Class K12 DN1200 ductile iron pipe is engineered for high-pressure water transmission in large-scale applications such as municipal water supply, irrigation, and sewage networks, accommodating trenchless installation methods like HDD and pipe jacking to minimize environmental impact. Manufactured from GGG50 ductile iron, it meets key international standards including ISO 2531, EN 545, and EN 598 for water and sewage applications, ensuring uniform quality and performance. With a robust wall thickness of 19.6 mm, Class K12 pipes deliver exceptional mechanical strength and resistance to external loads, complemented by flange and push-on joints for quick, leak-free assembly. Properly designed and installed systems can achieve service lives exceeding 100 years, supported by cement mortar linings and zinc coatings that prevent internal and external corrosion. Priced competitively at approximately US $320 per meter FOB China, Class K12 DN1200 offers excellent value against alternative pipe classes and materials.
Application Scenarios
Municipal Water & Sewage Networks
Class K12 DN1200 pipes are ideal for main trunk lines in urban water distribution and sewage collection systems – handling high flow rates and pressures reliably for decades.
Irrigation & Water Conservancy
Suited for long-distance raw water conveyance, reservoirs, rivers, hydraulic hubs, and agricultural irrigation pipelines, these pipes support large volumes under variable terrain and environmental conditions.
Trenchless Construction
Designed for HDD (horizontal directional drilling) up to DN 1000 and pipe jacking for DN > 1000, enabling installation beneath roads, rivers, and sensitive sites without open-cut excavation.
Industrial & Building Services
Used extensively in industrial parks, enterprise facilities, and building water/sewage systems, Class K12 DN1200 provides robustness against mechanical loads, vibration, and pressure surges.
Special Applications
Also applied in heating systems (EAHE), trenchless jacking, and anchor-type installations where angular deflection and joint flexibility are critical.
Lifespan
Modern ductile iron pipe is proven to exceed 100 years under normal design and soil conditions, earning recognition by the DIPRA Century Club for service over a century. Zinc-coated variants leverage sacrificial anode protection to ensure life expectancy of at least 100 years, compared to 50–75 years for uncoated pipes. Advanced cement mortar and specialized linings (e.g., calcium aluminate for aggressive media) virtually eliminate internal corrosion, securing structural integrity over the long term.
Installation and Connection
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Joint Types: Push-on Tyton (T-type), K-type, mechanical restrained, and ANSI/B16.1 or ISO 2531 flanged connections allow quick, leak-free assembly with minimal tooling.
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Open-Trench & Trenchless Methods: Standard open-cut installation follows DIPRA/AWWA guidelines (e.g., A21.51), while HDD and pipe jacking (PJ) methods facilitate minimal-impact laying in urban and sensitive environments.
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Gasket & Sealing: EPDM/SBR gaskets meet ISO 4633, installed with lubricant for secure sealing; flanged joints use tapped flanges fabricated to ISO 2531 wall-thickness requirements.
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Angular Deflection: Socket-spigot and restrained joints support deflection angles to accommodate alignment corrections without additional fittings .
International Standards
Class K12 DN1200 pipe complies with:
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ISO 2531 / EN 545 for potable water applications.
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ISO 7186 / EN 598 for sewerage pipelines.
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YB/T 4564 / ISO 13470 specific to trenchless jacking applications.
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ISO 4179 / ISO 8179 governing cement mortar lining and zinc coating performance.
Other Series Price Comparison
| Class | Wall Thickness (mm) | Price per Ton (USD, FOB China) | Price per Meter (USD) |
|---|---|---|---|
| K7 | 9.8 | 700–900 | – |
| K8 | 13.6 | 800–1200 | – |
| K9 | 14.8 | 470–570 | – |
| K12 | 19.6 | – | 320 |
Advantages
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High Mechanical Strength: Excellent resistance to internal pressure (≥ 3 × PFA) and external loads like ground settlement and traffic.
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Long Service Life: 100+ years proven performance with minimal maintenance.
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Superior Corrosion Resistance: Zinc/aluminum coatings and loose polyethylene sleeving as needed.
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Leak-Free Joints: Tyton and flanged connections deliver reliable sealing under dynamic conditions.
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Flexible Installation: Socket deflection reduces need for bends, accelerates pipeline layout.
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Environmental Sustainability: High recycled content, fully recyclable at end-of-life, and low life-cycle cost.
Frequently Asked Questions
Q1: What defines Class K12?
A: Wall thickness of 19.6 mm, designed for PN 25–40 applications requiring high structural performance.
Q2: Which standards apply?
A: ISO 2531/EN 545 for water; ISO 7186/EN 598 for sewage; ISO 13470 for trenchless jacking.
Q3: How long will it last?
A: Service life typically exceeds 100 years with proper linings and coatings.
Q4: What installation methods are supported?
A: Open-cut, HDD, and pipe jacking with push-on or flanged joints; gaskets per ISO 4633.
Q5: How does Class K12 compare cost-wise?
A: At ~$320/m, it competes favorably against thinner classes and alternative materials when life-cycle cost is considered.
Case Studies
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Mega Reservoirs Project, Doha (KAHRAMAA): T-type DN 1200–1600 cement-lined and zinc/bitumen-coated pipes store 7 days of potable water in single/multiple lines.
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Greece Water Supply Project: DN 1100–1200 ductile iron mains installed by Jigang Cast Pipe under ISO 2531 standards serve municipal networks, demonstrating adaptability in diverse terrain.
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 | ….. |
