Abstract: A downhole tool apparatus (34) including a housing (42) adapted to be connected in a pipe string (30), the housing (42) having a generally cylindrical bore (44) defined therein, an operating assembly (112) disposed within the cylindrical bore (44) of the housing (42) having open and closed positions and a mandrel (142) slidably received in the cylindrical bore (44) of the housing (42) and adapted to be selectively telescoped between first and second axial positions relative to the housing (42) to manipulate the operating assembly (112) and selectively rotated between first and second circumferential positions relative to the housing (42) to selectively lock the mandrel (142) in an axial position relative to the housing (42).

Abstract: A travel joint provides economical manufacture, installation, service, and operation thereof. The travel joint substantially reduces the number of parts potentially exposed to corrosive fluid, eliminates cavities wherein such corrosive fluid may become trapped, and substantially reduces the number of dynamic and static seals required for its operation. Additionally, a torque transmitting member is utilized to prevent torquing through threaded service breaks in the travel joint. In a preferred embodiment, a travel joint has a tubular upper case, a torque collar rotationally and axially coupled to the upper case, a tubular mandrel axially slidably received in the upper case and torque collar, and rotationally coupled to the torque collar, and an adapter which axially and radially inwardly retains the torque collar.

Abstract: A downhole tool for early formation evaluation is disclosed. The tool comprising a housing having a fluid passageway and a mandrel having an interior volume. The mandrel is slidably disposed within the housing and has a plurality of axial positions relative to the housing. The mandrel is slidably operated responsive to the fluid pressure within the interior volume such that the mandrel cycles through said plurality of positions. A retractor sleeve is operably associated with the housing and the mandrel for engaging the mandrel and slidably urging the mandrel relative to the housing. The retractor sleeve is slidably operated responsive to the fluid pressure within the interior volume. A seal assembly is slidably disposed around the housing. The seal assembly includes a floating piston.

Abstract: An automatic downhole pump assembly comprising a housing, a sleeve slidably disposed within the housing, a piston defining an interior volume, the piston slidably disposed within the sleeve and within the housing such that a fluid pressure within the interior volume causes the sleeve to oscillate relative to the housing and causes the piston to oscillate relative to the sleeve and the housing, and a pump which is operably associated with the piston such that fluid is pumped through the pump assembly as the piston oscillates relative to the housing.

Abstract: A formation testing system provides the ability to reliably and repeatedly perform tests, such as drawdown tests, on closely spaced apart formations intersected by subterranean wellbores without relying on absolute fluid pressure for actuation thereof. In a preferred embodiment, a formation testing system is alternately configured for normal drilling operations or for fluid sampling operations by applying preselected differential pressures to the system. In a representatively illustrated preferred embodiment, a formation testing system has opposing pistons which cooperate with uniquely configured ratchet mechanisms to change the system's configuration in response to changes in differential pressure applied thereto.

Abstract: An apparatus for loading fluid into subterranean formations includes a housing, a sleeve slidably disposed within the housing, a piston defining an interior volume, the piston slidably disposed within the sleeve and within the housing such that a fluid pressure within the interior volume causes the sleeve to oscillate relative to the housing and causes the piston to oscillate relative to the sleeve and the housing, and a pump which is operably associated with the piston such that the fluid pressure from the interior volume is intensified in the pump and injected into the formation as the piston oscillates relative to the housing.

Abstract: A well tool apparatus (40) comprising a tubular housing (56) and operating mandrel (58) each having autofill ports (74, 76) and bypass ports (128, 130) therein. The well tool apparatus (40) also comprising a normally closed ball valve (96) rotatably disposed within the operating mandrel (58) preventing communication between the upper section (104) and the lower section (106) of the operating mandrel (58) such that internal pressure above the ball valve (96) greater than internal pressure below the ball valve (96) downwardly urges the operating mandrel (58) allowing pressure testing of the pipe string (32) above the ball valve (96) and such that internal pressure below the ball valve (96) greater than internal pressure above ball valve (96) upwardly urges the operating mandrel (58).

Abstract: Early evaluation testing of a subsurface formation is provided by monitoring pressure fall-off in the formation. This is accomplished by providing a column of fluid in the well having an overbalanced, hydrostatic pressure at the subsurface formation greater than a natural formation pressure of the subsurface formation. A testing string is run into the well, and the testing string includes a packer, a pressure monitor and a closure tool arranged to close a bore of the testing string. The formation is shut in by setting the packer and closing the bore of the testing string with the closure tool and thereby initially trapping the overbalanced hydrostatic pressure of the column of fluid in the well below the packer. Then the pressure in the well below the packer is monitored as it falls off toward the natural formation pressure. This data can be extrapolated to estimate the natural formation pressure based upon a relatively short actual test interval on the order of ten to fifteen minutes.

Abstract: A number of improvements are provided in early evaluation systems which can be utilized to test and/or treat a subsurface formation intersected by an open uncased borehole. An outer tubing string is run into the well and has a packer which is set in the open, uncased borehole above the subsurface formation of interest. An inflation passage is provided and preferably has an inflation valve associated therewith which is operated by manipulation of the tubing string. A communication passage communicates the interior of the outer tubing string with the borehole below the packer. An inner well tool is run into the outer tubing string and engaged therewith, whereupon it is placed in fluid communication with the subsurface formation to either sample the formation or treat the formation. Preferably, a circulating valve is provided above the packer to allow fluid circulation in the well annulus during the testing procedure to prevent differential sticking of the outer tubing string.

Abstract: A sample draining apparatus includes a hydraulic circuit having a sampler vessel and a drain vessel disposed therein. A first pump is located outside the hydraulic circuit and pumps fluid from a fluid source outside the hydraulic circuit into the hydraulic circuit to pressurize the circuit. A second pump is disposed in the hydraulic circuit for circulating fluid in the hydraulic circuit so that a fluid sample flows from the sampler vessel into the drain vessel while the sample is maintained within the closed hydraulic circuit.

Abstract: A pressure test and bypass valve for use in well testing. The apparatus comprises a housing defining a central opening therein and a mandrel slidably disposed in the central opening. A ball valve allows fluid flow through the central opening when in an open position and prevents fluid flow therethrough when in a closed position. A sleeve valve allows communication between the central opening and a well annulus when in an open position and prevents communication between the central opening and the well annulus when in a closed position. The ball valve and sleeve valve are actuated substantially simultaneously in response to well annulus pressure. A rupture disc is ruptured due to differential pressure thereacross. This allows well annulus pressure to act across a differential area on the mandrel such that the mandrel is moved relative to the housing, thereby actuating the valves.

Abstract: The present invention provides an apparatus and method for testing a subterranean formation. The inventive apparatus comprises an internal-external differential pressure operated circulation tool, an external pressure operated drill stem testing tool, and an external pressure operated formation testing tool. The drill stem testing tool is positioned in the inventive apparatus beneath the circulation tool and the formation testing tool is positioned in the apparatus beneath the drill stem testing tool. In the method of the present invention, a testing string comprising the inventive apparatus is run into a well bore.

Abstract: A sample draining apparatus includes a hydraulic circuit having a sampler vessel and a drain vessel disposed therein. A first pump is located outside the hydraulic circuit and pumps fluid from a fluid source outside the hydraulic circuit into the hydraulic circuit to pressurize the circuit. A second pump is disposed in the hydraulic circuit for circulating fluid in the hydraulic circuit so that a fluid sample flows from the sampler vessel into the drain vessel while the sample is maintained within the closed hydraulic circuit.

Abstract: An electric coupling for two electric circuits in a well includes an electric contact and a contact receiver connected to respective ones of the circuits so that a contact/receiver pair is formed when the contact and receiver are moved together The receiver is sealed by a sealing member. The sealing member is disposed so that it is penetrated by the contact when the contact and receiver are moved together. A coupling including two such pairs is preferably used to connect two electric wires in the well to form a current conductive loop linking two electric coils. One of the coils is adapted to be moved in the well relative to the other coil which is adapted to be fixed in the well. In a preferred embodiment, one coil is on a wireline tool and the other coil is on a downhole tool.

Abstract: A bypass valve for bypassing well fluids, and method of use thereof. The valve comprises a tubular housing defining a bypass port therethrough with an inner sleeve mandrel defining a bypass port initially aligned with the bypass port in the housing. The valve also comprises a power mandrel slidably disposed within the housing such that, as weight is set down on the power mandrel, pressure is increased in a first oil chamber which has a rupture disc in communiction therewith. When the pressure reaches a predetermined level, the rupture disc ruptures so that the oil chamber is emptied into the well annulus. This allows the power mandrel to move and strike an operating mandrel which is also slidably disposed in the housing. The jarring force shears a shear pin which allows the operating mandrel to move a floating piston disposed in a second oil chamber. A metering cartridge restricts flow of fluid out of the second metering chamber, thereby providing a time delay for movement of the operating mandrel.

Abstract: Well tools are provided which although pressure responsive, may be maintained by a hydraulic lockout in a nonresponsive condition until a threshold actuation step is performed. This lockout may be achieved by a hydraulic mechanism which allows pressure to be stored in a fluid spring during periods of increased pressure at the pressure source, and which traps these pressures even when pressure at the pressure source is reduced. When the tool is desired to be responsive to pressure cycles, a valve may be opened communicating the pressure in the fluid spring to a movable member in the well tool. This differential may be established by a differential between the pressure in the fluid spring and the pressure source. Communication of pressure in the fluid spring to a movable mandrel will then allow operation of the well tool in response to pressure cycles at the pressure source in accordance with the established design of the well tool.

Abstract: An annulus pressure responsive well tool includes a selectively actuatable hydraulic bypass for bypassing a pressure differential across a power piston of the tool so that an operating element associated with the power piston will remain in a chosen position during a subsequent change in well annulus pressure.

Abstract: A well testing apparatus includes a housing having a formation fluid flow passage. A sliding sleeve tester valve is reciprocably disposed in the housing. A probe separable from the housing and constructed to be received coaxially within the sliding sleeve tester valve has a probe passage defined therethrough for communicating the formation fluid flow passage with a measuring device carried on the probe. A probe valve is also disposed in the housing and is constructed to receive a lower end of the probe. A releasable connector operably connects the probe and the sliding sleeve tester valve so that the sliding sleeve tester valve is moved between its open and closed positions in response to reciprocal movement of the probe relative to the housing. The tester valve can be operated an indefinite number of times, and whenever desired the probe can be disconnected from the tester valve in response to an appropriately timed reciprocable motion of the probe.

Abstract: Apparatus for retaining axial mandrel movement relative to a cylindrical housing. A cylindrical housing has an open longitudinal passageway therethrough and a circulation port disposed through a wall thereof. A valve mandrel is slidably received in the housing and is moveable between a position in which fluid may be circulated only between the passageway and the exterior of the housing, a position in which fluid may be circulated only between the exterior of the housing and the passageway and a position in which fluid may not be circulated in either direction. An annular piston is operatively connected to the valve mandrel and has a first side exposed to the pressure exterior of the housing and a second side exposure to the pressure interior of the housing to permit movement of the valve mandrel to its various positions by application of pressure to the interior and exterior of the housing.

Abstract: A method of well testing, including treating, whereby a testing string including a tool bore closure valve is run into the well bore with the valve in an open mode, the string may be automatically filled, a packer may be pressure tested without cycling the tool bore closure valve, and fluids may be spotted into the testing string, displacing wellbore fluids from the bottom of the testing string, prior to running the test.