1-1/4 inch x 3/4 inch Black Iron Bushing

1-1/4" x 3/4" Black Malleable Iron Hex Bushing – Threaded Reducing Fitting for Pipe Size Transition

The 1-1/4" x 3/4" Black Iron Bushing is a hex-head, reducing fitting used to connect two pipes of differing nominal sizes in threaded piping systems. It features a 1-1/4" male National Pipe Thread (NPT) on the exterior and a 3/4" female NPT on the interior, enabling the reduction of system diameter while maintaining mechanical integrity in non-potable applications such as gas, steam, and oil piping.

Manufactured from black malleable iron in accordance with ASTM A197, this bushing is suitable for low- to medium-pressure systems requiring rigid, threaded components. The black oxide finish provides mild corrosion resistance in interior, dry installations where galvanization is not necessary.

Key Features

• ✅ Threaded NPT Ends: Male-to-female design for joining mismatched pipe diameters in a sealed, threaded configuration.
• ✅ Malleable Iron Body: Delivers mechanical strength for systems subjected to internal pressure and thermal variation.
• ✅ Hex Head Design: Allows easy installation using standard pipe wrenches or hex sockets for torque application.
• ✅ Pressure-Rated: Commonly used in Class 150 applications; refer to ANSI B16.3 for detailed specifications.

Technical Specifications

• Nominal Size: 1-1/4" Male NPT x 3/4" Female NPT
• Material: Malleable iron (ASTM A197)
• Finish: Black oxide-coated (non-galvanized)
• Conformance: Threads to ASME B1.20.1, fitting body to ANSI/ASME B16.3

Installation Guidelines

Apply PTFE tape or approved pipe thread compound to male threads before insertion. Use a pipe wrench or hex driver on the bushing's external flats for installation. Avoid overtightening to prevent thread damage or stress cracking. Confirm compatibility with system pressure ratings and media requirements prior to use.

Typical Applications

This fitting is typically used in fuel gas distribution, compressed air lines, steam condensate systems, and general mechanical piping where a transition from 1-1/4" to 3/4" threaded components is needed. It is intended for use in non-corrosive environments or interior installations where black iron fittings are accepted by code.

Material Note

Black iron fittings are not approved for potable water systems. For applications involving water or corrosive fluids, galvanized or alternative corrosion-resistant materials should be specified based on the medium and code requirements.

The 1-1/4" x 3/4" Black Iron Bushing provides a durable, threaded transition point for systems requiring reliable size reduction in accordance with standard plumbing and mechanical code practices.