Journal of South China University of Technology (Natural Science Edition) ›› 2016, Vol. 44 ›› Issue (11): 63-70.doi: 10.3969/j.issn.1000-565X.2016.11.010

• Mechanical Engineering • Previous Articles     Next Articles

Analysis of Dynamic Characteristic of Transient Impact from Hydraulic Hammer

DING Wen-si1,2 TIAN Li1 LIU Kun1,2   

  1. 1.School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China; 2.Hi-Tech Industrial Research Institute of SCUT,Shaoguan 512027,Guangdong,China
  • Received:2016-02-21 Revised:2016-06-01 Online:2016-11-25 Published:2016-10-04
  • Contact: 丁问司( 1968-) ,男,博士,教授,主要从事流体系统动力学控制研究. E-mail:wsding@scut.edu.cn
  • About author:丁问司( 1968-) ,男,博士,教授,主要从事流体系统动力学控制研究.
  • Supported by:
    Supported by the National Natural Science Foundation of China( 11272122) and the Special Funds for University- Industry Cooperation of Guangdong Province and the Ministry of Education of China( 2012A090300011)

Abstract:

On the basis of the transient stress wave propagation theory of one-dimensional vibration elastomer,a model is constructed to calculate the coaxial longitudinal collision of double flexible rod during the impact of hydraulic hammer drill rod on the corresponding piston.Then,the displacement-time transient response impact function of each impact part is solved by means of the eigenvalue expansion method of transient wave function,and the stress wave propagation rules of both the drill rod and the piston as well as the dynamic characteristics of each crosssection of both the drill rod and the piston are analyzed.Furthermore,the transient dynamic responses of impact parts with different drill rod lengths and diameters as well as with different initial speeds of piston are discussed.The results indicate that ( 1) drill rod length slightly affect the impact force and a short drill rod may result in a fast rebound of the piston; ( 2) with the increase of drill rod diameter,the impact force amplitude increases and the crushing ability improves,which means a relatively low energy efficiency; and ( 3) with the increase of the initial piston speed,the impact force proportionally increases and the crashing ability of hydraulic hammer greatly improves.These results can provide a theoretical basis for an optimization of the structure and performance of hydraulic hammers as well as a reasonable adjustment of construction parameters.

Key words: hydraulic hammer, dynamic characteristic, wave theory, transient response

CLC Number: