The B&K 521-365HN is a 1-1/4-inch x 1/2-inch black iron reducing coupling, engineered to connect two male-threaded pipes of different diameters in non-potable fluid and gas systems. As part of the ProLine Series, this coupling is built from 150-lb class malleable iron, offering exceptional strength, durability, and a secure seal in demanding industrial and mechanical applications.

This reducing coupling features female iron pipe (FIP) threaded ends that comply with ANSI/ASME B1.20.1 standards, ensuring compatibility with standard pipe threads. The black finish provides corrosion resistance in non-potable systems, while the malleable iron body allows for a tight seal due to its relative softness.

Rated for up to 500 PSI at 150°F, this coupling is ideal for use in systems transporting lubricants, oils, greases, LP gases, natural gases (e.g., nitrogen, oxygen), steam, and diesel. It is not intended for potable water applications.

Key Features:

• Material: 150-lb class malleable black iron for industrial-grade strength
• Finish: Black coating for corrosion resistance in non-potable systems
• Connection Type: 1-1/4" FIP x 1/2" FIP threaded ends
• Design: Reducing coupling for connecting pipes of different diameters
• Seal Integrity: Malleable iron provides a tight, secure seal due to its relative softness
• Thread Standard: ANSI/ASME B1.20.1 compliant
• Pressure Rating: Up to 500 PSI at 150°F
• Compliance: Meets ASTM and ASME standards
• Use Environment: Suitable for indoor and outdoor applications

Applications:

• Fuel Systems: Ideal for LP gas and natural gas distribution
• Industrial Piping: Used in systems transporting lubricants, oils, greases, and diesel
• Steam Lines: Compatible with low-pressure steam applications
• Compressed Air Systems: Provides reliable connections in pneumatic systems
• DIY & Fabrication Projects: Great for custom pipe furniture, shelving, and structural builds