Forged carbon steel for vertical and horizontal installation
For pressures to 1,000 psig (69 bar) . . .
Capacities to 1,300 lb/hr (590 kg/hr)
Armstrong Model 411G vertical installation and Model 421 horizontal installation offer smaller capacities at higher pressures.
A unique leverage system multiplies the force
provided by the bucket to open the valve against system pressure. The
mechanism is free-floating and has no fixed pivots to create wear or
Because the mechanism is located at the top of
the trap, no dirt can collect on the orifice. Small particles of dirt
are held in suspension until discharged by the full differential purging
action when the bucket sinks, pulling the valve off the seat.
The discharge orifice is surrounded by a water
seal, which prevents live steam loss. Automatic air venting is provided
by a small vent hole in the bucket.
Inverted bucket traps drain continuously,
although discharging intermittently, allowing no condensate backup. They
are also resistant to water hammer.
Model 421 adds the convenience
and savings of in-line repairability and is designed to meet today’s
energy-management requirements efficiently and economically over a long,
trouble-free service life.
- Armstrong Steam Trap Inverted Bucket Service Guide – Installation and Maintenance (PDF)
- Pressure Change Assembly – Installation and Maintenance (PDF)
- “Series 300, 400, 411-G, 5000 & 6000 Inverted Bucket Steam Traps” – Installation and Maintenance (PDF)
- “Series 880A, 980, 421 & EM Inverted Bucket Steam Traps” – Installation and Maintenance (PDF)
Submittal Drawing (5 items)