Abstract: A system and method for evaluating a wellbore involves drawing fluid from a surrounding formation into an isolated portion of the wellbore, collecting the fluid in the isolated portion, and directing the sampled fluid to surge tanks on surface through a string of coiled tubing. The system and method includes measuring fluid properties, such as density and viscosity; and observing fluid flow characteristics, such as the fluid pressure, the fluid flowrate, and changes in the fluid flowrate. Based on the measured fluid properties and observed characteristics a determination is made if the wellbore is a candidate for a drill stem test.

Abstract: A gas control valve has a valve housing, a gas flowpath, a piston, a valve seat, a valve body, an actuating chamber, and a stack of Belleville washers. The valve housing has a gas inlet, a gas outlet, and a control fluid inlet. The gas flowpath runs from the gas inlet to the gas outlet. The piston reciprocates away from and towards a normal position. The valve body is coupled to the piston and is adapted to selectively seat on the valve seat to open and shut the gas flowpath. The actuating chamber communicates with the control fluid inlet. The washer stack is under compression to bias the piston in the normal position. The piston is responsive to fluid pressure in the actuating chamber and the washer stack so that the valve may be selectively opened and closed by sequentially increasing and decreasing pressure in the actuating chamber.

Abstract: A technique facilitates controlled injection of a chemical injection fluid at a desired downhole location. A chemical injection valve is mounted along a well tubing and is disposed externally of an internal flow passage through the well tubing. The chemical injection valve is operated via hydraulic pressure which is applied to actuate the chemical injection valve between closed flow and open flow positions. The chemical injection valve controls flow of the chemical injection fluid to at least one injection port. The at least one injection port may be positioned to inject the chemical injection fluid into the internal flow passage of the well tubing.

Abstract: Pressure relief systems for gas lift valves and mandrels are provided. In an implementation, a gas lift barrier mandrel includes two gas lift valves in series fluid communication. When fluid becomes confined between the two gas lift valves, an expansion volume is provided in one of the gas lift valves for pressure relief of the confined fluid, beginning at a pressure threshold value. The pressure relief may be mediated by a pressure-activated device, a piston, a spring, or a bellows to regulate the expansion of confined pressure. In an implementation, one of the gas lift valves may include a pressure relief valve to vent confined pressure from the gas lift valve to the production tubing or casing annulus. A check valve may be added in series with the pressure relief valve within the gas lift valve to prevent backflow through the pressure relief valve.

Abstract: The present invention relates to a downhole inflow control system for controlling an inflow of fluid into a casing from outside the casing, such as from a reservoir or an intermediate casing. The downhole inflow control system comprises a casing having an axial extension and a wall having a wall thickness (t), an inflow control valve having a housing, an axial extension in an axial direction along the housing, and a spring element moving in relation to the housing, thereby controlling the inflow of fluid through the valve from an inlet of the housing to an outlet of the housing.

Abstract: An apparatus usable with a well includes a gas lift valve having a check valve arrangement located between an annulus and a passageway of a tubing. The check valve arrangement is adapted to selectively allow fluid flow from the check valve arrangement from an inlet side of the check valve arrangement to an outlet side of the check valve arrangement, and is biased to prevent a leakage flow through the check valve arrangement from the outlet side to the inlet side. The check valve arrangement is defined by a valve element movable into and out of engagement with a valve seat wherein one of the valve element and the valve seat has a first sealing structure engageable with a second sealing structure on the other of the valve element and the valve seat. At least one of the first and second sealing surfaces include at least one pair of sealing members.

Abstract: A gas lift valve that is usable with a subterranean well includes a housing, a valve stem and at least one bellows. The housing has a port that is in communication with a first fluid, and the valve stem is responsive to the first fluid to establish a predefined threshold to open the valve. The bellow(s) form a seal between the valve stem and the housing. The bellow(s) are subject to a force that is exerted by the first fluid; and a second fluid contained in the bellow(s) opposes the force that is exerted by the first fluid.

Abstract: A pressure-operated valve is disclosed including a choke positioned between one or more inlet ports to the valve and a flow port within the valve defined by a seat to which a valve element may be sealed to close the valve. The choke includes one or more orifices to provide a constricted flow path such that control fluid, entering the inlet port, experiences a pressure drop before reaching the flow port, whereby fluid pressure downstream of the flow port may effectively control the configuration of the seat-and-valve element combination. The choke, which is sealed within the valve to prevent fluid flow around the choke, may be positioned at the inlet port to receive fluid flow into the valve.

Abstract: Disclosed is a bellows control valve with means to pressurize the bellows chamber to very high pressure without creating a significant detrimental differential pressure across the bellows.

Abstract: A gas lift valve having an adjustable stop for limiting valve stem travel such that the bellows may be preset to assure full valve opening in operation. To preset the valve, the stop is set so that the maximum stem travel is greater than that desired in operation, and an excess operating pressure is applied. The bellows is thereby permanently partially retracted so as to prevent the bellows from limiting stem travel to a distance less than the desired travel when the valve is in operation. The adjustable stop is repositioned to establish the operating stem travel before the valve is placed in use.

Abstract: A gas lift valve for use in a continuous flow operation which has an externally biased bellows which is pressurized internally to open the valve. A noncompressible liquid surrounds the bellows and flows upwardly through a passage about the valve stem into a dome in the valve which is pressurized to a predetermined pressure to resist movement of the bellows and opening of the valve. Fluid passes through a series of labyrinth rings formed on the valve stem adjacent the passage into the dome to dampen valve movement. An O-ring seal on the valve stem below the passage into the dome engages and seals off the passage if excessive pressure expands the bellows to a predetermined point such that the bellows will be protected from rupture by the noncompressible liquid trapped about the bellows. A snubber ring of nonmetallic material is positioned about the lower end of the valve stem to limit lateral movement of the valve ball in the seat.

Abstract: A gas lift valve is characterized by a valve element biased to the first, closed, position within a valve housing by an extension spring biasing element. In the closed position the valve element interdicts communication between an annular region disposed externally to a production tubing string and the interior of the tubing string. A bellows arrangement may be provided and may have a fluid therewithin able to be pressurized to a predetermined pressure level to assist the spring biasing element in biasing the valve to the closed position. The extension spring element is disposed witin the valve housing above the bellows element. The valve element is itself physically disconnected from, but abutted against a bellows sub element which transmits the closing force to the valve element when the valve element is in the closed position.

Abstract: A casing pressured operated, variable orifice valve is employed as the operating valve in a single point injection well assembly with tubing pressure (fluid) operated unloading valves acting above the operating valve to provide a continuous flow system. The operating valve includes a throttling range which extends between optimum injection gas pressure levels based on the amount of injection gas pressure available at the well head to thereby increase the overall efficiency of the system. The variable orifice valve includes a pressure charged bellows and a coil spring in series to produce a linear resultant load rate which in turn cooperates with contoured closure surfaces in the valve to produce a linear relationship between orifice size and injection gas pressure. Gas is thus injected into the production column or tubing at a rate which is linearly related primarily to the casing pressure with the throttling range of the operating valve producing a broad response in the gas injection rate.