Hammer Structure of Liquid-Jet Hammer Based on Ls-dyna

doi:10.12068/j.issn.1005-3026.2016.10.016

Abstract

Abstract: A “hammer-bit-rock” impacting model was established based on the methods of the Ls-dyna explicit nonlinear kinetic simulation， and the geometrical parameters of hammer in liquid-jet hammer were studied. The effects of hammer length and diameter on energy transfer for different rocks were studied with constant mass and impact speed of hammer. The strength analysis was also made to investigate the optimal structure of a hammer. The results showed that the energy absorbed by rock increases with the decrease of the hammer diameter. When the hammer length is the optimal value， the rock can achieve the most impact energy， otherwise the energy absorbed by rock may decrease. The higher the drillability grade of rock and the impact velocity， the less the influence of hammer structure on rock breakage. The maximum stress always appears at the end of the bit and stress concentration will be found on the edge of relatively small area. The design of hammer should take the allowable strength of bit into account.

Key words: liquid-jet hammer, hammer, geometrical parameter, energy transfer, stress

CLC Number:

P634
TH113

WU Dong-yu， PENG Jian-ming， YIN Kun， ZHANG Xin-xin. Hammer Structure of Liquid-Jet Hammer Based on Ls-dyna[J]. Journal of Northeastern University Natural Science, 2016, 37(10): 1441-1445.

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