, and the locking device and the joint clamp die are arranged on the end plate. According to the structural characteristic of an attachment section that four triangular main chord die blocks are pairwise symmetrically and movably connected into a rectangle, the triangular main chord die blocks of the attachment section are pairwise symmetrically welded, assemblies are ensured to be precisely positioned when being assembled, positioned and welded on the fixture, welding deformation of workpieces is decreased, and correction time for overall deformation of the workpieces before and after welding of the assemblies is shortened. The attachment section welding fixture is easy for ensuring workpiece interchangeability, reducing labor intensity and improving labor productivity.