Sigma 819902651 Square Head Plug 3 Inch Mnpt 150 Lb

Product Description

The SIGMA 819902651 is a cored square head plug designed for use in threaded pipe systems requiring a reliable, pressure-rated closure. Built from malleable iron with a galvanized finish, this plug features a 3-inch nominal size with a male NPT (MNPT) end style, rated at 150 lb. The cored design allows the plug to be drilled out when a future tap or branch connection is needed. Licensed plumbers and pipefitters install this fitting in iron pipe systems where a removable, threaded closure is required. The galvanized coating provides corrosion resistance suited to both indoor and light outdoor service environments.

This square head plug is used in residential and commercial plumbing, fire protection, and industrial piping applications. The 150 lb pressure rating makes it appropriate for low- to moderate-pressure water, steam, and general service piping. The MNPT connection threads directly into a female-threaded pipe, fitting, or valve end. Domestically produced, it meets standard expectations for malleable iron threaded fittings in piping assemblies across a wide range of trade applications.

Key Features

• 3-inch nominal size for use in standard iron pipe systems
• MNPT end style threads directly into female-threaded fittings or pipe ends
• 150 lb pressure rating suitable for low- to moderate-pressure service
• Cored construction allows future drilling for branch taps
• Malleable iron with galvanized finish for corrosion resistance
• Domestically manufactured

Compatibility

Designed as a standard 150 lb malleable iron threaded fitting compatible with 3-inch MNPT female-threaded pipe ends, couplings, and fittings in iron pipe systems.

Installation Notes

Installation is typically performed by a licensed plumber or pipefitter following applicable IPC and IFGC code requirements. Shut off and depressurize the pipe system completely before installing or removing threaded plugs. Apply an appropriate thread sealant or PTFE tape to the MNPT threads before installation. Use a properly sized pipe wrench to achieve a secure, leak-free connection without over-tightening, which can crack malleable iron fittings.

Technical Specifications

• Nominal Size: 3 inches
• End Style: MNPT
• Pressure Rating: 150 lb
• Material: Malleable Iron
• Finish: Galvanized
• Origin: Domestic

Standard Information

• Brand: SIGMA
• Manufacturer Part Number: 819902651