Patent attributes
Manway assemblies for railroad tank cars are disclosed. In some embodiments, the manway assemblies include a cover having a perimeter portion with a plurality of spaced grooves. The manway assemblies additionally include a plurality of spaced fasteners pivotably attached to the nozzle adjacent to the opening. The manway assemblies further include an interference member attached to the cover adjacent to at least one groove. The interference member prevents pivoting of the at least one fastener from a secured position in which the fastener is received in a corresponding groove, to an unsecured position in which the fastener is spaced from the corresponding groove when the cover is in a closed position. The interference member allows pivoting of the at least one fastener from the secured position to the unsecured position when the cover is in a partially open position in which pressure contained within the railroad tank car is vented.