Disposable tank cap

The utility model relates to a disposable tank cap, which comprises a cap base, a cap body, a cap sleeve and a pulling ring positioned on the cap sleeve. The utility model is characterized in that the inner wall of the cap base is provided with an annular convex part. The cross section picture of the cap body is in the shape of reversed Chinese character tu with an upper opening and the middle part of the cap body is provided with an annular table. The cap sleeve comprises a sleeve body and a sleeve ring cap which are fixedly connected. The cross section picture of the sleeve ring cap is in the shape of reversed Chinese character tu with upper and lower openings and is also provided with a table shoulder. The pulling ring and the table shoulder are in integration and the sleeve body is composed of a cylinder body and a top ring board. The outer wall of the table shoulder of the cap sleeve is matched with the top end of the cap body. The outer wall of the annular table of the cap body and the upper end surface of the annular convex part of the cap base are matched to seal liquid. The pulling ring and the table shoulder are integrally manufactured. A gap is arranged between the lower end surface of the pulling ring and the bottom wall of the cap body. A gap is also arranged between the upper end surface of the pulling ring and the horizontal surface of the top end of the cap sleeve. The utility model has the characteristic of convenient opening and the functions of protecting the pulling ring and preventing the pulling ring from being touched.