Patent ID: 7578342

Claim:
A method of deploying a pair of spaced-apart inflatable packers carried about a mandrel disposed in a borehole penetrating a subsurface formation, comprising the steps of: pressurizing the packers so as to isolate an annular portion of the borehole wall; collecting one or more samples of formation fluid via the isolated portion of the borehole wall; depressurizing the packers so as to permit movement of the mandrel within the borehole; and restricting deformation of the packers during the pressurizing step using an annular bracing assembly; wherein each packer comprises: an expandable tubular element having a pair of ends; and a pair of annular end supports for securing the respective ends of the tubular element about the mandrel, one of the end supports being movable and the other end support being fixed with respect to the mandrel, the movable end support being equipped with an inwardly-facing surface area that exceeds its outwardly-facing surface area, whereby borehole fluid pressure imposes a net force that moves the movable end support outwardly when the first tubular element is depressurized and contracted.