Combination top operable and bottom operable tank lading valve assembly

Abstract

A tank vehicle lading valve assembly is provided including a lading valve mounted in an opening in the bottom of the tank which is movable vertically between open and closed positions. A valve housing or outlet chamber including an unloading spout is attached below a tank bottom mounting flange with fasteners, which preferably define a shear plane. A first operator attached to an upper portion of the lading valve extends vertically up through the tank to the upper portion of the tank where it is adapted to receive a suitable handle or tool to move the lading valve between open and closed positions. A second operator is preferably attached to a lower portion of the lading valve. The second operator portion preferably extends at least partially through the valve housing. Thus the lading valve is operable from either the top of the tank or from the bottom of the tank. The first operator may be eliminated and the lading valve operated from the bottom. Preferably in the event of impact to the valve housing, the housing will shear off or drop off along the plane defined by the fasteners extending into the mounting flanges, and the lower second operator portion will shear off or drop off from the second operator, leaving the lading valve in place to substantially prevent escape of lading from the tank.