Marcus Wallenberg Prize of 2 million Swedish Crowns awarded to three Valmet engineers
Published Oct 11, 1999 00.00.00 +2 GMT
On October 7, H.M. King Carl XVI Gustaf presented the 16th Marcus Wallenberg Prize to Pekka Eskelinen, Raimo Virta and Vesa Vuorinen. They were awarded for a path-breaking development of the papermaking technology.
They received the Prize for their development of a unique technology used at the drying of the paper web on papermaking machines, which has enabled productivity increase of more than 20 per cent. In combination with other measures even substantially higher raises of the efficiency have been gained. This means a corresponding increase of the return on the invested capital. This technology has been taken into use on a large number of paper machines in many countries.
The prize amount is shared equally between them.
The Prize-Winners worked for many years at Valmet Corporation, The Pansio Works, where the technology was developed.
Mr. Pekka Eskelinen, M.Sc., was born in 1952. He is now Regional Manager for Jaakko Pöyry Engineering Oyj in Kouvola, Finland. Mr. Raimo Virta, B.Sc., was born in 1940. He is retired and lives in Turku, Finland. Mr. Vesa Vuorinen, B.Sc., was born in 1936. He is now R&D Engineer at the Valmet Pansio Works in Turku, Finland.
The motivation by the Prize Selection Committee says: They are awarded the sixteenth Marcus Wallenberg Prize for their path-breaking development of a unique air blowing technology for stabilizing paper webs aerodynamically at high paper machine speeds. This development has been taken into use on a large number of paper machines in many countries and has lowered the costs of paper production by greatly increasing the speed and efficiency at which papermaking machines can be operated.
The capital invested in a large fast running paper machine often amounts to billions of Swedish Crowns. To increase the productivity by some ten-twenty per cent by means of the awarded technology raises the profitability of the investment considerably. Commercially it has been and still is a success.
The drying of the paper sheet or web on a paper machine takes place in the dryer section, where the web runs in contact with a number of steam heated cylinders. Thus the web is heated and the water in it is evaporated. In the dryer section of a fast running paper machine the paper web is supported by a fabric.
Fast moving surfaces drag air along with them. The air nearest to the surface moves almost as fast as the surface itself. These boundary layers of air produce an overpressure in the closing nips that are formed between the cylinder and the fabric approaching the cylinder. This overpressure and air turbulence tend to blow the web away from the fabric. The result is that the web flutters and often breaks, which causes production losses and reduces the operating efficiency of the paper machine.
Eskelinen, Virta and Vuorinen have identified the cause of this problem and developed a unique air blowing technology, that makes it possible to avoid overpressure and air turbulence in the nip and thus eliminate the problem. It is done by means of a specially designed blow box, that blows air from the nip against the running direction of the fabric and the cylinder, preventing the air that is dragged by the fabric from flowing into the nip. Simultaneously, to keep the web firmly attached to the fabric a sufficient underpressure is created without the blow box being in contact with the web or the fabric. The basis for this technology is since long known aerodynamic laws, which have been applied in a unique way.
This blow box technology has enabled a substantial increase of productivity and efficiency of papermaking machines and more than 10,000 blow boxes of this design have been installed. It has contributed significantly to the reduction of costs for the manufacturing of several important paper grades, which are now produced at speeds between 1200 and 1700 m/minute.