Valmet’s 500th ceramic ValRok press roll coating delivered to Stora Enso’s Oulu Mill
Published Dec 08, 2000 00.00.00 +2 GMT
The 500th Valmet-made ceramic ValRok press roll coating has been delivered to PM7 at Stora Enso’s Oulu Mill. ValRok press roll coatings have been used on the art printing paper machines PM6 and PM7 of the Oulu Mill since 1996. Due to its good runnability properties, ValRok coating works well in the press roll positions of fine paper machines.
The Valmet-developed and patented ValRok roll coating was first introduced in 1991 as an alternative to granite rolls. Ceramic roll coatings have subsequently also replaced polymer coatings at the press section center roll and the fourth press. The special features of ceramic coatings include good web release, cleanliness, doctorability and wear resistance properties. Ceramic-coated rolls have facilitated increased machine speeds at the press section. ValRok rolls have produced several production and 24-hour speed records for various paper grades.
The development of the ValRok S, which is tailored for fine paper grades, started in the mid-90s in cooperation with the Oulu Mill. The mill had decided to invest in a new production line, PM7, that would produce wood-free coated paper, and the line's challenging design speed as well as the novel shoe press application required a new type of cover material for the center roll. The new type of ceramic coating was first tested on Valmet Rautpohja’s pilot machine in 1995-96, after which production-scale test runs were completed on the Oulu Mill’s PM6. ValRok S was taken into use on PM7 in connection with the startup of the machine in 1997. The ValRok coatings have since been used on the press sections of both machines.
Valmet's ceramic press roll coating family currently includes ValRok C and ValRok Ultra NS (newsprint and LWC), ValRok STD and ValRok Ultra (SC grades), and ValRok S for fine paper. Product development currently focuses on mechanical pulp applications. Valmet produces ceramic center roll coatings in Jyväskylä, Finland, Cernay, France, and Aiken, SC in the United States.
Stora Enso Fine Paper’s Oulu Mill is one of the world’s largest and most modern producers of wood-free art printing papers. Its product brands are LumiArt and LumiSilk. The plant facility includes a pulp and paper mill as well as a sheet-cutting plant. The combined annual capacity of the mill's Valmet-made paper making lines PM6 and PM7 totals 800,000 t/a. Fortek Oy takes care of the daily maintenance of the mill.
Valmet, the fiber and paper technology business area of Metso Corporation, is the world’s leading supplier of technology, systems and equipment for the pulp, paper, converting and panelboard industries. In 1999, Valmet’s net sales were EUR 1.7 billion and it had a personnel of 10,600.
Metso Corporation is a global supplier of process industry machinery and systems. Metso’s business areas are fiber and paper technology, automation and control technology, and machinery. In 1999, the net sales of Metso Corporation were EUR 3.4 billion, and the personnel totaled approximately 23,000. Metso Corporation is listed on the Helsinki and New York Stock Exchanges.
Additional Information: Timo S Lintula, Global Product Manager Valmet Corporation, Service Phone +358 20 482 6597 timo.s.lintula@valmet.com
Timo Jortama, Production Manager, PM7 Stora Enso Fine Papers, Oulu Mill Phone +358 2046 124 timo.jortama@storaenso.com
