Estimation of the load capacity and the strain-stress state of rod transporters

Abstract

In the paper, an analytical study of the stress-strain state of the structural system of the rod conveyor of root harvesting machine with the maximum load arbitrarily distributed on the conveyor belt is performed. Rod conveyors are one of the main nodes for transporting and separating root crops through the technological channel of root harvesting machines, for loading them into a hopper and onto a vehicle. Structurally, they form an endless grid that surrounds the leading and driven sprockets or pulleys and supporting rollers. The entire structure of the conveyor is attached to the frame, which rests on the main frame of the harvesting unit. The shape and parameters of the rod conveyor are chosen depending on the layout of the unit and the required performance. Reasons for wear and failure of rod conveyors: deviation of the belt during operation, intensive wear of the holding elements in the places of their attachment to the traction elements and the traction elements themselves. It was found that the degree of wear of the left and right runs is different, as a confirmation of the unevenness of the load on the belt during operation. The uneven load of the conveyor is caused both by the transported pile of root crops and by the design features of the conveyor itself, in particular, uneven tension of runs, deviations during installation of shafts, installation of sprockets or pulleys, support rollers, etc. External loads acting on structural elements of agricultural machines are variable quantities. This should be taken into account when determining the stress-strain state of structures. It is possible to estimate the stress-strain state of complex structures of root-harvesting machines, their elements, and search for their optimal parameters, provided that the force factors in the sections of the elements are determined under full stress. In this way, it is possible to optimise the designs of such machines in terms of material consumption and work resource. The proposed method makes it possible to estimate the stress-strain state of rod conveyor elements according to operating conditions and the possible ways of their further improvement.