Abstract: A method for injection of a lift gas into a wellbore production string comprises determining production pressure within the production string, and autonomously controlling a variable orifice gas lift valve in accordance with the determined production pressure, wherein the variable orifice gas lift valve controls the injection flow rate of the lift gas into the production string. A valve comprises a housing defining an inlet, an outlet and a flow path therebetween, and a valve member linearly moveable within the housing between first and second positions to vary flow along the flow path, wherein the valve member is prevented from rotation relative to the housing during linear movement between the first and second positions. The valve further includes a rotary drive and a transmission arrangement interposed between the rotary drive and the valve member for converting rotation of the rotary drive to linear movement of the valve member.

Abstract: A method for injection of a lift gas into a wellbore production string comprises determining production pressure within the production string, and autonomously controlling a variable orifice gas lift valve in accordance with the determined production pressure, wherein the variable orifice gas lift valve controls the injection flow rate of the lift gas into the production string. A valve comprises a housing defining an inlet, an outlet and a flow path therebetween, and a valve member linearly moveable within the housing between first and second positions to vary flow along the flow path, wherein the valve member is prevented from rotation relative to the housing during linear movement between the first and second positions. The valve further includes a rotary drive and a transmission arrangement interposed between the rotary drive and the valve member for converting rotation of the rotary drive to linear movement of the valve member.

Abstract: A side-pocket mandrel is used for a gas lift system. The mandrel has two external ports, which can use external check valves when deployed downhole. Before installing the mandrel, operators preferably pressure test the interface of a gas lift valve in the pocket of the mandrel. Internal pressure testing is performed. The mandrel, however, is suited for external-pressure testing, which is impractical for other types of side-pocket mandrels. In the external pressure test, a pressure test line is coupled to the inlet port on the mandrel, which is already threaded in a reinforced area of the mandrel to receive a check valve. The other inlet port is closed off with a plug or with a check valve. When external pressure is applied with the test line, operators can determine if the gas lift valve is properly seated (i.e., whether the latch is properly engaged in the pocket). Operators can also determine if the seals between the gas lift valve and the pocket are capable of holding external pressure.

Abstract: A method of removing produced fluid from a well producing both gas and liquid comprises utilising produced gas flowing from a formation to power a produced liquid pump. The produced liquid from the pump and the produced gas are carried towards surface in separate fluid streams, and may be commingled closer to surface.

Abstract: A method of removing produced fluid from a well producing both gas and liquid comprises utilising produced gas flowing from a formation to power a produced liquid pump. The produced liquid from the pump and the produced gas are carried towards surface in separate fluid streams, and may be commingled closer to surface.