Patent ID: 8977523
Filing Date: 2015-03-10
Classification: E21B,G05B

Abstract:
1. A method to estimate severity of downhole vibration for a wellbore drill tool assembly, comprising the steps: a. Identifying a dataset comprising selected drill tool assembly parameters; b. Selecting a reference level of downhole vibration amplitude for the drill tool assembly; c. Identifying a surface drilling parameter and using a computer processor to calculate a reference surface vibration attribute for the selected reference level of downhole vibration amplitude; d. Determining a surface parameter vibration attribute derived from at least one surface measurement or observation obtained in a drilling operation, the determined surface parameter vibration attribute corresponding to the identified surface drilling parameter (step c); and e. Estimating a downhole vibration severity indicator by evaluating a ratio between the determined surface parameter vibration attribute (step d) and the identified calculated reference surface vibration attribute (step c).