Sigma 811080811 Malleable Iron Pipe Coupling 1-1/4 in Fnpt 150 Lb

Product Description

The SIGMA 811080811 is a malleable iron pipe coupling designed to join two sections of pipe in threaded piping systems. Built to a 150 lb pressure rating, this FIG 3121 fitting uses female NPT (FNPT) threads on both ends to create a secure, inline connection. The galvanized finish provides corrosion resistance for use in demanding mechanical and plumbing environments. At 1-1/4 inch nominal size, this coupling fits standard pipe dimensions and is sized for commercial and light industrial applications. Licensed plumbers and pipefitters rely on this type of fitting for gas, water, and general mechanical piping systems where a durable threaded connection is required.

This coupling is suited for residential and commercial plumbing, HVAC hydronic piping, fire protection rough-in, and general mechanical piping installations. The 1-1/4 inch nominal size is a common diameter in branch and main supply lines across a wide range of building systems. The FNPT thread style conforms to standard NPT thread specifications, making it compatible with schedule 40 and schedule 80 threaded pipe applications where a full-coupling inline connection is needed.

Key Features

• 150 lb pressure rating suitable for standard-service threaded piping systems
• FNPT threads on both ends for inline pipe joining
• Malleable iron construction provides strength and resistance to mechanical stress
• Galvanized finish resists corrosion in wet and humid environments
• 1-1/4 inch nominal size fits standard NPT-threaded pipe
• FIG 3121 pattern for consistent fitment with standard coupling dimensions

Compatibility

Designed as an OEM-style replacement or new-installation fitting for standard 1-1/4 inch NPT threaded piping systems in plumbing, HVAC, and mechanical applications.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable local plumbing codes and IFGC or IPC requirements. Apply an appropriate thread sealant or PTFE tape to the male threads before assembly. Hand-tighten first, then use a pipe wrench to achieve proper thread engagement without over-torquing the fitting. Shut off and depressurize the piping system completely before removing or installing any threaded fittings.

Technical Specifications

• Nominal Size: 1-1/4 inches
• End Style: FNPT (Female National Pipe Thread) both ends
• Pressure Rating: 150 lb
• Material: Malleable Iron
• Finish: Galvanized
• Figure Number: FIG 3121

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 811080811