Patent ID: 7445046
Filing Date: 2008-11-04
Classification: E21B

Abstract:
1. A wellhead assembly, comprising: a wellhead housing; an outer tubing hanger for securing to an outer string of tubing, the outer tubing hanger being landed in the wellhead housing, the outer tubing hanger having a production passage for receiving well fluid flowing up the outer string of tubing while in a first mode; and while in a second mode, an inner tubing hanger for securing to an inner string of tubing, the inner tubing hanger having a lower portion that is landed sealingly in the production passage of the outer tubing hanger, the inner tubing hanger having a production passage for receiving well fluid flowing up the inner string of tubing while in the second mode; a tree connected to the wellhead housing, the tree having a production passage; while in the first mode, an isolation tube extending from sealing engagement with the production passage of the outer tubing hanger to sealing engagement with the production passage of the tree; and while in the second mode, the isolation tube being removed and the inner tubing hanger having an upper portion extending into sealing engagement with the production passage of the tree.