A downhole tool has a tubular body defining an outer wall. A port is defined in the outer wall and a plug is received in the port. The plug is detachably connected to the outer wall and expellable into an annulus between the tubular body and a wellbore in which the downhole tool is placed upon the application of pressure in an interior of the tubular body.

A method of fracturing a rock formation includes cementing a production pipe to a wellbore within the rock formation, wherein a seat is attached to an inner surface of the production pipe. The method further includes forming access ports along a first section of the wellbore that fluidly connect the production pipe to the wellbore, delivering treatment fluid from the production pipe to the wellbore through the access ports, flowing formation fluid from the rock formation to the production pipe through the access ports, and closing an opening in the seat to isolate the first section of the wellbore from a second section of the wellbore located above the first section.

The present disclosure includes a plug for cementing a wellbore. The plug may include a cylinder. The cylinder may include at least one body including a non-conductive material with conductive filaments dispersed within the non-conductive material. The present disclosure also includes float equipment for cementing a wellbore. The float equipment may include a casing segment including an inner surface, drillable material affixed to the inner surface of the casing segment, and a check valve attached to the drillable material. The drillable material may include a non-conductive material and conductive filaments dispersed within the non-conductive material.

Provided in one aspect is a new tool and methodology to work, in a single-trip system, and create conduits through the casing or tubing to access the annuli, circulate out the annuli contents, accurately deliver the cement required to create the subsequent barrier. The tool and system provided by this aspect provide a cost effective way of plugging an oil and gas well in a single trip without the need to remove in-place production casing.

An improved method and apparatus for dropping a ball, plug or dart during oil and gas well operations (e.g., cementing operations) employs a specially configured tool body assembly having valving members (e.g., safety or kelly values) and valving members holding plugs, balls, or darts to be dropped. In one embodiment, the ball(s), dart(s) or plug(s) are contained in a sliding sleeve that shifts position responsive to valve rotation. An optional indicator indicates to a user or operator that a ball or plug has passed a selected one of the valving members. A transmitter (or transceiver) provides an ability to generate a wireless signal that is received by receivers (or transceivers) on the tool body assembly. Each receiver (or transceiver) controls an electrical actuator that engages a valving member or the indicator. Wireless signals can be used to open or close a valve or to reset a tripped indicator.

A wiper plug can be used in wellbore operations. The wiper plug can include a fishing neck located at a rear portion of the plug. The fishing neck can be a male or female fishing neck. A corresponding male or female fishing tool can be used to retrieve the wiper plug from a tubing string. The wiper plug can include a nose that can land on a landing tool or a female fishing neck of another wiper plug. The wiper plug can be introduced into the tubing string before or after a cement composition. The wiper plug can include a rupture disk that allows an operator at a wellhead to observe a pressure change to indicate the location of the wiper plug and fluid within the tubing string.

A wiper plug to activate an internal sleeve positioned within a landing collar, wherein the landing collar and the internal sleeve are integral components.

A subsurface release plug system includes a plug mandrel body and a plug. The plug mandrel body includes a bore, a flow port fluidly connected to the bore, and a sleeve adjustable from a first position to a second position. The sleeve prevents fluid flow through the flow port when in the first position and allows fluid flow through the flow port when in the second position. The plug is releasably connected to the plug mandrel body, wherein the plug is configured to be released from the plug mandrel body by fluid flowing through the flow port.

A system that can include a first sensor disposed within a tubular and configured to monitor a pressure within the tubular, a second sensor disposed within the tubular downstream of the first sensor and configured to monitor the pressure within the tubular, and a controller. The controller being configured to detect a launch of the cement plug when the first sensor detects a first pressure drop and when the second sensor detects a second pressure drop, where the second pressure drop occurs after the first pressure drop within a predetermined elapsed time range.

A system for tracking an object in oil and gas wellbore operations wherein a releasable object carrying a first signal system is released into tube system associated with a wellbore. The first signal system communicates with one or more second signal systems positioned along the travel path of the object; along the surface of the formation; and/or throughout the wellbore. First signal system and the second signal system may communicate by RF signals. First signal system and any second signal systems positioned on the surface communicate by through-the-earth or very low frequency signals. A global positioning system may be utilized in conjunction with any second signal systems on the surface to identify the absolute location of the object in the underground wellbore. The first signal system carried by the object may be a piezoelectric system disposed to transmit a signal when the object experiences a predetermined pressure.