Patent ID: 6725923
Filing Date: 2004-04-27
Classification: E21B

Abstract:
A method for exciting transverse vibrations of a pipe string partly or fully filled with one or more liquids or fluids, the method comprising:placing one or more hammers on a flexible suspension support into the pipe string; and exciting periodic radial oscillations in said one or more hammers resulting in said one or more hammers transversely hitting said pipe string; wherein said one or more hammers are made to provide a ratio of their maximum cross-section to an inner transverse cross-section of the pipe string within a limit of 0.9-0.98; and wherein said periodic radial oscillations of said one or more hammers are produced due to an axial motion of said one or more hammers in said pipe string and a speed of said axial motion is selected to produce a hit of required strength.