2 inch Square Head Black Cast Iron Plug

2" Black Cast Iron Plug – Square Head Threaded Fitting for Pipe Termination

The 2" Black Cast Iron Square Head Plug is a heavy-duty threaded fitting used to terminate the end of a female-threaded iron or steel pipe in non-pressurized or low-pressure plumbing, gas, and hydronic heating systems. Fabricated from durable black cast iron, it offers structural integrity and corrosion resistance in demanding mechanical and utility applications.

This plug features tapered male National Pipe Thread (NPT) for secure engagement and a square head design to enable positive tool grip during installation or removal. It is designed for compatibility with standard malleable iron or cast fittings and piping systems manufactured to ASME and ANSI dimensional specifications.

Key Characteristics for Mechanical Applications

• ✅ Cast Iron Construction – Offers excellent mechanical strength and temperature resistance for use in utility piping, drain lines, and mechanical rooms.
• ✅ Square Head Profile – Facilitates wrench tightening and easy removal, even in recessed or confined locations.
• ✅ Male NPT Threads – Precision-cut threads conform to ANSI B1.20.1 for leak-resistant, pressure-rated connections.
• ✅ Corrosion Protection – Black oxide finish resists surface rust in dry environments and during handling.

Technical Specifications

• Material: Black Cast Iron
• Nominal Size: 2 inch
• Connection Type: Male NPT (tapered thread)
• Head Type: Square
• Standards: Conforms to ANSI/ASME B16.3 and B1.20.1 specifications

Installation Guidelines

Apply PTFE thread sealant or pipe joint compound prior to threading into the mating female fitting. Tighten using a pipe wrench or adjustable wrench on the square head until snug—avoid excessive torque that could stress the fitting or the pipe threads. Intended for above-ground or accessible system locations where future removal may be necessary.

Application Scope

Typically used to seal unused or open pipe ports in gas distribution piping, closed-loop heating systems, air lines, and low-pressure drainage applications. Not intended for use with potable water or corrosive fluids unless specifically rated for those conditions.

Code and Material Use Notes

Black cast iron fittings are generally not approved for potable water systems and should be installed in accordance with local plumbing or mechanical codes. Always verify with project specifications and jurisdictional guidelines before use in inspected systems.