Abstract: A self-locating reentry system is provided to allow reliable reentry from a primary wellbore into one or more secondary wellbores. The reentry system may include one or more self-locating assemblies which may be engaged with selected portions of a lateral opening disposed between the primary wellbore and a respective secondary wellbore. Each self-locating assembly and respective key or lug cooperate with each other to provide optimum location and alignment relative to the lateral opening for communication of well tools and smaller diameter tubing strings between the primary wellbore and the associated secondary wellbore. A retaining mechanism is preferably provided to maintain the locator lug or key in its first retracted position until the reentry system is at a desired downhole location relative to the selected lateral opening.

Abstract: A chemical injection assembly and apparatus for treating production fluids in a bore-hole. The system includes a fixed packer having an opening passing therethrough for receiving a production tubing string, a closable orifice in the packer that is actuated by the tubing string and appropriate seals for preventing fluid transfer within the packer. When the tubing string is inserted into the packer, a collar on the tubing string engages a shiftable sleeve that places an orifice in the shifting sleeve in alignment with the orifice in the injection sleeve so that chemical treatment fluid from the surface can be forced down the bore-hole casing through the closable orifice in the packer and into the production fluid at the perforations near the producing formations. The treated fluids then enter the tail pipe of the packer and up the tubing string to the surface. When it is desired to plug the well, a plug is inserted into the tail pipe and the tubing string is withdrawn.

Abstract: In a wellbore having a liner hung from a higher string of pipe, a permanent packer and a seal unit are utilized to isolate the annulus between the liner and the wellbore surface. The downhole completion assembly, which comprises an on-off tool, a latch and seal assembly and a tailpipe, can be lowered into the packer and seal unit by the production tubing, with the latch mechanism of the latch and seal assembly snapping into a threaded portion of the packer. The on-off tool can be disconnected and the production tubing withdrawn from the well. Alternatively, the latch mechanism can be disengaged and the entire downhole completion assembly can be withdrawn from the well in a single trip.