A plug system includes a lower plug, an upper plug, and a sleeve configured to be positioned at least partially within the lower plug, the upper plug, or both. The sleeve defines one or more channels in an outer surface thereof. The sleeve is configured to shift axially from a first position into a second position with respect to the lower plug. In the first position, fluid is prevented from flowing through the one or more channels. In the second position, the fluid is permitted to flow through the lower plug via the one or more channels.

A system detects an acoustic-wave-producing downhole event associated with a pipe at an uphole location in the presence of surface noise. The system comprises: a first plurality of acoustic sensors located a first axial position along the pipe and oriented symmetrically about the pipe axis; and a second plurality of acoustic sensors located a second axial position along the pipe and oriented symmetrically about the pipe axis, the second axial position spaced apart from the first axial position. A processor is connected to receive the signals from the first and second pluralities of sensors and configured to process the sensor signals to thereby produce an output signal. The processor is configured to adjust the digital processing, based on the sensor signals, to minimize a contribution of the surface noise to the output signal.

A spoolable array of sensors may be deployed within a wellbore and external a tubular string for measuring properties of a fluid in the central flow passage of the tubular string. A flow port may be made in the tubular string passing from the central flow passage to the external surface. Sensors of the spoolable array of sensors may be covered with a shroud and placed proximate the flow port, or such sensors may be isolated in a zone with packers along with the flow port. The spoolable array of sensors may additionally obtain pressure data to calculate a flow rate from a production zone. The spoolable array of sensors may also be employed in a non-flowing wellbore for monitoring nearby wellbores.

A spoolable array of sensors may be deployed within a wellbore and external a tubular string for measuring properties of a fluid in the central flow passage of the tubular string. A flow port may be made in the tubular string passing from the central flow passage to the external surface. Sensors of the spoolable array of sensors may be covered with a shroud and placed proximate the flow port, or such sensors may be isolated in a zone with packers along with the flow port. The spoolable array of sensors may additionally obtain pressure data to calculate a flow rate from a production zone. The spoolable array of sensors may also be employed in a non-flowing wellbore for monitoring nearby wellbores.

Liner hangers and methods of use. An example method includes positioning a liner hanger in a wellbore; the liner hanger comprising: two sealing elements disposed on the exterior of the liner hanger and having a void space therebetween, and a pressure reducing metal element disposed between the two sealing elements. The method further includes trapping a wellbore fluid in the void space; wherein the wellbore fluid thermally expands in the void space creating an annular pressure in the void space; and reducing the annular pressure by materially altering the pressure reducing metal element.

A downhole valve is described. The downhole valve has a pilot valve section and a tool section. The pilot valve section has a first tube. The tool section has a second tube slidably coupled to the first tube of the pilot valve section so as to provide fluid communication between the pilot valve section and the tool section. The tool section can be in the form of a signal valve section of a mud pulse telemetry valve, a reamer, a vertical steerable tool, a rotary steerable tool, a by-pass valve, a packer, a whipstock, or stabilizer.

A buckle prevention ring assembly for use within a conduit, such as casing, having at least one buckle prevention ring may be provided. The buckle prevention ring may be bonded and may provide a fluid and gas tight seal to prevent fluid and gas from leaking out of the casing in a downhole environment.

A downhole tool for controlling the flow of a fluid in a wellbore includes a component that comprises: a cementitious material; an aggregate; and a ductility modifying agent comprising one or more of the following: an ionomer; a functionalized filler; the functionalized filler comprising one or more of the following: functionalized carbon; functionalized clay; functionalized silica; functionalized alumina; functionalized zirconia; functionalized titanium dioxide; functionalized silsesquioxane; functionalized halloysite; or functionalized boron nitride; a metallic fiber; or a polymeric fiber.

A downhole tool for controlling the flow of a fluid in a wellbore includes a component that comprises: a cementitious material; an aggregate; and a ductility modifying agent comprising one or more of the following: an ionomer; a functionalized filler; the functionalized filler comprising one or more of the following: functionalized carbon; functionalized clay; functionalized silica; functionalized alumina; functionalized zirconia; functionalized titanium dioxide; functionalized silsesquioxane; functionalized halloysite; or functionalized boron nitride; a metallic fiber; or a polymeric fiber.

A micro frac plug used to seal individual perforations formed in a casing installed within a subterranean wellbore. The plug comprises an insert element and a deformable sleeve. The insert element is received and retained within a medial section of the sleeve. The plug is sized to be lodged in or seated on a single perforation. The plug blocks fluid from flowing through the perforation.