摘要 |
A well cleanup and completion apparatus and technique. A packer is located downhole in a borehole, and a tool string comprising a one-way vent assembly and a one-way circulating valve assembly is connected above a perforating gun. The tool string is used to run the gun downhole through the packer until the gun arrives at a location adjacent to the formation to be perforated. During this time, the packer assembly must be in a configuration which admits flow from the lower to the upper annulus. Cleaning fluid is circulated down the entire tool string to the one-way circulating valve assembly located immediately above the firing head of the gun, thereby displacing fluid from the lower annulus, and cleaning any debris from the gun firing head. The packer is next closed, the gun detonated, whereupon the formation is perforated and production fluid flows through the perforations, up the lower annulus, into the one-way vent assembly located below the packer, into the tubing, and to the surface of the ground. Accordingly, the apparatus enables the gun and the borehole annulus adjacent the gun to be cleaned, thereby assuring that the well is properly completed in a single trip into the wellbore.
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