2 inch Black Iron Union Female x Female

2" Black Malleable Iron Union – FNPT x FNPT for Threaded Pipe Systems

The 2" Black Iron Union is a three-piece, female-threaded fitting designed to join two sections of threaded steel pipe in low- to medium-pressure applications. Manufactured from ASTM A197 malleable iron, this union provides a disassemblable connection point, allowing for maintenance access or future system modifications without cutting pipe.

Finished with a protective black coating and precision-cut NPT threads, the union ensures secure sealing in steam, gas, oil, and hydronic heating systems. The union's design includes a ground joint seat to maintain alignment and compression integrity during system operation.

Product Features

• ✅ Threaded Connections: Female National Pipe Thread (FNPT) ends per ASME B1.20.1 for compatibility with schedule 40 and 80 steel pipe.
• ✅ Ground Joint Seat: Precision-machined seat provides metal-to-metal contact for improved sealing and alignment under thermal cycling.
• ✅ Material: Black malleable iron conforming to ASTM A197 for high tensile strength and dimensional stability.
• ✅ Temperature and Pressure Ratings: Suitable for working pressures up to 300 PSI and operating temperatures up to 366°F, depending on media and installation conditions.
• ✅ Reusability: Union design allows repeated assembly/disassembly without thread damage, supporting maintenance and system adjustments.

Specifications

• Nominal Size: 2 inches
• Connection Type: FNPT x FNPT Union
• Material: Malleable iron, black finish
• Standards: ASTM A197, ASME B16.3, ASME B1.20.1 (threads), UL/CSA listings where applicable

Installation Notes

Apply appropriate thread sealant or PTFE tape to male pipe threads before tightening. Use pipe wrenches on both fittings to ensure torque is applied correctly and avoid stressing adjacent joints. Avoid overtightening, which may distort threads or crack the union body. Not for use in potable water systems unless specifically rated for lead-free compliance.

Application Scope

Used extensively in mechanical rooms, gas and oil systems, hydronic heat distribution, and process piping layouts where isolation or future disassembly is required. Suitable for both horizontal and vertical pipe runs in commercial and industrial settings.

Service Note

Black iron unions are not recommended for corrosive environments or direct burial unless externally protected. For pressurized water systems, verify compatibility with project specifications and sealing requirements.

The 2" Black Malleable Iron Union offers a durable and serviceable joint for threaded steel piping networks. Its field-proven design supports system longevity and access in demanding mechanical applications.