Study of the dynamics of Oilwell drill strings during Backreaming operation

• Grant number: 12/13019-9
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2012
• End date: August 31, 2014
• Field of knowledge: Engineering - Mechanical Engineering - Mechanics of Solids
• Principal Investigator: Rodrigo Nicoletti
• Grantee: Rodrigo Nicoletti
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated researchers: Cristiano Eduardo Agostini

Abstract

The objective of this project is analyzing the dynamic effects in oilwell drill strings during backreaming operation, i.e. when the drill string is pulled out from the well. In this case, a laboratory test rig shall be built for correlating a reduced order numerical model, considering the uncertainty of parameters (stochastic modeling). The correlated numerical model will be used to analyze vibration data from real cases in off-shore oilwell rigs, aiming at evaluating the effects of impacts during backreaming in the dynamics of the drill string. Hence, by analyzing the behavior of the drill string during backreaming operation, it is expected to find optimum values for drilling parameters (rotating and withdrawal speeds) which minimize lateral vibration and reduce the effects of impacts to the walls of the well. (AU)