Wellbore encasement

Abstract

A method of encasing a wellbore is provided comprising the application of 3D printing technology to apply a series of layers of lining material to the interior surface of a wellbore. The layers may be of different materials to make best use of their different material properties, to provide structural integrity and good sealing properties, for example. Through suitable printhead control, specific structural features such as channels for receiving measurement, power or communications equipment may be incorporated into the lining structure. Associated devices for depositing the layers of lining material are also provided.

1 . A method of lining a wellbore comprising the steps of:
 inserting a directional nozzle into the wellbore; and   controlling the direction of the nozzle and controlling flow through the nozzle to deposit at least one layer of lining material onto the interior surface of the wellbore.   
     
     
         2 . The method of  claim 1 , wherein controlling the direction of the nozzle comprises rotating the nozzle about the longitudinal axis of the wellbore. 
     
     
         3 . The method of  claim 1 , wherein controlling the direction of the nozzle comprises displacing the nozzle along the longitudinal axis of the wellbore. 
     
     
         4 . The method of  claim 1 , wherein controlling the direction of the nozzle comprises rotating the nozzle relative to the longitudinal axis of the wellbore. 
     
     
         5 . The method of  claim 1 , wherein multiple layers of lining material are deposited onto the interior surface of the wellbore. 
     
     
         6 . The method of  claim 1 , wherein the nozzle is controllable to deposit different materials. 
     
     
         7 . The method of  claim 1 , wherein multiple nozzles are inserted into the wellbore, each controllable to deposit a different respective material. 
     
     
         8 . The method of  claim 7 , wherein the multiple nozzles are mounted on a common printhead. 
     
     
         9 . The method of  claim 1 , wherein the at least one material is selected from the group consisting of cement, concrete, resins, plastics, metals, ceramics, rubber, plastics, bitumen, and neoprene. 
     
     
         10 . The method of  claim 1 , further comprising a step of inserting a casing pipe into the wellbore. 
     
     
         11 . The method of  claim 10 , wherein the casing pipe is inserted into the wellbore before the directional nozzle is inserted into the wellbore. 
     
     
         12 . The method of  claim 11 , wherein the directional nozzle is inserted through the interior of the casing pipe. 
     
     
         13 . The method of  claim 10 , wherein the directional nozzle is inserted on the exterior of the casing pipe. 
     
     
         14 . The method of  claim 10 , including a step of inserting a bung between the casing pipe and the interior surface of the wellbore, wherein the step of controlling the direction of the nozzle and controlling flow through the nozzle comprises depositing the at least one layer of lining material onto the bung and thereby onto interior surface of the wellbore. 
     
     
         15 . The method of  claim 14 , wherein the at least one layer of material is deposited from above the bung. 
     
     
         16 . The method of  claim 14 , wherein the at least one layer of material is deposited from below the bung. 
     
     
         17 . The method of  claim 10 , further including a step of determining the topography of the borehole, the control of the direction of the nozzle and the control of the flow through the nozzle being dependent on the topography. 
     
     
         18 . The method of  claim 10 , further including a step of accelerating a cure of the deposited material prior to deposition of a subsequent layer. 
     
     
         19 . A device for depositing at least one layer of material onto an interior surface of a wellbore, comprising:
 a directional nozzle;   a source of material in connection with the nozzle;   means to control the direction of the nozzle; and   means to control the passage of the material through the nozzle, whereby to deposit at least one layer of lining material onto the interior surface of the wellbore.   
     
     
         20 . The device of  claim 19 , wherein the nozzle is mounted for rotation about a vertical axis. 
     
     
         21 . The device of  claim 19 , wherein the nozzle is mounted for displacement along a vertical axis. 
     
     
         22 . The device of  claim 19 , wherein the nozzle is mounted for rotation relative to a vertical axis. 
     
     
         23 . The device of  claim 19 , wherein the nozzle is selectively in connection with multiple sources of different materials. 
     
     
         24 . The device of  claim 19 , comprising multiple nozzles, each in connection with a different respective source of material. 
     
     
         25 . The device of  claim 19 , wherein the or each nozzle is mounted on a common printhead. 
     
     
         26 . The device of  claim 19 , wherein the source of material is selected from the group consisting of cement, concrete, resins, plastics, metals, ceramics, rubber, plastics, bitumen, and neoprene. 
     
     
         27 . The device of  claim 19 , configured for insertion through a wellbore casing pipe. 
     
     
         28 . The device of  claim 27 , wherein the or each nozzle is mounted on an arm that is able to bend so as to position the nozzle directed generally upwards into the annulus between the wellbore casing pipe and the interior surface of the wellbore. 
     
     
         29 . The device of  claim 28 , wherein the at least one nozzle is connected to the associated source of material via a flexible conduit. 
     
     
         30 . The device of  claim 19 , configured for insertion over a wellbore casing pipe, between the exterior of the wellbore casing pipe and the interior surface of the wellbore. 
     
     
         31 . The device of  claim 30 , wherein the or each nozzle is mounted on a ring having a diameter substantially matching that of the wellbore casing pipe so as to position the nozzle directed generally downwards. 
     
     
         32 . The device of  claim 25 , comprising multiple printheads positioned at regular circumferential intervals. 
     
     
         33 . The device of  claim 19 , further comprising a controller to control the direction of the nozzle and the flow of material through the nozzle. 
     
     
         34 . The device of  claim 33 , wherein the controller is programmed to deposit the material along an optimum path. 
     
     
         35 . The device of  claim 34 , further comprising means for determining the topography of the borehole, wherein the optimum path is determined at least partly on the basis of the determined topography. 
     
     
         36 . The device of  claim 33 , wherein the controller is programmed to deposit the material in multiple layers. 
     
     
         37 . The device of  claim 19 , further comprising a UV source for accelerating the curing of the deposited material.