Study on the Resonance Restraint of a Large Hoist System Headframe

Abstract

Headframe resonance is a major cause of large hoist system damage and instability. Therefore, restraining the resonance of a large hoist system headframe is critical for reducing shock and vibrations, thereby maintaining the safety and reliability of the mining equipment. In this study, an approach was developed to restrain the resonance of a large hoist system headframe. A finite element model of a large hoist system headframe was established. Simulations were carried out, and the modal characteristics of the large hoist system headframe were obtained. The results showed that the second- and third-order natural frequencies were both close to 1.5[Formula: see text]Hz. Furthermore, experiments were conducted. An analysis of the experimental and simulation results indicated that a vibrational forcing with a frequency of 1.56[Formula: see text]Hz was a key factor causing resonance of the large hoist system headframe. Moreover, 14 different retrofitting approaches were proposed to change the natural frequencies of the large hoist system headframe, thereby providing resonance restraint. The main retrofitting concept is to add new assembled steel box structures with inner stiffeners between the transverse beams and oblique brackets in the middle area of the large hoist system headframe. In addition, the weight added by the retrofitting approach should be minimized to reduce the construction difficulties and costs. After a comprehensive comparison, an optimal retrofitting design of the 14 retrofitting approaches considered was selected. This optimal retrofitting approach provides guidance for restraining the resonance of large hoist system headframes. Furthermore, this study provides a method for the design of large hoist system headframes and the determination of the vibration characteristics.