Parametric vibrations in mechanical systems on the example of a mining hoist installation

AGH University of Science and Technology, Kraków, Poland

^* Corresponding author: stwolny@agh.edu.pl

Abstract

This study summarises the research efforts undertaken to establish how variable stiffness of shaft steelwork should affect the amplitudes of horizontal displacements of selected components of a conveyance (skip head and skip bottom frame). Most studies investigating the dynamic behaviour of conveyances travelling in the shaft rely on a simplifying assumption whereby the shaft steelwork stiffness is taken to be constant, despite its cyclic variations. This simplification vastly facilitates further dynamic analyses, yet it is necessary to establish which parameters of the shaft steelwork behaviour should be affected, in the context of stiffness in the guiding systems. With regard to parameters of typical hoist installations currently operated in Polish collieries, the study demonstrates that the approach whereby the variable shaft steelwork and its impacts on amplitudes of horizontal displacements of selected components of a conveyance (skip head or bottom frame) should be omitted in the analysis of the hoist dynamics is fully justified and merited in practical applications.