Sigma 810089805 Fig 3121R Reducing Coupling 2x0.5in Fnpt

Product Description

The SIGMA 810089805 is a FIG 3121R malleable iron reducing coupling designed to connect pipe runs of two different diameters in threaded piping systems. With a 2 x 0.5 inch nominal size and female NPT (FNPT) end style on both ends, this fitting transitions from a 2-inch line down to a 0.5-inch line without additional adapters. Rated at 150 lb, it carries a black oxide finish that provides a base level of corrosion resistance. Plumbers and pipefitters install this fitting in low-pressure gas, water, and steam distribution systems where reducing the pipe diameter is required at a branch or terminal connection.

This reducing coupling is suited for residential and light commercial plumbing and mechanical piping applications. It is a standard 150 lb class threaded fitting, making it appropriate for systems where pipe is joined using tapered NPT threads. Typical installation scenarios include supply line reductions, branch takeoffs, and equipment connections where a larger main line feeds a smaller-diameter outlet. The black oxide finish is standard for black iron pipe systems used in gas distribution and similar applications.

Key Features

• Reduces from 2 inch nominal to 0.5 inch nominal in a single fitting
• FNPT threads on both ends for standard tapered thread engagement
• 150 lb pressure class rating suitable for low-pressure service
• Malleable iron construction provides strength and impact resistance
• Black oxide finish standard for black iron gas and mechanical piping systems

Compatibility

Designed as an OEM-style replacement and standard fitting for 150 lb malleable iron threaded piping systems using NPT connections.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable IPC or IFGC requirements. Shut off and depressurize the system fully before removing or installing any threaded fittings. Apply an appropriate thread sealant or PTFE tape to the male NPT threads before assembly. Do not overtighten, as malleable iron threads can crack under excessive force.

Technical Specifications

• Nominal Size: 2 x 0.5 inches
• End Style: FNPT (Female NPT) both ends
• Pressure Class: 150 lb
• Material: Malleable Iron
• Finish: Black Oxide
• Figure Number: FIG 3121R

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 810089805