ANALYTICAL DETERMINATION OF THE REDUCED ROTATIONAL RESISTANCE COEFFICIENT OF THE CONSTRUCTION MACHINE SLEWING GEAR
Journal Title: Наука та прогрес транспорту - Year 2019, Vol 0, Issue 1
Abstract
<p class="Vis"><strong>Purpose. </strong>Designing new models of construction machines is closely related to the development of slewing gear, and that, in turn, has a drive whose power and dimensions depend on the rotational resistance and the reduced friction coefficient in the units. The absence of analytical dependencies for determining the reduced coefficient of friction for the rotation of construction machines, first, restricts the designer's ability to select materials, and secondly, does not allow the adoption of optimal design solutions. Therefore, the purpose of the article is to find analytical solutions to determine the rotational resistance in the slewing gear of construction machines, which allows projecting more advanced gears and machines in general. Existing techniques are based on empirical dependencies and experimental coefficients that reduce the accuracy of calculations, increase the size and cost of work. It is proposed to improve the accuracy and simplify the process of determining the rotational resistance and the magnitude of the reduced rotational resistance coefficient of the building tower cranes. <strong>Methodology.</strong> The set objectives can be achieved by means of analytical dependencies for determination of rolling friction coefficients over linear and point contacts. This will enables to find the more accurate value of the resistance coefficient, and the constructor during the calculations to take targeted measures to reduce it, using the mechanical constants of materials of the units and their geometric parameters. The calculation is based on Hertz contact deformation theory and the body point plane motion theory. <strong>Findings</strong>. The obtained dependencies will allow analytically to find the resistance of rolling resistance of rollers in construction machines with fixed and rotating pillars, with circular rotary devices, as well as in ball and roller slewing rings. The calculated values of the rotational resistance coefficients for some types of mechanisms give similar values with those recommended, while for others they significantly differ and require their refinement in reference values. <strong>Originality</strong> of the work consists in the use of analytical dependences for determining the reduced coefficient of the rotational resistance over linear and point contacts using Hertz contact deformation theory and Tabor partial analytic dependencies theory. <strong>Practical value.</strong> The obtained dependencies will allow to design new types of slewing gear units of the construction machines and to reveal the additional rotational resistances.</p>
Authors and Affiliations
L. Bondarenko, O. Posmityukha, K. Hlavatskyi
Keywords
Related Articles
- EP ID EP560205
- DOI 10.15802/stp2019/159499
- Views 103
- Downloads 0
ЭКСПЕРИМЕНТАЛЬНЫЕ ИССЛЕДОВАНИЯ ДИНАМИКИ ЦЕНТРОБЕЖНОЙ ЛИТЕЙНОЙ МАШИНЫ ДЛЯ ПРОИЗВОДСТВА ПРОКАТНЫХ ВАЛКОВ
Цель. Основной целью экспериментальных исследований является установка адекватности разработанных математических моделей колебаний машины и фактических параметров вибрации машины. Практически все литейные машины для прои...
STUDY OF TECHNICAL STATE IMPACT OF BRAKE RETARDERS AT THE PROCESSING ABILITY OF HUMPS
Purpose. The research aims development of methods for calculating the estimated capacity humps for the loss conditions of brake power retarders. Methodology. The operation of humps is connected with large number of rando...
ТЕОРЕТИЧНИЙ БАЗИС ПАРАМЕТРИЧНОГО СИНТЕЗУ НЕСУЧИХ СИСТЕМ ВАГОНІВ
Мета. В статті потрібно розглянути систематизоване та структуроване представлення теоретичних основ оптимізаційного проектування вагонних складових та практичних засобів його реалізації. Методика. Проведене дослідження,...
THEORETICAL AND EXPERIMENTAL RESEARCH OF STRENGTH PROPERTIES OF SPINE BEAM OF FREIGHT CARS
Purpose. The purpose of this paper is to analyze the results of theoretical and experimental studies of the strength properties of rolling stock; search for design tools, modeling, selection, justification of the service...
OPTIMIZATION OF SUPPLY AND SALES ACTIVITIES OF THE ENTERPRISE THROUGH THE APPLICATION OF LOGISTIC PRINCIPLES
Purpose. Procurement is a very important field of activity for an industrial enterprise. Therefore, the purpose of this paper is to study it in detail and analyze possible ways to improve supply activities. Methodology....