Matco-norca zmbun03 Black Malleable Iron Union 1/2 in

Product Description

The MATCO-NORCA zmbun03 is a 1/2-inch black malleable iron union designed for use in gas piping, steam, and hydronic heating systems. A union fitting allows two sections of pipe to be joined and later disconnected without rotating the pipe itself, making it a critical component for serviceability in both new installations and retrofit work. The black finish indicates uncoated malleable iron, which is the standard material for gas distribution piping. Licensed plumbers and pipefitters install this fitting in residential and light commercial applications where future access for maintenance is required.

This union is suited for low-pressure gas lines, steam systems, and black iron pipe assemblies in residential and commercial settings. The 1/2-inch size fits standard Schedule 40 black iron pipe and is commonly used at appliance connections, meter sets, and branch line terminations where disconnection and reconnection of the line may be needed over the life of the system.

Key Features

• 1/2-inch pipe size fits standard black iron pipe assemblies
• Malleable iron construction provides strength and resistance to mechanical stress
• Union design allows pipe disconnection without rotating adjacent pipe sections
• Black finish is standard for gas piping applications per common installation practice
• Threaded end connections for direct assembly with NPT-compatible fittings and pipe

Compatibility

Designed as an OEM-style replacement or new-installation fitting for 1/2-inch black iron pipe systems, including gas distribution and steam piping assemblies.

Installation Notes

This fitting is installed by licensed plumbers or pipefitters in jurisdictions governed by the International Fuel Gas Code (IFGC) or International Plumbing Code (IPC). Shut off and isolate the gas supply or system pressure before disassembling or threading any union fitting. Use appropriate pipe thread sealant rated for the intended service medium — not all sealants are approved for gas service. Inspect threads on both the fitting and the pipe for damage before assembly.

Technical Specifications

• Pipe Size: 1/2 inch
• Material: Black Malleable Iron
• Connection Type: Threaded (NPT)

Standard Information

• Brand: MATCO-NORCA
• Manufacturer Part Number: zmbun03