Nibco B305356 Cast Copper Companion Pipe Flange 125 Psi

Product Description

The NIBCO B305356 is a cast copper companion pipe flange rated for 125 psi service. It is designed for use on 1-inch pipe with an outside diameter of 4-1/4 inches and bolt hole centers measuring 3-1/8 inches across. The flange features a C-style end connection and is manufactured from cast copper alloy conforming to ASTM B584. Companion flanges are used to join pipe sections at valves, equipment connections, or system access points. Licensed plumbers and pipefitters install this fitting in copper piping systems where a bolted flange joint is required.

This flange is suited for plumbing and mechanical piping systems operating within its 125 psi pressure rating. The cast copper construction makes it appropriate for water service, hydronic heating, and similar fluid-handling applications where copper is the specified pipe material. It is installed as a companion flange, meaning it pairs with a matching flange on the adjoining component to form a bolted, gasketed connection. The C end connection style is compatible with standard copper pipe joining methods.

Key Features

• Cast copper construction per ASTM B584 for durability in fluid-handling service
• Rated at 125 psi working pressure
• C-style end connection for standard copper pipe joining
• 1-inch pipe size with 4-1/4 inch overall outside diameter
• Bolt hole centers at 3-1/8 inches for consistent bolt-pattern alignment
• Companion flange design pairs with matching flange for bolted joint assembly

Compatibility

Designed as an OEM-style companion flange for 1-inch copper piping systems operating at Class 125 pressure ratings.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable IPC and local plumbing codes. Shut off and depressurize the system fully before disassembling any existing flange connection. Use a properly rated gasket between mating flange faces and tighten bolts in a cross pattern to ensure even seating. Do not exceed the 125 psi pressure rating of this fitting.