Guided Mainbore Mill Through Multilateral Junction

Abstract

Disclosed herein are various embodiments of a downhole system having a millable joint with a first portion shaped to extend into a main wellbore and a second portion shaped to extend into a lateral wellbore, a cutting guide at least partially disposable within the millable joint; and a cutting assembly configured to move alongside the guide until engaging with a sidewall of the millable joint. Further disclosed are various embodiments for methods of operating a downhole system having a millable joint. Further disclosed are various embodiments for a downhole deflector assembly, having a deflector securable within a main wellbore wherein an uphole end of the deflector comprises an angled face configured to direct one or more tubulars from the main bore to a lateral bore and a whipstock insert attachment detachably securable to the deflector.

What is claimed is: 
     
         1 . A downhole system comprising:
 a millable joint having a first portion shaped to extend into a main wellbore and a second portion shaped to extend into a lateral wellbore;   a cutting guide at least partially disposable within the millable joint; and   a cutting assembly configured to move alongside the cutting guide until engaging with a sidewall of the millable joint.   
     
     
         2 . The downhole system of  claim 1  further comprising:
 the cutting guide comprises 
 a lateral guide portion which is shaped to extend into the lateral wellbore and 
 a main guide portion which is shaped to extend into the main wellbore. 
 
     
     
         3 . The downhole system of  claim 1  further comprising:
 a guide surface on the cutting guide which is parallel to a central axis of the main wellbore. 
 
     
     
         4 . The downhole system of  claim 1  wherein:
 the sidewall of the millable joint is angled relative to a central axis of the main wellbore. 
 
     
     
         5 . The downhole system of  claim 1  wherein:
 the cutting guide is disposed within the first portion of the millable joint. 
 
     
     
         6 . The downhole system of  claim 1  wherein:
 the sidewall is positioned along a central axis of the main wellbore. 
 
     
     
         7 . The downhole system of  claim 1  further comprising:
 a fluted no-go centralizer placed within the millable joint. 
 
     
     
         8 . The downhole system of  claim 1  wherein:
 the sidewall of the millable joint is parallel to an angled face on a base deflector. 
 
     
     
         9 . A method for operating a downhole system comprising the steps of:
 removably securing a lateral liner running tool to a work string;   removably securing a millable joint as part of a liner string to the lateral liner running tool;   running the millable joint downhole via the work string until reaching a multi-lateral junction of more than one wellbore;   securing the millable joint in a position where a first portion of the millable joint is located within a main wellbore with a second portion of the millable joint located within a lateral wellbore;   disconnecting the lateral liner running tool from the liner including millable joint;   removably securing a cutting guide to a hydraulic locking tool;   running the cutting guide downhole via the work string until reaching the millable joint;   securing the cutting guide within the millable joint;   disconnecting the hydraulic locking tool from the cutting guide;   securing a cutting assembly to the hydraulic locking tool;   running the cutting assembly downhole via the work string until reaching a sidewall portion of the millable joint; and   removing the sidewall portion of the millable joint with the cutting assembly.   
     
     
         10 . The method of  claim 9  wherein:
 the step of removing the sidewall portion of the millable joint allows fluid communication through the millable joint. 
 
     
     
         11 . The method of  claim 9  wherein:
 the cutting guide directs the cutting assembly to move along a central axis of the main wellbore. 
 
     
     
         12 . The method of  claim 9  further comprising the step of:
 disposing a completion system within at least one wellbore extending from the multilateral junction. 
 
     
     
         13 . The method of  claim 9  further comprising the step of:
 disposing a dual leg junction completion system within two wellbores at the millable joint. 
 
     
     
         14 . The method of  claim 9  wherein:
 the cutting guide directs the cutting assembly within the millable joint to engage with said sidewall portion of the millable joint for removal. 
 
     
     
         15 . The method of  claim 9  wherein:
 the step of securing the cutting guide within the millable joint is performed by placing a lateral guide portion of the cutting guide within one wellbore at the multi-lateral junction. 
 
     
     
         16 . A downhole deflector assembly, comprising:
 a deflector securable within a main wellbore, wherein an uphole end of the deflector comprises an angled face configured to direct one or more tubulars from well bore to a lateral bore; and   a whipstock insert attachment detachably securable to the deflector, wherein the whipstock insert attachment at least partially covers the uphole end of the deflector, and wherein the whipstock insert attachment is configured to detach from the deflector in response to engagement with a hydraulic deployment and retrieval tool.   
     
     
         17 . The downhole deflector assembly of  claim 16  further comprising:
 a feature positioned on an inner surface of the whipstock insert attachment and sized to accept a portion of the hydraulic deployment and retrieval tool. 
 
     
     
         18 . The downhole deflector assembly of  claim 16  further comprising:
 a slot positioned on an inner surface of the whipstock insert attachment and sized to accept a portion of the hydraulic deployment and retrieval tool as a work string moves the hydraulic deployment and retrieval tool. 
 
     
     
         19 . The downhole deflector assembly of  claim 16  further comprising:
 a feature positioned on an inner surface of the deflector and sized to accept a portion of the whipstock insert attachment as a work string moves the hydraulic deployment and retrieval tool. 
 
     
     
         20 . The downhole deflector assembly of  claim 16  further comprising:
 a work string attached to the hydraulic deployment and retrieval tool; and 
 a pin which secures the whipstock insert attachment to the deflector; 
 wherein the pin shears off when an uphole force is applied to the hydraulic deployment and retrieval tool via the work string, allowing the whipstock insert attachment to be separated from the deflector.