Computer simulations of the process of folding and unfolding of main frame of agricultural implement which were carried out and the phase of designing are discussed in the paper. Elaborated geometrical model of the mainframe was put to the analysis to determine the influence of implement position changes on reactions in the points of its mounting on the tractor as well as to determine the influence of changes of positions of the frame side arms on reactions in the points where hydraulic cylinders are fixed. Then the location and shape of the stops and the connecting rod were determined. As a result of these works created was construction of the agricultural implement main beam which will be a base for carrying out strength analysis of calculation model FEM of the whole construction of the agricultural multifunctional implement.