Abstract: Objective Aiming at the problems such as surface cracks and internal porosity that are prone to occur in the circumferential laser welding of the front volute-shielding structural component of the thermal control system, this study investigates the influence of laser welding prarameters on the welding quality of the structural component, in order to clarify the appropriate range of welding parameters and improve the stability of welding quality. Methods By using simulation calculations and experimental characterization, the main evaluation indicators are the transverse residual stress of the joints, formation quality of the welds, weld penetration depth and internal porosity, the study investigates the influence of key factors such as joint form, laser power, welding speed, defocus amount, and shielding gas on the formation and internal quality of the welded joints. Results The results show that the welding protrusions can improve the formation quality of the welds and significantly reduce the transverse residual stress of the welds. The weld penetration depth increases with the increase of laser power. The perpendicularity of structural components is positively correlated with laser power. The porosity inside the weld increases with the increase of welding speed within the range of 0.3 m/min to 1.0 m/min, but the overall porosity is still maintained at a low level. When the defocus amount is positive and exceeds a specific value, the welding mode changes from deep penetration welding to thermal conductivity welding, and the porosity of the joint is gradually reduced. The use of N₂ as shielding gas and tail blowing can provide a stable air pressure environment, thereby reducing weld defects. Conclusion By taking reasonable laser welding technological measures, a appropriate range of welding parameters can be obtained, effectively controlling the formation and internal quality of the welded joints, thereby ensuring the sealing performance of the welded joints, the perpendicularity of the structural components after welding and other properties. This provides a reference example for the design of laser welded joints for similar products.