Erosion-Resistant Multilateral Junctions

Abstract

A lateral junction for a multilateral wellbore having a main bore and a lateral leg which extends away from the main bore. The lateral junction includes a seal bore diverter and a hanger that is insertable into the seal bore diverter to form the junction. An engagement mechanism interlocks the hanger and seal bore diverter together at the crux of their joining.

What is claimed is: 
     
         1 . A lateral junction for a multilateral wellbore having a main bore and a lateral leg which extends away from the main bore, the junction comprising:
 a seal bore diverter to be inserted into the main bore, the seal bore diverter comprising a generally tubular body defining a central bore along its length;   an elongated window formed in the tubular body of the seal bore diverter;   a hanger to be landed within the central bore of the seal bore diverter to create the lateral junction, the hanger having a generally tubular body with a straight portion and a deviated portion which is shaped and sized to be disposed through the central bore of the seal bore diverter and exit through the elongated window; and   an engagement mechanism to interlock the hanger and seal bore diverter together.   
     
     
         2 . The lateral junction of  claim 1  wherein the engagement mechanism comprises:
 an engagement hook formed within the seal bore diverter and is shaped and sized to interlock with a complementary portion of the hanger. 
 
     
     
         3 . The lateral junction of  claim 1  wherein the engagement mechanism comprises:
 an engagement tab formed within the hanger and is shaped and sized to interlock with a complimentary portion of the seal bore diverter. 
 
     
     
         4 . The lateral junction of  claim 1  wherein:
 the seal bore diverter and hanger form a crux when the hanger is landed within the seal bore diverter; and 
 the engagement mechanism interlocks the hanger and seal bore diverter together at the crux. 
 
     
     
         5 . The lateral junction of  claim 3  further comprising:
 a first lateral window formed within the body of the hanger; 
 a second lateral window formed within the body of the hanger; and 
 the engagement tab being defined between the first and second lateral windows. 
 
     
     
         6 . A lateral junction of  claim 1  further comprising an orientation mechanism for angularly orienting the hanger within the seal bore diverter as the hanger is inserted into the seal bore diverter, the orientation mechanism comprising:
 an angled upper end surface on the seal bore diverter; 
 an orientation sleeve operably associated with the hanger, the orientation sleeve presenting a lower shoulder that is shaped and sized to be complementary to the angled upper end surface; and 
 wherein the hanger is angularly oriented within the seal bore diverter as the lower shoulder is brought into engaging contact with the angled upper end surface. 
 
     
     
         7 . A lateral junction for a multilateral wellbore having a main bore and a lateral leg which extends away from the main bore, the junction comprising:
 a seal bore diverter to be inserted into the main bore, the seal bore diverter comprising a generally tubular body defining a central bore along its length;   an elongated window formed in the tubular body of the seal bore diverter;   a hanger to be landed within the central bore of the seal bore diverter to create the lateral junction, the hanger having a generally tubular body with a straight portion and a deviated portion which is shaped and sized to be disposed through the central bore of the seal bore diverter and exit through the elongated window;   an engagement mechanism to interlock the hanger and seal bore diverter together; the seal bore diverter and hanger form a crux when the hanger is landed within the seal bore diverter; and   the engagement mechanism interlocks the hanger and seal bore diverter together at the crux.   
     
     
         8 . The lateral junction of  claim 7  wherein the engagement mechanism comprises:
 an engagement hook formed within the seal bore diverter and is shaped and sized to interlock with a complementary portion of the hanger. 
 
     
     
         9 . The lateral junction of  claim 7  wherein the engagement mechanism comprises:
 an engagement tab formed within the hanger and is shaped and sized to interlock with a complimentary portion of the seal bore diverter. 
 
     
     
         10 . The lateral junction of  claim 9  further comprising:
 a first lateral window formed within the body of the hanger; 
 a second lateral window formed within the body of the hanger; and 
 the engagement tab being defined between the first and second lateral windows. 
 
     
     
         11 . The lateral junction of  claim 7  further comprising an orientation mechanism for angularly orienting the hanger within the seal bore diverter as the hanger is inserted into the seal bore diverter, the orientation mechanism comprising:
 an angled upper end surface on the seal bore diverter; 
 an orientation sleeve operably associated with the hanger, the orientation sleeve presenting a lower shoulder that is shaped and sized to be complementary to the angled upper end surface; and 
 wherein the hanger is angularly oriented within the seal bore diverter as the lower shoulder is brought into engaging contact with the angled upper end surface. 
 
     
     
         12 . A method of forming a lateral junction within a multilateral wellbore having a main bore and a lateral leg which extends away from the main bore, the method comprising the steps of:
 disposing a seal bore diverter within the main bore of the wellbore, the seal bore diverter having a generally tubular body defining a central bore along its length and an elongated window formed within the body;   inserting a hanger into the central bore of the seal bore diverter, the hanger having a generally tubular body with a straight portion and a deviated portion which is shaped and sized to be disposed through the central bore of the seal bore diverter and exit through the elongated window;   causing the deviated portion of the hanger to exit the seal bore diverter through the elongated window, a crux being formed between the deviated portion of the hanger and the body of the seal bore diverter; and   forming an interlocking engagement between the hanger and the seal bore diverter at the crux.   
     
     
         13 . The method of  claim 12  further comprising the step of angularly orienting the hanger with respect to the seal bore diverter as the hanger is inserted into the central bore of the seal bore diverter. 
     
     
         14 . The method of  claim 12  wherein the step of forming an interlocking engagement further comprises engaging an engagement hook formed within the seal bore diverter with an engagement tab formed within the seal bore diverter.