Abstract: A method for performing downhole gas lift operations includes coupling a gas lift valve to a tubing, wherein the gas lift valve includes an actuator, a flow control device disposed in the actuator, and a closure member that is initially in an open position; injecting a gas downhole and exterior to the tubing; urging the gas to enter the tubing via the gas lift valve; and creating a sufficient pressure differential across the gas lift valve to move the actuator, thereby causing the closure member to close the gas lift valve.

Abstract: A valve apparatus capable of withstanding high pressures and techniques for using this apparatus in various suitable applications are provided. The valve apparatus typically includes both an upper bellows comprising a standard, convoluted bellows and a lower bellows comprising an edge-welded bellows. The valve apparatus may also include a floating, constant volume fluid chamber that travels with the lower edge-welded bellows as the lower bellows compresses and expands in an effort to protect the lower bellows from very high internal volume fluid pressure.

Abstract: A gas lift apparatus has a gas lift valve that disposes in a mandrel. A housing of the valve has a chamber, and a seat disposes between the inlet and outlet. A piston movably disposed in the housing has one end exposed to the chamber. A distal end can selectively seal with the seat to close the valve. A first edge-welded bellows disposed on the piston separates the inlet and chamber pressures and can fully compress to a stacked height when the distal end of the piston seals with the seat. A dynamic seal can be achieved at closing by using a captive sliding seal between the piston's distal end and the seat. A second edge-welded bellows can also be disposed on the piston, and the two bellows can operate in tandem. Oil filing the interiors and the passage can move from one bellows to the other to transfer the pressure differential between the inlet and the chamber pressures. The second bellows fully compresses to a stacked height and stops opening of the valve.

Abstract: An apparatus for the manufacture of chemical vapor deposited domes. The apparatus has a vapor deposition chamber with a plurality of sides, a base and a top where the base has a reactant port for receiving a flow of chemical reactants. A male mandrel is joined to one of a plurality of sides of the deposition chamber such that the flow of chemical reactants in the vapor deposition chamber does not impinge on the mandrel.

Abstract: Embodiments include providing a gas lift system comprising production tubing disposed within a wellbore, the production tubing capable of allowing fluid flow in a first direction from outside the production tubing through a wall of the production tubing to inside the production tubing to introduce a gas into the bore of the production tubing, while preventing fluid flow in a second direction from inside the production tubing through the wall of the production tubing to outside the production tubing. In one aspect, fluid flow in the second direction is prevented by operation of at least two valve members disposed within a side pocket of a side pocket mandrel in the production tubing. At least one of the valve members is capable of preventing fluid flow in the second direction even when the other valve member is removed from the wellbore or is at least partially inoperative.

Abstract: Embodiments include providing a gas lift system comprising production tubing disposed within a wellbore, the production tubing capable of allowing fluid flow in a first direction from outside the production tubing through a wall of the production tubing to inside the production tubing to introduce a gas into the bore of the production tubing, while preventing fluid flow in a second direction from inside the production tubing through the wall of the production tubing to outside the production tubing. In one aspect, fluid flow in the second direction is prevented by operation of at least two valve members disposed within a side pocket of a side pocket mandrel in the production tubing. At least one of the valve members is capable of preventing fluid flow in the second direction even when the other valve member is removed from the wellbore or is at least partially inoperative.

Abstract: Near net shape free standing articles can be produced by chemical vapor deposition techniques when a suitable substrate is suspended in a chemical vapor deposition zone according to the disclosed technique. By suspending such substrates from linear suspension supports such as ropes, cables and wires, multiple near net shape articles can be produced with substantial manufacturing cost savings over previously employed techniques.

Abstract: An apparatus and method for preparing high aspect ratio domes employed to enhance aerodynamic performance in missiles and aircraft. The apparatus and method of the present invention also provide transmissive domes for infrared sensors used for navigation, targeting and guidance systems. The apparatus is employed in chemical vapor deposition furnaces for chemical deposition of materials on mandrels to form domes. The mandrels of the apparatus are arranged in the deposition chamber such that the flow of gaseous reactants does not impinge on the mandrels. The reactants diffuse onto the mandrels to form domes with high aspect ratios.

Abstract: An apparatus for the manufacture of chemical vapor deposited domes. The apparatus has a vapor deposition chamber with a plurality of sides, a base and a top where the base has a reactant port for receiving a flow of chemical reactants. A male mandrel is joined to one of a plurality of sides of the deposition chamber such that the flow of chemical reactants in the vapor deposition chamber does not impinge on the mandrel.

Abstract: Near net shape free standing articles can be produced by chemical vapor deposition techniques when a suitable substrate is suspended in a chemical vapor deposition zone according to the disclosed technique. By suspending such substrates from linear suspension supports such as ropes, cables and wires, multiple near net shape articles can be produced with substantial manufacturing cost savings over previously employed techniques.

Abstract: Near net shape free standing articles can be produced by chemical vapor deposition techniques when a suitable substrate is suspended in a chemical vapor deposition zone according to the disclosed technique. By suspending such substrates from linear suspension supports such as ropes, cables and wires, multiple near net shape articles can be produced with substantial manufacturing cost savings over previously employed techniques.

Abstract: An improved chemical vapor deposition (CVD) process which is capable of providing low-scatter water-clear zinc sulfide bulk material is described. The improved method also minimizes bowing, or induced curvature, in the product bulk material. The product zinc sulfide material can be processed into thicker windows and optical devices than was possible with the articles produced by the previous CVD process. The improved process provides for a controlled gradual initial ramping up of the deposition rate and a controlled initial ramping down of the substrate temperature.