Abstract: An auto-shut-in valve in a chemical injection valve is described for operation at a downhole location in a wellbore. The chemical injection valve includes a closure member that is maintained in an open position by fluid pressure in a chemical supply line such that diminishment of the fluid pressure in the chemical supply line automatically causes the closure member to move to a closed position. A first mating surface on the closure member is exposed to the fluid pressure in the chemical supply line when the closure member is in the open position, and defines a portion of an equivalent differential surface to which the fluid pressure is exposed to maintain the closure member in the open position. The first mating surface is isolated from the fluid pressure in the chemical supply line when the closure member is in the closed position.

Abstract: An auto-shut-in valve in a chemical injection valve is described for operation at a downhole location in a wellbore. The chemical injection valve includes a closure member that is maintained in an open position by fluid pressure in a chemical supply line such that diminishment of the fluid pressure in the chemical supply line automatically causes the closure member to move to a closed position. A first mating surface on the closure member is exposed to the fluid pressure in the chemical supply line when the closure member is in the open position, and defines a portion of an equivalent differential surface to which the fluid pressure is exposed to maintain the closure member in the open position. The first mating surface is isolated from the fluid pressure in the chemical supply line when the closure member is in the closed position.

Abstract: A downhole chemical injection system for positioning in a well. The system includes a generally tubular mandrel having an axially extending internal passageway and an exterior. The mandrel includes an injection port in fluid communication with the internal passageway or the exterior of the mandrel. A chemical injection line is coupled to the mandrel and is operable to transport a treatment fluid from a surface installation to the mandrel. A check valve is supported by the mandrel and is in downstream fluid communication with the chemical injection line. A density barrier is fluidically positioned between the check valve and the injection port. The density barrier has an axial loop and a circumferential loop relative to the mandrel forming an omnidirectional low density fluid trap, thereby preventing migration of production fluid from the injection port to check valve regardless of the directional orientation of the well.

Abstract: A downhole chemical injection system for positioning in a well. The system includes a generally tubular mandrel having an axially extending internal passageway and an exterior. The mandrel includes an injection port in fluid communication with the internal passageway or the exterior of the mandrel. A chemical injection line is coupled to the mandrel and is operable to transport a treatment fluid from a surface installation to the mandrel. A check valve is supported by the mandrel and is in downstream fluid communication with the chemical injection line. A density barrier is fluidically positioned between the check valve and the injection port. The density barrier has an axial loop and a circumferential loop relative to the mandrel forming an omnidirectional low density fluid trap, thereby preventing migration of production fluid from the injection port to check valve regardless of the directional orientation of the well.