An expandable threaded tubular connection

Abstract From the Canadian patent

An expandable threaded connection between segments of expandable tubulars that provides a high bearing pressure seal at a specific area along the pin and box members is , disclosed. The invention utilizes first and second "grooves" in a surface of the box member , and corresponding first and second "ribs" on the pin nose. The radial expansion of the , tubulars causes the pin to become shorter in length thereby causing the pin , nose to retract from the back of the box member. As the pin nose retracts a high bearing , pressure, metal-, to-metal seal is formed between elements of the mating tubulars.