Venturi controlled unloading valve for gas lift system

An unloading valve for use in evacuating fluids from a wellbore annulus, the unloading valve comprising:

• a valve body;
• an intake to the valve body;
• a discharge from the valve body;
• and
• an induced pressure differential valve control system configured to automatically close the intake to the valve body in response to a change in the density of fluids passing through the unloading valve, wherein the induced pressure differential valve control system comprises:
• a flow sleeve that comprises:
• an inlet adjacent to the intake;
• an outlet adjacent the discharge;
• and
• a flow constriction in the flow sleeve that produces a pressure differential (ΔP) as the fluids pass through the flow sleeve;
• a valve element configured to move from an open position to a closed position blocking the inlet;
• a draw tube that communicates the pressure differential (ΔP) to the valve element;
• a biasing spring attached to the first end of the valve element and configured to urge the valve element into the closed position against a force resulting from the pressure differential (ΔP);
• and
• a pin that secures the valve element in an initial open position.

An unloading valve for use in evacuating fluids from a wellbore annulus, the unloading valve comprising:

• a valve body;
• an intake to the valve body;
• a discharge from the valve body;
• and
• an induced pressure differential valve control system configured to automatically close the intake to the valve body in response to a change in the density of fluids passing through the unloading valve, wherein the induced pressure differential valve control system comprises:
• a flow sleeve;
• a valve element configured for linearly reciprocating movement within the flow sleeve between an open position and a closed position, wherein the valve element is substantially cylindrical with first and second ends and wherein the valve element comprises a bypass channel;
• a flow constriction in the flow sleeve that produces a pressure differential (AP) as the fluids pass through the flow sleeve;
• a biasing spring attached to the first end of the valve element;
• and
• a draw tube that communicates the pressure differential (AP) to the valve element.

An unloading valve for use in evacuating fluids from a wellbore annulus, the unloading valve comprising:

• a valve body;
• an intake to the valve body;
• a discharge from the valve body;
• and
• an induced pressure differential valve control system configured to automatically close the intake to the valve body in response to a change in the density of fluids passing through the unloading valve, wherein the induced pressure differential valve control system comprises:
• a flow sleeve that comprises:
• an inlet adjacent to the intake;
• an outlet adjacent the discharge;
• and
• a flow constriction in the flow sleeve that produces a pressure differential (ΔP) as the fluids pass through the flow sleeve;
• a valve element configured to move from an open position to a closed position blocking the inlet, wherein the valve element comprises a bypass channel;
• a draw tube that communicates the pressure differential (ΔP) to the valve element;
• a biasing spring attached to the first end of the valve element and configured to urge the valve element into the closed position against a force resulting from the pressure differential (ΔP).