CA1078306A - Method and apparatus for sealing a pipeline leak - Google Patents
Method and apparatus for sealing a pipeline leakInfo
- Publication number
- CA1078306A CA1078306A CA293,033A CA293033A CA1078306A CA 1078306 A CA1078306 A CA 1078306A CA 293033 A CA293033 A CA 293033A CA 1078306 A CA1078306 A CA 1078306A
- Authority
- CA
- Canada
- Prior art keywords
- wire
- gap
- sealant
- flange
- cable
- 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.)
- Expired
Links
- 238000000034 method Methods 0.000 title claims abstract description 25
- 238000007789 sealing Methods 0.000 title claims abstract description 11
- 238000002347 injection Methods 0.000 claims abstract description 62
- 239000007924 injection Substances 0.000 claims abstract description 62
- 239000000565 sealant Substances 0.000 claims abstract description 49
- 238000010618 wire wrap Methods 0.000 claims abstract description 24
- 229940090044 injection Drugs 0.000 claims description 61
- 230000000063 preceeding effect Effects 0.000 claims description 9
- 239000003566 sealing material Substances 0.000 claims description 3
- 238000013022 venting Methods 0.000 claims description 2
- 230000008439 repair process Effects 0.000 abstract description 8
- 208000036366 Sensation of pressure Diseases 0.000 abstract description 2
- 238000009434 installation Methods 0.000 description 4
- 239000000543 intermediate Substances 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 210000002268 wool Anatomy 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000792 Monel Inorganic materials 0.000 description 1
- 101100365516 Mus musculus Psat1 gene Proteins 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 206010043268 Tension Diseases 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 231100000078 corrosiveness Toxicity 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Abstract
METHOD AND APPARATUS FOR SEALING A PIPELINE LEAK
ABSTRACT OF THE DISCLOSURE
In one exemplar embodiment, a method and appara-tus are provided for sealing leaks which occur at the flanged connections of pipelines wherein a wire is wrapped about the upper surface of the flange connecting bolts for filling the gap between the flanges and above the bolts, an injection valve means is installed for relieving pres-sure from inside the gap while the wire is being wrapped and for injecting a sealant to the interior of the gap be-neath the wire wrap, and a sealant is provided for filling the gap beneath the wire wrap for stopping the leak and combining with the wire wrap to provide a permanent repair for the leak.
ABSTRACT OF THE DISCLOSURE
In one exemplar embodiment, a method and appara-tus are provided for sealing leaks which occur at the flanged connections of pipelines wherein a wire is wrapped about the upper surface of the flange connecting bolts for filling the gap between the flanges and above the bolts, an injection valve means is installed for relieving pres-sure from inside the gap while the wire is being wrapped and for injecting a sealant to the interior of the gap be-neath the wire wrap, and a sealant is provided for filling the gap beneath the wire wrap for stopping the leak and combining with the wire wrap to provide a permanent repair for the leak.
Description
, BACKGROUND OF THE INVENTION
This invention relates to methods and apparatus for the repair of leaks at pipeline flanges and more par-ticularly to methods and apparatus for the repair of such leaks in pipelines accomplished without interference with the operation of the pipeline.
The construction of pipelines involves many techniques, but always requires the joining of multiple pieces of pipe. The conventional methods of joining pipe together include such means as welding, threading or the use of flanged ends which are bolted together. Where flanged bolted connections are used, it is not uncommon for leaks to occur in the junction between the two pieces of pipe whereby repairs are required for continued pipe-line operation.
It is obvious that the preferred repair of a pipeline flange leak would be accomplished without the need to disassemble the flanged connection. Since pipe-lines are usually connected to operating systems at either end, it is frequently impractical to shut down the pipe-lines so as to facilitate the repair of the flanged connection.
Various techniques have been developed to attempt to stop such leaks at the flanged connections of pipelines without shutting down the pipeline. One such method uses a cable and a cable tensioning device to close the gap between the flanges and the area to be sealed and hold down wedge-shaped devices adjacent to .. . . . . . . . . .. . . .
10'78306 , ,:
the leaking area. A sealant is then injected into th0 gap between the wedges and the cable 50 that the cable ;
seals and holds the sealant in place while it cures. The cable and tensioning device may then either remain in -place to hold the sealant over the leak or the cable may ~ `
be removed when sufficient friction forces are generated by the wedges to hold the sealant in place. This method seals only a portion of the periphery of the flanged section and is generally unsatisfactory where the seal is subjected to substantial internal pressure.
:
SUMMARY OF THE INVENTION
In a preferred embodiment of the present inven-tion, a method and apparatus are provided to seal leaks in pipeline flange joints while the pipeline remains in operation. The method provides for installing slotted ~-studs in the flange bolt locations so that the slot ex-tends from the gap between the pipe flange faces to the exterior portion of the pipe flange and defines a leak-age relief passage. Injection valve means are installed open to the stud slots to relieve internal pressure which ~-may build up as wire wrapping is put in place. A wire is wrapped to fill the volume of the gap above the flange bolts. Loops of wire are tightly formed and smoothly adjacent to one another to form a plurality of layers.
At about two or three layer intervals, the loops are se-cured by passing the wire under and around the preceding loop. If it is desired, steel wool or some other suitable -flexible sealing material may be placed between inter-mediate layers of the wire wrapping to enhance sealing.
The wrapping is continued until the gap is almost full and a small lip is left between the last layer of wire wrap and the top edge of each of the flanges.
A cable is next positioned within the groove defined by the opposed small lips with a cable tensioning block positioned adjacent the leaking area. The cable is then tensioned by tightening a jack screw of the cable tensioning device. The injection valve opposite the leaking area and the cable tensioning device is then closed, a sealant injection means is connected to the in-jection valve, and a suitable sealant is then injected into the gap area beneath the wire wrap. The cable is repositioned and these steps are repeated at each injection valve location around the periphery of the flange until the leaks are stopped and the sealant flows out around the wire cable. After a short interval of time, sealant is again injected at each injection valve loc~tion to insure complete filling of the gap. The cable is removed and sealant is applied around the periphery of the gap between the flanges until the sealant is level with the edge of the flanges. The injection valves are then removed from the injection nuts and plugs installed in the vacated holes of the valve nuts to complete the installation.
10~!3306 , Further, apparatus is provided whereby the above technique can be accomplished. More particularly, a slotted stud is provided which replaces an original bolt at the flanged connection, the slot length being such that it will provide a communication between the interior of the gap between the flanges and the exterior of one of the flanges. An injection nut is provided to fit the slotted end of the stud with a hole provided in the nut extending from the interior to the exterior so that the nut can be positioned with the hole opening to the slot in the stud. An injection valve then mates with the end of the hole opposite the slot so that a valved entry is provided to the gap between the pipe flanges. A wire is wrapped about the periphery of the flanged connection to fill the area of the gap between the pipe flanges and a-bove the outer surfaces of the flange bolts and to provide the strength necessary to withstand the internal pressures which may be generated as a result of the leaking pipe joint. The injection valve relieve the internal pres-sure while the wire wrap is being installed. A cable anda cable tensioning means are used to provide external pressure on the wire wrap while a sealant is injected be-neath the wire wrap under pressure in order to fill the gap and stop the leaks. An injection means is then used to inject the sealant under pressure into the gap between the flanges and beneath the wire wrap. The sealant is chosen to be compatible with the expected system operating parameters.
It is obvious that flanged connections are used in the construction of many items in addition to pipelines, such as pressuxe vessels and heat exchangers. Therefore the use of the terms pipeline flange and pipe flange is intended and should be construed to be broad enough to encompass bolted flanged connections in general so that application of this invention is not limited to use on pipelines.
It is a feature of the present invention to provide a method and apparatus for sealing a pipeline flange leak~
It is another feature of the present invention to provide a method and apparatus for sealing a pipeline flange leak while the pipeline and related systems remain in operation.
It is yet another feature of the present invention to provide a method and apparatus for providing a permanent seal for a pipeline flange leak capable of withstanding system operating parameters.
It is still another feature of the present inven-tion to provide for a method and apparatus for sealing a pipeflan~e leak which can be performed in the field with ordinary tools and personnel.
In accordance with one aspect of the present inven-tion, there is provided a method for sealing leaks at bolted flanged connections of pipelines comprising replacing at least one of the flange bolts with a valve means opening to a gap between the flange faces, venting the gap through the valve means, wrapping wire over the exposed flange bolts in the gap between the pipeline flange faces so as to form one of more layers of wire in the gap, and injecting a sealant through the i~` valve means to fill the interior of the gap to stop the leak. --In accordance with a further aspect of the present `` 1078306 invention, there is provided a method for sealing leaks at bolted flanged connections of pipelines, comprising installing a plurality of slotted studs with nuts on the end opposite the slot through flange bolt holes, placing an injection nut with an injection valve attached thereto on the slotted end of each slotted stud whereby the injection valve communicates with the slot extending into the gap between the flange faces, wrapping wire around the flange bolts in the gap to form loops in the gap, each loop being formed in tight, smooth proximity to each preceeding loop to form layers of wire across the gap, forming a plurality of wire layers, securing the wire at various inter-mediate layers by passing the wire around the preceeding loop, until the gap is almost filled but leaving a ~ip between the top wire layer and the edge of the flange, placing a cable and cable tensioning means over the wire wrapping in the gap, positioning the cable tensioning means to bear adjacent the leak as the cable is tensioned, injecting a sealant by a sealant injection means attached to the injection valve oppo-site the cable tensioning means, and releasing the reposition-ing the cable with the cable tensioning means~ adjacent eachinjection valve as sealant is injected through each valve unt~il the gap between the flanges is substantially filled with sealant.
BRIEF DESCRIPTI~ OF THE DRAWI~GS
.
In order that the manner in which the above-re-cited advantages and feature of the invention are attained can be understood in detail, a more particular description of the invention may be had by reference to specific em-., -.') t -6a-- . : . : ............................. , ~ .
: . :;. -. ; ", . , :,. : :
-` 11)7830~;
bodiments thereof which are illustrated in the appended drawings, which drawings form a part of this specification. -~
It is to be noted, however, that the appended drawings illustrate only typical embodiments of the invention and therefore are not to be considered limiting of its scope for the invention may admit to further equally effective embodiments.
IN THE DRAWINGS:
Figure 1 is a side view partially in cross-sec-tion showingl the installed injection valves on a leakingpipeline flange.
Figure 2 is a side view showing the wire being wrapped and secured.
Figure 3 is a side view showing the cable and cable tensioning device installed during sealant injection.
Figure 4 is a side view partially in cross-sec-tion of the completed installation.
Figure 1 is a side view of the pipe flange con-nection showing the installed injection valves. More par-ticularly, pipes 10 meet at pipe joint 14 and are held to-gether by a bolted connection formed by inserting bolts 12 through the flanges 13 on each piece of pipe 10 and thread-ing nuts 11 onto the bolts 12 so as to seal pipe joint 14.
If a leak deve~psat pipe joint 14, it is desirable to repair the leak without the need for disassembling the flanged connection. In effecting such a repair, the first ;~
step is the installation of a plurality of injection valve means 20. Injection valve means 20 is used to relieve any :` 107~3V6 internal pressure build up which may occur between pipe flanges 13 during subsequent operations described herebelow.
To install injection valve means 20, a conven-tional bolt 12 is first removed and slotted stud 21 is in-serted through flanges 13. Slot 25 extends from one end of stud 21 a distance sufficient to extend into gap 15 between pipe flanges 13. Nut ll is installed on stud 21 opposite the slotted end and threaded a sufficient distance to bring slot 25 into communication with gap 15. Capped injection nut 20 is threaded onto slotted stud 21 so as to engage flange 13 and align hole 27 through injection nut 22 with slot 25. Nut ll is then tightened to complete the installation. Injection valve means 20 are installed at one or more locations around flange 13. Figure 1 also shows another type of injection valve means 30 including a stud 31 that is formed to define a slot 33 that extends from gap 15 to the exterior of the flange 13 but terminates short of the end of stud 31. Injection nut 32 is in the form of a standard nut and is threaded onto stud 31 a sufficient distance to contact flange 13 and align hole 34 extending through injection nut 32 with slot 33. To complete the in-stallation, injection valve 23 is connected to injection nut 22 or injection nut 32and valve stem 24 is rotated so as to open injection valve 23.
Figure 2 is a side view showing wire wrapping and securing operations. Wire wrap means 40 is provided, ge-nerally consisting of roll 41 and wire 42 wound thereon.
Wire 42 is generally of sufficient strength to withstand the expected system operating conditions and is typically 1~78306 a high tensile strength metal wire. Depending on the application and the internal leak pressures and corrosive-ness of the leaking fluid, steel, stainless steel, copper or monel wire may be used. To begin the wire wrapping operations, one end of wire 42 is first securely tied to bolt 12 in flange gap 15 and wire 42 is looped over the outer surface of flange bolts 12, slotted studs 21 and slotted studs 31 if installed, so as to encircle the 10 flanged connection. Each loop of wire 42 is tightly drawn and arranged to fit smoothly against the preceeding loop until one layer has been installed across gap 15.
Subsequent layers of wire 42 are formed by continued wrapping of wire 42 is smooth, tight loops inside gap 15.
At intermediate points in the wire wrapping operation generally after two or three layers have been formed, the wrapping is secured by passing the roll of wire 41 under and around the preceeding loop. If desired, roll 41 may be ~o ~assed under and around the loop a number 2D of times. The wrapping is secured in this fashion at subsequent points in the operation and it is preferrable to arrange the secured sections at different locations about the periphery of pipe flange gap 15. If desired, a sealing material such as steel wool 43 may be laid between intermediate layers of wire 42 during the wrapping opera- -tions. The wrapping operation continues until pipe flange gap 15 is almost filled. A small lip, generally about -1/8-inch, is left between the top of the last layer of wire 42 and the top of flange 13. Wire 42 is secured by passing roll 41 under and around the last preceeding loop and wire 42 is cut to complete the wrapping operation.
_9_ 10783~6 Figure 3 is a side view showing the cable and cable tensioning device installed during sealant injection.
After the wire wrap is completed, cable tensioning means 50 is installed over the top layer of wire 42 by placing cable 51 around the flanges 13 and adjacent wire 42.
Cable tensioning block 54 is placed adjacent the leaking area and cable 51 is securely clamped to cable claim 52 by tightening nut 53 and the cable 51 is tensioned by tightening jack screw 55 against tensioning block 54.
The sealant injection operation is now begun by closing valve stem 24 of injection valve 23 nearest the area where cable 51 engages flanges 13. Sealant injection means 60 is connected to injection valve 23 and valve stem 24 is rotated to open injection valve 23. Sealant 63 is injected into gap 15 beneath the wire wrap 42, via injection valve 23 until a pressure build up occurs or sealant 63 blows out anywhere around the wire wrap 42 and flanges 13. The ca-ble 51 is left in place long enough for the sealant to ~-set. Valve stem 24 is then rotated to close injection valve 23 and injection means 60 is disconnected from injection valve 23.
; Jack screw 55 is then turned to remove the ten-sion in cable 51 and cable tensioning means 50 is rotated to a position adjacent another injection valve 23. Sea-lant injection means 60 is then connected to the injection valve 23 adjacent the new contact between cable 51 and wire 42 and the process is repeated. Sealant 63 is in-jected to each injection valve 23 in turn until the leaks ,~
'~
: .
' .
---` 1078306 are stopped. Sealant 63 is then injected slowly until sealant 63 flows out around wire 42 or cable 5 The sea-lant 63 is allowed to sit for a short period of time, ap-proximately 10 minutes, and then sealant 63 is again pumped into all injection valves 23.
Figure 4 is a side view of the completed seal.
Cable tensioning means 50 has been removed after the sea-lant 63 has set a sufficient time to cure in place. In-jection valve 23 has been removed from injection nut 22 and injection nut 32 and plugs 26 have been installed to close the holes 27 and 34 respectively. Sealant 63 is applied to fill the lip betwen flanges 12 and wire 42.
Wire 42 generally fills gap 15 above the flange bolts 12 and acts as a strength member to hold sealant 63 is place under the expected system internal pressure. Sealant 63 is placed over the outer layer of wire 42 until flush with the outer periphery of flanges 13 to provide a smooth, ~ -finished appearance for the completed flange seal.
Sealants are selected for the particular appli-20cation. At low pressures, a granular teflon with an injec-tion vehicle, such as oil may be used. Most applications ;i-at higher pressures must use a quick, hard setting sealant commonly having a base of rubber or phenolic. Setting times are common 5 - 15 minutes.
Numerous variations and modifications may ob- ~-viously be made in the structure herein described without departing from the present invention. Accordingly, it should be clearly understood that the forms of the inven-tion herein described and shown in the figures of the accom-panying drawings are illustrative only and are not in-tended to limit the scope of the invention.
.. ..
This invention relates to methods and apparatus for the repair of leaks at pipeline flanges and more par-ticularly to methods and apparatus for the repair of such leaks in pipelines accomplished without interference with the operation of the pipeline.
The construction of pipelines involves many techniques, but always requires the joining of multiple pieces of pipe. The conventional methods of joining pipe together include such means as welding, threading or the use of flanged ends which are bolted together. Where flanged bolted connections are used, it is not uncommon for leaks to occur in the junction between the two pieces of pipe whereby repairs are required for continued pipe-line operation.
It is obvious that the preferred repair of a pipeline flange leak would be accomplished without the need to disassemble the flanged connection. Since pipe-lines are usually connected to operating systems at either end, it is frequently impractical to shut down the pipe-lines so as to facilitate the repair of the flanged connection.
Various techniques have been developed to attempt to stop such leaks at the flanged connections of pipelines without shutting down the pipeline. One such method uses a cable and a cable tensioning device to close the gap between the flanges and the area to be sealed and hold down wedge-shaped devices adjacent to .. . . . . . . . . .. . . .
10'78306 , ,:
the leaking area. A sealant is then injected into th0 gap between the wedges and the cable 50 that the cable ;
seals and holds the sealant in place while it cures. The cable and tensioning device may then either remain in -place to hold the sealant over the leak or the cable may ~ `
be removed when sufficient friction forces are generated by the wedges to hold the sealant in place. This method seals only a portion of the periphery of the flanged section and is generally unsatisfactory where the seal is subjected to substantial internal pressure.
:
SUMMARY OF THE INVENTION
In a preferred embodiment of the present inven-tion, a method and apparatus are provided to seal leaks in pipeline flange joints while the pipeline remains in operation. The method provides for installing slotted ~-studs in the flange bolt locations so that the slot ex-tends from the gap between the pipe flange faces to the exterior portion of the pipe flange and defines a leak-age relief passage. Injection valve means are installed open to the stud slots to relieve internal pressure which ~-may build up as wire wrapping is put in place. A wire is wrapped to fill the volume of the gap above the flange bolts. Loops of wire are tightly formed and smoothly adjacent to one another to form a plurality of layers.
At about two or three layer intervals, the loops are se-cured by passing the wire under and around the preceding loop. If it is desired, steel wool or some other suitable -flexible sealing material may be placed between inter-mediate layers of the wire wrapping to enhance sealing.
The wrapping is continued until the gap is almost full and a small lip is left between the last layer of wire wrap and the top edge of each of the flanges.
A cable is next positioned within the groove defined by the opposed small lips with a cable tensioning block positioned adjacent the leaking area. The cable is then tensioned by tightening a jack screw of the cable tensioning device. The injection valve opposite the leaking area and the cable tensioning device is then closed, a sealant injection means is connected to the in-jection valve, and a suitable sealant is then injected into the gap area beneath the wire wrap. The cable is repositioned and these steps are repeated at each injection valve location around the periphery of the flange until the leaks are stopped and the sealant flows out around the wire cable. After a short interval of time, sealant is again injected at each injection valve loc~tion to insure complete filling of the gap. The cable is removed and sealant is applied around the periphery of the gap between the flanges until the sealant is level with the edge of the flanges. The injection valves are then removed from the injection nuts and plugs installed in the vacated holes of the valve nuts to complete the installation.
10~!3306 , Further, apparatus is provided whereby the above technique can be accomplished. More particularly, a slotted stud is provided which replaces an original bolt at the flanged connection, the slot length being such that it will provide a communication between the interior of the gap between the flanges and the exterior of one of the flanges. An injection nut is provided to fit the slotted end of the stud with a hole provided in the nut extending from the interior to the exterior so that the nut can be positioned with the hole opening to the slot in the stud. An injection valve then mates with the end of the hole opposite the slot so that a valved entry is provided to the gap between the pipe flanges. A wire is wrapped about the periphery of the flanged connection to fill the area of the gap between the pipe flanges and a-bove the outer surfaces of the flange bolts and to provide the strength necessary to withstand the internal pressures which may be generated as a result of the leaking pipe joint. The injection valve relieve the internal pres-sure while the wire wrap is being installed. A cable anda cable tensioning means are used to provide external pressure on the wire wrap while a sealant is injected be-neath the wire wrap under pressure in order to fill the gap and stop the leaks. An injection means is then used to inject the sealant under pressure into the gap between the flanges and beneath the wire wrap. The sealant is chosen to be compatible with the expected system operating parameters.
It is obvious that flanged connections are used in the construction of many items in addition to pipelines, such as pressuxe vessels and heat exchangers. Therefore the use of the terms pipeline flange and pipe flange is intended and should be construed to be broad enough to encompass bolted flanged connections in general so that application of this invention is not limited to use on pipelines.
It is a feature of the present invention to provide a method and apparatus for sealing a pipeline flange leak~
It is another feature of the present invention to provide a method and apparatus for sealing a pipeline flange leak while the pipeline and related systems remain in operation.
It is yet another feature of the present invention to provide a method and apparatus for providing a permanent seal for a pipeline flange leak capable of withstanding system operating parameters.
It is still another feature of the present inven-tion to provide for a method and apparatus for sealing a pipeflan~e leak which can be performed in the field with ordinary tools and personnel.
In accordance with one aspect of the present inven-tion, there is provided a method for sealing leaks at bolted flanged connections of pipelines comprising replacing at least one of the flange bolts with a valve means opening to a gap between the flange faces, venting the gap through the valve means, wrapping wire over the exposed flange bolts in the gap between the pipeline flange faces so as to form one of more layers of wire in the gap, and injecting a sealant through the i~` valve means to fill the interior of the gap to stop the leak. --In accordance with a further aspect of the present `` 1078306 invention, there is provided a method for sealing leaks at bolted flanged connections of pipelines, comprising installing a plurality of slotted studs with nuts on the end opposite the slot through flange bolt holes, placing an injection nut with an injection valve attached thereto on the slotted end of each slotted stud whereby the injection valve communicates with the slot extending into the gap between the flange faces, wrapping wire around the flange bolts in the gap to form loops in the gap, each loop being formed in tight, smooth proximity to each preceeding loop to form layers of wire across the gap, forming a plurality of wire layers, securing the wire at various inter-mediate layers by passing the wire around the preceeding loop, until the gap is almost filled but leaving a ~ip between the top wire layer and the edge of the flange, placing a cable and cable tensioning means over the wire wrapping in the gap, positioning the cable tensioning means to bear adjacent the leak as the cable is tensioned, injecting a sealant by a sealant injection means attached to the injection valve oppo-site the cable tensioning means, and releasing the reposition-ing the cable with the cable tensioning means~ adjacent eachinjection valve as sealant is injected through each valve unt~il the gap between the flanges is substantially filled with sealant.
BRIEF DESCRIPTI~ OF THE DRAWI~GS
.
In order that the manner in which the above-re-cited advantages and feature of the invention are attained can be understood in detail, a more particular description of the invention may be had by reference to specific em-., -.') t -6a-- . : . : ............................. , ~ .
: . :;. -. ; ", . , :,. : :
-` 11)7830~;
bodiments thereof which are illustrated in the appended drawings, which drawings form a part of this specification. -~
It is to be noted, however, that the appended drawings illustrate only typical embodiments of the invention and therefore are not to be considered limiting of its scope for the invention may admit to further equally effective embodiments.
IN THE DRAWINGS:
Figure 1 is a side view partially in cross-sec-tion showingl the installed injection valves on a leakingpipeline flange.
Figure 2 is a side view showing the wire being wrapped and secured.
Figure 3 is a side view showing the cable and cable tensioning device installed during sealant injection.
Figure 4 is a side view partially in cross-sec-tion of the completed installation.
Figure 1 is a side view of the pipe flange con-nection showing the installed injection valves. More par-ticularly, pipes 10 meet at pipe joint 14 and are held to-gether by a bolted connection formed by inserting bolts 12 through the flanges 13 on each piece of pipe 10 and thread-ing nuts 11 onto the bolts 12 so as to seal pipe joint 14.
If a leak deve~psat pipe joint 14, it is desirable to repair the leak without the need for disassembling the flanged connection. In effecting such a repair, the first ;~
step is the installation of a plurality of injection valve means 20. Injection valve means 20 is used to relieve any :` 107~3V6 internal pressure build up which may occur between pipe flanges 13 during subsequent operations described herebelow.
To install injection valve means 20, a conven-tional bolt 12 is first removed and slotted stud 21 is in-serted through flanges 13. Slot 25 extends from one end of stud 21 a distance sufficient to extend into gap 15 between pipe flanges 13. Nut ll is installed on stud 21 opposite the slotted end and threaded a sufficient distance to bring slot 25 into communication with gap 15. Capped injection nut 20 is threaded onto slotted stud 21 so as to engage flange 13 and align hole 27 through injection nut 22 with slot 25. Nut ll is then tightened to complete the installation. Injection valve means 20 are installed at one or more locations around flange 13. Figure 1 also shows another type of injection valve means 30 including a stud 31 that is formed to define a slot 33 that extends from gap 15 to the exterior of the flange 13 but terminates short of the end of stud 31. Injection nut 32 is in the form of a standard nut and is threaded onto stud 31 a sufficient distance to contact flange 13 and align hole 34 extending through injection nut 32 with slot 33. To complete the in-stallation, injection valve 23 is connected to injection nut 22 or injection nut 32and valve stem 24 is rotated so as to open injection valve 23.
Figure 2 is a side view showing wire wrapping and securing operations. Wire wrap means 40 is provided, ge-nerally consisting of roll 41 and wire 42 wound thereon.
Wire 42 is generally of sufficient strength to withstand the expected system operating conditions and is typically 1~78306 a high tensile strength metal wire. Depending on the application and the internal leak pressures and corrosive-ness of the leaking fluid, steel, stainless steel, copper or monel wire may be used. To begin the wire wrapping operations, one end of wire 42 is first securely tied to bolt 12 in flange gap 15 and wire 42 is looped over the outer surface of flange bolts 12, slotted studs 21 and slotted studs 31 if installed, so as to encircle the 10 flanged connection. Each loop of wire 42 is tightly drawn and arranged to fit smoothly against the preceeding loop until one layer has been installed across gap 15.
Subsequent layers of wire 42 are formed by continued wrapping of wire 42 is smooth, tight loops inside gap 15.
At intermediate points in the wire wrapping operation generally after two or three layers have been formed, the wrapping is secured by passing the roll of wire 41 under and around the preceeding loop. If desired, roll 41 may be ~o ~assed under and around the loop a number 2D of times. The wrapping is secured in this fashion at subsequent points in the operation and it is preferrable to arrange the secured sections at different locations about the periphery of pipe flange gap 15. If desired, a sealing material such as steel wool 43 may be laid between intermediate layers of wire 42 during the wrapping opera- -tions. The wrapping operation continues until pipe flange gap 15 is almost filled. A small lip, generally about -1/8-inch, is left between the top of the last layer of wire 42 and the top of flange 13. Wire 42 is secured by passing roll 41 under and around the last preceeding loop and wire 42 is cut to complete the wrapping operation.
_9_ 10783~6 Figure 3 is a side view showing the cable and cable tensioning device installed during sealant injection.
After the wire wrap is completed, cable tensioning means 50 is installed over the top layer of wire 42 by placing cable 51 around the flanges 13 and adjacent wire 42.
Cable tensioning block 54 is placed adjacent the leaking area and cable 51 is securely clamped to cable claim 52 by tightening nut 53 and the cable 51 is tensioned by tightening jack screw 55 against tensioning block 54.
The sealant injection operation is now begun by closing valve stem 24 of injection valve 23 nearest the area where cable 51 engages flanges 13. Sealant injection means 60 is connected to injection valve 23 and valve stem 24 is rotated to open injection valve 23. Sealant 63 is injected into gap 15 beneath the wire wrap 42, via injection valve 23 until a pressure build up occurs or sealant 63 blows out anywhere around the wire wrap 42 and flanges 13. The ca-ble 51 is left in place long enough for the sealant to ~-set. Valve stem 24 is then rotated to close injection valve 23 and injection means 60 is disconnected from injection valve 23.
; Jack screw 55 is then turned to remove the ten-sion in cable 51 and cable tensioning means 50 is rotated to a position adjacent another injection valve 23. Sea-lant injection means 60 is then connected to the injection valve 23 adjacent the new contact between cable 51 and wire 42 and the process is repeated. Sealant 63 is in-jected to each injection valve 23 in turn until the leaks ,~
'~
: .
' .
---` 1078306 are stopped. Sealant 63 is then injected slowly until sealant 63 flows out around wire 42 or cable 5 The sea-lant 63 is allowed to sit for a short period of time, ap-proximately 10 minutes, and then sealant 63 is again pumped into all injection valves 23.
Figure 4 is a side view of the completed seal.
Cable tensioning means 50 has been removed after the sea-lant 63 has set a sufficient time to cure in place. In-jection valve 23 has been removed from injection nut 22 and injection nut 32 and plugs 26 have been installed to close the holes 27 and 34 respectively. Sealant 63 is applied to fill the lip betwen flanges 12 and wire 42.
Wire 42 generally fills gap 15 above the flange bolts 12 and acts as a strength member to hold sealant 63 is place under the expected system internal pressure. Sealant 63 is placed over the outer layer of wire 42 until flush with the outer periphery of flanges 13 to provide a smooth, ~ -finished appearance for the completed flange seal.
Sealants are selected for the particular appli-20cation. At low pressures, a granular teflon with an injec-tion vehicle, such as oil may be used. Most applications ;i-at higher pressures must use a quick, hard setting sealant commonly having a base of rubber or phenolic. Setting times are common 5 - 15 minutes.
Numerous variations and modifications may ob- ~-viously be made in the structure herein described without departing from the present invention. Accordingly, it should be clearly understood that the forms of the inven-tion herein described and shown in the figures of the accom-panying drawings are illustrative only and are not in-tended to limit the scope of the invention.
.. ..
Claims (6)
1. A method for sealing leaks at bolted flanged connections of pipelines comprising replacing at least one of the flange bolts with a valve means opening to a gap between the flange faces, venting the gap through the valve means, wrapping wire over the exposed flange bolts in the gap between the pipeline flange faces so as to form one of more layers of wire in the gap, and injecting a sealant through the valve means to fill the interior of the gap to stop the leak.
2. The method of Claim 1 whereby the step of replacing one or more of the bolts with valve means fur-ther comprises removing at least one bolt from the flange, installing a slotted stud with a nut on the end opposite the slot, placing an injection nut on the slotted end of the stud with an opening therein to the slot, and installing an injection valve on each injection nut so as to relievepressure from the gap between the flanges.
3. The method of Claim 1 whereby the step of wrapping a wire over the flange bolts further comprises securing one end of the wire to one of the flange bolts, and looping the wire around all the bolts in the gap, forming each loop in tight, smooth proximity to each preceeding loop to form one or more layers of wire across the gap, securing the wire after forming a plurality of said layers by passing the wire around the next preceeding loop, and forming said layers of wire and securing the wire after a plurality of layers until the gap is almost filled but leaving a lip between the top wire layer and the edge of the flange.
4. The method of Claim 3 further comprising adding an intermediate layer of sealing material after completing a portion of the layers of wire wrapping.
5. The method of Claim 1 whereby the step of injecting a sealant further comprises placing a cable and cable tensioning means over the wire wrapping in the gap so that the cable tensioning means is positioned to bear around the area of the leak, tensioning the cable by the cable tensioning means about the wire wrapping opposite the leak, attaching a sealant injection means to the in-jection valve means opposite the leak, injecting a sealant through the valve means into the gap, repositioning the cable tensioning means adja-cent another injection valve means and repeating the steps of injecting sealant and repositioning the cable tensioning means until the leak has stopped, and continuing to slowly inject sealant until the gap under the wire wrapping is substan-tially filled.
6. A method for sealing leaks at bolted flanged connections of pipelines, comprising installing a plurality of slotted studs with nuts on the end opposite the slot through flange bolt holes, placing an injection nut with an injection valve attached thereto on the slotted end of each slotted stud whereby the injection valve communicates with the slot extending into the gap between the flange faces, wrapping wire around the flange bolts in the gap to form loops in the gap, each loop being formed in tight, smooth proximity to each preceeding loop to form layers of wire a-cross the gap, forming a plurality of wire layers, securing the wire at various intermediate layers by passing the wire around the preceeding loop, until the gap is almost filled but leaving a lip between the top wire layer and the edge of the flange, placing a cable and cable tensioning means over the wire wrapping in the gap, positioning the cable tensioning means to bear adjacent the leak as the cable is tensioned, injecting a sealant by a sealant injection means attached to the injection valve opposite the cable tensioning means, and releasing and repositioning the cable with the cable tensioning means adjacent each injec-tion valve as sealant is injected through each valve until the gap between the flanges is substantially filled with sealant.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA293,033A CA1078306A (en) | 1977-12-14 | 1977-12-14 | Method and apparatus for sealing a pipeline leak |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA293,033A CA1078306A (en) | 1977-12-14 | 1977-12-14 | Method and apparatus for sealing a pipeline leak |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1078306A true CA1078306A (en) | 1980-05-27 |
Family
ID=4110281
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA293,033A Expired CA1078306A (en) | 1977-12-14 | 1977-12-14 | Method and apparatus for sealing a pipeline leak |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1078306A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113811060A (en) * | 2021-09-14 | 2021-12-17 | 广气(广州)能源科技有限公司 | Pipeline static conduction bridging mode and structure |
-
1977
- 1977-12-14 CA CA293,033A patent/CA1078306A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113811060A (en) * | 2021-09-14 | 2021-12-17 | 广气(广州)能源科技有限公司 | Pipeline static conduction bridging mode and structure |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4073836A (en) | Method and apparatus for sealing a pipeline leak | |
| US3467141A (en) | Flange coupling repair ring | |
| US4756338A (en) | Pipe repair assemblies to repair pipe when fluids therein are under high pressure | |
| RU2372548C2 (en) | Method to eliminate gas leaks in pipeline flange zone | |
| WO2018000534A1 (en) | Method of pipe leakage repairing device | |
| US6217688B1 (en) | Method of repairing a flanged pipe joint | |
| US6884373B1 (en) | Process for securing a branch assembly to a pipeline | |
| GB2027513A (en) | Method and apparatus for sealing a pipeline leak | |
| WO2018000536A1 (en) | Pipe leakage repairing device | |
| US6990718B2 (en) | Tee connection to a pipeline | |
| AU2002321600A1 (en) | Tee connection to a pipeline | |
| US6612341B2 (en) | Securing shell assemblies to pipelines | |
| CA1078306A (en) | Method and apparatus for sealing a pipeline leak | |
| KR100749550B1 (en) | Method for mending of water leakage interception in water main and structure the same | |
| RU2314453C1 (en) | Method to repair defective section of operating pipeline | |
| CA1076980A (en) | Method and apparatus for sealing a pipeline leak | |
| JP4092751B2 (en) | Flange face sealing method and apparatus for flange joints of piping | |
| AU2001250504A1 (en) | Securing shell assemblies to pipelines | |
| RU2292512C1 (en) | Method of repairing rectilinear section of pipeline | |
| CN205978429U (en) | Shovel tight type flange anchor clamps | |
| KR200427040Y1 (en) | Mending structure of water leakage interception in water main | |
| IL147625A (en) | Tee connection to a pipeline | |
| GB2182745A (en) | Improvements relating to methods for sealing joints | |
| JPH01111199A (en) | Repair of leakage in tube type heat exchanger | |
| WO2000057099A1 (en) | Apparatus and method for repairing a leak |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |