Systems and methods for initiating an emergency disconnect sequence (EDS) are provided. In an aspect, a disconnection system is provided and configured to initiate the EDS, and includes a controller including a processor and a memory operably coupled to the processor. The controller receives, from a set of motion reference units (MRU(s)) operably coupled to a flexible joint, position data generated by the set of motion references units and associated with the joint when the joint is operably coupled to and disposed between a drilling riser and a lower marine riser package (LMRP). The controller determines, based on the position data, an angular offset of the joint. The controller sends, to a subsea control pod disposed at or adjacent to the LMRP, a trigger signal in response to determining that the angular offset exceeds a predetermined threshold, such that the subsea control pod initiates the EDS.

Systems and methods for initiating an emergency disconnect sequence (EDS) are provided. In an aspect, a disconnection system is provided and configured to initiate the EDS, and includes a controller including a processor and a memory operably coupled to the processor. The controller receives, from a set of motion reference units (MRU(s)) operably coupled to a flexible joint, position data generated by the set of motion references units and associated with the joint when the joint is operably coupled to and disposed between a drilling riser and a lower marine riser package (LMRP). The controller determines, based on the position data, an angular offset of the joint. The controller sends, to a subsea control pod disposed at or adjacent to the LMRP, a trigger signal in response to determining that the angular offset exceeds a predetermined threshold, such that the subsea control pod initiates the EDS.

An application method of a device for accurately evaluating the vertical content distribution of an undersea hydrate reservoir includes the following steps: assembling the device into a whole and screwing it into an undersea well; activating natural gas hydrates to produce gaseous substances; opening a directional guide channel corresponding to a thermal excitation system in a working state in S2, so that gaseous natural gas hydrates generated in this horizon enter a screw-in long sleeve through the directional guide channel; collecting, by a gas collection system, the gaseous natural gas hydrates; analyzing and recording components and contents in a box by an optical ranging unit and a resistivity unit; repeating S4 and S5 till the end of one collection cycle; and performing data processing and analysis. In this way, accurate evaluation of the vertical content distribution of undersea hydrates is realized.

Systems, devices and methods enable generation and monitoring of support platform structural conditions in a manner that overcomes drawbacks associated with conventional approaches (e.g., load cells) for generating and monitoring similar operating condition information. In preferred embodiments, such systems, devices and methods utilize fiber optic strain gauges (i.e., fiber optic sensors) in place of (e.g., retrofit/data replacement) or in combination with conventional load cells. The fiber optic sensors are strategically placed at a plurality of locations on one or more support bodies of a support platform. In preferred embodiments, the fiber optic strain gauges are placed in positions within a hull and/or one or more pontoons of an offshore platform. Such positions are selected whereby resulting operating condition data generated by the fiber optic strain gauges suitably replaces data received by conventionally constructed and located load cells of an offshore platform (e.g., a TLP).

A system for preventing annular pressure buildup comprising: a wellbore; two or more annuli located within the wellbore; a piston assembly located adjacent to a wellhead of the wellbore; and a pipe system that connects the two or more annuli in parallel to the piston assembly, wherein when the amount of pressure in the pipe system exceeds a predetermined amount, then a piston of the piston assembly moves whereby the movement reduces the amount of pressure in the two or more annuli.

An in-situ and on-line acoustic measuring system for natural gas flux at the hydrocarbon seeps at a seafloor includes a seepage tent and a flow measuring channel. The flow measuring channel includes a lower bubble breaking channel, an ultrasonic transducer measuring channel and an upper bubble breaking channel. The lower bubble breaking channel communicates with the seepage tent provided with bubble breaking grids. Lower and upper bubble breaking devices, arranged in a bubble rising direction, are respectively mounted in the lower and upper bubble breaking channels. One side of the ultrasonic transducer measuring channel is fixedly connected with an acoustic wave demultiplexer, and the other side is fixedly connected with flat receiving transducers receiving transmitting acoustic waves generated by an acoustic wave branching unit. Acoustic wave probes, also used for receiving the transmitting acoustic waves generated by the acoustic wave demultiplexer, are arranged in the ultrasonic transducer measuring channel.

An in-situ and on-line acoustic measuring system for natural gas flux at the hydrocarbon seeps at a seafloor includes a seepage tent and a flow measuring channel. The flow measuring channel includes a lower bubble breaking channel, an ultrasonic transducer measuring channel and an upper bubble breaking channel. The lower bubble breaking channel communicates with the seepage tent provided with bubble breaking grids. Lower and upper bubble breaking devices, arranged in a bubble rising direction, are respectively mounted in the lower and upper bubble breaking channels. One side of the ultrasonic transducer measuring channel is fixedly connected with an acoustic wave demultiplexer, and the other side is fixedly connected with flat receiving transducers receiving transmitting acoustic waves generated by an acoustic wave branching unit. Acoustic wave probes, also used for receiving the transmitting acoustic waves generated by the acoustic wave demultiplexer, are arranged in the ultrasonic transducer measuring channel.

A christmas tree assembly for a subsea hydrocarbon extraction facility, the christmas tree assembly includes a fluid pipeline and a sensor assembly comprising a plurality of sensors configured to monitor a plurality of properties relating to hydrocarbon fluid flow through the fluid pipeline. The sensor assembly includes a differential pressure sensor that is disposed at one or more of across a choke, around a bend or restriction in the pipeline or a dedicated flow restrictor integrated within the pipeline, and a bulk density sensor that is disposed in one or more of a blind T, before or after a choke or in an upwards section of the flow pipeline.

A subsea umbilical termination assembly comprising: an umbilical termination head fixed to the end of a subsea umbilical; and an electrical and/or optical distribution unit comprising a base frame and several connectors mounted to the base frame, wherein each connector is electrically connected to an electrical cable of the subsea umbilical via the umbilical termination head or optically connected to an optical cable of the subsea umbilical via the umbilical termination head. The umbilical termination head is mounted in a space provided inside the base frame of the distribution unit.

A downhole communication system for communication between a first and second location in a subsea oil and/or gas well installation. The oil and/or gas well installation comprises out of hole metallic structure comprising a riser 3 running upwards away from the mudline ML, and downhole metallic structure 2 running down into the well. The communication system is arranged so that at least part of a signal path for communications between the first and second locations is provided by the downhole metallic structure 2 such that, in use, data to be communicated between the first and second locations is carried by electrical signals in the downhole metallic structure 2. The communication system further comprises a first noise cancellation arrangement arranged for sensing a noise signal generated in the out of hole metallic structure and arranged for applying a corresponding noise cancelling signal to the out of hole metallic structure or the downhole metallic structure to inhibit introduction of electrical noise into the downhole metallic structure 2 from the riser 3.