Bk Mueller 511-321HC Reducing Coupling 3/8 X 1/4 in

Product Description

The BK MUELLER 511-321HC is a malleable iron reducing coupling designed to connect pipes of two different diameters using threaded end connections. Rated at 300 psi for liquid and gas service and 150 psi for steam, this Class 150 fitting handles the pressure demands of standard commercial and residential piping systems. The galvanized finish provides corrosion resistance in both exposed and concealed installations. Plumbers and pipefitters install this coupling where a 3/8-inch pipe must transition down to a 1/4-inch pipe in a threaded system.

This reducing coupling is suited for use in residential and light commercial plumbing, gas distribution, and steam piping applications where a threaded pipe size reduction is required. The 3/8 x 1/4 inch configuration makes it a common transition fitting in supply lines, instrumentation connections, and compressed air or gas branch lines. Its malleable iron construction performs reliably across a wide range of fluid and gas media within its rated pressure limits.

Key Features

• Reduces from 3/8-inch to 1/4-inch threaded pipe connections
• Rated 300 psi for liquid and gas service
• Rated 150 psi for steam service
• Class 150 malleable iron construction for durability under cyclic loading
• Galvanized finish for corrosion resistance
• Threaded end connections for standard NPT installation

Compatibility

Designed as an OEM-style threaded reducing coupling for 3/8-inch to 1/4-inch NPT piping systems in plumbing, gas, and steam service applications rated within Class 150 limits.

Installation Notes

Installation is performed by a licensed plumber or pipefitter. Shut off and depressurize the affected line before disassembly or fitting installation. Apply appropriate thread sealant or PTFE tape to all male threads per the applicable piping code, such as the IPC or IFGC. Do not exceed the published pressure ratings for the intended service medium.