Image Number 3 for United States Patent #4905728.
A swing check valve where the opposite end portions of the hinge pin of the disc are held in hinge pin recesses by an annular wall in the valve body. The wall in the valve body is sufficiently sized that the valve disc can swing through the wall through an arc of substantially 90.degree. between in its open and closed positions. The wall may be formed as a part of the valve body or as a separate retainer ring secured in the valve.