The article describes the use of mulcher technology in forestry for the care of forest crops, removal of overgrowth under power lines, in the right-of-way of gas and oil pipelines, railways and highways. With the help of mulchers, they create fire strips in the forest, make clearings. Mulchers clean fallen trees after fires, floods and hurricanes. They are involved in landscaping and agricultural work. The article examines the work of the PT-400 self-propelled tillage mulcher for the surface crushing of logging waste on the utilized poplar plantations of the Oryakhovsky state forestry in Bulgaria. The work of the Rotor Ferri S stump grinder was studied when crushing poplar stumps with a diameter of up to 50 cm. The hourly productivity of these machines at various operations was determined, and also the process of crushing stumps and felling residues by fractional composition was studied. The work of the mulcher was compared with the bulldozer technology and the mounted tractor stump grinder Rotor Ferri S. It was concluded that the mounted stump grinder Rotor Ferri S is the most suitable machine for grinding poplar stumps of any diameter, since its productivity significantly exceeds that of the PT-400 mulcher/tiller. The load on the tractor is minimal, which saves energy. At the same time, mulching technology is very effective and in demand.

No abstract

At present Russia has adopted a course towards the creation of competitive machinery and equipment. This also applies to mobile manipulator-type forestry machines. Therefore, the design and creation of forestry manipulators with an energy-saving hydraulic drive is an urgent task. The analysis of research of technological, dynamic and kinematic characteristics of manipulator-type machines is given. A new hydrokinematic diagram of the boom lifting mechanism with an energy recuperation system in starting and braking modes is presented. A mathematical model of the boom lifting process has been developed, described by a system of nonlinear differential equations of the second order. Due to nonlinearity, it is impossible to solve the problem in an explicit form; therefore, the finite difference method is used, in which all derivatives are replaced by the corresponding difference analogs. Thus, the original system is reduced to a system of second-order recurrence relations. To solve the relations, the methods of operator theory and functional analysis are used. The sought-for functions are found in the form of a set of points at the nodes of the division of the segment in time. Preliminary calculations using the MathCad program showed that the connection of an energy-saving damping device to the hydraulic drive of the boom lifting mechanism makes it possible to reduce the peak pressure in the hydraulic line of the piston cavity of the hydraulic cylinder during transient modes by 1.5-1.6 times. Bench hydraulic manipulator, made it possible to obtain statistical data on the analysis of the pressure of the system without and with an accumulator, as well as the amount of stored energy per cycle, which amounted to about 30%. The mathematical model of the presented energy-saving hydraulic drive of the forest hydraulic manipulator shows the fundamental possibility of implementing the principle of energy saving during starting and braking modes of loading and unloading operations. Reducing the dynamic loading and energy intensity of the working processes of the boom lifting mechanism of the forestry manipulator by justifying the parameters of the energy-saving damping device of the hydraulic drive allows increasing the reliability of the manipulator, reducing energy costs, as well as the downtime for repairs due to the failure of hydraulic equipment. The results obtained can be used in the design of recuperative systems for other lifting equipment in construction and agriculture