System And Method For Drill String Vibration Control

Abstract

A drilling assembly includes a derrick, a swivel assembly coupled to the derrick, and a drill string coupled to the swivel assembly. The drill string includes a plurality of pipe sections, each having an insert providing a material and/or geometrical discontinuity in the pipe section, the plurality of pipe sections forming periodic cells collectively operative to selectively block propagation of vibrations in the drill string.

1 . A drill string comprising:
 a plurality of pipe sections, each having an insert providing a material and/or geometrical discontinuity in the pipe section, the plurality of pipe sections forming periodic cells collectively operative to selectively block propagation of vibrations in the drill string.   
     
     
         2 . The drill string of  claim 1 , wherein said blocking is a function of vibrational frequency. 
     
     
         3 . The drill string of  claim 1 , wherein said inserts are passive. 
     
     
         4 . The drill string of  claim 1 , wherein said inserts are active. 
     
     
         5 . The drill string of  claim 4 , wherein the inserts comprise piezoelectric devices. 
     
     
         6 . The drill string of  claim 4 , wherein the inserts comprise shape memory devices. 
     
     
         7 . The drill string of  claim 1 , wherein said inserts are provided over substantially the entire length of the drill string. 
     
     
         8 . The drill string of  claim 1 , wherein said inserts are clustered over one or more portions of the drill string. 
     
     
         9 . A drilling assembly comprising:
 a derrick;   a swivel assembly coupled to the derrick;   a drill string coupled to the swivel assembly, the drill string comprising:
 a plurality of pipe sections, each having an insert providing a material and/or geometrical discontinuity in the pipe section, the plurality of pipe sections forming periodic cells collectively operative to selectively block propagation of vibrations in the drill string. 
   
     
     
         10 . The drilling assembly of  claim 9 , wherein said blocking is a function of vibrational frequency. 
     
     
         11 . The drilling assembly of  claim 9 , wherein said inserts are passive. 
     
     
         12 . The drilling assembly of  claim 9 , wherein said inserts are active. 
     
     
         13 . The drilling assembly of  claim 12 , wherein the inserts comprise piezoelectric devices. 
     
     
         14 . The drilling assembly of  claim 12 , wherein the inserts comprise shape memory devices. 
     
     
         15 . The drilling assembly of  claim 9 , wherein said inserts are provided over substantially the entire length of the drill string. 
     
     
         16 . The drilling assembly of  claim 9 , wherein said inserts are clustered over one or more portions of the drill string. 
     
     
         17 . A method for suppressing vibrations in drill string comprising:
 providing a plurality of periodic inserts along a portion of the drill string.   
     
     
         18 . The method of  claim 17 , wherein said suppression is a function of vibrational frequency. 
     
     
         19 . The method of  claim 17 , wherein said inserts are passive. 
     
     
         20 . The method of  claim 17 , wherein said inserts are active. 
     
     
         21 . The method of  claim 20 , wherein the inserts comprise piezoelectric devices. 
     
     
         22 . The method of  claim 20 , wherein the inserts comprise shape memory devices. 
     
     
         23 . The method of  claim 17 , wherein said inserts are provided over substantially the entire length of the drill string. 
     
     
         24 . The method of  claim 17 , wherein said inserts are clustered over one or more portions of the drill string.