Stability analysis of the screening process of a vibrating flip-flow screen

[Display omitted] •Stability mechanism of dynamic response in different regions was investigated.•A reasonable working region for a loading VFFS was proposed.•The screening mechanism of particles on elastic sieve mat was revealed.•A good performance of VFFS was illustrated for screening 3 mm material. Deep dry screening is the key unit in mineral processing. A vibrating flip-flow screen (VFFS) with elastic sieve mats has been widely used for screening fine-grained minerals due to its good performance. The stability of the VFFŚs dynamic response largely affects its screening efficiency and processing capacity, however, it has rarely been investigated in detail. In this paper, aiming at reducing the effect of loading-material for dynamic system through properly operated parameters, stability regions were defined, and for the given working conditions, using performance criteria to evaluate the vibration stability. This was done by theoretical modeling and experimental analysis for the VFFS system. The VFFS can operate in different regions by regulating the shear spring characteristics and the eccentric mass moment. The dynamic response curves were measured and analyzed under different operating conditions; and then, material-loading experiments were carried out to verify the stability of VFFS; furthermore, the method of multistage sampling and multilayer was used to analyze the screening performance of material under three conditions. Results indicated that loading material on VFFS affected its vibration stability and therefore the screening performance. The dynamic response of VFFS was more stable in the near anti-resonance region (a certain distance to the left of anti-resonance frequency) than the other two operating conditions, thus, was not obviously affected by loading material. Screening efficiency for 3 mm material was up to 89.05% with a corresponding total misplaced material of 7.96%.