A directional drilling-exploring-monitoring integrated method for guaranteeing safety of an underwater shield tunnel includes: drilling a small-diameter borehole below a water area, and establishing an initial geological model; reaming the small-diameter borehole into a large-diameter borehole, placing a parallel electrical method (PEM) power cable and a monitoring optical fiber cable into the large-diameter borehole, acquiring zero field data, primary field data and secondary field data through carbon rod measurement electrodes before tunnel excavation, and processing the data with an existing inversion method to form an inversion image, thereby obtaining a refined geological model of a stratum; starting the tunnel excavation, and respectively acquiring a disturbance condition of rock and soil and a sedimentation and deformation condition of rock and soil around the tunnel during the excavation, thereby implementing safety excavation of the tunnel; and continuously monitoring the tunnel and the surrounding rock and soil in later use of the tunnel.

A system and method of reverse stage cementing in which flow into a casing string from an annulus between the casing string and wellbore walls is pressure dependent; the flow is blocked after stage completion. The flow enters the casing string through a cementing sub integrally formed in the casing string. A flapper valve is in a sidewall of the cementing sub that opens when pressure in the annulus reaches a threshold value, and remains open until the annulus pressure falls below the threshold value. Flapper valve actuation is controlled by a hinge spring that is calibrated to open and close the flapper valve based on the annulus pressure. Also in the cementing sub is a sleeve that is positioned behind the flapper valve after the reverse stage cementing is completed. Sleeve actuation is timed to allow adequate time for the flapper valve to return to the closed position.

A self-destructible frac ball is described herein. The self-destructible frac ball is configured to seal a hydraulic flow path through a fluid conduit of a frac plug when engaged on a ball seat of the frac plug. The self-destructible frac ball includes an activation mechanism configured to activate a destructive medium in response to the satisfaction of at least one predetermined condition. The self-destructible frac ball also includes the destructive medium, which is configured to destroy the self-destructible frac ball and a corresponding destructible ball retainer when activated by the activation mechanism. The destruction of the self-destructible frac ball and the corresponding destructible ball retainer reestablishes the hydraulic flow path through the fluid conduit of the frac plug.

A self-destructible frac ball is described herein. The self-destructible frac ball is configured to seal a hydraulic flow path through a fluid conduit of a frac plug when engaged on a ball seat of the frac plug. The self-destructible frac ball includes an activation mechanism configured to activate a destructive medium in response to the satisfaction of at least one predetermined condition. The self-destructible frac ball also includes the destructive medium, which is configured to destroy the self-destructible frac ball and a corresponding destructible ball retainer when activated by the activation mechanism. The destruction of the self-destructible frac ball and the corresponding destructible ball retainer reestablishes the hydraulic flow path through the fluid conduit of the frac plug.

A method for sealing a side pocket mandrel and hydraulic tube includes moving a sealant dispenser into a pocket of the side pocket mandrel from within a well tubing. The sealant dispenser has an upper seal and a lower seal spaced apart therefrom; the seals are sealingly engaged with the pocket. A space between the upper seal and the lower seal is in fluid communication with at least one port in the pocket. A curable sealant is moved from the sealant dispenser into the pocket and into the tube. Either the sealant is allowed to cure or the sealant dispenser is unlatched from a running tool used to move the sealant dispenser into the pocket.

A frac plug with a flapper positioned within a shearable housing. More specifically, embodiments are directed towards an upper portion of the shearable housing that is configured to be separated from an insert responsive to flowing back through the frac plug.

A frac plug with a flapper positioned within a shearable housing. More specifically, embodiments are directed towards an upper portion of the shearable housing that is configured to be separated from an insert responsive to flowing back through the frac plug.

A system and method for a composite cement retainer. A composite cement retainer has various components. When these various components comprise composite where feasible, or a drillable metal, the retainer can be easily placed and quickly drilled if necessary.

A system and method for a composite cement retainer. A composite cement retainer has various components. When these various components comprise composite where feasible, or a drillable metal, the retainer can be easily placed and quickly drilled if necessary.

Provided is a slip ring for use with a sealing assembly, a sealing tool, and a method for sealing an annulus within a wellbore. The slip ring, in at least one aspect, includes a ring member having a first end, a second opposing end, a width (w), and a wall thickness (t). The slip ring, in this aspect, may additionally include a slot located entirely through the wall thickness (t) and extending between the first end and the second opposing end, the slot configured to allow the ring member to move between a radially reduced state and a radially enlarged state, and further wherein a first portion of the slot located at the first end and a second portion of the slot located at the second opposing end are radially offset from one another by at least 15-degrees.