Sigma 811080209 Fig 3121 Galvanized Pipe Coupling 1/2 in Fnpt

Product Description

The SIGMA 811080209 is a FIG 3121 malleable iron pipe coupling with a galvanized finish, designed for joining two threaded pipe sections in a straight run. Rated at 150 lb, this fitting accepts female NPT (FNPT) connections on both ends and is sized for 1/2 inch nominal pipe. The galvanized coating provides corrosion resistance in exposed or moderately harsh service environments. Plumbers and pipefitters install this type of coupling in water supply, gas distribution, and general industrial piping systems where a reliable, pressure-rated threaded connection is required.

This coupling is suited for residential and light commercial plumbing and gas piping applications. It is commonly installed in pipe runs that require a full-thread union of two pipe ends without change in direction or pipe size. The FNPT end style is compatible with standard NPT-threaded pipe and fittings. The 150 lb pressure class makes it appropriate for low- to medium-pressure service lines where malleable iron fittings are specified.

Key Features

• FIG 3121 straight coupling configuration for in-line pipe joining
• FNPT connections on both ends accept standard NPT-threaded pipe
• 150 lb pressure rating suitable for low- to medium-pressure systems
• Malleable iron construction provides strength and impact resistance
• Galvanized finish adds corrosion protection for exposed installations

Compatibility

Designed as an OEM-style replacement or standard trade fitting for 1/2 inch nominal NPT-threaded pipe systems using 150 lb malleable iron fittings.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable local codes, the International Plumbing Code (IPC), or the International Fuel Gas Code (IFGC) where applicable. Shut off and depressurize the pipe system completely before removing or installing any threaded fittings. Apply an appropriate thread sealant or PTFE tape to the male threads before assembly and tighten to hand-tight plus the appropriate number of turns for the pipe size per standard trade practice. Do not overtighten malleable iron fittings, as cracking can occur.

Technical Specifications

• Figure Number: FIG 3121
• Nominal Pipe Size: 1/2 inch
• End Style: FNPT (Female National Pipe Thread) both ends
• Pressure Rating: 150 lb
• Material: Malleable Iron
• Finish: Galvanized

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 811080209