Large and small pipe welding clamp

The utility model provides a large and small pipe welding clamp, and relates to the technical field of welding clamps. The welding fixture comprises a fixed seat, a clamping block and a clamping fork, a placing groove is formed in the top of the fixed seat; the clamping block and the clamping fork are arranged on the two sides of the containing groove correspondingly and are in horizontal sliding connection with the fixing base. A sleeve groove is formed in the side, facing the clamping fork, of the clamping block and matched with the cross sections of the large and small pipes attached side by side in shape and size. In the welding process of the large and small pipes, the large and small pipes which are arranged side by side are placed into the containing groove, the clamping block and the clamping fork slide oppositely, the large and small pipes are clamped in the sleeve groove, clamping is convenient, it is guaranteed that the large and small pipes are parallel and attached side by side before welding, an