Bk 521-976BG Black Iron Hex Bushing 1-1/2 X 1-1/4 in

Product Description

The BK 521-976BG is a hexagonal pipe bushing made from black malleable iron, designed to reduce a 1-1/2 inch male NPT thread down to a 1-1/4 inch female NPT thread. This style of hex bushing is a standard component in black iron piping systems used for natural gas, propane, and steam distribution. Each fitting is individually flag tagged and carries the Mueller logo cast directly into the body. The part meets ANSI/ASTM A-197 material standards, with dimensions conforming to ANSI/ASME B16.14 and B16.39 and threads cut to ANSI B1.20.1. It ships as a single unit and is 100 percent inspected and quality tested before leaving the factory.

This hex bushing is suited for residential and light commercial piping installations where a threaded reduction is needed between two different pipe sizes. Typical applications include gas line rough-in, boiler piping, steam systems, and general black iron pipe assemblies. Plumbers and pipefitters install this fitting when connecting a larger-diameter pipe or valve to a smaller-diameter run. The hexagonal profile allows a pipe wrench or open-end wrench to seat properly during assembly, making it straightforward to thread and tighten in tight spaces.

Key Features

• Black malleable iron construction meets ANSI/ASTM A-197 material specification
• 1-1/2 inch male NPT inlet reduces to 1-1/4 inch female NPT outlet
• Hexagonal body provides positive wrench engagement during installation
• Threads conform to ANSI B1.20.1 for reliable sealed connections
• Dimensions meet ANSI/ASME B16.14 and B16.39 standards
• 100 percent inspected and quality tested; individually flag tagged

Compatibility

Designed as a standard NPT threaded hex bushing for use in black iron pipe systems conforming to ANSI/ASME B16.14 and B16.39 dimensional standards.

Installation Notes

This fitting is typically installed by licensed plumbers or pipefitters working on gas, steam, or hydronic systems. Shut off the gas supply or depressurize the system completely before removing or installing any threaded fittings. Apply an approved pipe thread sealant or PTFE tape rated for the service medium to all male threads before assembly. Follow all applicable local codes and IFGC or IPC requirements for pipe jointing and pressure testing.

Technical Specifications

• Material: Black Malleable Iron
• Inlet Size: 1-1/2 inches Male NPT
• Outlet Size: 1-1/4 inches Female NPT
• Body Style: Hexagon
• Material Standard: ANSI/ASTM A-197
• Dimensional Standard: ANSI/ASME B16.14, B16.39
• Thread Standard: ANSI B1.20.1
• Weight: 0.339 pounds
• Sold As: Each

Standard Information

• Brand: BK
• Manufacturer Part Number: 521-976BG