Open AccessInfluence of the mechanical characteristics of harp screen material on screening process
Author(s) -
A. D. Bardovskii,
А. А. Герасимова,
A. M. Keropyan,
P. Ya. Bibikow
Publication year - 2018
Publication title -
izvestiâ vysših učebnyh zavedenij. černaâ metallurgiâ
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.3
H-Index - 7
eISSN - 2410-2091
pISSN - 0368-0797
DOI - 10.17073/0368-0797-2019-9-678-682
Subject(s) - strips , harp , vibration , natural rubber , amplitude , materials science , dimensionless quantity , structural engineering , composite material , acoustics , mechanics , engineering , optics , physics , quantum mechanics
The paper presents the results of studies on the influence of mechanical characteristics of harp screen material on the technological parameters of screening. A mathematical model of the vibrational process of harp screens is presented depending on the length of their free areas, magnitude of technological load and characteristics of the screened material. Dependences of the relative vibrations amplitudes of rubber and cable strips on the length of their free areas are determined for different values of process load. As a result of the researches, it was established that the amplitude of the relative vibration of rubber strip under load decreases with increasing length of their free areas and for steel cable strips it increases, reaching a maximum at certain values of process load. It was also found that presence of the load dramatically reduces the amplitude of relative vibration of rubber strips, especially, in the area of dimensionless frequencies of the order of (0.6 – 1.4)g, while the vibrations amplitude of cable strips vary slightly in this frequency range. The article presents information on rubber-cable harp screening surfaces of mesh type: strips in the form of steel cables, rubberized with rubber cover having lateral separation projections. The use of rubber-cable strips as working elements of the screening surface allows to increase the “open area” of the screen due to the increase of distance between supports while maintaining high and stable amplitude of strips vibrations. Optimization of mechanical characteristics of the working elements material of harp screens and conditions of their fixation allows to intensify separation of screened material into fractions by eliminating sticking of the screened surface with clay particles and clogging of the material with “difficult” grains, and to improve significantly technical and economic indicators of the screening process. Such screening surface passed successful industrial tests at a number of quarries producing construction aggregates for the separation of crushed stone and gravel. Economic efficiency of the rubber-cable harp screens is presented in comparison with the wire screens in technological schemes of processing of mineral raw materials.