Offshore Marine Pipelines
Subsea pipeline systems engineered for offshore oil & gas platforms and marine infrastructure projects.
Overview
JO STEEL supplies offshore-grade steel pipes for subsea pipeline installations, platform risers, and marine infrastructure. Our offshore pipes meet DNV-OS-F101 and API 5L PSL 2 specifications, with concrete weight coating (CWC), corrosion-resistant alloys (CRA), and full subsea qualification documentation.
The Challenge
Offshore and subsea pipelines must withstand extreme hydrostatic pressure, seawater corrosion, dynamic loading, and installation stresses during S-lay, J-lay, or reel-lay operations—all while maintaining long-term structural integrity.
Our Solution
We provide offshore pipeline systems with factory-applied concrete weight coating, 3-layer polyethylene (3LPE) or polypropylene (3LPP) anti-corrosion coating, and optional CRA cladding or lined pipe for high H2S / CO2 environments. Full DNV, ABS, or Lloyd's certification available.
Key Features & Capabilities
- DNV-OS-F101 and API 5L X52 through X80 offshore grades
- Concrete weight coating (CWC) for negative buoyancy
- 3LPE / 3LPP external anti-corrosion coating systems
- CRA-lined or clad pipe for sour service (Inconel, 316L, 2507)
- Subsea installation support: bevel inspection, hydrotesting, documentation
- Full material traceability and third-party witness testing
Typical Products Supplied
- API 5L X65 / X70 offshore line pipe with 3LPE coating
- Concrete weight-coated subsea pipeline (12" – 48")
- CRA-lined sour service pipe (Inconel 625 / 2507 Duplex)
- Platform riser pipe with connection flanges
- Flexible flowline and umbilical support structures
Standards & Compliance
Case Study
| Project | Offshore Gas Export Pipeline |
|---|---|
| Location | Mediterranean Sea |
| Scope | 24" X65 PSL 2 with CWC and 3LPE, 65 km subsea |
| Delivered | 9,800 tons with DNV witnessing and pipelay support |