Drill String Suspension

Abstract

Vertical and/or directional drilling apparatus where compliant support air bag, magnetic or the like) is provided for a vibrational head and drive assembly that carries the drill string. With the vibrational head having a shuttle from which vibration is not directly taken and with the compliant support allowing pull back in the directional mode several advantages arise.

1 . A vibrational apparatus comprising or including
 a support,   a vibrational head selectively operable to provide a vibrational output, and   apparatus or an assembly (hereafter “assembly”) to receive the vibrational output directly or indirectly from said vibrational head,   wherein said vibrational head and the directly or indirectly connected assembly to receive the vibrational output is flotably located relative to, yet is carriable or carried by, said support.   
   
   
       2 . The vibrational apparatus of  claim 1  wherein the flotable location is reliant on at least one compliant gas reservoir interposed between the support and said vibrational head. 
   
   
       3 . The vibrational apparatus as claimed in  claim 1  wherein (a) there is at least one compliant gas reservoir interposed between the support and said vibrational head so as to resist movement in a first direction parallel to the vibrational output from the vibrational head and (b) there is at least one compliant gas reservoir interposed between said support and said vibrational head to resist movement in a second direction opposite said first direction. 
   
   
       4 . The vibrational apparatus as claimed in  claim 1  wherein said vibrational head includes a shuttle and the vibrational output of the vibrational head is not directly from the shuttle itself. 
   
   
       5 . The vibrational apparatus as claimed in  claim 4  wherein the shuttle acts through a fluid to provide said vibrational output to said assembly. 
   
   
       6 . The vibrational apparatus as claimed in  claim 4  wherein said shuttle is able to shuttle reproducibly on a shuttle axis relative to at least one complementary structure of the vibrational head from which complementary structure(s) there is to be the vibrational output, and wherein there is a drive to rotate the shuttle about a rotational axis which is the shuttle axis, or is parallel to the shuttle axis, thereby to cause magnetic interactions which has the effect of driving the shuttle back and forth. 
   
   
       7 . The apparatus of  claim 1  wherein the or each said compliant gas reservoir is a gas bag. 
   
   
       8 . The apparatus of  claim 1  wherein said assembly is a drill string assembly. 
   
   
       9 . The apparatus of  claim 8  which includes, at or adjacent the vibrational head, a drive to rotate said drill string assembly. 
   
   
       10 . The vibrational apparatus as claimed in  claim 8  wherein the drill string assembly can rotate in either direction. 
   
   
       11 . A drilling apparatus comprising or including
 a support, and   a vibrational head adapted to be connected directly or indirectly to a drill string so as to both carry the drill string as a dangling assembly and to provide axial vibration thereinto;   and optionally a drive to rotate such a drill string when connected;   and optionally, a said drill string directly or indirectly connected to or connectable to said vibrational head so as selectively to be vibrated thereby and, when so connected, selectively adapted to be rotated by said drive,   wherein said vibrational head and any directly or indirectly connected drill string is flotably located relative to, yet is carriable or carried by, said support.   
   
   
       12 . The drilling apparatus of  claim 11  wherein the flotable location is reliant on at least one compliant gas reservoir interposed between the support and said vibrational head. 
   
   
       13 . The drilling apparatus of  claim 11  wherein the drill string is connected. 
   
   
       14 . The drilling apparatus as claimed in  claim 11  wherein there is a drive to rotate said or a drill string. 
   
   
       15 . The drilling apparatus as claimed in  claim 14  wherein said drive is at or adjacent the vibrational head. 
   
   
       16 . The drilling apparatus of  claim 11  wherein the flotable relativity is so as to facilitate vibrational axial input into any such connected drill string irrespective of whether or not the drill string is under pressure. 
   
   
       17 . The drilling apparatus of  claim 11  wherein the flotable relativity is so as to facilitate vibrational input irrespective of the downhole status of the drill string relative to the drill face. 
   
   
       18 . The drilling apparatus of  claim 11  wherein (a) there is at least one compliant gas reservoir interposed between the support and said vibrational head so as to resist movement in a first direction parallel to the vibrational output from the vibrational head and (b) there is at least one compliant gas reservoir interposed between said support and said vibrational head to resist movement in a second direction opposite said first direction. 
   
   
       19 . The drilling apparatus of  claim 11  wherein said vibrational head includes a shuttle and the vibrational output of the vibrational head to any connected drill string is not directly from the shuttle itself. 
   
   
       20 . The drilling apparatus as claimed in  claim 19  wherein the shuttle acts through a fluid to provide said vibrational output to the or a said drill string. 
   
   
       21 . The drilling apparatus of  claim 18  wherein said shuttle is able to shuttle reproducibly on a shuttle axis relative to at least one complementary structure of the vibrational head from which complementary structure(s) there is to be the vibrational output, and wherein there is a drive to rotate the shuttle about an axis which is the shuttle axis, or is parallel to the shuttle axis, thereby to cause magnetic interactions which has the effect of driving the shuttle back and forth. 
   
   
       22 . The drilling apparatus of  claim 11  wherein the or each said compliant gas reservoir is a gas bag. 
   
   
       23 . (canceled) 
   
   
       24 . (canceled)