Continuous flow or on-off drain traps
Armstrong’s line of fixed lever drain traps includes two basic models available in cast iron and forged steel. The floats are light enough to handle light liquids.
With a fixed pivot, a conically shaped valve is attached to a fixed-pivot leverage system. The fixed pivot does not allow the valve to move freely to conform to the seat for tight closure. Thus, it may not seal tightly, and some loss of air or gas may be expected.
Fixed pivot operation
As the water level rises, the ball float cracks the valve to drain liquid at the same rate that it reaches the trap. (See drawings.) Changes in the rate of flow to the trap adjust the float level and the degree of opening of the valve.