The bolster spring seat of the railway locomotive is a waist-shaped barrel structure, which consists of two pillow-type hoarding plates and a small bolster cover plate. The small bolster cover is 30mm thick and the material is 16MnDR; the pillow-shaped hoarding plate is 16mm thick. The material is 16MnDR. With the large increase in locomotive production capacity, manual welding with low production efficiency, high labor intensity and high rework rate can not fully meet the production requirements. Therefore, robot welding is used instead of manual welding. The bolster spring seat welded joints are designed according to EN15085-railway and component welding standards. The weld between the small pillow cover and the pillow waist type is T-weld joint, the weld quality grade is CPB, and the inspection grade is CT1. 100% visual inspection, 100% surface inspection and 100% internal inspection are required. The weld between the two pillow-type coamings is a V-shaped butt joint with a weld quality of CPB and a weld inspection grade of CT1, but only 100% visual inspection and 100% surface inspection. The welding sequence is as follows: firstly, the small cover of the pillow is hung on the special rotating tool and positioned, and then the pillow waist type panel is hung, the gap is reserved, and the positioning and welding are performed. Considering the weld quality requirements and welding shrinkage, the 4HVa3 weld seam before the tack weld has a 4mm clearance, and the 16V weld has a 3mm clearance. Plenum Boxes,Duct Plenum Box,Diffuser Plenum Box,Supply Air Plenum Box Guangzhou Jointair Co., Ltd. , https://www.jointair.cn