Investigation of stress-strain state of packet node connection in spatial vibration shakers

Abstract

Purpose. Using the study of stress-stain state of the CNs (connection nodes) used in multi-axis translational shakers formed as a package of TEEs (tape elastic elements), to formalize dependencies of their mechanical and structural parameters on the range of operating frequencies and the level of transmitted mechanical loads in the shaker node. Additionally, to take into account the impact of the force reproduced by the node on the elastic deformations of the unit considering that a particular tape unit undergoes bending in two planes, as well as displacement and stretching simultaneously. To develop a method for calculating the structural and mechanical parameters of the considered CNs regarding the known values of amplitude and frequency parameters yielded by the stand of dynamic loads. methodology. The study is based on the fundamental approaches of applied mechanics, modeling theory, machine dynamics and vibration reliability. findings. Dependences of thickness, length and width of the tape elastic elements, as well as their number in the package and the number of packages in the connection node in the direction of the transmitted vibration on the given stiffness and strength characteristics are obtained. A method is developed for calculating structural and mechanical parameters of the elastic elements, taking into account the specified parameters of the amplitude and frequency characteristics of strains reproduced by the stand. Originality. For the first time, a technique is proposed for calculating structural parameters (thickness, length, width of the tape, the number of elastic elements in the package, the number of packages in the CN) and the mechanical characteristics (compliance of the package, the endurance limit of the elastic element material) of the CN, taking into account the frequency range specified by the regulatory document and the levels of vibrational loads reproduced on the platform of the stand. In this case, the stress-strain state of each elastic element of the package includes its work on bending in two planes, displacement and stretching and satisfies the strength and rigidity conditions of the CN altogether. Taking into account the requirements for the preset rigidity of the package in the non-operational direction, and small value of tape thickness, the conditions of durability and rigidity are eventually satisfied due to the possibility to alter a number of tapes in the package. The stiffness of the package of elastic elements as well as the number of packets in the connection node are determined according to the conditions for carrying out vibration tests in the operating frequency ranges and the levels reproduced on the shaker table of mechanical loads. Practical value. The use of the considered CNs in the form of TEE packages for jointing the tables of vibration exciters with many degrees of freedom with a platform and a platform with a fixed base provides the following advantages: simplicity of manufacture; no additional energy costs for their maintenance; light weight that unlo...

Badanie wpływu kompensacji na stabilność górotworu oraz jakość wydobywanej rudy

“…Let's take the Dirac function in a form of a Fourier series on a given segment of cable numbers. From expression (4), we have the following (8) From where (9) From the condition that a load on the broken cable in the cross-section of breakage is equal to zero from expression (3) we have (10) Accordingly, expression (9) takes the form (11) Expressions of forces (3) and displacements (4) considering the general numeration of cables in the cross-section of a rope take the following forms (12) (13) Using ( 1), ( 2), ( 5), ( 6), ( 12), ( 13), we write down the values of forces and displacements as single functions on the finite axis of cable numbers (14) where (15) where Expressions ( 14), (15) are obtained for the first part of the rope for (0 ≤ x ≤ l0). In cross-section x = l0 the considered part of the rope interacts with its second part.…”

“…where At the same time, in cross-section x=l0 the conditions of joint deformation of rope parts must be fulfilled p 0,i = p i , (18) u 0,i = u i (19) From expressions ( 14), (15) and conditions ( 18), (19), we have equalities (20) (21) Subtract ( 21) from (20). We get a system of N -1 equations (22) The solution of obtained system of equations ( 22) allows determining the unknown constants and internal loading forces of cables, and their displacements.…”

“…Continuous improvement of technical systems in the fields of mining technologies [1][2][3][4][5][6][7][8][9], transportation and hoisting [10][11][12], deep-sea mining [13,14], and dynamics of technical systems [15][16][17][18][19] facilitate wider and more thorough development of analytical and computational simulation methods of processes and phenomena occurring within the systems. Currently, researchers in many countries are conducting complex scientific studies aimed at developing methods and means of modernizing lifting and transporting complexes with the aim of increasing operational efficiency and safety of mining transport equipment.…”

Analytical modelling and design of linear controlled dynamic systems

“…Continuous improvements in the fields of mining technologies [1][2][3][4], transportation and hoisting [5][6][7][8], technological processes [9][10][11][12], and dynamics of technical systems [13][14][15][16] facilitate wider and more thorough development of analytical and computational simulation methods of processes and phenomena occurring within the systems.…”

Stress state of elastic shell of standard sample in process of cable tear out testing

“…A wide variety of constructions of machines in different fields of mechanical engineering [1][2][3][4], transportation [5][6][7][8] and mining [9][10][11][12] is under constant enhancement to provide their more safe, reliable and productive operation.…”