2-1/2 inch x 6 inch Black Steel Nipple

2-1/2" x 6" Black Steel Pipe Nipple – Schedule 40, Threaded Both Ends

The 2-1/2" x 6" black steel nipple is manufactured from Schedule 40 welded carbon steel pipe, threaded on both ends per ANSI B1.20.1 specifications. This fitting is designed for industrial and commercial mechanical systems requiring a rigid, pressure-rated connection between two female-threaded components.

Constructed to meet ASTM A53 and A106 standards, the nipple is suitable for use in gas distribution, fire protection loops (non-potable), low-pressure steam, air systems, and closed-loop hydronic circuits. Black steel, unlike galvanized alternatives, is appropriate for fuel gas and other applications where zinc-free material is specified.

Product Specifications

• ✅ Material: Carbon steel pipe (ASTM A53, Grade A or B)
• ✅ Finish: Black oxide (uncoated steel)
• ✅ Size: 2-1/2" NPS x 6" overall length
• ✅ Wall Thickness: Schedule 40
• ✅ Thread Type: NPT – tapered thread, both ends
• ✅ Operating Conditions: Pressure and temperature ratings per ASME B31.3 design parameters

Installation Guidelines

Threaded steel nipples must be installed using appropriate sealing compounds or PTFE tape rated for the system’s media. Use of pipe wrenches is recommended to achieve required thread engagement without over-torquing. Installers should verify alignment and support to reduce joint fatigue or misalignment in systems with thermal or mechanical cycling.

Application Areas

This fitting is commonly used in:

• • Fuel gas piping systems (natural gas, propane)
• • Low-pressure steam distribution and returns
• • Air compressor piping and industrial manifolds
• • Hydronic heat loops and return headers
• • Fire pump suction or auxiliary lines (non-potable)

Material Insight

Black steel pipe is preferred in gas and mechanical systems due to its strength, machinability, and thermal resistance. Unlike galvanized steel, it is suitable where zinc leaching or flaking is a concern, particularly under elevated temperature or pressure service conditions.