Patent Application
20150139735
This disclosure relates generally to offshore pipelines, and more specifically to methods and apparatus for responding to failures in offshore submerged pipelines.
In offshore pipeline installations, as the pipeline is laid on the sea floor the pipeline is subjected to significant forces and moments that can compromise the integrity of the pipeline and, in some cases, cause failures. In the event the submerged pipeline is compromised to the point of failure, water rushes into the pipeline. Such failures are commonly referred to as wet buckles. Once a wet buckle occurs the flooded pipeline is too heavy to retrieve for repair and re-installation.
Companies that lay the pipeline keep a fleet of compressor ships on standby while the pipeline is being laid on the sea floor in case of a failure like a wet buckle. The compressor ships are present to pump the water out of the pipeline to facilitate repair of the buckled section, by allowing the pipeline to be pulled back to the surface, to the pipelay vessel, for removal of the damaged section. After the water has been removed, sections of the damaged pipeline can be retrieved and brought to the surface and the pipelay vessel can continue laying pipe onto the sea floor.
Pipeline failures like wet buckles are relatively rare. As such, during installation, the fleet of compressor ships hired by the pipeline installation company is generally inactive and serves no function for the installation process unless the rare failure occurs. The cost of the compressor ships and the associated service the ships and crew provide can reach the millions of dollars.
In view of the foregoing costs and other inefficiencies associated with recovering from an offshore pipeline failure, examples according to this disclosure are directed to methods and apparatus for automatically responding to water invasion into the inner diameter of pipe in an offshore pipeline and rapidly deploying a sealing system that will prevent or inhibit the laid pipeline from being flooded with water.
A packer apparatus in accordance with this disclosure is configured to be arranged within and arrest a failure of a submerged pipeline. In one example, the packer apparatus includes an actuator disk in axial moveable relation with a mandrel, an elastomeric expansion boot arranged between the actuator disk and the mandrel, and a brake pivotally connected to the mandrel. The actuator disk is configured to be actuated by fluid pressure within the pipeline to move axially toward the mandrel from a first position to a second position. In the second position, the actuator disk is configured to cause the expansion boot to be compressed axially between the actuator disk and the mandrel and to be radially expanded into engagement with an inner surface of the pipeline, and the brake to pivot relative to the mandrel, which causes the brake to move radially outward into engagement with the inner surface of the pipeline.
In the following examples, the apparatus for arresting pipeline wet buckles (and other pipeline failures) is referred to as a wet buckle packer. However, the apparatus could also be referred to as a plug, a shutoff pig, a baffle, or other terms connoting a device that restricts, and ideally prevents fluid flow through an annular pipeline.
Wet buckle packers in accordance with this disclosure provide a number of functions once actuated. Packer apparatus in accordance with this disclosure are sometimes referred to as configured to arrest a failure like a wet buckle in a submerged pipeline. Arresting a failure in a pipeline includes a number of different functions. In both dry and wet buckles, for example, the pipeline failure can include a structural failure including a buckle that causes the pipeline to at least partially collapse on itself. The structural buckle can run along the length of the pipeline unless it is arrested. In wet buckles, water also invades the inner diameter of the pipe causing the pipeline to become flooded. Packer apparatus in accordance with this disclosure can function to arrest both a structural buckle in a submerged pipeline, whether from a dry or wet buckle, and deploy a sealing system that will prevent or inhibit the laid pipeline from being flooded with water in the event of a wet buckle. Additionally, the packer deploys a braking mechanism to prevent or inhibit the packer from moving within the pipeline under the significant pressures introduced by the sea (or fresh) water entering the pipe from the wet buckle.
As noted above, wet buckle packers in accordance with this disclosure are configured to be automatically actuated to seal the pipeline inner diameter from ingress of water. The mechanisms for sealing and braking employed in a wet buckle packer can be actuated in a variety of ways. For example, electrical, hydraulic, or pneumatic supply lines can be run from the pipelay vessel on the surface to the packer. However, deploying supply lines from the surface downpipe to the packer will add cost and complexity to the system. The wet buckle packer could also include a power source, e.g., a battery that could be used to actuate the seal and brake mechanisms. However, the inclusion of a battery or other power source to actuate the packer will add cost and complexity to the device. In some cases, therefore, wet buckle packers are believed to be better configured to automatically actuate without the use of a power source or external actuation generator like a supply line run downpipe from the surface. As a result, while power sources or external actuation may be used in association with wet buckle packers as described herein, the examples of this disclosure are in accordance with what is believed to be the better configuration, where no such power or external source is necessary for actuation.
Wet buckle packers in accordance with this disclosure provide a new approach to seal and anchor a packer-type plug in place within a pipeline in the event of a wet buckle. The packers are designed to provide increased durability and to include component parts that protect against external variances. Example wet buckle packers can provide a number of advantages including, e.g., removing the high cost of air compressor standby in submerged pipeline installations and providing a simple and cost effective device for arresting failures in the pipeline.
Two methods that are employed to install submerged pipelines are the “J” lay and the “S” lay. The moniker of each method represents the shape of the pipeline as it is pulled off of the pipelay vessel onto the sea floor. In a “J” lay, the pipeline is pulled off of the pipelay vessel substantially vertically to near the sea floor, where the pipeline bends to run horizontally along the floor. In an “S” lay, the pipeline is pulled off of the pipelay vessel substantially horizontally, bends vertically down toward the sea floor and then bends back horizontally away from the vessel to run along the sea floor. Although the following examples are described in the context of an “S” lay installation, wet buckle packers in accordance with this disclosure can also be employed in a “J” lay installation system or other pipeline installation methods not cover here.
Pipelay vessel 12 is shown floating in a body of water 24. Pipelay vessel 12 utilizes crane 20 to perform heavy lifting operations, including loading pipes from a cargo ship onto the vessel. In general, individual pipes on board pipelay vessel 12 are placed on an assembly line within production factory 16 and joints of the pipes are welded into pipeline 14. Pipeline 14 is held in tension between sea floor 26 and pipelay vessel 12 by pipeline tensioners 18 as the pipeline is lowered. As pipelay vessel 12 moves forward by pulling on a mooring system off of the bow, pipeline 14 is lowered from pipelay vessel 12 over stinger 22. Stinger 22 is attached to and extends from the stern of pipelay vessel 12, and provides support for pipeline 14 as it leaves pipelay vessel 12.
In practice, a cargo ship transports pipe sections (sometimes referred to as stands) to pipelay vessel 12. Crane 20 moves pipe sections from the cargo ship to pipelay vessel 12 onto cradles that form a conveyor system for moving pipe into production factory 16. Within production factory 16, a number of different operations are carried out to prepare and join pipe sections. For example, the pipe ends are beveled (and bevels are deburred). The pipe ends are preheated within production factory 16 and moved through a number of welding stations to join different sections with weld beads applied both to the outer and inner diameters of the sections at the joints. In some cases, a final welding station within production factory 16 applies a welded cap to the joints of pipe sections.
The joints of the welded pipe sections can also be tested within production factory 16. For example, the welded joints can pass through ultrasonic testing stations that apply water to the joints as the medium to transmit the ultrasonic signals. The ultrasonic signals can be processed by a computing system and graphically displayed for inspection by an operator.
After testing, the joints of the welded pipe sections can be grit blasted and a field joint coating can be applied. In some installation systems, each individual pipe is subjected to this process as it is welded to pipeline 14. In other cases, multiple pipes, e.g. two pipes in a double stand facility, are first welded together and then welded to the pipeline in the firing line onboard pipelay vessel 12. At any rate, the assembled pipeline 14 is ultimately conveyed through tensioners 18 and over stinger 22 to be dropped off of the stern of pipelay vessel 12 to sea floor 26.
As pipeline 14 is laid on sea floor 26, suspended pipe span 28 forms a shallow “S” shape between sea floor 26 and pipelay vessel 12. The “S” shape of suspended pipe 28 is sometimes referred to as the S-curve. Second curve 30 or the tail of the S-curve just before suspended pipe span 28 meets sea floor 26 is sometimes referred as the “sagbend.” The S-curve of pipeline 14 is controlled by stinger 22 and pipeline tensioners 18. Increases in the curvature of pipeline 14 cause increases in the bending moment on the pipeline, and, as a result, higher stresses. High stresses on pipeline 14 and, in particular, on suspended pipe span 28 can result in buckling of the pipeline 14. For example, a loss of tension in pipeline 14 during the pipe lay will normally cause pipeline 14 to buckle at a point along the suspended pipe span 28. A buckle in pipeline 14 is called a wet buckle if pipeline 14 has cracked or becomes damaged in manner such that water is allowed to enter the inner diameter of the pipeline. The influx of water into the pipeline 14 greatly increases the weight of suspended pipe span 28 such that the pipe can become over stressed at a location along suspended pipe span 28, generally near stinger 22. In such circumstances, flooded pipeline 14 can break and drop from pipelay vessel 12 to sea floor 26. Regardless of whether pipeline 14 breaks in the event of a wet buckle, the increased weight can prevent recovery of and repair to pipeline 14 before the water is pumped out of the pipeline.
Examples according to this disclosure are directed to a wet buckle packer that can be deployed within the inner diameter of pipeline 14 as it is laid on sea floor 26. In
Wet buckle packers 32 and 34 are configured to automatically respond to water invasion into the inner diameter of pipeline 14 and rapidly deploy a sealing system that will prevent the laid pipeline and pipeline above packer 32 from being flooded with sea water. For example, wet buckle packers 32 and 34 seal the inner diameter of pipeline 14 to prevent or significantly inhibit water from flooding the submerged pipeline. Additionally, wet buckle packers 32 and 34 deploy a braking mechanism to prevent or inhibit the packers from moving within pipeline 14 as a result of the pressures introduced by the sea water entering the pipe from the wet buckle.
In some cases one or more “piggy-back” lines may be laid from pipelay vessel 12 along with main pipeline 14. Piggy-back lines are generally constructed from smaller diameter pipes that are assembled in a similar manner as described above with reference to pipeline 14. The piggy-back lines are assembled in parallel with and are then coupled to pipeline 14, e.g., with a sleeve connected to top of the main pipeline 14 in which the piggy-back lines are received.
Packer 100 is configured to be deployed from a pipelay vessel down a submerged pipeline via hoist line 112. Packer 100 can be lowered into an already submerged pipeline or can be lowered along with a particular section of the pipeline as it is dropped to the sea floor. The generally cylindrical shape of packer 100 defined by the outer peripheries of perforated cylinder 104, actuator disk 106, expansion boot 108, and brake assembly 110 is configured to slide within the pipeline as packer 100 is deployed downpipe from the pipelay vessel.
Packer 100 can be deployed at a number of locations within the submerged pipeline to arrest pipeline failures like wet buckles. For example, packer 100 can be deployed along a suspended pipe span of the pipeline or further downpipe where the pipeline meets the sea floor. Wet buckle packer 100 is configured to automatically respond to water invasion into the inner diameter of the pipeline and rapidly deploy a sealing system that will prevent the laid pipeline and pipeline above packer 32 from being flooded with sea water, which is described in more detail with reference to
Hoist line 112 extends from hoist ring 102 up to, for example, a hoist machine on a pipelay vessel. In some examples, packer 100 can include hoist rings on both ends of the device to deploy multiple packers within a pipeline in space, series relation within the pipeline. Packer 100 is configured to be arranged within the pipeline such that the end including cylinder 104 faces the region of the pipeline that is at risk of a wet buckle (or other failure). Thus, in the example of
In this example, the packer deployed closer to the surface would be arranged within suspended pipe span 28 such that perforated cylinder 104 faces down toward the likely location of the wet buckle in the sagbend. This upper packer could include a hoist line running from the end of the device including the brake and another line running from the perforated cylinder to the lower packer. The lower packer closer to sea floor 26 would be arranged within the pipeline such that the perforated cylinder faces up toward the likely location of the wet buckle in the sagbend and the lower packer would be connected to the upper packer by the line coupled to the perforated cylinders of each device.
Actuator disk 106 is a frustoconical disk with tapered outer surface 118. Actuator disk includes thru holes 120 and central thru hole 122. Thru holes 120 are configured to receive posts 114 protruding from the end of cylinder 104. Central thru hole 122 is configured to receive central post 116 of cylinder 104. In another example, the actuator disk of a packer in accordance with this disclosure can have a different shape, including, e.g., cylindrical.
As illustrated in
Expansion boot 108 includes rounded edges 134, central thru hole 136, and thru holes 138. Expansion boot 108 is configured to be arranged between end plate 126 of spindle 124 and brake assembly 110. Central thru hole 136 is configured to receive central shaft 128 of spindle 124 and thru holes 138 are configured to receive posts 114 protruding from the end of cylinder 104.
Brake assembly 110 includes brake mandrel 142, expansion wing 144, brake clevis 146, lever 148, and brake pad 150. Brake mandrel 142 includes end plate 154 with central thru hole 158. Central thru hole 158 is configured to receive central shaft 128 of spindle 124. Brake mandrel 142 also includes a plurality of clevises 160 disposed at different angularly disposed, circumferential positions about a longitudinal axis of packer 100. Expansion wing 144 of brake assembly 110 includes central shaft 162 and wings 164 protruding radially outward from shaft 162. Wings 164 are disposed at different angular positions about the circumference of central shaft 162. Shaft 162 is configured to receive central shaft 128 of spindle 124. Brake pad 150 has an arcuate shape and includes clevis 166 extending radially inward from the inner surface of pad 150. Additionally, the outer surface of brake pad 150 includes a saw-tooth profile defined by a series of circumferentially extending ridges, which are configured to engage the inner surface of pipeline 170 without slipping. In many examples, the ridges will not be symmetrical, but will be configured particularly to prevent movement in the direction toward the end of packer 100 including brake assembly 110 (i.e., away from the likely location of water influx due to a wet buckle). In one example, pad 150 is manufactured from steel and, in some cases, can include carbide buttons that form the saw-tooth profile of pad 150.
Packer 100 also includes a locking mechanism including ratchet pawl 152 and ratchet teeth 168 in a portion of the outer surface of central shaft 128 of spindle 124. The configuration and function of the locking mechanism is described in detail below with reference to
Actuator disk 106, expansion boot 108, spindle 124, and brake mandrel 142 are axially aligned along axis 172 of packer 100. Expansion boot 108 is arranged between end plate 126 of spindle 124 and brake mandrel 142. Actuator disk 106 is arranged between perforated cylinder 104 and end plate 126 of spindle 124.
Central post 116 of cylinder 104 passes through actuator disk 106. Central shaft 128 of spindle 124 passes through expansion boot 108, brake mandrel 142, and into shaft 162 of expansion wing 144.
As noted above, brake assembly 110 includes brake mandrel 142, expansion wing 144, brake clevis 146, lever 148, and brake pad 150. Central shaft 128 of spindle 124 is received in central shaft 162 of expansion wing 144. Expansion wing 144 is configured to move axially as spindle 124 is pushed on by actuator disk 106. Brake clevises 146 and levers 148 are pivotally connected between wings 164 of expansion wing 144 and clevises 160 of brake mandrel 142. In particular, brake clevises 146 are pivotally connected to wings 164 at pivot 174 and to levers 148 at pivot 176. Levers 148 are pivotally connected to clevises 160 of brake mandrel 142 at pivot 178 and to clevises 166 of brake pads 150 at pivot 180. An expansion wing 144 is moved axially by spindle 124, brake clevises 146 and levers 148 pivot and levers 148 push brake pads 150 radially outward to engage the inner surface of pipeline 170, and to set brake assembly 110. As illustrated in
Packer 100 is configured to be automatically actuated in the event of a wet buckle of pipeline 170. In such an event, water invades pipeline 170 and flows through the inner diameter of the pipe toward cylinder 104. Actuator disk 106 is configured to freely move axially relative to cylinder 104. Without the application of an external force like the pressure produced by water in pipeline 170, expansion boot 108 maintains actuator disk 106 in relatively close proximity to cylinder 104, as illustrated in
As the pressure of the water pushes actuator disk 106 away from cylinder 104, actuator disk 106 compresses axially and expands radially expansion boot 108 and sets brake assembly 110, as illustrated in
Expansion boot 108 is an elastomeric boot, which in some examples, can be hollow to reduce weight or improve expansion of boot 108 into engagement with pipeline 170. Rounded edges 134 of expansion boot 108 may be configured to bias expansion boot 108 to move radially outward, instead of inward, when boot 108 is compressed axially between end plate 126 of spindle 124 and end plate 154 of brake mandrel 142.
As illustrated in
In some examples, packer 100 can include an actuator that either augments the effect of the water pressure on actuator disk 106 or is employed in lieu of automatic actuation by the water pressure. For example, in the event the water pressure fails to actuate the device, packer 100 could include an actuator that drives actuator disk 106 and/or spindle 124 to seal pipeline 170 via expansion boot 108 and to set brake assembly 110. Example actuators that could be employed with packer 100 include a variety of mechanical and electromechanical devices that are configured to be actuated to drive actuator disk 106. For example, an actuator employed in packer 100 or other packers in accordance with this disclosure can include a pneumatically or hydraulically actuated piston that drives actuator disk 106 and/or spindle 124 with air or a hydraulic fluid supplied by a supply line running from the pipelay vessel. In another example, an actuator includes an electrically activated solenoid that drives actuator disk 106 and/or spindle 124. In another example, an actuator includes an electromagnetic piston that drives actuator disk 106 and/or spindle 124 based on controlled electricity transmitted to packer 100 via a supply line connected to the actuator.
In some examples, packer 100 can include a sensor system that detects the invasion of water into the inner diameter of pipeline 170. In another example, the sensor system can be associated with a separate component and be communicatively coupled to packer 100. In one example, the sensor system includes a water sensor including two spaced electrodes arranged within pipeline 170 such that water invading the pipeline would complete an electrical circuit of the sensor. In another example, a pressure sensor could be used to detect the invasion of water into the inner diameter of pipeline 170. The sensor system communicatively coupled to packer 100 can provide a signal directly to control electronics included in an actuator of packer 100 or can transmit signals to a surface system, which, in turn, transmits control signals to an actuator via a supply line. Wet buckle detection via such a sensor system could be employed to test or verify whether packer 100 is actuated and, in some examples, could be used as a trigger to activate an actuator included in packer 100.
In conjunction with axial movement of actuator disk 106 to cause expansion boot 108 to engage pipeline 170, brake assembly 110 is also deployed to prevent or substantially inhibit movement of packer 100 within pipeline 170. For example, as the pressure of the water strikes actuator disk 106, actuator disk 106 pushes spindle 124 axially away from cylinder 104 toward brake mandrel 142. Central shaft 128 of spindle 124 moves expansion wing 144 axially away from cylinder 104. Axial movement of expansion wing 144 causes wings 164 to move brake clevises 146. Brake clevises rotate about pivot 174 and pivot 176 and cause levers 148 to rotate about pivot 178. Levers 148 rotating about pivot 178 cause levers 148 to push brake pads 150 radially outward into engagement with the inner surface of pipeline 170.
Packer 100 is configured such that in the unengaged state illustrated in
Although particular offset distances are described with reference to example packer 100, a packer in accordance with this disclosure will be constructed with a desired dimensional relationship with the dimensions of the pipeline in which the device is to be used. In one example configuration, a radial clearance of approximately ⅛ inch will separate the sealing element of the packer and the pipeline inner surface and a radial clearance of approximately ¼ inch will separate the braking element of the packer and the pipeline inner surface. However, as will be apparent to persons skilled in the art, different radial dimensions may be used for any size pipe, and in some cases such dimensions may be determined by other factors, such as the designed radius of bends the pipeline will experience while being installed on the sea floor, and/or the intended characteristic of the internal welds used to join the pipeline sections.
In some cases, it may be desirable to configure packer 100 such that offset 182 between expansion boot 108 and the inner surface of the pipeline 170 is as small as possible while still allowing packer 100 to be deployed downpipe within pipeline 170. In one example, the outer periphery of expansion boot 108 is configured to nearly abut the inner surface of pipeline 170 even in the unengaged state of packer 100. In practice, there may be a delay between the occurrence of a wet buckle to pipeline 170 and water striking actuator disk 106 to cause packer 100 to become engaged with the inner surface of pipeline 170. During the delay in actuation of packer 100 some water may pass through packer 100. Reducing offset 182 between expansion boot 108 and the inner surface of the pipeline 170 will reduce the amount of water that floods pipeline 170 before packer 100 is engaged and expansion boot 108 substantially seals the inner diameter of the pipeline. Additionally, the outer periphery of actuator disk 106 can abut or nearly abut the inner surface of pipeline 170 to provide a kind of preliminary seal of the pipeline before packer 100 becomes completely engaged.
As is illustrated in
The overall weight of packer 100 also affects the amount of load on hoist line 112 and, as a result, the amount of work required by the hoist machine operating hoist line 112. As such, reducing the weight of packer 100 can also reduce the cost and complexity of deploying packer 100 via hoist line 112.
The forces encountered by packer 100 in the event of a wet buckle of pipeline 170 may be significant. For example, at a relatively shallow depth of approximately 1500 feet below sea level, the pressures generated by a wet buckle can reach approximately 660 pounds per square inch (psi). At a depth of approximately 12,000 feet, the pressures generated by a wet buckle can reach approximately 5280 psi. In view of the range of forces potentially encountered by wet buckle packer 100, the wall thicknesses of the components of packer 100 may need to be adjusted to withstand large forces/pressures.
Forces encountered by different portions of packer 100 may differ significantly. For example, portions of packer 100 may be partially or substantially pressure balanced because water introduced into pipeline 170 is allowed to enter parts of packer 100. In such situations, the pressure of the water is balanced on particular portions of packer 100. For example, water may be allowed to enter portions of packer 100 such that the water pressure is balanced on either side of a wall of cylinder 104. In some examples, therefore, packer 100 may be designed to allow pressure balancing of some portions of the device such that the wall thicknesses of different portions of cylinder 104, and other components of packer 100 may differ significantly depending on the amount of pressure/force encountered in the event of a wet buckle.
A variety of materials can be used to fabricate the components of packer 100 including, e.g., metals, plastics, elastomers, and composites. For example, cylinder 104, spindle 124, brake mandrel 142, expansion wing 144, brake clevises 146, brake pads 150, and levers 148 can be fabricated from a variety of different types of steel or aluminum. Actuator disk 106 and expansion boot 108 can be fabricated from a variety of elastomeric materials including rubber. In one example, actuator disk 106 and/or expansion boot 108 are fabricated from a nitrile rubber. At the sea floor, packer 100 may encounter temperatures as low as 32 degrees Fahrenheit (0 degrees Celsius). As such, actuator disk 106 and expansion boot 108 may need to be fabricated from elastomers that can withstand relatively low temperatures without significantly affecting the material properties of the components. For example, expansion boot 108 may need to be fabricated from elastomers that can withstand relatively low temperatures without causing boot 108 to become too hard, stiff and/or brittle such that the disks are incapable of sufficiently sealing the inner diameter of pipeline 170. The components of packer 100 can be fabricated using a variety of techniques including, e.g., machining, injection molding, casting, and other appropriate techniques for manufacturing such parts.
Packer 100 also includes a locking mechanism including ratchet pawl 152 and ratchet teeth 168 in a portion of the outer surface of central shaft 128 of spindle 124.
Locking mechanism 200 includes a plurality of ratchet pawls 152. Ratchet pawls 152 are connected to brake mandrel 142 and are disposed at different angularly disposed, circumferential positions about a longitudinal axis of packer 100. Different numbers of pawls 152 can be employed to act in conjunction with ratchet teeth 168 to lock brake assembly 110. For example, two ratchet pawls 152 can be arranged approximately 180 degree offsets from one another about the longitudinal axis of packer 100. In another example, three pawls 152 can be arranged approximately 120 degree offsets from one another about the longitudinal axis of packer 100. In another example, four pawls 152 can be arranged approximately 90 degree offsets from one another about the longitudinal axis of packer 100. In some examples, a number of ratchet pawls 152 can be disposed at angularly disposed, circumferential positions about the longitudinal axis of packer 100 such that the pawls are unequally spaced from one another.
Each pawl 152 includes slot 202. Slot 202 is sized to accommodate a spring (not shown) or other biasing mechanism that biases ratchet pawl 152 radially inward toward ratchet teeth 168 in shaft 128 of spindle 124. As actuator disk 106 pushes spindle 124 (down in the view of
Packer 100 is actuated in response to and as a result of water ingress into the pipeline. For example, actuating packer 100 can include moving actuator disk 106 axially toward brake mandrel 142 from a first position to a second position. Actuator disk 106 is moved from the first to the second position as a result of fluid pressure generated by the water in the pipeline. In the second position, actuator disk 106 causes expansion boot 108 to be compressed axially between actuator disk 106 and brake mandrel 142, which causes expansion boot 108 to be radially expanded into engagement with an inner surface of the pipeline. Additionally, in the second position, brake assembly 110 pivots relative to brake mandrel 142, which causes brake assembly 110 to move radially outward into engagement with the inner surface of the pipeline.
As described above, methods of arresting wet buckles and other failures of a submerged pipeline can include deploying multiple packers within the submerged pipeline. In one example, the packers are deployed on either side (e.g. one closer to the surface and one farther from the surface and closer to the sea floor) of the likely location of the wet buckle (or other failure). In such examples, both packers can be actuated to seal the region of the pipeline between the packers and including the location of the failure.
As described above, the method of
Various examples have been described. These and other examples are within the scope of the following claims.
