Courtesy of Tubacex and Outokumpu
Production of high temperature seamless tubes is very demanding. Necessary for use in numerous applications, from furnace technology and energy conversion plants to power plants and metalworking, high temperature stainless steel grades need to have high levels of strength and resistance due to their exposure to highly corrosive and oxidizing conditions.
That’s why Outokumpu partnered with Tubacex, a global leading stainless steel and high nickel alloys tubular solutions supplier. In the collaboration, Tubacex used Outokumpu Therma 253 MA billets as starting material for the production of seamless tubes optimized for very high service temperatures.
Developed by Outokumpu, Therma 253 MA (1.4835/S30815) is an austenitic stainless steel grade. It provides an excellent oxidation and creep resistance in cyclic conditions that is best employed in very high temperatures. The grade also presents excellent mechanical strength at high temperatures.
Says Diego Herrero, Tubacex Innovation and Technology Corporate Director: “We are very pleased with the cooperation with Outokumpu. Tubes of the new grade have been successfully produced and have favourably passed extensive laboratory tests. Our tubes provide excellent cyclic oxidation response at high temperature as well as very good mechanical and corrosion properties. These characteristics are needed in aggressive environments such as production of carbon black.”
“Outokumpu Therma 253 MA grade can give you a longer product lifecycle compared to alternative grades. MA grades have significantly higher mechanical strength at high service temperatures. This means you can use thinner gauges, increase efficiency and reduce material costs, or use the same thickness with higher loads to increase productivity,” says Olle Källgren from Outokumpu Long Products.
Through the tests
These stainless steel tubes respond to the need for corrosion resistant material for use in high-temperature applications like furnaces or in steel or ironworks. A material’s resistance to high-temperature corrosion is in many cases dependent on its ability to form a protective oxide layer. The Outokumpu material fulfilled the tough requirements of oxidation and erosion-corrosion resistance up to 1,150 degrees Celsius.
The tubes created by Tubacex using Outokumpu Therma 253 MA approvingly passed large-scale laboratory tests. They provide excellent cyclic oxidation response at high temperatures and very good mechanical and corrosion properties, which are needed in aggressive environments such as production of carbon black.