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A retrievable bridge plug having an internal bypass passage and external retrieving lugs, and a retrieving tool therefor. When the bypass passage is sealed, both the top and bottom openings of the bypass passage are closed, preventing debris from entering the bypass passage through either opening. A

A retrievable bridge plug having an internal bypass passage and external retrieving lugs, and a retrieving tool therefor. When the bypass passage is sealed, both the top and bottom openings of the bypass passage are closed, preventing debris from entering the bypass passage through either opening. A directing shroud is provided adjacent the top opening of the bypass passage, such that when the bypass passage is opened, part of any fluid flowing uphole through the bypass passage is directed over the retrieving lugs, clearing them of any debris and facilitating latching by the retrieving tool. The shroud also prevents debris from packing around the top opening of the bypass passage. A retrieving tool is also provided, which retrieving tool, through cooperation of a sleeve having a "J" shaped slot, and an inner latch sleeve having a straight slot, locks the retrieving tool onto the retrieving lugs.

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[ What is claimed is:] [1.]1. A retrieving tool having top and bottom ends, for retrieving downhole tools from a well bore, such downhole tools having a top end and a plurality of transversely extending retrieving lugs, the retrieving tool comprising:(a) a tubing attachment interface for detachably

[ What is claimed is:] [1.]1. A retrieving tool having top and bottom ends, for retrieving downhole tools from a well bore, such downhole tools having a top end and a plurality of transversely extending retrieving lugs, the retrieving tool comprising:(a) a tubing attachment interface for detachably attaching the retrieving tool to tubing;(b) a retrieving lug guide having a bottom end, said retrieving lug guide comprising a sleeve defining a plurality of J-shaped slots extending upward from its bottom end, the number of said J-shaped slots being equal to or greater than the number of retrieving lugs on the downhole tool and, each of said J-shaped slots being sized to accommodate a retrieving lug, each J-shaped slot having a stem portion and a hook portion, said stem portion of each J-shaped slot extending upward and obliquely from said bottom end of the retrieving lug guide, said hook portion of each J-shaped slot extending downward, said bottom end of said retrieving lug guide being provided with downward-pointing spade-shaped profiles between entrances to each J-shaped slot;(c) a latch sleeve mounted for reciprocal longitudinal movement within the retrieving tool, said latch sleeve having a bottom end, at least a portion of said latch sleeve overlapping a sufficient portion of said retrieving lug guide so as to substantially overlap an interface between the hook portion and stem portion of the J-shaped slots of said retrieving lug guide; said latch sleeve defining a plurality of latch slots extending upward from the bottom end of said latch sleeve, the number of said latch slots being equal to or greater than the number of retrieving lugs, said latch slots being sized to accommodate the retrieving lugs, said latch slots being aligned with the hook portions of the J-shaped slots of the retrieving lug guide;(d) each of said retrieving lug guide and latch sleeve having an inner diameter large enough to allow the retrieving lug guide and latch sleeve to pass over all portions of the downhole tool above the retrieving lugs, but small enough to cause engagement with the retrieving lugs;(e) a latch sleeve alignment mechanism to prevent the latch sleeve from rotating relative to the retrieving lug guide;(f) a latch sleeve biasing element to bias the latch sleeve downward relative to the retrieving lug guide; and(g) a rotation mechanism to allow the retrieving lug guide, latch sleeve, latch sleeve alignment mechanism and biasing element to rotate relative to the tubing attachment interface, reby as the retrieving tool is lowered into the well on the end of the tubing, the retrieving lugs on the downhole tool first contact the bottom end of the retrieving lug guide, the spade-shaped profile of the bottom end of the retrieving tool guide causing the retrieving tool guide, latch sleeve, latch sleeve alignment mechanism and biasing element to rotate relative to the tubing attachment interface as the retrieving tool is lowered further, still further lowering causing the retrieving lugs to enter the stem portions of the J-shaped slots and then to bear against the bottom end of the latch sleeve causing the latch sleeve to move upwards against the biasing force provided by the biasing element, further downward movement of the retrieving tool causing the retrieving lugs to enter the hook portion of the J-shaped slots allowing the biasing element to force and retain the latch sleeve back down relative to the retrieving lug guide as the retrieving lugs enter the latch slots, thereby locking the retrieving lugs within the hook portion of the J-shaped slots of the retrieving lug guide.