Snap Action Drain Trap - 71 Series | Armstrong | Americas

Snap Action Drain Trap – 71 Series

Snap Action Drain Trap – 71 Series

Product Specifications

Model 71-A 71-315
Maximum Capacity 1,950lb/hr (884 kg/h)  1,950lb/hr (884 kg/h)
Maximum Allowable Pressure 250 psig @ 450°F
(17 bar @ 232°C)
11,000 psig @ 100°F
(69 bar @ 38°C)
600 psig @ 750°F
(41 bar @ 400°C)
Maximum Operating Pressure 250 psig (17 barg) 1,000 psig (69 barg)
Body Material ASTM A48
Class 30 Cast Iron
Forged Steel
Connection Type Screwed Screwed,
Connection Sizes 3/4″ (20 mm)
1″ (25 mm)
3/4″ (20 mm)
1″ (25 mm)
1-1/4″ (32 mm)
1-1/2″ (40 mm)

Snap Action Drain Trap – 71 Series

Armstrong’s line of snap action, continuous flow or on-off float drain traps includes two basic models available in cast iron and forged steel. The floats are light enough to handle light liquids.

The Model 71-A is a wide-open, tight-shut drain trap for use where fine dirt and grit may be present or where liquid load is light. A flat spring in the leverage system holds the valve closed until the trap body is nearly full of water. Then it snaps open, washing dirt through. When the trap body is nearly empty, the spring snaps the valve shut.

The model 71-315 is a forged steel version of Model 71-A.

CAUTION: Ball float drain traps are not recommended where heavy oil, sludge or considerable dirt are encountered in lines. Under these circumstances, use Armstrong inverted bucket BVSW traps.


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