Rigidity of elastic shell of rubber-cable belt during displacement of cables relatively to drum

Analytical dependencies for determining the rigidity and parameters of a stress-strain state of a rubber layer located between the cables and the drum from their mutual shear are established in a closed form. A method of determining the dispersion of deviation of calculated displacements from established values of elastic shell material is developed. Obtained results allow considering the shape of an elastic layer of rubber, estimate the level of reliability of the results when calculating a stress-strain state of rubber-cable tractive elements from the shear of cables relatively to the drum. Established dependencies can be used for determining a stress-strain state of a layer of elastic material, caused by shear of cables relatively to the drum of a machine, and formulating the condition of strength of a rubber-cable tractive element loaded with shear forces on a drum. Possibility of determination of a lower boundary of the efficiency coefficient in a process of interaction of a rubber-cable rope (belt) with pulleys and drums, both driving and driven, lined with elastic materials and with hard operating surfaces, allows improving the accuracy of calculations of drives of lifting and transporting machines with such executing elements.

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Stress State of an Inhomogeneous Elastic Layer Made of Heterogeneous Materials with a Coin-Like Rigid Inclusion under Torsion

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.828.18 ◽

2019 ◽

Vol 828 ◽

pp. 18-23

Author(s):

Zaven Davtyan ◽

Anush Gasparyan ◽

Avetik Melkonyan

Keyword(s):

Elastic Layer ◽

Strain State ◽

Practical Importance ◽

Compound Layer ◽

Elastic Solids ◽

Stress Strain ◽

Stress Strain State ◽

Tangential Forces ◽

Inhomogeneous Elastic Layer

Problems on cracks and inclusions closely relate to problems of determination of the stress-strain state of homogeneous and inhomogeneous elastic solids that contain stress concentrators. Due to their theoretical and practical importance to the issues of construction structures, machines and their parts in machinery, in the calculation of hydro-technical structures as well as in various other spheres of applied mechanics, these problems have become a subject of investigation for many authors. This paper studies the problem of determination of the stress-strain state of a piecewise homogeneous elastic layer under torsion. The upper and lower surfaces of the compound layer are loaded with tangential forces and the interface of the heterogeneous layers contains a thin absolutely rigid coin-like inclusion. It is required to determine stress jumps on the boundary of the inclusion as well as intensity coefficients of the stresses (ICS).

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Influence of breakages of cable groups on strength ofrubber-cable tractive-transporting element

Collection of Research Papers of the National Mining University ◽

10.33271/crpnmu/64.166 ◽

2021 ◽

Vol 64 ◽

pp. 166-174

Author(s):

I Belmas ◽

D Kolosov ◽

O Dolgov ◽

H Tantsura ◽

S Onyshchenko

Keyword(s):

Cross Section ◽

Cross Sections ◽

Strain State ◽

Elastic Shell ◽

Practical Significance ◽

Analytical Determination ◽

Shear Stresses ◽

Stress Strain ◽

Stress Strain State

Purpose. Development and justification of a method of analytical determination of a stress-strain state of a flat rubber-cable tractive-transporting element with breakages of continuity of cable groups in different cross-sections. Methodology of research is in development of a mathematical model of interaction of tractive-transporting element parts considering breakages of groups of random cables, construction of analytical solutions for determining dependencies of force distribution between cables and shear stresses in an elastic shell of a tractive-transporting element with random locations of breakages of cable groups in different cross-sections. Findings. A model of a flat rubber-cable tractive-transporting element with random locations of breakages of cable groups in different cross-sections is developed. Expressions that allow determining a stress-strain state of a flat rubber-cable tractive-transporting element of a hoisting and transporting machine with random locations of breakages of cable groups in different cross-sections are obtained analytically in a closed form. Strength conditions are formulated. Scientific novelty is in establishment of dependencies of interaction of disturbance fields of a stress-strain state of a rubber-cable tractive-transporting element with breakages of continuity of random cable groups in different cross-sections. It is established that disturbance fields caused by breakages of adjacent cables overlap when the breakages are located in one cross-section and there are less than three whole cables located between the broken cables. Disturbance fields also overlap when the same cable or the adjacent cable is broken in both cross-sections and the distance between cross-sections of breakage does not exceed the value, which depends on the design of a flat rubber-cable tractive-transporting element and mechanical properties of its components. Practical significance. The obtained algorithms and strength conditions allow determining a stress-strain state and preventing the breakage of the entire flat rubber-cable tractive-transporting element with breakages of cable groups in different cross-sections. These cross-sections can be: cross-section of the edge of a butt joint, where cables have breakages of continuity; cross-section, which includes the edge of an area of partial restoration of a tractive ability of the element, lost due to breakage of a cable; cross-section of cable or cable group breakage during operation. A possibility of establishing a stress-strain state and the strength conditions of a tractive-transporting element under such conditions allows reasonable determination of a possibility of its further operation in a hoisting and transporting machine.

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