Sigma 813508611 Ground Joint Pipe Union 1 in Fnpt 150 Lb

Product Description

The SIGMA 813508611 is a FIG 3463 ground joint pipe union rated for 150 lb service in a 1-inch nominal pipe size. It features female national pipe taper (FNPT) end connections on both sides and is manufactured from galvanized malleable iron, providing corrosion resistance suitable for a range of piping applications. The ground joint design creates a metal-to-metal seat that delivers a reliable, leak-resistant connection without relying solely on threaded engagement. Licensed plumbers and pipefitters install this fitting in threaded piping systems where periodic disassembly is required for maintenance or service access.

This union is suited for use in residential and light commercial plumbing, hydronic heating, steam distribution, and general industrial piping systems operating within the 150 lb pressure class. The galvanized finish extends service life in environments where moisture exposure is a concern. The FNPT thread pattern conforms to standard NPT dimensions, making it compatible with standard threaded pipe and fittings throughout a system.

Key Features

• Ground joint metal-to-metal seat for a secure, leak-resistant threaded connection
• 1-inch nominal pipe size with FNPT end connections on both sides
• 150 lb pressure class rating for general service piping applications
• Malleable iron construction provides strength and impact resistance
• Galvanized finish for added corrosion protection in moisture-prone environments
• Allows pipe system disassembly without cutting or threading new pipe

Compatibility

Designed as an OEM-style replacement or new-installation fitting for standard 1-inch NPT threaded piping systems operating within the 150 lb pressure class.

Installation Notes

Installation of this union should be performed by a licensed plumber or pipefitter in accordance with applicable local plumbing codes and the International Plumbing Code (IPC). Shut off and depressurize the piping system completely before removing or installing any union fitting. Apply an appropriate thread sealant or PTFE tape to all male threaded connections before assembly. Do not over-tighten the union nut, as this can damage the ground joint seat and compromise the seal.

Technical Specifications

• Figure Number: FIG 3463
• Nominal Pipe Size: 1 inch
• End Style: FNPT (Female National Pipe Taper)
• Pressure Class: 150 lb
• Material: Malleable Iron
• Finish: Galvanized

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 813508611