Estudo do dano em cabo de aço utilizados em equipamentos de transporte vertical

Abstract

The steel wire rope is one of the main elements in lifting or weight load transportation equipments. During the operation of the equipments, the steel wire rope is subjected to oscillatory movements that cause wear and even cracking in the material. In order to evaluate the damage caused in a steel wire rope subjected to low amplitude vibrations, an experimental apparatus was designed and installed to simulate the operation of a lifting system using sheaves and a steel wire rope with the following construction: 1/4” 6x19 S FC RR bright. In this experimental apparatus, the steel wire rope was loaded with 25 N in order to exert the proper tension for the operation of the equipment. Steel wire rope samples were collected and analysed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) before the experiment, then after a run of 120,000 cycles and 3,000,000 cycles. This work revealed surface damages in the studied material inherent to the manufacturing process of the steel wire rope and allowed the visualisation of surface damage in specific contact regions of the steel wire rope, revealing several mechanisms of damage acting in a steel wire rope subjected to a pressure x slip speed pair. In the carried out tests, the experimental apparatus was configured to promote oscillatory motion with a maximum amplitude of 300 μm in order to simulate shocks on the steel cable that resemble the operating reactions of this system in the field. The definition of the analysis methods in this study and the evaluation of the surface damage caused in the laboratory is fundamental to introduce means of predictive maintenance in the industry, as well as products or resources to minimize the wear and to increase the lifespan of the material.