As a core load-bearing component for equipment frames, conveyor line supports and other structures, circular tube frames feature numerous joint welds and complex spatial constraints. Manual welding is prone to problems such as uneven weld beads, excessive deformation, porosity and slag inclusions. Taking aluminum alloy circular tube frames as the research object, this demonstration realizes high-precision automatic welding via industrial robots to ensure that the structural strength and dimensional accuracy of the frames steadily meet standard requirements.

The demonstration adopts a modular flexible welding platform for workpiece clamping. Quick positioning tooling is used to guarantee the coaxiality and angular accuracy of circular tube joints, providing a reliable reference for subsequent welding. Before welding, the groove surfaces and surface oxide films, oil stains and impurities of circular tubes are strictly cleaned. The groove form is optimized according to pipe diameter and wall thickness. The AC pulse MIG welding process is applied to precisely control current and voltage parameters as well as wire feeding speed, reducing heat input and lowering the risk of circular tube burn-through and collapse.

The robot adopts preset trajectory teaching and weld tracking technology to conduct multi-layer and multi-pass continuous welding on frame intersection joints and intersecting line welds. A segmented symmetrical welding strategy is adopted to balance heat input and effectively restrain frame distortion and overall deformation. The arc state is monitored in real time during the welding process to avoid arc stop defects and ensure uniform and aesthetic weld formation. Post-welding aging treatment and dimensional re-measurement are carried out, supplemented by non-destructive testing to inspect internal defects. The entire demonstration fully presents the full-process standards of circular tube frame production, including clamping and positioning, pre-welding treatment, robot welding and post-welding inspection, providing a replicable automatic welding solution for mass production.