The Influence of Gangue Particle size and Gangue Feeding Rate on Safety and Service Life of the Suspended Buffer’s Spring

Abstract

To address the problems of the suspended buffer spring’s safety and service life, we introduce the basic operating principles and structure parameters of the suspended buffer; followed by establishing a new numerical model of the buffer spring vibration using Femap software. The vibration characteristics of the spring form the basis for spring safety check and service life prediction. Therefore, the principles influencing the gangue particle size and feeding rate on the vibration characteristics of the buffer spring were analyzed. The results have indicated that the vibration frequency, axial pressure peak and the maximum and minimum axial pressure within the periodic vibration had power relations with gangue particle size D, while they had linear relations with the gangue feeding rate v except for the vibration frequency that had nothing to do with the feeding rate. According to the ultimate axial pressure of the spring, the relations between the shear pressure and tensile strength as well as the vibration characteristics, the spring’s safety check formula and service life formula were obtained. Based on the backfilling parameters of the working face in Dongping Coal Mine, the crushed gangue particle size and spring service life were determined. Based on the engineering practice in Dongping Coal Mine, the spring service life was obtained. And the fatigue fracture of the spring was also analyzed.

Keywords

• buffer spring
• safety
• service life
• gangue particle size
• gangue feeding rate
• impact