A valve for use in conjunction with operations in a subterranean well. The valve has an interior axially extending flow passage, a seat disposed adjacent the flow passage, a blocking member selectively displaceable relative to the seat between a first position in which the blocking member sealingly engages the seat to block fluid flow through the flow passage and a second position in which fluid flow through the flow passage is permitted, a first piston interconnected to the blocking member for selectively displacing the blocking member relative to the seat, and a first line in fluid communication with the first piston. Fluid pressure in the first line is capable of biasing the first piston to displace the blocking member to the second position. The valve further comprises a second piston interconnectable to the blocking member for selectively displacing the blocking member relative to the seat; and a first fluid passage capable of being in fluid communication with the second piston and the flow passage, fluid pressure in the first fluid passage being capable of biasing the second piston to displace the blocking member to the second position.

A well testing tool (50) which includes lateral circulation ports (296) and a ball valve (374), each operable between open and closed positions to configure the tool into different modes of operation, which include: a well test position in which the valve is open and the ports are closed; blank position in which the valve and ports are closed; and a circulating position in which the valve is closed and the ports are open. The tool can be switched between modes by manipulating pressure in the wellbore (4). An operating mandrel assembly (412) is provided, which is responsive to variations in annulus pressure, and moves between several mandrel positions to configure the tool into the different modes. An overrideable position controller (228,276) dictates the response of the operating mandrel assembly. The controller provides a default position sequence in which the mandrel assembly is maintained in primary mandrel positions. The controller is overrideable to permit selective movement of the operating mandrel assembly into alternative mandrel positions.

A ball valve which can be used to cut coiled tubing extending therethrough, includes a ball (154) rotatably disposed within a housing and adjacent to a seat (152). Control arms (156,158) prevent relative longitudinal movement between the ball (154) and seat (152). The ball defines a pair of slots (202,204) therein, each slot having a bearing surface. A pair of control pins (164,166) are disposed on opposite sides of the ball and rotatably disposed in corresponding control frames (160,162) disposed on opposite sides of the ball. Each control pin (164,166) has an end (208) with a bearing surface (206,212) thereon extending into a corresponding slot (202,204) in the ball so that flat contact is provided between the control pin and the ball. This greater area of contact between the pins (164,166) and the slots (202,204) allows a greater load to be transmitted to the ball to provide the shearing load necessary to shear relatively large diameters of coiled tubing which extend through the open valve. The valve is opened and closed by pressure actuation of a piston.

A well testing tool (50) which includes lateral circulation ports (296) and a ball valve (374), each operable between open and closed positions to configure the tool into different modes of operation, which include: a well test position in which the valve is open and the ports are closed; blank position in which the valve and ports are closed; and a circulating position in which the valve is closed and the ports are open. The tool can be switched between modes by manipulating pressure in the wellbore (4). An operating mandrel assembly (412) is provided, which is responsive to variations in annulus pressure, and moves between several mandrel positions to configure the tool into the different modes. An overrideable position controller (228,276) dictates the response of the operating mandrel assembly. The controller provides a default position sequence in which the mandrel assembly is maintained in primary mandrel positions. The controller is overrideable to permit selective movement of the operating mandrel assembly into alternative mandrel positions.

A well testing tool has a housing (32) having a central bore (21) and a port (40) through a wall in said housing; said housing further including a rupture port (46) in said wall sealed by a rupture disc (44); a member (70) slidably mounted in said housing (32) between a first position closing said port (40) and a second position opening said port, said member having an interior port (92) in a wall of said member which communicates with said central bore (21), said member (70) and housing (32) forming an annular cylinder (90,48) with said member having a piston member (74) extending into said cylinder; and said rupture port (40) communicating with said cylinder (48) on one side of said piston member (74) and said interior port (92) communicating with another side of said piston (74) whereby a pressure differential across said piston member causes said piston member to slide said member (70) from said first position to said second position.

A pressure test and bypass valve for use in well testing has a housing (60) defining a central opening (62) therein and a mandrel (126) slidably disposed in the central opening. A ball valve (102) allows fluid flow through the central opening (62) when in an open position and prevents fluid flow therethrough when in a closed position. A sleeve valve (150) allows communication between the central opening (62) and a well annulus when in an open position and prevents communication between the central opening (62) and the well annulus when in a closed position. The ball valve (102) and sleeve valve (150) are actuated substantially simultaneously in response to well annulus pressure. A rupture disc (186) is ruptured due to differential pressure thereacross. This allows well annulus pressure to act across a differential area on the mandrel (126) such that the mandrel is moved relative to the housing (60), thereby actuating the valves (102,150).

A control apparatus for a downhole tool comprises a sensor (84), eg. pressure sensor, for sensing a command signal; interpreting means (86), eg. a microprocessor, for interpreting the sensed signal; an electric motor (78) responsive to the interpreting means (86), and a battery (88) for supplying electric current to the interpreting means and to the electric motor. Command signals can be provided by well annulus pressure variations to operate the control apparatus.

An annulus pressure responsive downhole tool (50) includes a selectively actuable deactivating system (66) to render the tool unresponsive to annulus pressure changes. The tool includes a power piston (54), one side (56) of which is exposed to annulus pressure and the other side (58) of which is communicated with a reference pressure which, when it is different from the annulus pressure, results in a pressure differential across the power piston to cause it to move. Connected into the reference pressure side (58) is the deactivating system (66) which upon actuation ensures that the reference pressure is equal to the annulus pressure, thus preventing any pressure differential across the power piston (54).

An elongated valve means (10) is operable between a closed and opened position and is connected to a tubing string (14) for flowing fluid along an isolated flow path from a location downhole in a wellbore (11) to the surface. The valve means includes a main housing (41) within which a mandrel (38) is axially aligned. A packer (17) divides the borehole annulus into an upper and lower annular area. The valve device includes an annular power chamber (62) formed between the mandrel and the main body, and slidably receives a power piston (63) therewithin. The power piston is connected to a medial part of the mandrel. Metered flow from the upper borehole is indirectly effected on the piston face, thereby driving the piston uphole and carrying the mandrel therewith. The lower end of the mandrel has ports (75) formed through a sidewall thereof which are brought into registry with a complementary port (70) formed through the sidewall of the main housing. The housing port is in fluid communication with the lower borehole annulus. Detents (54) formed in the mandrel are engageable by a latch means (53) which positions the mandrel axially as the ports are brought into registry with one another. The latch means is retracted by a piston operated arm (51). Fluid pressure from the upper borehole annulus indirectly actuates the piston operated arm. The movement of the piston actuated arm and the power piston sequentially occur so that the latch means successively engages adjacent detents while successive ones of the mandrel ports are brought into registry with the port of the housing. Accordingly, the valve means is opened to admit fluid thereinto and up to the surface of the ground, whereupon the valve means is then moved to a first closed position, and thereafter again moved into the open position in response to hydrostatic pressure alternately being effected within the upper borehole annulus.

A multi-mode testing tool operable as a drill pipe tester, formation tester, nitrogen displacement valve or circulation valve, comprises a housing defining a longitudinal bore (370), and valve means (330) operable in at least a circulation valve mode and a displacement valve mode. An operating means (260) is provided to change the valve means between valve modes responsive to changes in pressure near the tool in the well bore, the operating means including a fluid filled chamber (210), a pressure responsive double-acting piston means (168,190,192), two longitudinally spaced piston stop means (127,146), and a ball and slot ratchet means (164,186).