Två nya trailerkoncept för transport av rundvirke hos Stora Enso : en analys av prestation och flexibilitet

Sammanfattning: The need for roundwood transport capacity vary throughout the year. The need during a period is influenced mainly by the volume transported the period, the number of days during which transport can be carried out, seasonal variations in road conditions and the weight of the roundwood, and the origin of the wood (private forest owners/ forest companies). The need for transport capacity generally increase during the winter and in spring, after thawing. Lack of logging trucks combined with a lack of drivers for these trucks make it hard to hire extra help during periods of increased transport capacity needs. It is also very expensive to keep logging trucks for use only during these periods. In this thesis, two new concepts based on the partial transport by truck tractors have been examined, to find out the possibility for increased performance and flexibility. Concept 1 uses load exchange sites as the breaking point between logging trucks and truck tractors. The roundwood transport from the forest to the load exchange site uses logging trucks with attached dollys and semitrailers. At the load exchange site, the wood pile on the logging truck is reloaded to a link, which is then connected to the semitrailer. The link and semitrailer are then transported to the paper, pulp or sawmill using a truck tractor. Concept 2 uses an ordinary terminal as the breaking point, and roundwood transport from forest to terminal is carried out by regular logging trucks, which drop off the entire load at the terminal. Transport from terminal to industry is carried out by truck tractors and semitrailer. Two different models were designed. Both were based on balancing the ingoing and outgoing wood flows to the load exchange site or terminal, to avoid any increase or decrease of stock in the terminal or to create a stock at the load exchange site. In concept 1 the waiting periods were limited to a maximum of 10 minutes.Both models could be applied, using combinations of 1-3 logging trucks and 1-3 truck tractors. At system level there were 12 logging trucks available. For concept 1 a doubling of flexibility is possible to manage. For concept 2 there can be an increase of flexibility by one fifth. However, for Concept 1, the minimization of waiting periods leads to restrictions in possible distances from forest to load exchange sites. Transport planning will also be affected by Concept 1, since the fitting loading sites must be chosen several weeks in advance. Concept 2, on the other hand, will not alter transport planning much, as it quite similar to traditional use of terminals.