Embodiments provide a method of controlling a flow of pipeline fluid through a pipeline pig that includes a bypass channel and at least one relief channel extending therethrough. The method includes (a) inserting the pipeline pig into a pipeline through which the pipeline fluid is flowing, (b) increasing a differential pressure established in the pipeline fluid between a trailing end and a leading end of the pipeline pig such that the differential pressure sequentially reaches a pre-selected minimum relief pressure, a pre-selected maximum relief pressure and a pre-selected minimum bypass pressure, (c) opening the at least one relief valve to permit the pipeline fluid to flow through the relief channel when the differential pressure reaches the pre-selected minimum relief pressure (d) closing the at least one relief valve to restrict the flow of pipeline fluid through the relief channel when the differential pressure reaches a pre-selected maximum relief pressure, and (e) opening a bypass valve to permit the pipeline fluid to flow through the bypass channel when the differential pressure reaches the pre-selected minimum bypass pressure.

Certain exemplary embodiments comprise a seal assembly, a mandrel, a front module, and/or a rear module. At least one of the front module and the rear module comprises a mount hub, a seal assembly, a chassis, and/or a mount plate. Various annular sealing assemblies can be mounted and dismounted to and from the mount hub. The mount hub can provide substantial central support for the sealing system. The chassis can be constructed to couple the mount hub to the seal element. The mount plate can be constructed to couple the module to the mandrel. The modular pipeline pig is substantially modular. Certain exemplary embodiments provide for relatively rapid mounting and dismounting of elements to and from the module assembly. In practice, such embodiments allow for quickly and easily configuring a pigging system for many different applications.

In one aspect, the present invention relates to a method for displacing fluid from a pipe. The method includes engaging a fluid-displacement system with the pipe. A displacement agent is pumped into the pipe via the fluid-displacement system. Fluid present within the pipe is displaced by the displacement agent. The pipe is manipulated in a desired manner.

Described herein are methods and system that use electromagnetic heating to heat pipelines, flowlines and the fluids therein. The heating is achieved by placing one or more permanent magnets in the wellbore and moving a metallic component and/or one or more permanent magnets relative to each other. This generates eddy currents in the metallic component or the pipeline wall, which heat the metallic component or pipeline wall and the fluids therein. The relative motion between the magnets and the metallic component is driven by the fluid pressure that drives the pig through the pipeline.

A projectile launching apparatus for cleaning the inner surface of a tube by forcing a projectile through the tube, comprising: a main body containing a breech chamber terminating in an exit port, wherein the breech chamber is provided with a loading port in a side thereof for radially loading a projectile into the breech chamber; a slide disposed on an exterior surface of the main body, the slide being axially movable between a first position wherein the loading port is exposed for loading of a projectile into the breech chamber and a second position wherein the loading port and the breech chamber are sealed; a gas gun operatively connected to the main body in pneumatic communication with the breech chamber; and an exit nozzle connected to the exit port and being connectable to a first end of the tube to be cleaned.

A self-powered pipeline pig includes a housing defining a trailing end, a leading end and a longitudinal axis. The plurality of internal flow channels extend longitudinally through the housing between the trailing end and the leading end. A power generation device is disposed in a first one of the plurality of internal flow channels. The power generation device generates electric power from a pipeline fluid flowing through the first flow channel during a pigging operation. A battery is disposed on the self-powered pipeline pig to provide electric power during the pigging operation to operate one or more components installed on the self-powered pipeline pig. The power generation device is electrically coupled to the battery to recharge the battery using the generated electric power.

A dart assembly for cleaning tubes including at least one annular disk having a first end, a second end, an outer perimeter and at least one longitudinal groove in the outer perimeter extending from the first end to the second end and at least one cutting wheel. The cutting wheel is positioned within the groove such that a portion of the cutting wheel extends into the groove and a portion extends beyond the outer perimeter of the annular disk. The dart assembly may also include at least one scraper disk and the annular disk and the scraper disk may be positioned at opposite ends of a shaft. Also, a method of cleaning a tube where a dart assembly is inserted into the inner diameter of the tube and forced through the tube using pressurized fluid. The dart assembly may have any or all of the features described above.

Systems and methods for cleaning an internal bore of a tubular member with a pipeline pig include a pipeline pig having a pig body with a fore end and an aft end opposite the fore end. A cup circumscribes the pig body, where an outer diameter lip of the cup engages a surface of the internal bore of the tubular member. A scraper assembly includes a scraper arm extending radially outward from the pig body and a spring biasing the scraper arm in a radially outward direction. A load cell is positioned to measure a movement of the scraper arm in a radially inward direction. A treatment trigger is actuated by a treatment signal from the load cell to deliver a treatment system to the internal bore of the tubular member, where the treatment signal is generated by the movement of the scraper arm in the radially inward direction.

A pipeline pig includes a plurality of relief channels and a bypass channel extending therethrough. To regulate a speed of the pipeline pig, relief valves within the relief channels open when a differential pressure between upstream and downstream ends of the pipeline pig reaches a pre-selected minimum relief pressure. If the differential pressure reaches a pre-selected maximum relief pressure, such as when the pipeline pig encounters an obstruction, the relief valves close to allow the differential pressure to further increase to clear the obstruction. If the further increase in differential pressure is insufficient to clear the obstruction and the differential pressure reaches a pre-selected minimum bypass pressure, a bypass valve opens to permit fluid flow through the bypass channel while the relief valves are closed. Flow through the bypass channel operates to reduce turbulence and permit production through the pipeline if the pipeline pig becomes stuck and obstructs the pipeline.

Embodiments provide a housing defining a trailing end, a leading end and longitudinal axis extending therebetween, at least one relief channel extending longitudinally through the housing between the trailing end and the leading end thereof, the at least one relief channel defining an annular wall, a closure member disposed within the annular wall, the closure member operable to engage a first seat to prohibit fluid flow through the relief channel and operable to disengage the first seat to permit fluid flow through the relief channel, and an annular space defined between the closure member and the annular wall, the annular space exhibiting a smaller cross-section than regions of relief channel upstream and downstream of the closure member such that the annular space represents a constriction for fluid flow and the relief channel defines a venturi.