Sigma 811087006 Galvanized Reducing Coupling 1x1/2 in Fnpt

Product Description

The SIGMA 811087006 is a malleable iron galvanized reducing coupling designed for threaded pipe systems in plumbing, HVAC, and industrial piping applications. Configured as a FIG 3121R reducing coupling, it connects a 1-inch nominal pipe to a 1/2-inch nominal pipe using female NPT (FNPT) threads on both ends. Rated at 150 lb, this fitting handles standard working pressures found in low- to medium-pressure gas, water, and air distribution systems. The hot-dip galvanized finish provides corrosion resistance suitable for exposed or mildly corrosive environments. Malleable iron construction offers the toughness and thread engagement reliability expected in professional piping work.

This reducing coupling is used wherever a pipe run transitions from 1-inch to 1/2-inch nominal pipe. Typical applications include residential and light commercial plumbing supply lines, natural gas distribution piping, compressed air systems, and steam lines operating within 150 lb pressure class limits. It is installed by licensed plumbers, pipefitters, and HVAC technicians as part of threaded pipe assemblies.

Key Features

• Reduces 1-inch nominal to 1/2-inch nominal pipe in a single fitting
• FNPT threads on both ends for standard threaded pipe connection
• 150 lb pressure class rating suitable for water, gas, and air service
• Malleable iron construction provides impact resistance and reliable thread engagement
• Galvanized finish for corrosion protection in exposed or damp environments
• FIG 3121R pattern — a widely recognized reducing coupling configuration

Compatibility

Designed as a standard 150 lb malleable iron reducing coupling compatible with 1-inch x 1/2-inch NPT threaded pipe systems. Suitable for use with Schedule 40 black or galvanized steel pipe in water, gas, and compressed air service within the 150 lb pressure class.

Installation Notes

Installation is performed by licensed plumbers or pipefitters following applicable IPC or IFGC code requirements for the service type. Shut off and depressurize the system completely before disassembling or modifying any threaded connection. Apply an approved thread sealant or PTFE tape to male threads before assembly; do not apply sealant to female threads. Tighten to hand-tight plus a wrench-turn appropriate for the pipe size — do not overtighten malleable iron fittings, as this can crack the fitting body.

Technical Specifications

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

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 811087006