With their characteristic yellow sheathing and bundles of steel tubes, fibers and cables, umbilicals are vital links between subsea wellheads and infrastructure. At the core of their functionality is our portfolio of super-duplex stainless tubes – the industry’s workhorse – delivering high strength, lighter designs and exceptional resistance to harsh environments.
SAF™ 2507 – Pioneers in duplex steel
One key metallurgical milestone was our early development of duplex stainless steel materials in the mid 1990s. These 50-50 ferritic-austenitic steels offered superior strength and fatigue properties compared with standard stainless steels, while enabling thinner walls and lighter designs. One such grade, the super-duplex seamless stainless steel, SAF 2507 (UNS S32750), soon became the industry standard – and remains a workhorse today for umbilical tube.
SAF™ 3007 – the next generation duplex
Today, with ongoing demand for safe, lighter and more efficient designs, we are taking the next step by developing a new alloy: SAF™ 3007. Thanks to its evolved microstructure, it delivers even higher fatigue strength – enabling lighter, more optimized design and lower cost per kilo.
160,000,000 meters delivered
Today, we are a market leader in stainless steel umbilical tubing, having supplied more than 160 million meters (525 million feet) to all major fabricators – equal to circling the world three times. In the process, we’ve teamed up closely with most all leading oil and gas companies in the offshore regions. Every order is produced in a highly controlled, integrated mill from a single melt.
Your subsea lifeline
Naturally, all subsea infrastructure is important, but umbilicals are especially critical in ensuring the reliability and safety of offshore oil and gas operations. Made with high-performance super-duplex stainless steel, these small-diameter tubes (encased in the yellow outer sheath) transport fluids, chemicals, and gases while enabling remote monitoring and control of underwater infrastructure.
Bundled with cables and fibers, they form a robust umbilical system – you might say “the lifeline” of subsea operations. Designed to endure extreme pressures, corrosive seawater, and deepwater stresses, these tubes ensure seamless operation of subsea equipment.
Two main types
- Dynamic umbilicals: Designed to withstand movement, swaying, and twisting in water, often connecting floating platforms or spars to the ocean floor.
- Static umbilicals: Installed in fixed positions on the ocean floor or onshore, providing stable connections for power, control, and communication.
Key challenges / benefits
- Corrosion resistance: Withstanding harsh seawater and high-chloride marine environments.
- Mechanical strength: Enduring stress from system pressure, long lengths, dynamic movement.
- Chemical compatibility: Injecting methanol, corrosion and scale inhibitors and other chemicals.
- Signal and power transmission: Safely housing fiber optics and electrical conductors, etc.
- Hydraulic fluid transmission: Delivering fluids under high pressure for subsea control systems.
- Weight and cost efficiency: Using stronger material with thinner walls for lighter, cost-efficient reel handling(and lower cost per meter)
- Fatigue resistance: Ensuring durability under repetitive loading and motion in dynamic environments.
- Thermal performance: Managing temperature variations to ensure consistent operation.
Fully integrated production
Alleima ensures the highest quality by manufacturing all products, including super-duplex tubing for subsea umbilicals, in a fully integrated process. Starting with a single melt of 80% recycled steel in Sandviken, Sweden, every step is carefully controlled up to the final tube.
Dedicated umbilical tube mill
Our state-of-the-art mill in Chumutov, Czech Republic, near Prague, is dedicated to umbilical tubing. Here we conduct extensive quality control, including both destructive and nondestructive testing, with X-ray inspection of every orbital weld. All tests are fully traceable and meticulously documented to provide our customers with complete confidence.
We’d love to hear from you!
If you have question, don’t hesitate to give our umbilical team a call or shoot us an email. We’d love to hear from you. You’ll find our main grades below.
Coiled tubing for cost-effective umbilical manufacturing
Alleima offers orbital-welded coiled tubing for cost-effective umbilical manufacturing. Our umbilical tubes are also offered in straight lengths, as long as 40 meters (131 feet), for a minimum requirement of orbital welds.
Umbilical tube materials
| SAF™ 2507 (UNS S32750) |
|---|
| A super-duplex stainless steel that combines high corrosion resistance and high mechanical strength. With excellent resistance to seawater and marine environments, it is particularly well-suited for applications exposed to high stress in aggressive chloride-rich environments. The resistance to sour environments is superior to SAF™ 2205 (UNS S31803/S32205). PRE value min. 42.5 (valid for tube and pipe). Read more about SAF 2507® |
| SAF™ 3007 (UNS S83072) |
|---|
| SAF™ 3007 is a super-duplex (austenitic-ferritic) stainless steel optimized for service in highly corrosive chloride environments where a high strength material is required. The new tube offers a safe, lighter, stronger and more efficient alternative to SAF™ 2507, the current industry standard. Read more about SAF™ 3007 |
Size range
| Inner diameter | Wall thickness (mm) | ||
|---|---|---|---|
| in. | mm | min | max |
| 3/8 | 9.53 | 1.2 | 2 |
| 1/2 | 12.70 | 1 | 2.6 |
| 5/8 | 15.88 | 1 | 3 |
| 3/4 | 19.05 | 1.1 | 4 |
| 1 | 25.40 | 1.3 | 5 |
| 1¼ | 31.75 | 1.5 | 5 |
| 1½ | 38.10 | 2 | 5 |
| 1¾ | 44.45 | 2.5 | 5.5 1) |
| 2 |
50.80 | 2.7 | 6 1) |
1) Specific NDT acceptance criteria are applied for these dimensions
| Inner diameter | Wall thickness (mm) | ||
|---|---|---|---|
| in. | mm | min | max |
| 1¾ | 44.45 | 2.50 | 8.00 |
| 2 | 50.80 | 2.80 | 8.00 |
| 2¼ | 57.15 | 3.20 | 9.00 |
| 2½ | 63.50 | 3.50 | 8.00 |
| 2¾ | 69.85 | 4.00 | 8.00 |
| 3 | 76.20 | 4.30 | 10.00 |
| 3¼ | 82.55 | 4.60 | 8.00 |
| 3½ | 88.90 | 4.90 | 12.00 |
| 3¾ | 95.25 | 5.30 | 9.00 |
| 4 | 101.60 | 5.50 | 14.00 |
| 4½ | 114.30 | 6.30 | 16.00 |
| 5 | 127.00 | 7.00 | 18.00 |