Bk 521-943BG Black Iron Hex Bushing 3/4 X 1/2 Inch

Product Description

The BK 521-943BG is a black malleable iron hex bushing designed to reduce a 3/4 inch male NPT connection to a 1/2 inch female NPT connection. This hexagon-style bushing is a standard pipe fitting used to join pipes or components of different thread sizes in gas, air, and liquid distribution systems. Each unit is individually flag tagged and carries the Mueller logo cast directly into the body. The fitting is 100 percent inspected and quality tested before leaving the factory. It meets ANSI/ASTM A-197 material standards, ANSI/ASME B16.14 and B16.39 dimensional standards, and ANSI B1.20.1 thread specifications.

This hex bushing is suited for residential and light commercial plumbing, gas distribution, and mechanical piping applications where a threaded size reduction is needed in a black iron system. Plumbers and pipefitters typically use this fitting when transitioning between pipe sizes on black iron gas lines, compressed air lines, or hydronic heating systems. The hexagon body allows standard wrench engagement for secure installation without distorting the fitting.

Key Features

• Black malleable iron construction meets ANSI/ASTM A-197 material specification
• 3/4 inch male NPT to 1/2 inch female NPT hex bushing configuration
• Threads conform to ANSI B1.20.1 for reliable seating and leak-free makeup
• Dimensions meet ANSI/ASME B16.14 and B16.39 standards
• Mueller logo cast into the body; individually flag tagged for easy identification
• 100 percent inspected and quality tested

Compatibility

Designed as a standard ANSI/ASME-compliant threaded hex bushing for use in black iron pipe systems requiring a 3/4 inch to 1/2 inch NPT reduction.

Installation Notes

Installation is typically performed by licensed plumbers or pipefitters working on threaded black iron systems. Shut off and depressurize the line completely before disassembling or installing any threaded fittings. Apply an approved pipe thread sealant or PTFE tape to the male threads before makeup, following local code requirements such as the IFGC or IPC. Use a properly sized pipe wrench on the hex body to avoid damaging the fitting or adjacent components.

Technical Specifications

• Material: Black malleable iron, ANSI/ASTM A-197
• Inlet Thread (Male): 3/4 inch NPT
• Outlet Thread (Female): 1/2 inch NPT
• Thread Standard: ANSI B1.20.1
• Dimensional Standard: ANSI/ASME B16.14, B16.39
• Weight: 0.118 pounds
• Unit of Measure: Each

Standard Information

• Brand: BK
• Manufacturer Part Number: 521-943BG