To advance a safer and more sustainable nuclear industry, we offer durable, corrosion-resistant steam generator tube (SGT) compatible with a wide range of reactor types. This includes legacy boiled water reactors (BWRs), modern pressurized water reactors (PWRs) and emerging smaller reactor designs. With an Eddy Current signal-to-noise ratio of 15:1 or better, you can rest easy.
Since 1964, we’ve collaborated with leading utilities and other organizations to drive a safe and reliable road to clean energy production for all of society. As an independent partner, we can effectively navigate geopolitical challenges and nationalistic barriers, allowing us to solve problems quickly for a wide range of reactor types. To date, we have successfully delivered tube bundles to more than 400 steam generators in over 20 countries.
More than 400 tube bundles (approx. 2,600,000 tubes)
supplied to nuclear steam generators in 20 countries.
Integrated, precision manufacturing
To meet your high requirements, we operate one of the world’s largest and most advanced dedicated nuclear tube lines in Sandviken, Sweden. The mill is roughly 340 meters long, and covers 12,000 square meters, or the equivalent of two soccer pitches. Our focus is on premium seamless stainless steel and high nickel alloy steam generator tubing for the world’s toughest industry requirements.
Signal-to-noise ratio of 15:1 or better
The tubes produced at our mill in in Sandviken fulfill the most stringent Eddy Current multifrequency demands and have a signal-to-noise ratio of 15:1 or better. This ensures the absence of any surface or sub-surface flaws and guards against corrosion, deposits or the risk of nickel release.
Key material challenges of SGT
- Stress corrosion cracking (SCC) in high-temperature corrosive environments.
- Corrosion and deposits on the tube, affecting heat transfer and leading to localized corrosion
- Nickel release of ions in the reactor coolant impacting water chemistry controls
Alloy 690 and Alloy 800
Thanks to our fully integrated manufacturing setup, we can maintain very tight quality control – from melt to final tube. Production is focused on steam generator tubing in outer diameters of 10 – 25.4 mm (0.3937 – 1.000"). The main materials are Alloy 690 (Sanicro® 69, UNS: N06690) and Alloy 800 (Sanicro® 30, UNS: N08800), all produced in accordance with ASME and RCC-M standards.
Quality and Sustainable manufacturing
From melt to individual tube, our fully integrated controlled manufacturing process guarantees the highest quality. Beyond meeting all relevant quality standards in nuclear, we are committed to sustainable manufacturing practices. For example, our production in Sweden utlizes 100% fossil-free electricity in, and 83% of our steel is made from recycled materials, embracing a circular approach.
Get an overview of our nuclear solution here
Size range and alloys
The Alleima portfolio includes steam generator tubes in two alloys in size range OD 10-25.4 mm (0.394-1 in.):
| Grade | UNS | RCCM |
|---|---|---|
| Sanicro® 69 | N06690 (Alloy 690) | NC 30FE |
| Sanicro® 30 | N08800 (Alloy 800) | - |
Sanicro® 69
Sanicro® 69 (Alloy 690) is primarily used in nuclear power plants of the pressurized water reactor (PWR) type. For this application Sanicro 69 is used in the 'thermally treated' condition, and is characterized by:
- Extremely high resistance to stress corrosion cracking in PWR primary side water conditions
- Good corrosion resistance in caustic environments
- Good structural stability
- Good weldability
Product standards
- Seamless condenser tubes and heat exchanger tubes: ASTM B 163
Approvals
- ASME Boiler and Pressure Vessel section II ASME SB 163, AFCEN RCCM M4105
