Abstract: The present invention provides for a valve in a tubing string that allows the tubing string to fill with well fluids as the string is assembled and lowered into a well bore, but can be used to check pressure integrity of the tubing string during various stages of the assembly.

Abstract: A method for evaluating the permeability and formation damage in the porous rock around a well bore. This method relates to the use of a single string coiled tubing and a down hole assembly which includes a microcontroller, an electrically operable fluid control valve and electrically operable pressure sensing devices which allow for real time pressure transient analysis techniques before, during and after formation stimulation treatments.

Abstract: A method for evaluating the permeability and formation damage in the porous rock around a well bore. This method relates to the use of a single string coiled tubing and a down hole assembly which includes a microcontroller, an electrically operable fluid control valve and electrically operable pressure sensing devices which allow for real time pressure transient analysis techniques before, during and after formation stimulation treatments.

Abstract: A method of removing formation damage through the controlled injection of fluids into the formation, followed by a controlled sudden release of pressure in the formation, an under-balanced surge, which causes fluid and damaging materials to flow back into the well bore. This method is most effective when repeated more than once.

Abstract: A method of removing formation damage through the controlled injection of fluids into the formation, followed by a controlled sudden release of pressure in the formation, an under-balanced surge, which causes fluid and damaging materials to flow back into the well bore. This method is most effective when repeated more than once.

Abstract: A method of removing formation damage through the controlled injection of fluids into the formation, followed by a controlled sudden release of pressure in the formation, an under-balanced surge, which causes fluid and damaging materials to flow back into the well bore. This method is most effective when repeated more than once.

Abstract: Dewaxing control apparatus is adapted for use in a well casing containing a production tubing string defining an annulus within the well casing and a down hole pump which pumps oil upwardly through the production tubing. The apparatus has a housing adapted to be installed in-line with the production tubing. A passage in the housing places the annulus in communication with the interior of the production tubing for purposes of circulating a hot dewaxing oil. A cup packer positioned below the passage closes the annulus against downward liquid flows. A gas by-pass passage in the housing permits gases to be exhausted upwardly through the annulus during oil production despite the presence of the packer. A valve mechanism responsive to pressure developed by pumping hot dewaxing oil down the annulus closes the gas by-pass passage and opens the liquid transfer passage so that the dewaxing oil can flow into the production tubing and back up to the surface.

Abstract: A drill stem testing system which does not require rotation or axial displacement of an associated drill string to actuate valves and pumps is described. The system includes a drill stem constructed in a number of sections which are interconnected with screw-type connections. The housing contains test-related devices such as a pump for inflating packers with wellbore fluids to isolate a test region, a packer deflation valve for exhausting fluids from the packers when testing is complete, a test flow valve for introducing wellbore test flows into the housing, and a pressure equalization valve for placing the test region in communication with external wellbore regions prior to packer deflation. Each of these devices is adapted for electric actuation and contacts an internal power line extending centrally through the interior of the housing.