Class K12 DN500 ductile iron pipe offers a 16 bar pressure rating in a 500 mm diameter, with cement-mortar lining and zinc-based external coating for over 100 years of service life. Its push-on K-type joints speed installation, while full compliance with ISO 2531, EN 545/598, ISO 4179, and ISO 8179 standards ensures global acceptance. Priced at roughly USD 510–546 per ton, it balances upfront cost and long-term savings, making it ideal for municipal, industrial, and irrigation networks.
Application Scenarios
Municipal water-supply systems rely on DN500 K12 pipes to transport drinking water at up to 16 bar, meeting BS EN 545 requirements for safety and flow capacity.
Sewerage and pressure-sewer networks use DN500 lines with EN 598 certification to handle effluent flow while resisting internal corrosion.
Agricultural irrigation and industrial cooling circuits benefit from ductile iron’s high tensile strength (≥ 270 MPa) and 7 % elongation, ensuring reliable performance under heavy loads.
Service Life & Durability
Modern ductile iron pipe is engineered for 100+ years of service thanks to GGG50 nodular iron, cement-mortar lining (ISO 4179), and zinc-based external coatings (ISO 8179-1/2).
Polyethylene sleeving (per AWWA C105/A21.5) adds an extra barrier in highly aggressive soils, virtually eliminating pitting and extending lifespan.
Laying & Connection
Push-On K-Type (Tyton) Joints
Built-in sockets with SBR/EPDM gaskets allow push-on assembly with ±5° angular deflection per joint, cutting installation time by up to 30 %.
Restrained & Flanged Options
For thrust-resistant or seismic applications, restrained-joint variants lock spigot and socket via cast-on lugs (EN 545). Flanged ends (EN 1092-2) ease maintenance in above-ground runs.
Compliance with International Standards
-
ISO 2531: Dimensions, pressure tests at 1.5× PN16
-
EN 545/EN 598: Water & sewer pipelines
-
ISO 4179: Cement-mortar lining
-
ISO 8179-1/2: Zinc/bitumen and zinc-rich paint coatings
-
ISO 9001: Quality management certified
Price Comparison with Other Series
| Thickness Class | Price (USD / ton) | Source |
|---|---|---|
| K7 | 450 – 550 | Alibaba |
| K9 | 530 – 550 | Alibaba |
| K12 | 510 – 546 | Alibaba |
| C25 | 400 – 500 | MFG Shop |
| C40 | 600 – 700 | MFG Shop |
Key Advantages
-
High Pressure Capacity: PN16 (16 bar) for large networks.
-
Excellent Ductility & Strength: GGG50 iron with Rp0.2 ≥ 270 MPa, A ≥ 7 %.
-
Superior Corrosion Protection: Multi-layer linings/coatings + sleeving options.
-
Rapid Installation: Push-on joints reduce labor and trench time.
-
Low Life-Cycle Cost: Minimal maintenance over a century, with energy-saving and recyclability benefits.
Frequently Asked Questions
Q1: What is the maximum operating pressure?
Up to 16 bar (PN16), tested at 1.5× pressure for safety.
Q2: When should I use restrained joints?
Choose restrained or flanged joints for steep gradients, high thrust zones, or seismic regions.
Q3: Are joint gaskets potable-water approved?
Yes—EPDM/SBR/NBR gaskets meet WRAS, NSF 61, and other potable-water standards.
Case Studies
-
Nîmes Métropole (France): Four DN500 UltraGrip flange adaptors successfully integrated new ductile iron sections around a flow meter, demonstrating reliable joint performance under tight tolerances.
-
U.S. Water Utility (DIPRA): Multiple municipalities report 100+ years of service with ductile iron mains, attributing zero major failures to robust linings and coatings.
-
Cost Savings Analysis: A U.S. study showed that over 50 years, ductile iron pipe can save utilities millions in present-value operating costs due to reduced energy and maintenance.
ductile iron pipe dimensions
| Pipe body weight （kg/m) | |||||||||||||||
| (Inside Diameter) | (Outside Diameter) | Socket Weight | K8 | K9 | K10 | C class | Total weight of Active Length=6M (kg) | Total weight of Active Length=5.7M (kg) | |||||||
| DN(mm) | OD(mm) | ≈ kg | Class | kg/m | K8 | K9 | K10 | C class | K8 | K9 | K10 | C class | |||
| 80 | 98 | 3.40 | 12.20 | 12.20 | 12.20 | C40 | 9.10 | 77.00 | 77.00 | 77.00 | 58.00 | 73.00 | 73.00 | 73.00 | 55.00 |
| 100 | 118 | 4.30 | 14.90 | 15.10 | 15.10 | C40 | 11.12 | 93.70 | 95.00 | 95.00 | 71.00 | 90.00 | 91.00 | 90.00 | 68.00 |
| 125 | 144 | 5.70 | 18.90 | C40 | 119.00 | ||||||||||
| 150 | 170 | 7.10 | 21.80 | 22.80 | 22.80 | C40 | 16.48 | 138.00 | 144.00 | 144.00 | 106.00 | 132.00 | 138.00 | 137.00 | 101.00 |
| 200 | 222 | 10.30 | 28.70 | 30.60 | 30.60 | C40 | 22.62 | 183.00 | 194.00 | 194.00 | 146.00 | 174.00 | 185.00 | 185.00 | 139.00 |
| 250 | 274 | 14.20 | 35.60 | 40.20 | 44.30 | C40 | 32.63 | 228.00 | 255.00 | 280.00 | 210.00 | 218.00 | 244.00 | 267.00 | 200.00 |
| 300 | 326 | 18.90 | 45.30 | 50.80 | 56.30 | C30 | 43.90 | 290.00 | 323.00 | 357.00 | 282.00 | 278.00 | 309.00 | 340.00 | 269.00 |
| 350 | 378 | 23.70 | 55.90 | 63.20 | 69.60 | C30 | 51.88 | 359.00 | 403.00 | 441.00 | 335.00 | 343.00 | 384.00 | 420.00 | 319.00 |
| 400 | 429 | 29.50 | 67.30 | 75.50 | 83.70 | C30 | 60.78 | 433.00 | 482.00 | 532.00 | 394.00 | 414.00 | 460.00 | 506.00 | 376.00 |
| 450 | 480 | 38.30 | 80.00 | 89.30 | 99.00 | C30 | 73.30 | 515.00 | 575.00 | 632.00 | 472.00 | 492.00 | 550.00 | 597.00 | 450.00 |
| 500 | 532 | 42.80 | 92.80 | 104.30 | 115.60 | C30 | 87.20 | 600.00 | 669.00 | 736.00 | 566.00 | 572.00 | 638.00 | 702.00 | 540.00 |
| 600 | 635 | 59.30 | 122.00 | 137.30 | 152.00 | C30 | 120.62 | 791.00 | 882.00 | 971.00 | 783.00 | 755.00 | 842.00 | 926.00 | 747.00 |
| 700 | 738 | 79.10 | 155.00 | 173.90 | 193.00 | C25 | 142.15 | 1009.00 | 1123.00 | 1237.00 | 932.00 | 963.00 | 1071.00 | 1179.00 | 889.00 |
| 800 | 842 | 102.60 | 192.00 | 215.20 | 239.00 | C25 | 177.07 | 1255.00 | 1394.00 | 1537.00 | 1165.00 | 1197.00 | 1330.00 | 1465.00 | 1112.00 |
| 900 | 945 | 129.60 | 232.00 | 260.20 | 289.00 | C25 | 197.68 | 1521.00 | 1691.00 | 1863.00 | 1446.00 | 1452.00 | 1613.00 | 1777.00 | 1257.00 |
| 1000 | 1048 | 161.30 | 275.00 | 309.30 | 343.20 | C25 | 266.28 | 1811.00 | 2017.00 | 2221.00 | 1759.00 | 1729.00 | 1925.00 | 2118.00 | 1679.00 |
| 1100 | 1152 | 194.70 | 362.80 | 2372.00 | |||||||||||
| 1200 | 1255 | 237.70 | 374.00 | 420.10 | 466.10 | C25 | 373.88 | 2482.00 | 2758.00 | 3034.00 | 2481.00 | 2370.00 | 2632.00 | 2894.00 | 2369.00 |
| 1400 | 1462 | 279.30 | 547.20 | 3563.00 | |||||||||||
ductile iron pipe Mechanical property
| Mechanical Property | |||||||
| Nominal Diameter | Hydraulic test | Tensile strength | Elogation | Yield strength | Bending strength | Brinell hardness | Thickness of cement lining |
| DN(MM) | Mpa | Mpa | % | Mpa | Mpa | HB | mm |
| DN80-DN300 | 5 | ≥420 | ≥10 | ≥300 | ≥590 | ≤230 | 3 |
| DN350-DN600 | 4 | ≥420 | ≥10 | ≥300 | ≥590 | ≤230 | 5 |
| DN700-DN1000 | 3.2 | ≥420 | ≥10 | ≥300 | ≥590 | ≤230 | 6 |
| DN1100-DN1600 | 2.5 | ≥420 | ≥7 | ≥300 | ≥590 | ≤230 | ….. |
