Cast Iron
Typically gray cast iron or ductile iron; low cost and hard texture; suitable for standard water and gas transport pipelines and common indoor fire protection systems. Drawbacks include moderate strength, susceptibility to rust, and a shorter service life.
Carbon Steel
High strength and good machinability; can be galvanized to enhance corrosion resistance; offers excellent cost-effectiveness. Suitable for most indoor and outdoor fire protection and water supply/drainage applications; performs reliably in humid environments lacking strong corrosive agents.
Stainless Steel
Commonly made from 304 or 316L grades; features excellent corrosion resistance and a smooth surface that resists fouling; meets hygiene standards. Suitable for food processing, pharmaceuticals, chemicals, and other applications requiring high cleanliness or corrosion resistance; offers a long service life but comes at a relatively higher cost.
Other Special Materials
Some large-diameter, heavy-duty models utilize cast steel or DZ 20# steel combined with plastic-coated or powder-coated finishes. These are designed for high-pressure conditions exceeding 2.5 MPa and are commonly used in municipal utility tunnels and heavy-duty industrial piping systems.