Penetration rate prediction for percussive drilling via dry friction model

A dynamic model of percussive drilling assuming a dry friction mechanism to explain the experimentally observed drop in penetration rate is presented. The inherent nonlinearity of the discontinuous impact process is modelled as a frictional pair, and this can generate the pattern of the impact force s close to reality. Despite quite radical simplifying assumptions, the mode l is able do describe the fall of material removal rate for a higher static loading with a good agreement to experimental investigations. (C) 2000 Els evier Science Ltd. All rights reserved.