Bk 521-964BG Black Iron Hex Bushing 1-1/4 X 3/4 in

Product Description

The BK 521-964BG is a black malleable iron hex bushing used to reduce pipe thread sizes in black iron piping systems. It transitions a 1-1/4 inch male NPT thread down to a 3/4 inch female NPT thread, making it a standard reducing fitting for gas, air, and general fluid piping. Plumbers and pipefitters install this type of bushing when connecting a larger-diameter pipe to a smaller-diameter fitting or valve. The hexagonal body allows for wrench engagement during installation. Each unit is individually flag tagged and 100% inspected and quality tested before leaving the factory.

This hex bushing is suited for residential and light commercial piping applications including natural gas lines, propane distribution, compressed air systems, and water piping where black iron fittings are specified. It is a standard reducing bushing used wherever a 1-1/4 inch line must transition to a 3/4 inch threaded connection. The Mueller logo is cast into the body of each fitting, consistent with BK line production standards.

Key Features

• Black malleable iron construction meeting ANSI/ASTM A-197 material specification
• 1-1/4 inch male NPT thread x 3/4 inch female NPT thread reducing configuration
• Hex body design for secure wrench grip during installation
• Threads conform to ANSI B1.20.1 for reliable, leak-resistant engagement
• Dimensions meet ANSI/ASME B16.3, B16.14, and B16.39 standards
• 100% inspected and quality tested; individually flag tagged

Compatibility

Designed as an OEM-style replacement or new-installation fitting for black iron threaded pipe systems using 1-1/4 inch to 3/4 inch NPT reducing connections.

Installation Notes

Installation of black iron pipe fittings should be performed by a licensed plumber or pipefitter in accordance with applicable codes such as the IFGC or IPC. Apply an approved pipe thread sealant or PTFE tape rated for the intended service before threading the bushing into the female fitting. Use a pipe wrench on the hex body and do not overtighten, as malleable iron fittings can crack under excessive force. Shut off and depressurize the line completely before beginning any fitting replacement or new installation work.

Technical Specifications

• Material: Black Malleable Iron
• Male Thread Size: 1-1/4 inches NPT
• Female Thread Size: 3/4 inches NPT
• Thread Standard: ANSI B1.20.1
• Material Standard: ANSI/ASTM A-197
• Dimension Standards: ANSI/ASME B16.3, B16.14, B16.39
• Weight: 0.371 pounds
• Sold As: Each

Standard Information

• Brand: BK
• Manufacturer Part Number: 521-964BG