Pressure determination of special earthmoving machines on the ground in working and transport mode

Summary. Raising of problem. The working equipment of three of the four special earthmoving machines for main pipelines major overhaul must be installed on a specialized crawler chassis Class 15 tf. The nature of work of each of these machines has its own characteristics, which consequently reflects on the loading of the chassis elements, especially on its moving equipment. Thus the machines MPRG and MVT during work under the action of gravity and the force components of soil excavation have the resultant of total forces that moves back (closer to the rear of the vehicle). This leads to a shift of the pressure center toward the chassis drive wheels, as a consequence, to increase the maximum pressure on the ground. In the process of soil compaction under the pipe on the ground crimping blades of the sealing mechanism there is the vertical component of ground resistivity which leads to a redistribution of vertical reactions on caterpillars. As a result, the inner caterpillar is loaded almost to zero. Moreover, there are vario us traction forces on each of the caterpillars during the operation of the machine. In order to select rational parameters of unified tracked chassis satisfying requirements of technological processes performed by machines MPRG, MVT and MT for which it is the base it is necessary to determine load on each caterpillar of the chassis, tractive force in caterpillars, the value of the total vertical resultant vector of the external forces, that act on the machine, maximum pressure value of the caterpillars on the ground and the center of its applications. It allows to substantiate the parameters of the support chassis circuit, its configuration, parameters of counterweight and drive design requirements.