A system for dewatering a subsea gas pipeline includes a pig launcher at the pipeline's upper end, which may be at or near the sea surface, and a pig receiver at the pipeline's lower end, which may be at or near the sea floor. A multiphase pump unit is deployed at the pipeline lower end and is configured to provide sea water suction to aid in a pig train being forced downwards through pipeline. The multiphase pump is configured to handle some amount of gas leaking around the pig train. A choke system may allow sea water to enter the flowline, thereby lowering the gas volume fraction (GVF) and preventing the GVF from exceeding the ability of the multiphase pump. For deeper water applications, a second pump may be provided in series that may be a single pump if positioned downstream of the multiphase pump.

A tool for intervention on the wall of a fluid pipe, comprising a duct segment through which the fluid is intended to flow when the tool is in the pipe, and at least first and second modules for creating seals between the wall of the pipe and the duct segment, to isolate the fluid circulating in an outer part of a section of the pipe, between the first and second seal creation modules.

The tool includes motorized rollers for moving the tool in the pipe and a module for determining the location of the tool in the pipe.

A method of minimizing material mixing in a piping system during a transition between a first material and a second material includes providing a plurality of pipe pigs in a first pipe section with the plurality of pipe pigs being sufficient to substantially fill a cross-section of the first pipe section and to define a plug having a leading edge and a trailing edge such that the leading edge is in contact with a first material and the trailing edge is in contact with a second material. Each pipe pig has a nominal size that is smaller than an effective diameter of the first pipe section. The plug is moved through the piping system by moving the second material. Advantageously, mixing of the first material and the second material is inhibited by the plug.

A method of minimizing material mixing in a piping system during a transition between a first material and a second material includes providing a plurality of pipe pigs in a first pipe section with the plurality of pipe pigs being sufficient to substantially fill a cross-section of the first pipe section and to define a plug having a leading edge and a trailing edge such that the leading edge is in contact with a first material and the trailing edge is in contact with a second material. Each pipe pig has a nominal size that is smaller than an effective diameter of the first pipe section. The plug is moved through the piping system by moving the second material. Advantageously, mixing of the first material and the second material is inhibited by the plug.

Techniques for implementing and/or operating a system that includes a pipe segment, in which the pipe segment includes tubing that defines a pipe bore and a fluid conduit within an annulus of the tubing, a bore device to be moved through the pipe bore of the pipe segment, in which the bore device includes an internal sensor that determines sensor data indicative of an electrical parameter that the bore device encounters while disposed in the pipe bore of the pipe segment and fluid blocking material implemented around the internal sensor, and a control sub-system communicatively coupled to the bore device. The control sub-system determines whether static charge is expected to be present in the pipe bore of the pipe segment based at least in part on the sensor data determined by the internal sensor of the bore device.

Techniques for implementing and/or operating a system that includes a pipe segment, in which the pipe segment includes tubing that defines a pipe bore and a fluid conduit within an annulus of the tubing, a bore device to be moved through the pipe bore of the pipe segment, in which the bore device includes an internal sensor that determines sensor data indicative of an electrical parameter that the bore device encounters while disposed in the pipe bore of the pipe segment and fluid blocking material implemented around the internal sensor, and a control sub-system communicatively coupled to the bore device. The control sub-system determines whether static charge is expected to be present in the pipe bore of the pipe segment based at least in part on the sensor data determined by the internal sensor of the bore device.

A method is provided for the autonomous assessment of pipelines. The apparatus combines one or more conventional modes of pipeline assessment in a unique untethered and unconstrained pipeline assessment device that is deployed at an upstream sewer access point and then propelled through multiple pipeline segments by the flow of liquid in the pipeline, thus allowing for the assessment of several pipeline segments much cheaper, faster, safer and less disruptive to the community than the current assessment methods.

A method is provided for the autonomous assessment of pipelines. The apparatus combines one or more conventional modes of pipeline assessment in a unique untethered and unconstrained pipeline assessment device that is deployed at an upstream sewer access point and then propelled through multiple pipeline segments by the flow of liquid in the pipeline, thus allowing for the assessment of several pipeline segments much cheaper, faster, safer and less disruptive to the community than the current assessment methods.

A method for controlling the velocity of a pipeline pig, the method including, introducing a pressurized gas into a section of pipeline to be treated and maintaining the velocity of a smart pipeline pig at a predetermined velocity by regulating the pressurized gas to a predetermined volume. A method for controlling the velocity of a pipeline pig, the method including fluidically connecting a first skid to a first end of a section of pipeline to be treated, fluidically connecting a second skid to a second end of the section of pipeline to be treated, introducing a pressurized gas into the section of pipeline to be treated via the first skid, launching a smart pipeline pig into the section of pipeline to be treated, and maintaining the velocity of the smart pipeline pig at a predetermined velocity by regulating the pressurized gas to a predetermined volume.

A method for controlling the velocity of a pipeline pig, the method including, introducing a pressurized gas into a section of pipeline to be treated and maintaining the velocity of a smart pipeline pig at a predetermined velocity by regulating the pressurized gas to a predetermined volume. A method for controlling the velocity of a pipeline pig, the method including fluidically connecting a first skid to a first end of a section of pipeline to be treated, fluidically connecting a second skid to a second end of the section of pipeline to be treated, introducing a pressurized gas into the section of pipeline to be treated via the first skid, launching a smart pipeline pig into the section of pipeline to be treated, and maintaining the velocity of the smart pipeline pig at a predetermined velocity by regulating the pressurized gas to a predetermined volume.