Sigma 812508208 Ground Joint Pipe Union 3/4 in Fnpt 150 Lb

Product Description

The SIGMA 812508208 is a FIG 3463 ground joint pipe union rated for 150 lb service in black malleable iron. Ground joint unions use a precision-machined metal-to-metal seat at the center connection, creating a reliable seal without a gasket or soft seat. The FNPT (female national pipe thread) end connections make this union compatible with standard threaded pipe systems. Plumbers and pipefitters install this fitting where a threaded pipe run must be disconnected for service or replacement without cutting pipe.

This union is suited for residential and light commercial plumbing, heating, and gas distribution systems where a 3/4 inch threaded connection is required. The 150 lb pressure rating covers typical low- and medium-pressure service in hot water heating, steam, and gas piping applications. The black finish is standard for gas and steam service and distinguishes these fittings from galvanized water-service fittings on a job site.

Key Features

• Ground joint metal-to-metal seat provides a durable, gasket-free seal
• 3/4 inch nominal size with FNPT end connections on both sides
• 150 lb pressure rating suitable for steam, gas, and hydronic heating lines
• Black malleable iron construction resists the rigors of gas and steam service
• FIG 3463 pattern conforms to standard union dimensional requirements

Compatibility

Designed as an OEM-style replacement fitting for standard 3/4 inch NPT threaded pipe systems in plumbing, gas, and hydronic heating applications.

Installation Notes

Installation is performed by licensed plumbers or pipefitters in accordance with applicable local codes and the International Fuel Gas Code or International Plumbing Code where required. Shut off and depressurize the pipe system and allow it to cool before disassembling or installing any union. Apply thread sealant or listed pipe thread compound to the male threads before making up the joint, and tighten with pipe wrenches to a wrench-tight connection. Do not over-torque malleable iron fittings, as the material is not as ductile as steel and can crack under excessive force.

Technical Specifications

• Figure Number: FIG 3463
• Nominal Size: 3/4 inch
• End Style: FNPT
• Pressure Rating: 150 lb
• Material: Malleable Iron
• Finish: Black

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 812508208