Sigma 810086819 Reducing Coupling 1x3/4 in Fnpt 150 Lb

Product Description

The SIGMA 810086819 is a malleable iron reducing coupling designed for threaded pipe assemblies in plumbing, mechanical, and industrial piping systems. It connects a 1-inch nominal pipe to a 3/4-inch nominal pipe using female NPT (FNPT) threads on both ends. Rated at 150 lb, this fitting handles standard working pressures common to low- and medium-pressure piping systems. The black oxide finish provides a degree of corrosion resistance for interior and protected installations. Plumbers and pipefitters install this fitting where a reduction in pipe diameter is required along a run.

This reducing coupling is suited for residential and light commercial plumbing, hydronic heating systems, gas distribution piping, and general mechanical piping where malleable iron fittings are specified. The FNPT end style allows direct threading onto standard NPT-threaded pipe without additional adapters. It follows the dimensional and pressure standards associated with 150 lb malleable iron threaded fittings, making it a common choice for service, repair, and new construction work.

Key Features

• 1 inch by 3/4 inch nominal reducing configuration for inline pipe diameter transitions
• Female NPT threads on both ends for standard threaded pipe connections
• 150 lb pressure class for compatibility with standard working-pressure systems
• Malleable iron construction provides strength and impact resistance in threaded fittings
• Black oxide finish for surface protection in interior and sheltered installations

Compatibility

Designed as an OEM-style replacement and standard-stock fitting for 150 lb malleable iron threaded piping systems using 1 inch to 3/4 inch nominal NPT pipe connections.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable mechanical and plumbing codes, including IPC and IFGC requirements where gas service is involved. 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 threads before assembly. Do not overtighten, as malleable iron threads can crack under excessive torque.

Technical Specifications

• Nominal Size: 1 x 3/4 inches
• End Style: FNPT (Female National Pipe Thread) both ends
• Pressure Rating: 150 lb
• Material: Malleable Iron
• Finish: Black Oxide

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 810086819