Manufactured from high-strength ductile iron via centrifugal casting. Internal cement mortar lining and external asphalt/epoxy coating greatly improve pressure resistance, seismic performance and service life. Ideal for drainage under municipal arterial roads, heavy-load roads, high-rise buildings, civil air defense projects, pipe galleries and high-temperature drainage areas
| Item | Technical Index | Remarks |
| Executive Standard | GB/T 26081-2022 | Complies with national standard |
| Nominal Outer Diameter | DN80-DN2600 | Custom available |
| Nominal Pressure Grade (PN) | PN10(1.0MPa)/PN16(1.6MPa, common for municipal works)/PN25(2.5MPa)/PN40(4.0MPa) | Select based on working conditions |
| Pressure Grade Class C (2026 New Standard, former K9 grade mainstream) | C25-2.5MPa (common, ≥DN700) C30-3.0MPa (common, DN350~600) C40-4.0MPa (common, ≤DN300) | Also applicable for gravity flow pipelines |
| Connection Method | Flexible socket joint with rubber ring / Flange joint / Mechanical joint | Reliable tightness |
| Standard Length | 6 m per piece | - |
A: K9 is the old wall thickness grade widely used in engineering. The 2026 new national standard cancels Class K and adopts Class C. For pipes within DN300, K9 is equivalent to C40; medium and large diameters correspond to C25/C30, and PN16 is commonly used for conventional projects.
A: Steel wire mesh skeleton composite pipe: Cover with tarpaulin to avoid long-term sun exposure.
Ductile iron pipe: Allowed for outdoor storage with pipe orifices protected.
A: Ductile iron has relatively high brittleness; avoid heavy impact in cold winter.