1-1/2 inch Black Iron Coupling Female x Female

1-1/2 inch Black Malleable Iron Coupling – Threaded Fitting for Gas and Water Systems

The 1-1/2 inch Black Iron Coupling is a straight, internally threaded fitting used to join two male-threaded pipe sections of equal diameter. Fabricated from black malleable iron, it is suitable for low- to medium-pressure systems including natural gas, propane, air, steam, and water distribution.

Engineered for mechanical strength and consistent thread engagement, this coupling is an essential component in industrial, commercial, and residential systems where reliability under variable pressure and temperature conditions is required.

Performance Attributes

• ✅ Malleable Iron Construction Manufactured from ASTM A197 or equivalent, providing ductility and resistance to mechanical stress.
• ✅ NPT Threads Tapered threads conform to ANSI/ASME B1.20.1 standards, ensuring compatibility and a leak-resistant seal with proper sealant.
• ✅ Pressure Rated Suitable for working pressures up to 150 PSI (non-shock) in liquid and gas systems depending on pipe schedule and system design.
• ✅ Thread Engagement Depth Optimized for full contact to minimize potential leak paths and maintain system integrity.
• ✅ Fire-Safe and Flame-Free Assembly Commonly used in fuel gas systems where welding or soldering is restricted or undesirable.

Technical Specifications

• Material: Black Malleable Iron
• Nominal Size: 1-1/2 inch FIP x FIP (Female Iron Pipe Thread)
• Thread Standard: ANSI/ASME B1.20.1
• Compliance: Typically conforms to ANSI/ASTM A197, A-153 (zinc coating if galvanized)
• Temperature Range: Up to 350°F depending on system media and sealant

Common Applications

Installed in fuel gas delivery lines, hydronic heating systems, compressed air lines, and non-potable water systems. Used in new construction, system retrofits, and repairs where precise alignment and secure threading are required.

Material Note

Black iron fittings are uncoated (no zinc galvanization) and intended for interior use or applications where corrosion is not a primary concern. For outdoor or corrosive environments, consider galvanized alternatives or additional corrosion protection.

Installation Guidelines

Apply thread sealant or PTFE tape to male threads before insertion. Tighten using properly sized wrenches on both the coupling and pipe section to avoid overtightening or thread damage. Adhere to local mechanical and fuel gas codes for all pressurized installations.