HIGH TEMPERATURE, HIGH PRESSURE RETRIEVABLE PACKER

摘要

In a retrievable packer adapted for service under high temperature and high pressure operating conditions, improved retention of the packer in the wellbore is achieved by use of an inventive slip/wedge system, wherein the cones on the wedges are spaced a progressively slightly greater distance apart from their corresponding slip cones, from the centermost slip cone to the outermost slip cone. This forces the center of the slip to be loaded first. As greater forces are exerted on the wedges from end to end, the wedge will deform slightly and the next cone of the wedge will make contact with its matching portion of slip. Thereby, as the wedges are loaded higher and higher, more wedge cones come into bearing contact with the slip. Further, a barrel slip is used, to provide a uniform circumferential distribution of forces. This design effectively allows initial setting of the packer with very little slip tooth contact area. This permits the slip to quickly get a good grip into the casing wall. Subsequent higher loading brings more and more slip teeth to bear and prevents overstressing the casing.