High-sealing-performance expansion tank with riveted structure

The utility model provides a high leakproofness riveting structure expansion tank, relates to the rolling device technical field, including the top cover, the bottom end of top cover is equipped with the small body, the bottom end of small body is equipped with the big body, the top end periphery of big body is equipped with the second inner groove. Through the cooperation of a second inner groove formed in the periphery of the top end of the large body and a second folded edge formed in the periphery of the small body, when the small body is placed in the large body, the second folded edge can be attached to the interior of the second inner groove, through the attachment, connection is more stable, the problem of gaps is also prevented, the connection sealing performance is improved, and the service life of the large body is prolonged. Through the arrangement of the first inner groove formed in the periphery of the top end of the small body and the first convex groove fixed to the periphery of the top cover,