A partnership forged between Primetals Technologies and Italys Arvedi Steel is revolutionizing the production of ultra-thin, hot-rolled strip by bypassing the traditional casting-rolling sequence and has earned Primetals Technologies AMMs 2017 Steel Excellence Award for Technology Provider of the Year.
The innovative technology provided by Primetals Technologies permits the production of hot-rolled coils directly from liquid steel in a continuous process. The process flow begins with the casting of a thin strand of steel that is subsequently rolled to an intermediate thickness of 10- to 20 mm in a three-stand, high-reduction mill located at the end of the caster. After reheating in an induction heater, the transfer bar is rolled to the targeted thickness of 0.8- to 12.7 mm on a five-high mill followed by laminar strip cooling. A high-speed shear cuts the strip immediately before cooling of coils weighing up to 32 tonnes.
It is a great honor to be named Technology Provider of the Year, Satoru Iijima, president and chief executive officer of Primetals Technologies USA LLC, said upon accepting the Award. We are proud that Arvedi ESP is being recognized as a provider of game-changing technology for the steel industry.
Our nomination was based on the great operational results of three Endless Strip Production (ESP) plants at Rizhao (Chinas Rizhao Steel Group Co. Ltd.), he noted. Our customer is very pleased with the performance of the plants and we expect to achieve similar results from two more Arvedi ESP plants that we are now commissioning.
In conventional steel production, slabs are cast on a continuous caster and then cooled to ambient temperature or directly charged for reheating and separate rolling. Although other plant builders have improved upon this sequence by combining thin-slab casting and rolling facilities, such advances are essentially incremental in nature and continue to involve slab-by-slab rolling.
Based on the operational experience and development of Arvedi Steel owner Giovanni Arvedi, who also serves as chairman, Primetals Technologies designed and built the first ESP line at Arvedi Steel in Cremona, Italy. The initial Arvedi ESP line was designed and developed over a period of three years and began operations in 2009.
Today, hot-rolled strip can be produced uninterrupted with equal geometrical and metallurgical properties from head to tail. Arvedi ESP can also produce the best surface quality on thicknesses down to 0.8 mm, allowing steel producers to even eliminate the need for cold rolling. If cold rolling is desired, thinner gauges than usual can be obtained with fewer rolling stands because the incoming material is already significantly thinner than usual.
The Arvedi ESP technology offers users a number of advantages. Counted among them are:
A lower investment cost thanks to a reduction in the required length of the plant (180 meters versus 450 meters for conventional plants).
Lowest cost operation/conversation costs due to less alloying, a yield of 98 percent, more stable operating conditions, significantly less scale formation on the strip and lower energy consumption and emissions compared to the conventional process.
Highest profit potential achieved through producing ultra-thin, hot-rolled strip at full width and full productivity featuring uniform strip quality and capable of delivering certified API pipe grades and excellent surface quality.
Hot-rolled coils coming off the ESP lines go directly to annealing and galvanizing lines without requiring cold rolling. The product is then sold directly as cold-rolled substrate.
For API and HSLA grades, the use of alloying elements in the melt shop can be reduced because the ESP process operates for hours at stable speeds within greater rolling temperature predictions.
The Arvedi ESP lines at the Rizhao plant have notched several milestones, including producing the highest volume of thin-gauge material. Some 50-percent of the sequences cast on the ESP lines there produce strip measuring below 1mm with a six-month average below 1.2 mm and 84 percent of the material cast measuring less than 2-mm thick. Rizhao has also recorded the lowest energy consumption and benefitted from more stable operating conditions.
Worldwide, Primetals Technologies is the sole licensee of Arvedi ESP and the only company permitted to sell the patent-protected technology. With the success experienced at Rizhao and at its flagship plant in Chinas Shandong Province, Primetals Technologies is eying the rest of the world as a stage on which to achieve similar results .
A signed contract for the next ESP line specifies the most powerful ESP line ever to be built, featuring endless operation for thicker gauges and higher capacity. This line will be installed in the Middle East. Additional letters of interest have been signed in well-known, steel producing countries.