Flat焊接flange refers to a type of flange that is connected to a vessel or pipeline using an angular weld. It belongs to the arbitrary flange category. During design, it is checked as a monolithic or loose flange based on the degree of integration between the flange ring and the straight tube section. Flange rings come in two types: with neck and without neck. Compared to neck welding flanges, flat welding flanges have a simpler structure, use less material, but are inferior in stiffness and sealing to neck welding flanges. Flat welding flanges are widely used for connecting medium and low-pressure vessels and pipelines.