Characteristics and control of impact vibration and noise in rail belt conveyor

Abstract

The rail belt conveyor is an innovative energy-saving belt conveyor. Revolutionizing the traditional roller support, it utilizes interval-spaced carriages to support the conveyor belt. The study of impact vibrations in rail belt conveyors remains underexplored in current research. This paper investigates the impact vibration and noise characteristics of the wheel–rail-steel structure coupling system, as well as their control and optimization strategies. First, vibration and noise measurements were conducted along the track. Results indicate that impact vibrations and noise originating from expansion joints and inserted joints fall within the frequency range of 1.5 kHz–5 kHz. Particularly noteworthy is the pronounced impact noise near inserted joints, with dominant frequencies ranging from 1.5 kHz to 2.5 kHz. Further investigation has revealed that the impacts on inserted joints encompass interactions between the wheel and rail, as well as between different sections of the rail itself. Next, the characteristics of filler materials such as polyurethane rubber, silicone, polyurethane resin, and epoxy resin were analyzed and compared. The experimental results show that filling rubber in expansion joints can reduce lateral impact vibrations by 61% and vertical impact vibrations by 66%. Additionally, the sound pressure level was reduced by approximately 1.7 dBA. Finally, welding the guiding rail to its preceding rail and grinding the welded surface effectively eliminated the composite impact vibrations and sharp noise at the inserted joint, resulting in a decrease of approximately 3 dBA in the sound pressure level. This paper provides guidance on the structural improvement and acoustic optimization of rail belt conveyors.