Mathematical description and physics of the process of splitting round timber
Wood splitting is widely used in the forest industry for the complex use of wood, including for the production of chips from pulpwood and low-quality roundwood. The article presents information on the properties of wood, which allows splitting round timber along the fibers. Various forms of cleavers for splitting logs into two, four, six or more parts are given, depending on the requirements of production. The forces acting on the wood during the introduction of the cleaver and leading to the splitting of the log are considered. Formulas are given for calculating the vertical and horizontal components of these forces, the friction angle, the wedge coefficient and the friction coefficient, which make it possible to calculate the indicators of the splitting process. Studies of the process have shown that the splitting forces depend on the properties of the wood, including the type of wood, its structure, humidity, temperature, and dimensions. Numerical coefficients are calculated that take into account the state of wood, and the parameters of specific splitting resistance are determined depending on the position of the wedge relative to the wood fibers. Formulas are given for calculating the magnitude of the wedge stroke, leading to the splitting of a log, especially logs 1.0-1.5 m long. The designs of industrial splitters are considered and the calculation of the drive power of a chain splitter that splits a log 1.0 m long into two parts is given. At the same time, the speed of movement of the chain (stop) pushing the log onto the cleaver was calculated. The article presents diagrams of wedges of cleavers, diagrams of industrial cleavers, and a graph of the force on the wedge, leading to splitting of the log. The above graph shows that the splitting process takes 0.4 seconds, and the rest of the time 0.5-2 seconds is spent on the collapse of the log parts along its length.