July 31, 2009
TEMPALOY AA-1 is a practical, austenitic stainless steel that is currently used in high-temperature and high-pressure areas in superheater and reheater sections of coal thermal power plants. These plants typically operate at steam temperatures above 600° Celsius. In the future, Tenaris intends to supply this product to be used at plants operating at steam temperatures exceeding 650° Celsius and Pressures of 25MPa.
The higher steam temperature will generate higher power more efficiently. According to an estimate by the Agency for Natural Resources and Energy in Japan, just a 5% increase in generating power more efficiently in thermal power plants will reduce CO2 emissions by approximately 3 percent.
"Our high-strength, stainless TEMPALOY AA-1 tubes for thermal power plants will be an integral product for building next-generation thermal power plants,” said Yusuke Minami, Chief Researcher, R&D, TenarisNKKTubes, one of the team members engaged in developing TEMPALOY AA-1.
In general, boilers must be stable for operating over 20 years or even longer and they must be cost effective as well. TEMPALOY AA-1 (18Cr-10Ni-3Cu-Ti-Nb) high-strength steel can satisfy all of these requirements. In addition, TenarisNKKTubes has developed a shot-blast technology to process the internal surface. This enhances the oxidation resistance against steam inside of tubes.
TEMPALOY AA-1 has already received approval from the American Society of Mechanical Engineers (ASME) and the American Society for Testing and Materials (ASTM). 2009).
Tatuo Ono, R&D Director TenarisNKKTubes, commented: "Global environmental protection is one of the most important issues in the world. Our TEMPALOY AA-1 perfectly matches this issue. To meet broader customer needs, we can supply a wide product line as a single package for boiler tubes, from high-quality carbon steel to 9Cr alloy steel, as well as AA-1 products of austenite stainless steel."