Simulation Analysis On Vibration Of Vertical-oil-well Drill String Based On ANSYS

Drill string is the most important part of drill system. The vibration of drill string can reduce the service life of drill string and cause losses to drilling projects. Drill string vibration is caused by alternating drill bit loads and changing geological structure. Axial, torsional and lateral vibration of the drill string vibration are the main form and often occur simultaneously. When the frequency of vibration of the drill string is close to the natural frequency of drill string, the alternating stress and vibration amplitude will gradually become larger, resulting in damage to the drill string.Drill string and basic problems of vibration are introduced in this paper. Studies in this area are also introduced. Basing on FEM-software ANSYS, a vertical drilling system is established under simplified conditions with drill string protectors. Axial, torsional and lateral natural frequency and frequency response of the system are separately studied via modal analysis and harmonic analysis.