US Patent 8127857 Single trip, tension set, metal-to-metal sealing, internal lockdown tubing hanger

A system, apparatus, and method to apply tension to completion tubing in a wellbore. The system, apparatus, and method comprises an inner and outer tubing hanger, with the string of tubing attached to the inner tubing hanger. A running tool lands the outer tubing hanger on a landing shoulder and continues to lower the inner tubing hanger into the wellbore until the lower end of the inner tubing hanger latches into a retaining device. The running tool then sets a seal which holds the outer tubing hanger in position and causes a ratcheting mechanism to move to an engaged position. The running tool then withdraws the inner tubing hanger a predetermined distance until the inner tubing hanger engages the ratcheting mechanism.