Abstract: The downhole flow control means or downhole blowout preventor (downhole BOP) of the present invention is adapted for use during reverse circulation drilling with both concentric drill pipe and concentric coiled tubing. The downhole BOP comprises an inner tube member having an inner passage therethrough and an outer casing forming an annular passage between the inner tube member and the outer casing. The inner passage and the annular passage of the downhole BOP is in fluid communication with the inner passage and annular passage, respectively, of the concentric drill pipe or concentric coiled tubing. The downhole BOP further comprises two valve means, preferably a check valve and a ball valve, for closing off the annular passage and the inner passage of the downhole BOP, respectively. In a preferred embodiment, the downhole BOP further comprises an electric actuator for opening and closing the ball valve.

Abstract: A cementing apparatus for use in cementing operations using concentric tubing or drill string such as concentric drill pipe, concentric coiled tubing, and the like is provided having an isolation cementing tool and a cementing flow control means. Concentric tubing or drill string adapted for use in cementing a well is further disclosed. A method for cementing a well using concentric tubing or drill string is also provided.

Abstract: The downhole flow control means or downhole blowout preventor (downhole BOP) of the present invention is adapted for use during reverse circulation drilling with both concentric drill pipe and concentric coiled tubing. The downhole BOP comprises an inner tube member having an inner passage therethrough and an outer casing forming an annular passage between the inner tube member and the outer casing. The inner passage and the annular passage of the downhole BOP is in fluid communication with the inner passage and annular passage, respectively, of the concentric drill pipe or concentric coiled tubing. The downhole BOP further comprises two valve means, preferably a check valve and a ball valve, for closing off the annular passage and the inner passage of the downhole BOP, respectively. In a preferred embodiment, the downhole BOP further comprises an electric actuator for opening and closing the ball valve.

Abstract: An isolation tool for use with a concentric drill string for isolating a zone in a wellbore for testing is provided comprising a center tube and an outer casing forming an annular conduit therebetween and an expandable and contractible packer for sealing off an outside annular passage formed between a wall of the wellbore and an outer surface of the concentric drill string, whereby the isolation tool is adapted to be operably connected to the concentric drill string such that the isolation tool is in fluid communication with the concentric drill string.

Abstract: A zone isolating and testing apparatus comprising an isolation tool and a downhole flow control means and a method of using such apparatus. The zone isolating and testing apparatus is particularly useful for testing zones during reverse circulation drilling using concentric drill string such as concentric drill pipe or concentric coiled tubing. The isolation tool of the zone isolating and testing apparatus comprises an expandable packer means and is adapted to connect to concentric drill string near the drilling means and be in fluid communication with the concentric drill string. The downhole flow control means of the zone isolating and testing apparatus comprises at least two valves, one for closing off the annular conduit between the inner tube and outer tube of the concentric drill string and the other for closing off the inner conduit of the inner tube.

Abstract: A cementing apparatus for use in cementing operations using concentric tubing or drill string such as concentric drill pipe, concentric coiled tubing, and the like is provided having an isolation cementing tool and a cementing flow control means. Concentric tubing or drill string adapted for use in cementing a well is further disclosed. A method for cementing a well using concentric tubing or drill string is also provided.

Abstract: Method and apparatus for drilling a directional or horizontal wellbore in a hydrocarbon formation using concentric drill string having an inner pipe and an outer pipe defining an annulus there between. A bottomhole assembly comprising a directional drilling means such as an air hammer or a rotary drill bit and driving system is provide at the lower end of the concentric drill string and drilling medium is delivered through the annulus or inner pipe for operating the directional drilling means to form a borehole. Exhaust drilling medium, drilling cutting and hydrocarbon are removed from the wellbore by extracting the exhaust drilling medium, drilling cutting and hydrocarbon through the other of the annulus or inner pipe.

Abstract: An apparatus and method for cementing a well using concentric drill string, e.g., concentric drill pipe, concentric coiled tubing and the like is disclosed. Concentric drill string comprises an inner string and an outer string, forming an annular conduit therebetween. Cementing apparatus comprises an isolation cementing tool and a cementing flow control means. The isolation cementing tool has a center tube and an outer casing forming an annular conduit therebetween, and an expandable packer means surrounding the outer casing. The cementing flow control means has a center tube and an outer casing forming an annular conduit therebetween, and a plurality of check valves positioned in either the center tube, within the annular conduit between the inner tube and the outer casing, or both.

Abstract: Method and apparatus for drilling a directional or horizontal wellbore in a hydrocarbon formation using concentric coiled tubing drill string having an inner coiled tubing string and an outer coiled tubing string defining an annulus there between. A bottomhole assembly comprising a directional drilling means is provided at the lower end of the concentric coiled tubing drill string for reverse circulation drilling. Directional drilling means comprises a reciprocating air hammer and a drill bit, a positive displacement motor and a reverse circulating drill bit, or a reverse circulating mud motor and a rotary drill bit, and a bent sub or housing. Drilling medium is delivered through the annulus or inner coiled tubing string for operating the directional drilling means to form the directional or horizontal wellbore. Exhaust drilling medium comprising drilling medium, drilling cuttings and hydrocarbons are removed from the wellbore by extraction through the other of the annulus or inner coiled tubing string.

Abstract: A casing degasser tool (CDT) is provided which is adapted to be inserted into production piping such as casing, slotted liners, or production tubing for use during well completion. The CDT comprises a body having a top end, a bottom end and an outer surface, at least one sealing element surrounding a portion of the outer surface of the body and a connection means located at or near the top end of the body for connecting a wire line or other pulling device to the CDT to assist in positioning the CDT within the production piping and for pulling the CDT through the length of the production piping. The CDT can be used when adding joints of production piping to prevent hydrocarbons from flowing to the surface of the well.

Abstract: A zone isolating and testing apparatus comprising an isolation tool and a downhole flow control means and a method of using such apparatus is disclosed. The zone isolating and testing apparatus is particularly useful for testing zones during reverse circulation drilling using concentric drill string such as concentric drill pipe or concentric coiled tubing. The isolation tool of the zone isolating and testing apparatus comprises an expandable packer means and is adapted to connect to concentric drill string near the drilling means and be in fluid communication with the concentric drill string. The downhole flow control means of the zone isolating and testing apparatus comprises at least two valves, one for closing off the annular conduit between the inner tube and outer tube of the concentric drill string and the other for closing off the inner conduit of the inner tube.

Abstract: The downhole flow control means or downhole blowout preventor (downhole BOP) of the present invention is adapted for use during reverse circulation drilling with both concentric drill pipe and concentric coiled tubing. The downhole BOP comprises an inner tube member having an inner passage therethrough and an outer casing forming an annular passage between the inner tube member and the outer casing. The inner passage and the annular passage of the downhole BOP is in fluid communication with the inner passage and annular passage, respectively, of the concentric drill pipe or concentric coiled tubing. The downhole BOP further comprises two valve means, preferably a check valve and a ball valve, for closing off the annular passage and the inner passage of the downhole BOP, respectively. In a preferred embodiment, the downhole BOP further comprises an electric actuator for opening and closing the ball valve.

Abstract: A zone isolating and testing apparatus comprising an isolation tool and a downhole flow control means and a method of using such apparatus is disclosed. The zone isolating and testing apparatus is particularly useful for testing zones during reverse circulation drilling using concentric drill string such as concentric drill pipe or concentric coiled tubing. The isolation tool of the zone isolating and testing apparatus comprises an expandable packer means and is adapted to connect to concentric drill string near the drilling means. The downhole flow control means of the zone isolating and testing apparatus comprises two valves, one for closing off the annulus between the inner tube and outer tube of the concentric drill string and the other for closing off the inner space of the inner tube. The downhole flow control means is also adapted to connect to concentric drill string near the drilling means.

Abstract: Method and apparatus for drilling a well bore in a hydrocarbon formation using concentric drill string having an inner pipe and an outer pipe defining an annulus there between. A drilling means such as an air hammer or a rotary drill bit and driving system is provide at the lower end of the concentric drill string and drilling medium is delivered through the annulus or inner pipe for operating the drilling means to form a borehole. Drilling medium, drilling cutting and hydrocarbon are removed from the well bore by extracting the drilling medium, drilling cutting and hydrocarbon through the other of the annulus or inner pipe.