Armstrong International B and BI Series Float and Thermostatic Steam Trap
High-performance condensate drainage and air venting, with a thermostatic air vent for precise pressure to temperature response from deep vacuum to 30psig.

Overview
Features
- 15 or 30psig maximum operating pressure (model dependent)
- Material construction:
- Cast iron body (ASTM A48 Class 30)
- Stainless steel internals
- Air vent: Stainless steel and bronze with phosphor bronze bellows, caged in stainless steel
- Inlet configuration:
- B Series with dual inlet connections (except 1/2in and 3/4in)
- BI Series in-line connections for sizes 1/2in, 3/4in, and 1in
- Installation orientation: horizontal installation required
Description
The Armstrong International B and BI Series Float and Thermostatic Steam Trap provides reliable condensate drainage and high air-venting capacity for heating applications. Designed for long-lasting performance and efficiency, these traps ensure continuous operation while maintaining economy. Their thermostatic air vent is engineered for a responsive reaction to the steam pressure to temperature curve, allowing for effective air removal at all operating pressures, from vacuum conditions up to 30psig.
The B Series features dual inlet connections (except for 1/2in and 3/4in sizes), providing flexible installation options. The BI Series, available in sizes 1/2in, 3/4in, and 1in, is designed with in-line connections for seamless integration into piping systems. Constructed with a durable cast iron body (ASTM A48 Class 30) and stainless steel internals, these traps offer excellent resistance to wear and corrosion.
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