What is a ductile iron pipe used for?

Ductile iron pipes, also known as ductile pipes, ductile iron pipes, or ductile cast pipes, are produced by adding nodulizing agents to molten iron with a casting grade of 18 or higher. These pipes are then centrifugally cast at high speed using a centrifugal ductile iron machine, resulting in what we call "ductile iron pipes." Widely used in piping systems, ductile iron pipes are a common sight. What are their specific applications? BAOWI STEEL is here to provide answers.

Ductile iron pipes, made from ductile iron, are characterized by their large diameter, thick walls, brittle texture, and low strength. However, they are cost-effective water supply materials with a normal service life of 20 to 25 years. As a type of cast iron pipe, ductile iron pipes must meet quality standards that require a nodulization grade of 1-3 (with a nodulization rate above 80%), significantly improving the material's mechanical properties. This gives the pipes the essence of iron combined with the performance of steel. After annealing, the microstructure of ductile iron pipes consists of ferrite with a small amount of pearlite, providing excellent mechanical properties, outstanding corrosion resistance, good ductility, effective sealing performance, and easy installation. They are primarily used in municipal and industrial applications for water supply, gas transport, and oil conveyance.

As the excellent performance of ductile iron becomes more widely recognized, these pipes are gradually replacing traditional gray cast iron pipes. Currently, ductile iron pipes are widely used in the following areas:

When ductile iron was first used for pipelines, most pipes and fittings were produced by major industrial nations, adhering to both national and international standards (such as ISO 2531). Compared to gray cast iron pipes, ductile iron pipelines are significantly superior for transporting water and other liquids. This is primarily due to the strength and toughness of ferritic ductile iron, which enables the pipes to withstand high operating pressures and tolerate rough handling during installation. Pipelines used for air or gas transport must endure multiple demands, such as excavation, municipal construction, and heavy traffic nearby. The high strength, excellent toughness, and straightforward installation of ductile iron pipes make them a definitive choice.

In terms of tonnage produced, the automotive industry is the second-largest consumer of ductile iron castings. These castings are used extensively in three main areas of vehicles:

(1) Engine components as a power source.

(2) Power transmission, including gears and shafts.

(3) Vehicle suspension, braking, and steering systems.

Modern agricultural practices demand reliable, long-lasting machinery. Ductile iron castings are widely used throughout the agricultural industry in components such as tractor parts, plow beams, brackets, clamps, and pulleys. For example, rear axle housings for agricultural vehicles, previously made from cast steel, are now commonly made of ductile iron. The road and construction industries also rely on a significant amount of equipment like bulldozers, pile drivers, cranes, and compressors, all of which incorporate ductile iron castings.

In the machine tool industry, ductile iron’s engineering properties allow for the design of complex machine components and heavy-duty castings exceeding 10 tons. Applications include injection molding plates, forging machine cylinders, and pistons. The high tensile and yield strength of ductile iron, along with its excellent machinability, enable the production of lightweight castings with maintained rigidity. Similarly, ductile iron’s strength and toughness make it ideal for hand tools such as wrenches, clamps, and measuring instruments.

In the paper industry, ductile iron’s high strength and elasticity modulus are utilized. Compared to gray cast iron, ductile iron offers 60% higher elasticity modulus, allowing the design of lighter pressure rollers and drying cylinders. Moreover, ductile iron rollers (with suitable nickel-chromium alloys) outperform steel and chilled cast iron in steel mill applications.

Valve manufacturers are major users of ductile iron, including austenitic ductile iron. Applications include successfully transporting various acids, salts, and alkaline liquids.

At BAOWI STEEL, we provide top-tier ductile iron products supported by a comprehensive global service network. From expert pre-sales advice to seamless after-sales installation support, our end-to-end solutions deliver reliability and efficiency at every stage.

Trust BAOWI STEEL for robust, eco-friendly, and cost-efficient piping systems relied upon by industry professionals around the globe.