BOTTOM OPERABLE TANK CAR VALVE ASSEMBLY WHICH DOES NOT REQUIRE A SKID

摘要

In accordance with the present invention a tank car mounting flange is welded to an opening in the tank bottom and preferably does not extend below the bottom surface of the tank more than one (I) inch to comply with AAR and DOT Regulations. A valve body including a valve seat is located concentrically within the mounting flange and is removably attached to the mounting flange. The valve body may be attached to the mounting flange with a threaded fitting, or with fasteners and a retaining ring located within the mounting flange, in which fasteners holding the retaining ring in place extend into the mounting flange. A depending housing including a lower operator is attached to the mounting flange or to the retaining ring with fasteners which define a shear plane. In order that there be sufficient material in the mounting flange to be structurally sound while including openings for the fasteners in the mounting flange, and not extend more than one (1) inch below the tank bottom, the mounting flange may include fastener portions extending into the tank above the area where the fastener openings are drilled. Further, the mounting flange fastener portion may be provided with slots or channels to facilitate lading flow into the outlet during unloading. In one embodiment the portions extending into the tank comprise mounds or knobs extending into the tank, separated by open areas for lading flow. With this arrangement neither the mounting flange and/or the valve body need extend below the lower surface of the tank bottom sufficiently far as to require a skid to comply with AAR and DOT Regulations.