초록

A blast joint and related handling apparatus and method for installing the blast joint in a pressurized well, using a snubber unit. The blast joint has a pressure rated protective jacket, a pressure operated ring load compensator, and an adjustable tubing anchor.

대표청구항 ▼

A blast joint apparatus for insertion into a well through a snubber unit, comprising: a production tube; a concentric sub attached to a lower end of the production tube, threaded for connection to production tubing in the well; erosion resistant rings on the outer surface of the production tube, sta

A blast joint apparatus for insertion into a well through a snubber unit, comprising: a production tube; a concentric sub attached to a lower end of the production tube, threaded for connection to production tubing in the well; erosion resistant rings on the outer surface of the production tube, stacked upwardly from the concentric sub; a pressure jacket attached at a lower end thereof to the concentric sub and extending upwardly along the production tube outside the erosion resistant rings; first support means attached to an upper end of the production tube, to support the production tube; second support means attached to an upper end of the pressure jacket, to support the pressure jacket; third support means attached to the erosion resistant rings, to support the erosion resistant rings; anchor means for preventing relative vertical movement between the erosion resistant rings and the production tube; and load compensating means for maintaining a vertical load on the erosion resistant rings to prevent separations between rings. A method for attaching a blast joint to installed production tubing and inserting the blast joint into a well through snubber unit, comprising the steps of: assembling a first length of a blast joint having a first length of production tube, a concentric sub attached to a lower end of the production tube, a first set of erosion-resistant rings stacked vertically on the outside of the production tube, and a first length of pressure jacket extending vertically outside the erosion-resistant rings; attaching the first length of blast joint to a lifting means which independently supports the first length of production tube, the first length of pressure jacket, and the first set of erosion-resistant rings, so that the tube, the jacket, and the rings can move vertically independently and swivel independently about a vertical axis; lifting the first length of blast joint to a vertical position such that a lower end of the first set of erosion resistant rings is above a lower end of the first length of production tube, and a lower end of the first length of pressure jacket is above the lower end of the first set of erosion-resistant rings; threading the concentric sub into the installed production tubing which protrudes from the snubber unit; lowering the lifting means until the first set of erosion-resistant rings rests upon the concentric sub; releasing the erosion-resistant rings from the lifting means; further lowering the lifting means until the first length of pressure jacket contacts the concentric sub; threading the first length of pressure jacket onto the concentric sub; snubbing the first length of blast joint into the well; and releasing the pressure jacket and the production tube from the lifting means.