Hydraulically set packer useful with independently set straddle packers including an inflate/deflate valve and a hydraulic ratchet associated with the straddle packers

摘要

A novel hydraulic set packer is set independently of the setting of two other straddle packers, the straddle packers being set by other than hydraulic means, such as by inflation or compression. If the straddle packers are set by inflation, a novel inflate deflate valve is associated with both straddle packers for providing an additional method to deflate the inflatably set straddle packer. If the straddle packers are compression set, it may be necessary to allow a top staddle packer to set only after the bottom straddle packer is already set, that is, the top straddle packer is not permitted to set when the straddle packer assembly is being pushed into a deviated/horizontal borehole or through a restriction in the borehole. Accordingly, a novel hydraulic ratchet, disposed above a bottom straddle packer on a tubing but below the top straddle packer on the tubing, will enable the top straddle packer to set only after the bottom straddle packer is already set.