Patent ID: 7191844

Claim:
A method for controlling inflation and deflation of spaced inflatable packer elements of a tubing conveyed straddle stimulation tool within a well casing of a well, the straddle stimulation tool having a packer pressure control member therein being moveable responsive to tubing pressure and casing pressure and being moveable by predetermined tubing applied tension force, said method comprising: developing packer element inflation pressure within said straddle stimulation tool with tubing pressure and inflating the spaced inflatable packer elements for sealing thereof within the well casing and defining an isolated casing interval; causing tubing pressure responsive positioning of said packer pressure control member for maintaining inflation of the spaced inflatable packer elements; injecting well stimulation fluid through said straddle stimulation tool and into the isolated casing interval; after completion of well stimulation, applying sufficient tension force to said straddle stimulation tool via the tubing for moving said packer pressure control member by tubing applied tension force and releasing inflation pressure from the spaced inflatable packer elements and freeing said straddle stimulation tool for tubing conveyance within the well casing; disposing a spring member in force transmitting relation between a deflate shifter member and said straddle stimulation tool to urge said deflate shifter member in a direction opposing said pulling force, said tubing being able to apply a pulling force to said packer element pressure control member only after having overcome the force of said spring member; and applying sufficient pulling force to said inflate shifter member via the tubing string to overcome the force of said spring member and move said packer element pressure control member to said packer element deflate position.