Lower water discharge sealed connecting element

The invention relates to a lower water discharge sealed connecting element, which comprises an insertion and connection element and a rotating cover, wherein one end of the insertion and connection element is made into a first insertion and connection end connected with a sewer pipe; the other end of the insertion and connection element is made into a second insertion and connection end; the second insertion and connection end comprises an inner layer and an outer layer; a circle of insertion and connection groove with an outward opening is formed between the inner layer and the outer layer; asealing groove is formed in the outer layer inner wall position of the upper part of the insertion and connection groove; the outer layer is provided with external screw threads; the rotating cover is provided with a middle hole; the inner wall of the rotating cover is provided with internal screw threads. The first insertion and connection end can be externally sleeved and inserted with the sewer pipe with the small dia