Bk Mueller 511-332HN Malleable Iron Reducing Coupling

Product Description

The BK MUELLER 511-332HN is a malleable iron reducing coupling designed to connect pipes of two different diameters in threaded piping systems. It transitions from a 1/2-inch to a 3/8-inch threaded connection, making it a standard fitting choice for reducing line size within a run of pipe. The fitting carries a Class 150 rating and is pressure-rated at 300 psi for liquid and gas service and 150 psi for steam service. A galvanized finish provides corrosion resistance in demanding environments. Plumbers and pipefitters install this type of coupling as part of gas distribution, water supply, and steam piping assemblies.

This reducing coupling is suited for residential and light commercial piping applications. Typical uses include natural gas distribution lines, compressed air systems, water supply runs, and low-pressure steam systems where a step-down in pipe size is required. The threaded end connections conform to standard NPT specifications, allowing straightforward integration into existing threaded iron pipe systems.

Key Features

• Reduces from 1/2-inch to 3/8-inch pipe size in a single fitting
• Threaded (NPT) end connections on both ends
• 300 psi liquid and gas pressure rating
• 150 psi steam pressure rating
• Class 150 malleable iron construction
• Galvanized finish for corrosion resistance

Compatibility

Designed as an OEM-style replacement or new-installation fitting for standard NPT threaded malleable iron pipe systems rated at Class 150.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable local codes, including the International Plumbing Code and International Fuel Gas Code where gas service is involved. Shut off the gas or water supply and relieve system pressure completely before making any connections. Apply an approved thread sealant or PTFE tape to all male threads before assembly. Do not overtighten threaded fittings, as malleable iron threads can be damaged by excessive force.