CA2605728C - Pipe end sealing tool - Google Patents
Pipe end sealing tool Download PDFInfo
- Publication number
- CA2605728C CA2605728C CA2605728A CA2605728A CA2605728C CA 2605728 C CA2605728 C CA 2605728C CA 2605728 A CA2605728 A CA 2605728A CA 2605728 A CA2605728 A CA 2605728A CA 2605728 C CA2605728 C CA 2605728C
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- CA
- Canada
- Prior art keywords
- lock
- seal
- tool
- pipe
- wall
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/022—Test plugs for closing off the end of a pipe
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/10—Means for stopping flow from or in pipes or hoses
- F16L55/11—Plugs
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/10—Means for stopping flow from or in pipes or hoses
- F16L55/11—Plugs
- F16L55/1141—Plugs the plug being made of elastic material
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/10—Means for stopping flow from or in pipes or hoses
- F16L55/115—Caps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/10—Means for stopping flow from or in pipes or hoses
- F16L55/115—Caps
- F16L55/1157—Caps using hooks, pawls, or other movable or insertable locking members
Abstract
A pipe end-sealing tool comprises a body. A seal is mounted on the body and is adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed. A lock is also mounted on the body and is adapted to engage an outer wall of the pipe end. Thus, a load applied to the pipe wall by the lock opposes the sealing pressure.
Description
PIPE END SEALING TOOL
FIELD OF THE INVENTION
This invention relates to a pipe end sealing tool, such as a pipe end plug.
The tool may be utilised to seal the end of a pipe or tube to permit, for example, the pressure integrity of the pipe to be tested.
BACKGROUND OF THE INVENTION
In many industries there is a requirement to pressure test pipes, tubes, pipe modules, pipelines and the like. For example, in the oil and gas industry, some process plant is assembled from modules, which are welded together on site.
The pipe weldments in these modules must be pressure tested prior to shipping to site.
The first step in the pressure testing process is the sealing of the open end of the tubing. At present, this is achieved by one of: welding a cap on to the tubing;
inserting an isolation plug into the end of the tubing; or by sliding a mechanical cap over the end of the tubing.
Welding a cap on to the tubing is expensive and time consuming.
Furthermore, once the test is complete, the cap must be cut off.
The use of an internal isolation plug requires provision of a plug with a locking mechanism and seal. This requires a straight length of pipe to accommodate the plug, and thus may require a straight spool to be welded to the pipe to accommodate the plug. Furthermore, steel pipe tends to be supplied in standard outside diameters, but internal diameters may vary. Accordingly, internal plugs must be dressed or sized to suit the particular internal diameter of the tubing under test. This is particularly important for the plug locking mechanism, where an incorrect sizing selection may reduce the ability of the plug to resist the test pressure load, which load will tend to eject the plug from the tubing if not resisted.
In the case of self-energised plugs in which the test pressure energises the plug sealing and lock mechanisms, the loads generated by the test pressure are transferred to the tubing, causing peak hoop stress at the seal and lock contacts. Accordingly, the tube end must be assessed for each application, to ensure that the tubing wall will accommodate the anticipated hoop stress.
FIELD OF THE INVENTION
This invention relates to a pipe end sealing tool, such as a pipe end plug.
The tool may be utilised to seal the end of a pipe or tube to permit, for example, the pressure integrity of the pipe to be tested.
BACKGROUND OF THE INVENTION
In many industries there is a requirement to pressure test pipes, tubes, pipe modules, pipelines and the like. For example, in the oil and gas industry, some process plant is assembled from modules, which are welded together on site.
The pipe weldments in these modules must be pressure tested prior to shipping to site.
The first step in the pressure testing process is the sealing of the open end of the tubing. At present, this is achieved by one of: welding a cap on to the tubing;
inserting an isolation plug into the end of the tubing; or by sliding a mechanical cap over the end of the tubing.
Welding a cap on to the tubing is expensive and time consuming.
Furthermore, once the test is complete, the cap must be cut off.
The use of an internal isolation plug requires provision of a plug with a locking mechanism and seal. This requires a straight length of pipe to accommodate the plug, and thus may require a straight spool to be welded to the pipe to accommodate the plug. Furthermore, steel pipe tends to be supplied in standard outside diameters, but internal diameters may vary. Accordingly, internal plugs must be dressed or sized to suit the particular internal diameter of the tubing under test. This is particularly important for the plug locking mechanism, where an incorrect sizing selection may reduce the ability of the plug to resist the test pressure load, which load will tend to eject the plug from the tubing if not resisted.
In the case of self-energised plugs in which the test pressure energises the plug sealing and lock mechanisms, the loads generated by the test pressure are transferred to the tubing, causing peak hoop stress at the seal and lock contacts. Accordingly, the tube end must be assessed for each application, to ensure that the tubing wall will accommodate the anticipated hoop stress.
2 The use of externally mounted mechanical caps removes the dressing requirement for each tubing bore, as pipe is normally specified by outside diameter, but as the cap seals engage the outer wall surface of the tubing, and thus encompass a larger area, the ejection load experienced by a cap is greater than that experienced by a corresponding plug. Caps also tend to be heavier and require even longer lengths of straight pipe than a corresponding plug. Furthermore, the cap locks and seals create localised stresses on the tubing wall, such that the tubing wall condition must always be carefully assessed.
SUMMARY OF THE INVENTION
According to the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
According to another aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, whereby a radial load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
Thus, the load applied to the pipe outer diameter by the lock is supported by the seal pressure, and vice versa. This avoids the problems experienced with conventional internal plugs and conventional externally-mounted caps, in which the sealing pressure and lock loads act in a common direction, placing potentially large
SUMMARY OF THE INVENTION
According to the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
According to another aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, whereby a radial load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
Thus, the load applied to the pipe outer diameter by the lock is supported by the seal pressure, and vice versa. This avoids the problems experienced with conventional internal plugs and conventional externally-mounted caps, in which the sealing pressure and lock loads act in a common direction, placing potentially large
3 unbalanced loads on the pipe wall. Also, the separation of the sealing and locking arrangements facilitates provision of a more compact arrangement, and embodiments of the invention have been produced which are approximately half the length of a conventional plug or cap.
The seal may take any appropriate form, and in one embodiment the seal comprises a compression seal. Radial movement of a sealing surface of the seal and a sealing pressure may be produced by axial compression of the seal. The seal may comprise an elastomeric seal element. In one embodiment, an annular seal element is provided on a mandrel or core between opposing compression faces, the faces being relatively movable to compress the element and induce radial expansion of the element.
The seal may be self-energised. Once a minimum pressure differential is achieved across the seal, the internal pipe pressure will tend to maintain the seal in the energised configuration, independently of the status of the seal actuation system, such that the seal is fail-safe.
The lock may take any appropriate form. Lock members may be provided and be adapted to be selectively urged into engagement with the wall of the pipe.
The lock may comprise a taper lock. A lock member may comprise an inclined surface and be operatively associated with a relatively movable cooperating member with a corresponding inclined surface. The lock member may feature teeth or some other surface configuration for gripping the pipe wall surface.
The lock may be configured such that an ejection load on the tool serves to increase the grip of the lock on the pipe wall surface, that is the lock may be self-energised. The ejection load path through the tool may be arranged to bypass the lock actuation system. This may facilitate avoiding overloading of the system and ensure that the self-energising feature is effective in the event of an actuating system failure.
The seal and lock may be actuated separately, or may be actuated by a common actuation system or arrangement. The seal and lock may be actuated by any appropriate mechanism, for example by bolts, torque, or by induction. In one embodiment, one or both of the seal and lock are fluid actuated, and may be hydraulically actuated, although pneumatic actuation may also be utilised.
The lock may be energised or actuated prior to energising or actuating the seal, ensuring that the tool is locked to the pipe end before pressure is applied across the tool.
The seal may take any appropriate form, and in one embodiment the seal comprises a compression seal. Radial movement of a sealing surface of the seal and a sealing pressure may be produced by axial compression of the seal. The seal may comprise an elastomeric seal element. In one embodiment, an annular seal element is provided on a mandrel or core between opposing compression faces, the faces being relatively movable to compress the element and induce radial expansion of the element.
The seal may be self-energised. Once a minimum pressure differential is achieved across the seal, the internal pipe pressure will tend to maintain the seal in the energised configuration, independently of the status of the seal actuation system, such that the seal is fail-safe.
The lock may take any appropriate form. Lock members may be provided and be adapted to be selectively urged into engagement with the wall of the pipe.
The lock may comprise a taper lock. A lock member may comprise an inclined surface and be operatively associated with a relatively movable cooperating member with a corresponding inclined surface. The lock member may feature teeth or some other surface configuration for gripping the pipe wall surface.
The lock may be configured such that an ejection load on the tool serves to increase the grip of the lock on the pipe wall surface, that is the lock may be self-energised. The ejection load path through the tool may be arranged to bypass the lock actuation system. This may facilitate avoiding overloading of the system and ensure that the self-energising feature is effective in the event of an actuating system failure.
The seal and lock may be actuated separately, or may be actuated by a common actuation system or arrangement. The seal and lock may be actuated by any appropriate mechanism, for example by bolts, torque, or by induction. In one embodiment, one or both of the seal and lock are fluid actuated, and may be hydraulically actuated, although pneumatic actuation may also be utilised.
The lock may be energised or actuated prior to energising or actuating the seal, ensuring that the tool is locked to the pipe end before pressure is applied across the tool.
4 The tool may feature a fill/vent port, and this port may extend through a tool core. Where the tool is intended to be utilised in horizontal applications, the port may be configured, for example by provision of an internal elbow, to provide a high point vent.
The tool may comprise a dual seal feature, whereby a volume between two seals can be pressurised and monitored to allow the integrity of the seal to be verified before pressurising the pipe.
The various features and options listed above may have utility independently of the aspects of the invention described above, and may form separate aspects of the invention. In particular, the self-energising seal and lock features, and the fail-safe seal and lock features, may form separate aspects of the invention.
According to a further aspect of the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
According to a further aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, whereby load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
According to a further aspect of the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing
The tool may comprise a dual seal feature, whereby a volume between two seals can be pressurised and monitored to allow the integrity of the seal to be verified before pressurising the pipe.
The various features and options listed above may have utility independently of the aspects of the invention described above, and may form separate aspects of the invention. In particular, the self-energising seal and lock features, and the fail-safe seal and lock features, may form separate aspects of the invention.
According to a further aspect of the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
According to a further aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, whereby load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
According to a further aspect of the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing
5 pressure.
According to a further aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention, there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and
According to a further aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention, there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and
6 a lock mounted on the body and adapted to engage an outer wall of the pipe end, wherein at least one of the seal and the lock is fluid actuated and whereby load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention, there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention, there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention, there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
BRIEF DESCRIPTION OF THE DRAWING
The figure is a sectional view of a pipe end sealing tool in accordance with a preferred embodiment of the present invention, the top half of the figure illustrating the tool in a fitting and retrieval configuration, and the lower half of the figure illustrating the tool in an energised configuration.
According to a further aspect of the present invention, there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention, there is provided a pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
According to a further aspect of the present invention, there is provided a method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
BRIEF DESCRIPTION OF THE DRAWING
The figure is a sectional view of a pipe end sealing tool in accordance with a preferred embodiment of the present invention, the top half of the figure illustrating the tool in a fitting and retrieval configuration, and the lower half of the figure illustrating the tool in an energised configuration.
7 DETAILED DESCRIPTION OF THE DRAWING
The drawing illustrates a pipe end sealing tool 10 in accordance with a preferred embodiment of the present invention. The figure shows the tool 10 in section, the upper half of the figure illustrating the tool 10 in a fitting and retrieval configuration, while the lower half of the figure illustrates the tool 10 in an activated or energised configuration. The tool 10 may be utilised to close and seal the end of any appropriate pipe or tube, and is ideally suited for use in testing prefabricated pipe spools and the like, as used in the oil and gas industry. The tool is shown mounted on the end of a length of plain pipe 12, in this example the pipe being the end of a pipe spool.
The tool 10 comprises a body 14 providing mounting for a compression seal 16, adapted to engage the inner pipe wall 18, and a taper lock 20, adapted to engage the outer pipe wall 22.
The compression seal 16 comprises an annular rubber seal element 24.
Mounting for the element 24 is provided by a mandrel or core 26. The core 26 is in two parts, the element 24 being mounted on a flanged sleeve 28 which is threaded to a carrier 30. A fill/vent port 32 extends through the carrier 30, to allow the interior of the pipe to be pressurised and vented.
While the inner end face and inner diameter of the element 24 are contained by the flanged sleeve 28 mounted on the carrier 30, the outer end face of the element 24 is contained by a face of a ported body member 34. A carrier flange 36 and a body member flange 38, provided with co-operating seals 40, 42, define a chamber 44 into which pressure may be introduced such that the carrier 30 acts as a piston to move the core 26 outwards relative to the body member 34 and the pipe end, to axially compress and radially expand the seal element 24.
The taper lock 20 comprises lock members or segments 50 adapted to engage the outer pipe wall 22. In an initial fitting and retrieval configuration, the teeth on the inner surface of the lock segments 50 are lifted clear of the pipe wall 22 by sprung pins 52, to facilitate fitting and removal of the tool 10 from the pipe end.
The end face of each lock segment 50 engages a piston sleeve 54 which co-operates with stepped outer faces of the body member 34. Seals 56, 58 create a chamber 60 to which pressurised hydraulic fluid may be supplied via the body member ports 62, to move the piston sleeve 54 and lock segments 50 relative to the body member 34.
The drawing illustrates a pipe end sealing tool 10 in accordance with a preferred embodiment of the present invention. The figure shows the tool 10 in section, the upper half of the figure illustrating the tool 10 in a fitting and retrieval configuration, while the lower half of the figure illustrates the tool 10 in an activated or energised configuration. The tool 10 may be utilised to close and seal the end of any appropriate pipe or tube, and is ideally suited for use in testing prefabricated pipe spools and the like, as used in the oil and gas industry. The tool is shown mounted on the end of a length of plain pipe 12, in this example the pipe being the end of a pipe spool.
The tool 10 comprises a body 14 providing mounting for a compression seal 16, adapted to engage the inner pipe wall 18, and a taper lock 20, adapted to engage the outer pipe wall 22.
The compression seal 16 comprises an annular rubber seal element 24.
Mounting for the element 24 is provided by a mandrel or core 26. The core 26 is in two parts, the element 24 being mounted on a flanged sleeve 28 which is threaded to a carrier 30. A fill/vent port 32 extends through the carrier 30, to allow the interior of the pipe to be pressurised and vented.
While the inner end face and inner diameter of the element 24 are contained by the flanged sleeve 28 mounted on the carrier 30, the outer end face of the element 24 is contained by a face of a ported body member 34. A carrier flange 36 and a body member flange 38, provided with co-operating seals 40, 42, define a chamber 44 into which pressure may be introduced such that the carrier 30 acts as a piston to move the core 26 outwards relative to the body member 34 and the pipe end, to axially compress and radially expand the seal element 24.
The taper lock 20 comprises lock members or segments 50 adapted to engage the outer pipe wall 22. In an initial fitting and retrieval configuration, the teeth on the inner surface of the lock segments 50 are lifted clear of the pipe wall 22 by sprung pins 52, to facilitate fitting and removal of the tool 10 from the pipe end.
The end face of each lock segment 50 engages a piston sleeve 54 which co-operates with stepped outer faces of the body member 34. Seals 56, 58 create a chamber 60 to which pressurised hydraulic fluid may be supplied via the body member ports 62, to move the piston sleeve 54 and lock segments 50 relative to the body member 34.
8 An outer sleeve or casing 64 is threaded to the body member 34 and features a taper face 66 for co-operating with corresponding lock segment taper faces 68.
Thus, when pressurised hydraulic fluid is introduced to the chamber 60, relative movement between the taper faces 66, 68 urges the lock segments 50 into locking contact with the outer pipe wall 22.
In use, the tool 10 is located on the end of a pipe 12 to be pressure tested.
The pipe wall is accommodated in the annular volume between the seal element 24 and the lock segments 50. Steel pipe is supplied in standard outside diameters, such that the components adapted to co-operate with the outer pipe wall 22 may be sized with a degree of accuracy and confidence. However, variations in pipe wall thickness and configuration, which give rise to less predictable inner pipe wall dimensions, are relatively easily accommodated by the clearance provided by the non-energised seal element 24.
To actuate or energise the tool 10, a source of pressurised hydraulic fluid is coupled to the body member ports 62, and pressurised fluid supplied to fill the chambers 44, 60, as shown in the lower half of the figure. The actuation arrangement is configured such that the lock segments 50 will be energised to grip the outer pipe wall 22 before the seal element 24 is fully energised, and comes in to contact with the inner pipe wall 18. This ensures that the lock arrangement 20 is actuated prior to the generation of a seal, ensuring that the tool 10 is securely locked on the pipe end 12 before any pressure can be applied across the tool 10.
It will be noted that the actuated lock segments 50 and the energised seal element 24 are positioned on opposing sides of the pipe wall. Accordingly, the loads applied to the pipe wall by the lock members 50 and the seal element 24 are balanced, the pressure forces created by the energised seal element 24 being supported by the energised lock members 50, and vice versa.
Once activated, the load path of the internal test pressure self-energises the tool 10, such that the isolation will be maintained, independently of the integrity of the actuation system. In particular, the internal test pressure which acts on the tool core 26 generates a force on the compression seal relative to the test pressure times the ratio of the pipe bore cross sectional area divided by the seal element cross sectional area. This load generates a rubber pressure in the seal element 24 which is higher than the pressure being isolated.
Thus, when pressurised hydraulic fluid is introduced to the chamber 60, relative movement between the taper faces 66, 68 urges the lock segments 50 into locking contact with the outer pipe wall 22.
In use, the tool 10 is located on the end of a pipe 12 to be pressure tested.
The pipe wall is accommodated in the annular volume between the seal element 24 and the lock segments 50. Steel pipe is supplied in standard outside diameters, such that the components adapted to co-operate with the outer pipe wall 22 may be sized with a degree of accuracy and confidence. However, variations in pipe wall thickness and configuration, which give rise to less predictable inner pipe wall dimensions, are relatively easily accommodated by the clearance provided by the non-energised seal element 24.
To actuate or energise the tool 10, a source of pressurised hydraulic fluid is coupled to the body member ports 62, and pressurised fluid supplied to fill the chambers 44, 60, as shown in the lower half of the figure. The actuation arrangement is configured such that the lock segments 50 will be energised to grip the outer pipe wall 22 before the seal element 24 is fully energised, and comes in to contact with the inner pipe wall 18. This ensures that the lock arrangement 20 is actuated prior to the generation of a seal, ensuring that the tool 10 is securely locked on the pipe end 12 before any pressure can be applied across the tool 10.
It will be noted that the actuated lock segments 50 and the energised seal element 24 are positioned on opposing sides of the pipe wall. Accordingly, the loads applied to the pipe wall by the lock members 50 and the seal element 24 are balanced, the pressure forces created by the energised seal element 24 being supported by the energised lock members 50, and vice versa.
Once activated, the load path of the internal test pressure self-energises the tool 10, such that the isolation will be maintained, independently of the integrity of the actuation system. In particular, the internal test pressure which acts on the tool core 26 generates a force on the compression seal relative to the test pressure times the ratio of the pipe bore cross sectional area divided by the seal element cross sectional area. This load generates a rubber pressure in the seal element 24 which is higher than the pressure being isolated.
9 Furthermore, the ejection load path through the tool 10 passes through the body member 34 and the outer casing 64 to pull on the taper of the lock segments 50, so increasing the grip of the lock 20. This load path bypasses the hydraulic actuation system, to both prevent over pressurising the system and to ensure that the loss of the actuation system would not effect the self-energisation feature.
Those of skill in the art will recognise that the above described pipe end sealing tool 10 provides a quick and reliable method of temporarily capping open pipes and tubes. The relative locations of the seal 16 and lock 20 allow the tool 10 to be relatively compact, typically half the length of a conventional mechanical plug or mechanical cap. Furthermore, the relative locations of the seal 16 and lock 20 allow the internal seal and external locking loads to balance, such that the pipe wall does not experience significant radial stresses. Furthermore, the tool 10 may be actuated quickly and easily using hydraulic fluid, but once differential pressure is applied across the tool, both the seal 16 and the lock 20 are self-energised.
It is believed that tools made in accordance with embodiments of the invention, such as the tool 10 described above, will be capable of isolating pressures in excess of 350 bar.
Those of skill in the art will appreciate that the above described tool 10 is merely exemplary of the present invention, and that various modifications and improvements may be made thereto without departing from the scope of the invention. For example, many of the advantages of the invention may be achieved in a tool in which a seal is mounted externally on a pipe, and a lock is provided internally.
Those of skill in the art will recognise that the above described pipe end sealing tool 10 provides a quick and reliable method of temporarily capping open pipes and tubes. The relative locations of the seal 16 and lock 20 allow the tool 10 to be relatively compact, typically half the length of a conventional mechanical plug or mechanical cap. Furthermore, the relative locations of the seal 16 and lock 20 allow the internal seal and external locking loads to balance, such that the pipe wall does not experience significant radial stresses. Furthermore, the tool 10 may be actuated quickly and easily using hydraulic fluid, but once differential pressure is applied across the tool, both the seal 16 and the lock 20 are self-energised.
It is believed that tools made in accordance with embodiments of the invention, such as the tool 10 described above, will be capable of isolating pressures in excess of 350 bar.
Those of skill in the art will appreciate that the above described tool 10 is merely exemplary of the present invention, and that various modifications and improvements may be made thereto without departing from the scope of the invention. For example, many of the advantages of the invention may be achieved in a tool in which a seal is mounted externally on a pipe, and a lock is provided internally.
Claims (32)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
2. The tool of claim 1, wherein the seal comprises a compression seal.
3. The tool of claim 2, wherein the tool is configured such that radial movement of a sealing surface of the seal and a sealing pressure is produced by axial compression of the seal.
4. The tool of claim 1, 2 or 3, wherein the seal comprises an elastomeric seal element.
5. The tool of any one of claims 1 to 4, wherein an annular seal element is provided on a core between opposing compression faces, the faces being relatively movable to compress the element and induce radial expansion of the element.
6. The tool of any one of claims 1 to 5, wherein the seal is adapted to be self-energised.
7. The tool of claim 6, wherein once a minimum pressure differential is achieved across the seal, the tool is configured such that internal pipe pressure tends to maintain the seal in the energised configuration.
8. The tool of any one of claims 1 to 7, wherein the lock comprises a lock member adapted to be selectively urged into engagement with the wall of the pipe.
9. The tool of claim 8, wherein the lock comprises a taper lock.
10. The tool of claim 8 or 9, wherein the lock member comprises an inclined surface and is operatively associated with a relatively movable cooperating member with a corresponding inclined surface.
11. The tool of claim 8, 9 or 10, wherein the lock member includes a surface configuration for gripping the pipe wall surface.
12. The tool of any one of claims 1 to 11, wherein the lock is adapted to be configured such that an ejection load on the tool serves to increase the grip of the lock on the pipe wall surface.
13. The tool of claim 12, wherein the ejection load path through the tool is arranged to bypass a lock actuation system.
14. The tool of any one of claims 1 to 13, wherein the seal and lock are actuated separately.
15. The tool of any one of claims 1 to 13, wherein the seal and lock are adapted to be actuated by a common actuation arrangement.
16. The tool of any of claims 1 to 15, wherein at least one of the seal and lock is fluid actuated.
17. The tool of any one of claims 1 to 16, wherein the lock is adapted to be actuated prior to actuating the seal.
18. The tool of any one of claims 1 to 17, including a fill/vent port.
19. The tool of claim 18, wherein the port extends through a tool core.
20. The tool of claims 18 or 19, wherein the port is configured to provide a high point vent.
21. The tool of any one of claims 1 to 20, wherein the tool comprises a dual seal, whereby a volume between two seals can be pressurised and monitored to allow the integrity of the seal to be verified before pressurising the pipe.
22. A method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, whereby a radial load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, whereby a radial load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
23. A pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby load applied to the pipe wall by the lock is adapted to support the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
24. A method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, whereby load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, whereby load applied to the pipe wall by the lock supports the opposing sealing pressure, the seal and the lock positioned so that the seal pressure and lock load are substantially balanced such that the pipe wall does not experience significant radial stresses.
25. A pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
26. A method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby load applied to the pipe wall by the lock opposes the sealing pressure.
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby load applied to the pipe wall by the lock opposes the sealing pressure.
27. A pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed, wherein the seal is adapted to be self-energised; and a lock mounted on the body and adapted to engage a wall of the pipe end, whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
28. A method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein the seal is adapted to be self-energised and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
29. A pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, wherein at least one of the seal and the lock is fluid actuated and whereby load applied to the pipe wall by the lock opposes the sealing pressure.
a body;
a seal mounted on the body and adapted to apply a sealing pressure to an inner wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage an outer wall of the pipe end, wherein at least one of the seal and the lock is fluid actuated and whereby load applied to the pipe wall by the lock opposes the sealing pressure.
30. A method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a load applied to the pipe wall by the lock opposes the sealing pressure.
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the seal within a pipe end and the lock externally of the pipe end;
engaging an outer wall surface of the pipe end with the lock; and applying a sealing pressure to an inner wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a load applied to the pipe wall by the lock opposes the sealing pressure.
31. A pipe end sealing tool comprising:
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
a body;
a seal mounted on the body and adapted to apply a radial sealing pressure to a wall of a pipe end to be sealed; and a lock mounted on the body and adapted to engage a wall of the pipe end, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
32. A method of sealing an end of a pipe, the method comprising:
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
providing a tool comprising a seal and a lock, both mounted on a tool body;
locating the tool on the end of a pipe;
engaging a wall surface of the pipe end with the lock; and applying a radial sealing pressure to a wall surface of the pipe end with the seal, wherein at least one of the seal and the lock is fluid actuated and whereby a radial load applied to the pipe wall by the lock opposes the sealing pressure.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0706261.5 | 2007-03-30 | ||
| GB0706261A GB0706261D0 (en) | 2007-03-30 | 2007-03-30 | Pipe end sealing tool |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2605728A1 CA2605728A1 (en) | 2008-01-10 |
| CA2605728C true CA2605728C (en) | 2010-10-12 |
Family
ID=38050564
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2605728A Active CA2605728C (en) | 2007-03-30 | 2007-07-20 | Pipe end sealing tool |
Country Status (2)
| Country | Link |
|---|---|
| CA (1) | CA2605728C (en) |
| GB (2) | GB0706261D0 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8573655B2 (en) | 2005-10-06 | 2013-11-05 | Car-Ber Investments Inc. | Pipe sealing tool with external clamp |
| US9297716B2 (en) * | 2009-11-30 | 2016-03-29 | Stats (Uk) Limited | Pipe end sealing tool |
| SG182565A1 (en) * | 2010-01-19 | 2012-08-30 | Greene S Energy Group Llc | Hydrostatic pressure testing system and method |
| GB201019784D0 (en) * | 2010-11-23 | 2011-01-05 | Furmanite Internat Ltd | Closure assembly for pipe end |
| DE202016003401U1 (en) * | 2016-05-28 | 2016-06-09 | VIER Voith Industrial Services GmbH | Pressure tester |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4809751A (en) * | 1988-02-29 | 1989-03-07 | United Technologies Corporation | Pressure test cap |
| CA2646946A1 (en) * | 2006-03-23 | 2007-09-27 | Brasscraft Manufacturing Company | Plumbing test cap with pivotal latch |
-
2007
- 2007-03-30 GB GB0706261A patent/GB0706261D0/en active Pending
- 2007-07-20 CA CA2605728A patent/CA2605728C/en active Active
-
2008
- 2008-03-13 GB GB0804638A patent/GB2448036B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| GB2448036B (en) | 2009-10-21 |
| CA2605728A1 (en) | 2008-01-10 |
| GB0706261D0 (en) | 2007-05-09 |
| GB2448036A (en) | 2008-10-01 |
| GB0804638D0 (en) | 2008-04-16 |
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