Ductile iron threaded fittings are pipe fittings offer lighter, stronger, and more durable connections than other threaded fittings. They have twice the strength of cast iron threaded fittings, but only half the weight. In the manufacturing process, magnesium and ferrosilicon make regular cast iron form nodule-shaped crystallized graphite, creating a light material that is very strong: ductile iron. Ductile iron threaded fittings can have a tensile strength of up to 120,000 psi when heated properly, far greater than the 21,000 to 31,000 psi strength of cast iron fittings.

Threaded fittings connect (or close off) the ends of threaded pipes. They can also change the direction of pipes. Male threads on the outside of the pipes can be fitted into female threads inside the fittings, or the other way around. This means that threaded pipe fittings often carry the weight loads of the adjoining pipes. Ductile iron threaded fittings can carry twice as much weight as gray cast iron fittings. The reduced weight of ductile iron can also significantly decrease freight and logistics costs without compromising quality.

The construction, utility, and fire protection industries rely heavily on ductile iron threaded fittings for pipe connections. Large-scale construction applications require threaded fittings that are easy to install and cheap to transport. The durability of ductile iron threaded fittings ensures that pipes stay connected and protected for a long time. Threaded fittings come in a variety of shapes and sizes to fit all kinds of pipes.