A plunger lift system includes a bumper assembly to reduce the impact of the plunger at the bottom of the well and in some circumstances to reconfigure the plunger for the plunger's next ascent. The bumper assembly has a spring, a mandrel, an impact head, and a flow cage. The impact head and mandrel are constructed from a single piece of material thereby removing a joint between the impact head and mandrel. The unitary impact head/mandrel is connected to the flow cage using a first cooperating shoulder at the lower end of the unitary impact head/mandrel and a second cooperating shoulder within the flow cage. The first cooperating shoulder and the second cooperating shoulder are held in place with respect to each other by a force provided by the spring.

A bypass plunger includes a unibody, or one-piece hollow body and valve cage, retains a dart valve within the valve cage portion using a threaded retaining nut secured by crimple detents, and includes sealable flow parts. A series of helical grooves surround the central portion of the outer surface of the hollow body of the plunger to control spin during descent. A canted-coil-spring disposed within the retaining nut functions as a clutch. The valve cage includes ports that may be configured to control flow through the plunger during descent. Other embodiments include clutch assemblies using canted-coil springs with split bobbins, and surfaced valve stems surfaced.

A bypass plunger includes a unibody, or one-piece hollow body and valve cage, retains a dart valve within the valve cage portion using a threaded retaining nut secured by crimple detents, and includes sealable flow parts. A series of helical grooves surround the central portion of the outer surface of the hollow body of the plunger to control spin during descent. A canted-coil-spring disposed within the retaining nut functions as a clutch. The valve cage includes ports that may be configured to control flow through the plunger during descent. Other embodiments include clutch assemblies using canted-coil springs with split bobbins, and surfaced valve stems surfaced.

A plunger includes a sleeve having a passage therethrough and a valve member in the passage. When the plunger falls in a production string of a hydrocarbon well, the valve member is open and allows gas flow through the plunger. When the plunger contacts a liquid slug in the production string, the valve closes so that pressure from below reverses movement of the plunger so it pushes liquid above the plunger toward the earth's surface and ultimately to a well head where liquid and gas are separated.

A plunger includes a sleeve having a passage therethrough and a valve member in the passage. When the plunger falls in a production string of a hydrocarbon well, the valve member is open and allows gas flow through the plunger. When the plunger contacts a liquid slug in the production string, the valve closes so that pressure from below reverses movement of the plunger so it pushes liquid above the plunger toward the earth's surface and ultimately to a well head where liquid and gas are separated.

Described herein are embodiments of systems and apparatuses that include a dart and/or a clutch for a dart plunger. In an exemplary embodiment, the clutch consists of a one-piece unit having a length, an outside diameter, and an inside diameter where at least a portion of the inside diameter is sized to create a frictional interface with a dart. The clutch may also include a gap, a slot, and/or a spiral cut. The dart may include a shaft having opposite ends and a shaft diameter that varies between the opposite ends.

A plunger lift system, as well as a method for monitoring plunger parameters within a wellbore using such a plunger lift system, are provided. The plunger lift system includes a lubricator attached to a wellhead at the surface and a plunger dimensioned to travel through the production tubing upon being released from the lubricator. The plunger lift system also includes magnetic sensor systems installed along the production tubing, where each magnetic sensor system includes a magnetic sensor for detecting the passage of the plunger as it travels through the production tubing, as well a communication device for transmitting communication signals between the magnetic sensor systems and a computing system located at the surface, where the computing system includes a processor and a non-transitory, computer-readable storage medium including computer-executable instructions that direct the processor to dynamically determine the plunger position and/or velocity based on the received communication signals.

Provided herein, is magnetic catch assembly that may be utilized with and/or incorporated into lubricator of a wellhead. The magnetic catch assembly permits maintaining a plunger within the lubricator without requiring any moving mechanical components.

Provided herein, is magnetic catch assembly that may be utilized with and/or incorporated into lubricator of a wellhead. The magnetic catch assembly permits maintaining a plunger within the lubricator without requiring any moving mechanical components.

A multistage plunger lift system includes an upper production tubing segment positioned in a wellbore uphole of a lower production tubing segment, with the upper segment having a greater diameter than the lower segment. A lower travelling plunger and an upper traveling plunger are sized and configured to fit and travel within the lower segment and the upper segment, respectively. A plunger lift tool is positioned in the upper segment between the upper plunger and the lower plunger, and includes within its main body a fluid passageway with a one-way valve. A plunger receptacle sleeve at the bottom end of the lift tool receives the lower plunger and includes one or more vents configured to allow fluids to flow around the lower plunger when the lower plunger is received within the plunger receptacle sleeve.