Method and apparatus for installing deflecting conductor pipe

Abstract

Delivering an additional subterranean conduit ( 124 ) along a deflected path relative to an existing conduit ( 120 ) is used for installing additional conductor pipes ( 124 ) from an existing production platform ( 50 ). A deflecting member in the form of a shoe ( 114, 115; 214 ) has a coupling means in the form of a screwthread for coupling to a lowermost end of an additional conduit ( 124 ). The shoe ( 114, 115; 214 ) is arranged to deliver the additional conduit ( 124 ) along the deflected path when the shoe ( 114, 115; 214 ) contacts whipstock ( 126; 226 ) which has been installed on top of an existing conductor pipe ( 120 ). The method can include running in the whipstock ( 126; 226 ) as a first step on an elongate member such as a drill string ( 94 ) and then withdrawing the drill string ( 94 ) and then running in the additional conduit ( 124 ). The outer diameter of the additional conduit ( 124 ) is maximised as it passes through conductor guides ( 52 ) attached to the production platform ( 50 ).

1 - 39 . (canceled) 
   
   
       40 . An apparatus to deliver a secondary conduit along a path deflected relative to a pre-existing conduit, the apparatus comprising:
 a whipstock delivered to a deflection point above an upper end of the preexisting conduit;   a coupling disposed at a distal end of the whipstock, wherein the coupling is configured to secure the whipstock to the pre-existing conduit at a selected orientation;   wherein the selected orientation aims a trough of the whipstock in a desired trajectory; and   a deflecting shoe connected to a distal end of the secondary conduit, wherein the deflecting shoe is configured to engage the trough of the whipstock and deflect the secondary conduit at the desired trajectory.   
   
   
       41 . The apparatus of  claim 40 , wherein the deflecting shoe comprises a drillable material. 
   
   
       42 . The apparatus of  claim 40 , wherein the deflecting shoe comprises holes extending therethrough, wherein the holes permit the passage of materials between an outer surface of the deflecting shoe and a bore of the secondary conduit. 
   
   
       43 . The apparatus of  claim 40 , wherein the deflecting shoe comprises a substantially conical outer surface. 
   
   
       44 . The apparatus of  claim 40 , wherein an inner diameter of the whipstock is less than an outer diameter of the secondary conduit. 
   
   
       45 . The apparatus of  claim 40 , wherein the deflecting shoe comprises a head portion and a collar portion, wherein the head portion is larger in diameter than the collar portion. 
   
   
       46 . The apparatus of  claim 45 , wherein a neck portion is provided between the head portion and the collar portion, wherein the neck portion comprises an outwardly projecting shoulder extending in a radial direction with respect to a longitudinal axis of the deflecting shoe. 
   
   
       47 . The apparatus of  claim 45 , further comprising a first coupler on the outer surface of the collar portion, the coupler configured to couple to a corresponding second coupler of the distal end of the secondary conduit. 
   
   
       48 . The apparatus of  claim 47 , wherein the first and the second couplers comprise corresponding screw threads. 
   
   
       49 . A method to deliver a secondary conduit in a path deflected from a pre-existing conduit, the method comprising:
 providing a deflecting shoe to a lower end of the secondary conduit;   providing a whipstock to an upper end of the pre-existing conduit;   delivering the lower end of the additional conduit to the whipstock through at least one guide member;   securing the whipstock to the preexisting conduit;   urging the additional conduit in a desired trajectory with a trough of the whipstock; and   deflecting the additional conduit away from the pre-existing conduit in the desired trajectory.   
   
   
       50 . The method of  claim 49 , further comprising delivering the whipstock to the upper end of the pre-existing conduit at the end of a delivery conduit. 
   
   
       51 . The method of  claim 49 , further comprising delivering the whipstock to the upper end of the pre-existing conduit upon the lower end of the secondary conduit. 
   
   
       52 . The method of  claim 51 , further comprising delivering the whipstock and urging the additional conduit in the desired trajectory in a single trip. 
   
   
       53 . The method of  claim 51 , further comprising shearing the whipstock from the secondary conduit when secured to the pre-existing conduit. 
   
   
       53 . The method of  claim 49 , further comprising coupling the whipstock about an outer diameter of the preexisting conduit. 
   
   
       54 . The method of  claim 49 , further comprising coupling the whipstock within an inner diameter of the pre-existing conduit. 
   
   
       55 . The method of  claim 49 , further comprising deploying the whipstock to the pre-existing conduit through the at least one guide member. 
   
   
       56 . The method of  claim 55 , further comprising expanding a diameter of the trough of the whipstock with a larger diameter of the secondary conduit. 
   
   
       57 . The method of  claim 49 , further comprising longitudinally loading the secondary conduit to deflect it away from the pre-existing conduit in the desired trajectory.