Abstract: With the rapid development of steel bridge construction, the demand for efficient manufacturing processes for steel bridges is becoming increasingly urgent. In the manufacturing of steel bridge I-beams, the conventional single-wire submerged arc welding（SAW） process has problems such as multiple construction processes, high consumption of welding materials, low production efficiency, Therefore, it is necessary to improve and optimize the single-wire SAW process. Through welding process experiments, the feasibility of the double-wire SAW process without groove and root cleaning for 20mm thick T-joints has been verified, the performance of the welded joints meets the relevant specifications. The double-wire SAW process without groove and root cleaning has been successfully applied in production, significantly improving the welding efficiency of I-shaped steel beam and achieving the desired results.