Armstrong’s cast iron, free-floating guided lever drain traps use the same bodies, caps, lever mechanisms, valves and seats as Armstrong inverted bucket steam traps that have been proved in years of service.
Elliptical floats and high leverage make it possible to open large orifices to provide adequate capacity for drain trap size and weight.
As water begins to fill the body of the trap, the float rises, opening the discharge valve. Motion of the free-floating valve lever is guided to provide precise closure. (See drawings.) The opening of the valve is just wide enough to remove liquid as fast as it comes to the trap. Thus at times, the valve is barely cracked from the seat.
Free-floating linkage valve
A hemispherical ball-shaped valve is attached to linkage that is suspended freely on two guide pins. There is no fixed pivot, nor are there rigid guides. Therefore, the attachment is loose. There are no critical alignments, and the lever and valve may move in all directions.
Consequently, the lever may move the valve to the seat in any alignment. As the valve approaches the seat, the pressure pushes the round valve into the square edge orifice of the seat, effecting a line seal to attain bubble-tight closure. (See drawings.)