This article investigates the fabrication technology of support steel structures designed for solar panels, optimized for the climatic and economic conditions of the Republic of Uzbekistan. Low-carbon St3 steel profiles with dimensions of 40x30 mm and a wall thickness of 1.7 mm were selected as the research object. To minimize thermal distortions that occur during the welding of thin-walled profiles, a custom rotating pneumatic jig-fixture was designed, and the MIG/MAG (in an argon and carbon dioxide gas mixture environment) semi-automatic welding method was optimized. The UDK-105M ultrasonic flaw detector was utilized to detect internal defects within the weld seams. The results demonstrated that the improved technological process significantly reduces production costs, enhances manufacturing productivity, and minimizes the defect rate close to zero.