This paper provides some new insights into stick-slip vibration in drilling with polycrystalline diamondcompact (PDC) bits. Fifty-six field runs under various drilling conditions were collected with the help of on-bit vibration sensors. Stick-slip vibration occurrence during drilling was analyzed. Two types of stick-slipvibrations were identified: cutting action-induced stick-slip and friction-induced stick-slip. Methods weredeveloped to determine whether a stick-slip occurrence is induced by cutting action or by friction. Statisticalanalysis found that bit drilling efficiency is well correlated with the occurrence of cutting action-induced bitstick-slip vibration. If a PDC bit is designed so that its drilling efficiency is greater than a critical value, thenthe cutting action-induced bit stick-slip vibration is not expected in drilling. Increasing the aggressivenessof the cutting structure of a PDC bit within a limited critical depth of cut is found to be helpful to mitigatebit stick-slip vibration.
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