For new designs of mine hoisting machines, the development of scientifically-based solutions to increase the rope capacity and reduce the size of the machines is relevant. Based on the theory of laying the rope on a lined cylindrical drum developed by the authors, it is shown that when choosing a groove profile and winding pitch for a non-lined drum, it is necessary to use a geometric rope laying model, and for taking into account the elastic lining, it is necessary to use a physical model of static interaction of a rope with a scallop of the groove. It is recommended to use the U-tilda-groove profile, which will allow a 4.5 % increase in the drum capacity while maintaining the rope’s curvature radius that is permissible under safety rules during its installation.
Purpose. Development of a mathematical model of the stress-strain state of the body of the winding of the bobbin hoisting machine with rubber-rope cable.Methodology. Methods of mathematical and computational experiment based on the finite element analysis are used.findings. To solve the problem of defining the torsional stiffness of the body of the winding of the rubber-rope cable (RRC), the physical model of the body of the winding was represented in the form of a composite in which the reinforcement is an infinitely thin spiral having stiffness characteristics of a metal rope and the matrix is a rubber sheath. After processing the results of the computational experiment using the computer finite element modeling method, an analytical expression for determining the torsional stiffness coefficient of the body of the winding of the RRC was obtained, the analysis of which shows that the stiffness of the body of the winding depends quadratically on its outer diameter, and the local stiffness depends little on the diameter. The danger of dynamic effects occurring in the bobbin hoist can take place at a large number of turns in the winding.Originality. The regularities of the influence of the rubber-rope cable parameters on the torsional stiffness of the body of the winding have been established. The nonlinear character of changing the given stiffness characteristics of the RRC packet layers is caused by the peculiarity of interaction of the first packet layer with the bobbin surface. This interaction can be taken into account by applying the coefficient of a torsional stiffness hardening, for which an analytical expression was obtained by processing the results of the computational experiment.Practical value. The developed mathematical model of determining the stiffness of the rubber-rope cable winding allows finding the parameters of the bobbin hoist, at which the danger of dynamic effects during the emergency and service braking caused by the torsional stiffness of the body of the winding is excepted.Keywords: bobbin hoisting machine, rubber-rope cable, multilayer winding, the body of the winding, torsional stiffness of the winding introduction. The multilayer winding of the rubberrope cable is one of the insufficiently explored elements of the bobbin hoisting machines, which has a high compliance and influences the dynamic processes in the hoisting installation. Because of the high compliance of the cable wound on the bobbin in a short branch, considerable oscillations of the lifting vessel can arise, which are dangerous for the possibility of its offset from the discharge curves. It follows from the foregoing that the evaluation of stiffness is an important problem, the solution of which is necessary for the research on dynamics of the hoisting installation. Analysis of the recent research and publications. The works of V. P. Franchuk and K. A. Ziborov [1] are devoted to the elaboration of mathematical models of the mechanical systems with distributed and lumped parameters during stationary and non-stationary rec...
When calculating the stress-strain state of a cylindrical drum of a mine hoisting machine loaded with a metal rope, the stiffness parameters of the elastic lining and frontal surface are taken into account. It is defined that, depending on the values of the radial and bending stiffness of the frontal surface, two zones can be distinguished. If the parameters of the frontal surface fall into the first of them, the stresses in the shell slightly differ from the stresses in the hinged supported shell. The second zone is characterized by a sharp (up to 70%) increase in stresses. An algorithm has been developed for selecting rational parameters of a lined drum, which allows to reduce the stresses in the metal shell by up to 20%.
By the example of justification of the design parameters of the fixed jaw body of the jaw crusher, the methods have been developed for choosing the optimal parameters according to the strength condition under restrictions on its mass. The practical value of the work is in development of the recommendations for designing the fixed jaw body, based on the criterion of minimum mass for the set tensile strength. It is shown that the use of the proposed recommendations allows to reduce the metal consumption of the jaw by 170 – 200 %.
Lagrange equations of the second kind are used to describe the dynamics of three-link manipulator lever tunnel stacker. Relative angles of rotation of manipulators units chosen as the generalized coordinates. The problem of the direct dynamics of the manipulator is solved. Expressions control torques for the main types of motion manipulators is given. With an accuracy of 11 %, using the motion simulation built in SOLIDWORKS Motion trajectory. Conclusions are drawn about selected control laws allowing to minimize the working time spent on the installation of the lining elements.
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