1 inch x 4 inch Black Steel Nipple

1 Inch x 4 Inch Black Steel Nipple – Schedule 40, Threaded MIP x MIP

The 1 inch x 4 inch black steel nipple is a straight pipe fitting used to connect two female-threaded components in pressurized systems. Manufactured from Schedule 40 welded black steel pipe, this nipple features male NPT threads on both ends and is designed for applications involving gas, air, water, and oil in both residential and commercial piping systems.

Material and Compliance Standards

This nipple is fabricated from ASTM A53 Grade A or equivalent carbon steel pipe, with factory-cut threads conforming to ASME B1.20.1. The black (uncoated) finish is suitable for systems not requiring corrosion protection or where paint or pipe wrap will be applied post-installation. Typical use includes above-ground indoor installations in mechanical rooms, gas distribution manifolds, and process piping systems.

• ✅ Material: Welded black steel pipe (carbon steel per ASTM A53)
• ✅ Wall Rating: Schedule 40
• ✅ Thread Type: NPT (National Pipe Taper), both ends
• ✅ Length: 4 inches overall (threaded nipple length includes thread engagement)
• ✅ Conformance: ASME B1.20.1, ASTM A733 (threaded pipe nipples)

Installation Guidelines

Use approved thread sealants such as PTFE tape or non-hardening pipe joint compound suitable for the service media. Thread engagement should follow ANSI/ASME pipe joint specifications to avoid over-tightening, which may crack connected fittings. This nipple is not intended for potable water systems or underground installations unless treated or coated accordingly.

Applications

Commonly used in fuel gas piping (natural gas or propane), low-pressure steam, hydronic heating loops, compressed air systems, and general-purpose process lines. Suitable for use with cast iron, black malleable iron, forged steel, or carbon steel fittings. Also applicable in fire sprinkler systems if specified for dry systems or pre-action installations.

Code Compliance Note

Black steel pipe and nipples are acceptable under IPC and NFPA codes for gas and non-potable fluid transport. Always confirm with the authority having jurisdiction (AHJ) for regional acceptance and application-specific requirements, particularly in gas installations under NFPA 54 or mechanical code provisions.