Tenaris invested more than $10M in developing Thor® 115 in 2018, a new steel alloy for tubulars with improved resistance to steam oxidation, longer material life and superior creep behavior. Antonella Ferrara, product senior manager for Tenaris’s power generation segment, and her team presented two technical papers related to the use of Thor®115 in industrial applications at the 5th International ECCC Creep & Fracture Conference 2021 held this October. In the following Q&A, Ferrara talks about the results of the first industrial testing of Thor®115 used in manufacturing boilers and the benefits for customers.
What makes Thor®115 a unique solution for the power generation segment?
Thor®115 is a ferritic steel designed by Tenaris for advanced power generation plants with a chromium content of 11%. Its use allows the production of steam at higher temperatures than the ones allowed by traditional steels with chromium content up to 9% and is used as an alternative to stainless steel, for example in new generation plants under construction in Italy, or in replacement of the grade 92. Stainless steels in fact present mechanisms of degradation and management problems during operation under high cyclical conditions, while the grade 92 is not a damage tolerant material. Both stainless steel and grade 92 require greater management during the welding phase, which are not required when welding Thor®115 as its more robust.
What projects has Thor®115 been used in so far?
In Italy, boilers have been built for the Edison power plants in Marghera and Presenzano, and in the Tavazzano, using Thor®115. Abroad, Thor® 115 has been used in the Termocandelaria plants in Colombia and in Fujairah in the Middle East. The use of Thor®115 in these projects enables the power plants to increase efficiency while reducing CO2 emissions.
Can you explain what kind of research is behind the recent technical papers presented and its results?
The big result is that we have moved from the research and development phase of a material to studying its concrete application. It is no longer a matter of carrying out laboratory tests from which we were able to draw indirect measurements of the behavior of the material in operation. A first phase of pre-production tests was followed by a second phase in our creep laboratories that confirmed the damage tolerant behaviour or ductility of the Thor®115.
What does this activity indicate?
Today, we can say that, thanks to the solidity of this study, the use of Thor® 115 allows us to predict the evolution of the material over time, its geometric deformation and any signs of breakage.This is valuable information for the predictive maintenance of a plant.
To learn more about Tenaris solutions for power generation visit our product page.