Tank fitting

Claim 1

A plastic tank having side and bottom walls, a drain opening provided in said side wall adjacent said bottom wall, a circular flange having upper and lower portions portion molded integrally with the plastic tank side wall adjacent the bottom wall of said tank and concentric with the drain opening in the tank side wall, said upper portion comprising approximately 240° of the flange located within and flush with the tank side wall, said lower portion comprising approximately 100° of the flange portion extending downwardly from the tank side wall below the tank bottom wall, a plurality of circumferentially spaced apertures provided in said side wall and in said flange portion concentric with said drain opening, the apertures in the upper portion extending a circumferential distance of substantially 240° around the drain opening, the apertures in the lower portion extending a circumferential distance of substantially 120° around the drain opening, a flange and associated pipe fitting, said flange and pipe fitting having aligned openings in alignment with the drain opening, the pipe fitting flange having circumferentially spaced apertures aligned with the apertures in the tank side wall and flange portion, a bolt having an enlarged head extending through each of the aligned apertures in the upper portion of the circular flange and pipe fitting flange with the bolt heads engaging the interior surface of the tank side wall, a bolt extending through each of the aligned apertures in the lower portion of the circular flange and the pipe fitting flange exteriorly of the tank and nut assemblies secured to the free end of each bolt, whereby the necessity of including a back-up flange interiorly of the tank is precluded.