System analysis of the wheel forwarder’s technological efficiency on the unloading operation
System analysis allows you to build a single functional space - the time of production operations for different levels of connectivity of technological processes. The Scandinavian technology is based on a complex of «harvester + forwarder» machines connected by a production cycle. Modern harvester are mainly single-module (single-grip): all operations (felling wood, pruning branches, bucking and measuring, sub-sorting) are performed with a single harvester head located at the end of the manipulator. Tree felling begins with bringing the felling head to the tree, medium trees are felled with one cut. When cutting down the main use, the fellingremains are put on a skidding road under the machine. Under the new trend, felling residues are collected for the production of fuel wood. For harvester, we note the following four phases (sub-operations) of work: 1 - moving from one Parking lot to another, 2 - bringing the felling head to the tree, cutting and felling, 3 - delimbing and bucking, 4 - sub-sorting. In the second phase of operation, the cutting time and volume of wood determine the productivity of tree production. In the third phase, the time of cutting branches and their volume determine the production capacity of secondary raw materials; the bucking time and the amount of sorting determine the productivity of sorting production. Thus, the work of the felling head can be considered forwarder a two-step process, as a system of sub-operations associatedwith a single functional time of production of a unit of labor (1 m3 of wood material).This total functional time ultimately determines the productivity of secondary raw material production and sorting for each tree. In the «harvester+forwarder» cycle, the production capacity of wood material from each tree is determined based on the total functional time: the working time of the felling head and the waiting time for the selection of wood from the forwarder. A systematic approach to evaluating the technological efficiency of forestry machines in the cycle of their connectivity provides a more informative picture of the dynamics of connectivity of production processes as a single space-time structure. This makes it possible to formulate technological efficiency more objectively.