A cementing head apparatus includes a plug-launching tool and a tubular plug receiver cage disposed within a bore of the launching tool, plus one or more paddles selectively movable within a bore of the receiver cage between a hold position in which the paddles at least partially occlude the receiver cage bore to hold a plug within a retained plug interval of the receiver cage bore, and a launch position in which the paddles are substantially retracted from the receiver cage bore to allow passage of the plug through the receiver cage bore and onward into a casing string to which the launching tool is mounted. Upper and lower fluid bypass ports may be provided through the wall of the receiver cage, above and below the retained plug interval, to allow fluid flow within the receiver cage bore to bypass the retained plug interval via the receiver annulus

A subsea coiled tubing drilling system and a subsea drilling device thereof are provided. The subsea drilling device includes an underwater derrick, a well head device and a dual-roller coiled tubing device, the dual-roller coiled tubing device includes an injection head, a roller for drilling and a roller for running casing, the injection head is arranged right above the well head device, the roller for drilling and the roller for running casing are distributed on two sides of the injection head; both the drilling coiled tubing and the casing running coiled tubing are capable of respectively penetrating through the injection head and the well head device in sequence. Drilling and casing running operations can be realized on the basis of not moving the underwater derrick or changing the self structure state of the underwater derrick, and operation steps can be simplified, and the work efficiency can be improved.

A subsea coiled tubing drilling system and a subsea drilling device thereof are provided. The subsea drilling device includes an underwater derrick, a well head device and a dual-roller coiled tubing device, the dual-roller coiled tubing device includes an injection head, a roller for drilling and a roller for running casing, the injection head is arranged right above the well head device, the roller for drilling and the roller for running casing are distributed on two sides of the injection head; both the drilling coiled tubing and the casing running coiled tubing are capable of respectively penetrating through the injection head and the well head device in sequence. Drilling and casing running operations can be realized on the basis of not moving the underwater derrick or changing the self structure state of the underwater derrick, and operation steps can be simplified, and the work efficiency can be improved.

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.

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.

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 valving member with curved and flat portions that alternatively direct fluid flow through a bore or opening in the valving member via an inner channel or around the periphery of the valving member in an outer channel. 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.

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 valving member with curved and flat portions that alternatively direct fluid flow through a bore or opening in the valving member via an inner channel or around the periphery of the valving member in an outer channel. 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 cementing head apparatus includes a plug-launching tool and a tubular plug receiver cage disposed within a bore of the launching tool, plus one or more paddles selectively movable within a bore of the receiver cage between a hold position in which the paddles at least partially occlude the receiver cage bore to hold a plug within a retained plug interval of the receiver cage bore, and a launch position in which the paddles are substantially retracted from the receiver cage bore to allow passage of the plug through the receiver cage bore and onward into a casing string to which the launching tool is mounted. Upper and lower fluid bypass ports may be provided through the wall of the receiver cage, above and below the retained plug interval, to allow fluid flow within the receiver cage bore to bypass the retained plug interval via the receiver annulus

A cementing head apparatus includes a plug-launching tool and a tubular plug receiver cage disposed within a bore of the launching tool, plus one or more paddles selectively movable within a bore of the receiver cage between a hold position in which the paddles at least partially occlude the receiver cage bore to hold a plug within a retained plug interval of the receiver cage bore, and a launch position in which the paddles are substantially retracted from the receiver cage bore to allow passage of the plug through the receiver cage bore and onward into a casing string to which the launching tool is mounted. Upper and lower fluid bypass ports may be provided through the wall of the receiver cage, above and below the retained plug interval, to allow fluid flow within the receiver cage bore to bypass the retained plug interval via the receiver annulus

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.