Kartläggning av ruttplaneringsprocesser för rundvirkestransportörer
Transportation represents 10-15 % of wood supply costs. It is therefore important to improve efficiency in the transport system to decrease these costs. The aim of this study is to map the timber vehicle routing processes used by a sample of timber hauling contractors and to identify possible links between the vehicle routing process and service and economic variables. The study was carried out at Södra Skog in autumn 2008. 15 timber hauling contractors were sampled and interviewed about their work with timber transports. A base model for a timber vehicle routing process was mapped. The main steps in the timber vehicle routing process were: Data collection - Trucking company receives transport orders and information from transport administratorsPreparatory planning - The trucking company prepares an overview of possible transport routesMain planning decisions - The trucking company takes into consideration the factors that restrict the execution Resource allocation ? The trucking company takes into consideration the factors that determine the coordination of labour. The main variants of the base model were also mapped and compared with respect to their service and economic variables. The two most significant deviations from the base model concern the occurrence of follow-up of delivery quotas in Preparatory planning and certain combinations of activities in Main planning decisions. In the results of this study increasing service levels are negatively related to profitability. Follow-up of delivery quotas is linked to increasing service level but negatively related to profitability. This is because Follow-up of delivery quotas directs the trucking company to specific landings and (hence) restricts the routing planning. In Main planning decisions there are restrictions such as availability and the volumes of the landings. Inclusion of these restrictions in routing is linked to both higher service levels and profitability. Profitability is also affected by how many hours each lorry is used per year. Higher capacity utilization than 4000 hrs/yr per truck is linked to lower profitability.