Annular header

The utility model relates to an annular header. A header pipe is bent to be an annular shape to form an annular header, the excircle of the header is provided with drainage holes, the pitch of the drainage holes is the same with that of a membrane wall, the size of the drainage holes is the same with the inner diameter of pipes of the membrane wall, the membrane wall is cut off along an outer ring of the annular header, the pipes are aligned and welded with the drainage holes to form a whole, and a hole-opening steel plate is connected with an inner ring of the annular header. By utilizing the annular header, a form of opening a large hole with a pipe-pulling pipe-yielding mode in the past can be replaced. The annular header is simple in structure, good in standardization, low in design and manufacture cost and good in safety.