Welding device and method for underwater friction stir welding

The invention relates to a welding device and method for underwater friction stir welding, and belongs to the technical field of underwater welding. The welding process is carried out in a water tank filled with flowing water, a water inlet is formed in one end of the water tank, a water inlet pipe is arranged at the water inlet, a water outlet is formed in the other end, a water outlet pipe is arranged at the water outlet, a welding base plate and a clamp used for fixing a to-be-welded workpiece are arranged on the inner side of the bottom of the water tank, and a hydrogen collecting device is arranged above the welding base plate and used for collecting hydrogen generated in the welding process so as to eliminate the influence of the hydrogen on a welding seam. The hydrogen collecting device is arranged above the welding base plate, so that the influence of the hydrogen on the welding seam quality is avoided, and waste gas generated in the welding process can be recycled. 本发明涉及一种用于水下搅拌摩擦焊的焊接装置及焊接方法，属于水下焊接技术