Abstract:
A repair apparatus and method is utilized for repairing leaks, ruptures or weaknesses in ell pipe fittings. An arcuate reinforcement structure conforms to the radius of curvature of the convex side of the fitting and a second arcuate reinforcement structure conforms to the curvature of the concave side of the fitting. One or both of the reinforcement structures urges a sealing member against the fitting, with at least one of the sealing members sealing over the leak, rupture, or weakness. The reinforcement structures may have integral bands which may attach to encircle the fitting.

Description:
BACKGROUND OF THE INVENTION 
     The disclosed device relates generally to piping systems and making repairs to the same when the piping system requires either patching of a leak or reinforcement of a leaking section. There are tens of thousands of miles of pipelines utilized by a variety of industries for transporting fluids. Because of age and service which may involve transport of abrasive and/or fluids, the inner walls of these pipelines are subject to continual wear. When these lines fail, there is a loss of product, potential environmental damage, and potentially property damage and/or personal injury. 
     In cases where it is either impractical, inconvenient, or uneconomic to replace the entire pipeline, or the failed section, the leak may be repaired with a pipe patch, which is typically a metal jacket with a rubber gasket which is wrapped around a straight section of pipe and compressed until it stops the product leak until a more permanent solution can be performed such as replacing the leaking section of pipe. However, this type of device is generally only available for relatively straight sections of pipe. There are no comparable devices, which are relatively easy to install and relatively inexpensive, which may be rapidly installed to stop leaks in angled pipe sections, such as pipe 45 and 90 degree elbows (also referred to herein as “ell fittings” or “ells”). That is unfortunate because these types of fittings often experience greater internal wear than straight sections of pipe, particularly on the outward side of the elbow (i.e., on the convex side) where erosional damage and turbulence may be at a maximum because this surface undergoes the greatest of the change in flow direction of the fluid flowing in the line. Once the wear is significant enough, liquid will begin to leak through the pipe wall from the inside to the outside beginning with a dripping pinhole, then escalating to a larger hole leaking the fluids transported within the pipeline into the environment. The release of the material itself may be problematic. For example, if the material is oil, the release can be harmful to the environment and/or to personnel. Some fluids may be hot or toxic, and it almost always desirable to contain the leak as quickly as possible. 
     Given the nature of the fluid and the services, a pipeline leak can have severe consequences. When these leaks occur within elbows, under the known procedures, it is usually necessary to shut the pipeline down, which can result in plant shutdowns, lost product, delayed deliveries and expensive repairs. For example, various hot-tapping procedures require isolating the leaking pipe segment, thus requiring a system shut-down. 
     It should be further noted that failures on the inside bend of ell fittings is not uncommon, comprising 5 to 10 percent of ell failures. The availability of effective, fast, and easily installed repair solutions to failures of the inside bend is desirable. It would be desirable to have a fast and relatively inexpensive means of repairing leaks in elbows, where the repair apparatus is reliable and capable of providing service for a relatively extended period of time if necessary. It would also be desirable to have a repair apparatus which can be installed by a single individual without the need for welding apparatus or other specialized equipment. 
     SUMMARY OF THE INVENTION 
     Embodiments of the presently disclosed apparatus and method answers the need identified above. The present invention allows for a single person to almost immediately stop the leaking of product from a worn angle pipe by compressing a seal gasket and an arcuate reinforcement member against the wall of the leaking pipe fixture. Embodiments of the apparatus and method may be utilized on virtually all commonly used pipe sizes, ranging from 1 inch pipe to the largest possible pipe such as 60 inches in diameter. 
     An embodiment of the apparatus comprises an arcuate reinforcement member having a curvature which corresponds to the curvature of the elbow, which may range from 22.5 degrees to 90 degrees, and in some applications (i.e., “U” fittings), up to 180 degrees. The arcuate reinforcement member is urged against the exterior surface of the elbow, compressing a sealing member against the elbow surface, where the sealing member generally has a shape corresponding to the shape of the arcuate reinforcement member. The sealing member may be fabricated from materials which are resistant to breakdown by oil, condensate, or other fluids flowing through the piping system. 
     An embodiment of the apparatus may further comprise an opposite facing arcuate reinforcement member which will generally be urged against the inside radius of the fitting (i.e., the concave side), where the opposite facing arcuate reinforcement member also urges a sealing member against the exterior surface of the inside radius of the fitting, where the sealing member has a shape generally corresponding to the shape of the arcuate reinforcement member. The reinforcement members are hereinafter referred to as the outside reinforcement member, referring to a reinforcement member which is urged against the outside radius of the fitting, and the inside reinforcement member, corresponding to a reinforcement member which is urged against the inside radius of the fitting. When utilized together, the outside reinforcement member and the inside reinforcement member encircle the girth of the fitting to be repaired each urging its respective sealing member against the exterior surface of the fitting, the reinforcement members each reinforcing one another, and further supporting the fitting. 
     In one embodiment of the apparatus, the outside reinforcement member and the inside reinforcement members are each integral to a band, wherein the bands may be connected together to encircle the fitting. Each band may comprise a fastener retaining structure (referred to herein as a “fastener retaining block”) on each side of the arcuate reinforcement member, each fastener retaining block comprising an aperture for receiving a fastener. When installed on a fitting, a fastener retaining block of one band is in facing relation with a corresponding fastener retaining block of the other band, with the apertures of each fastener retaining block in general alignment, allowing the outside reinforcement member and the inside reinforcement member to be attached to the fitting by the insertion of fasteners within the apertures of the fastener retaining blocks. 
     When the reinforcement members are thus attached together, an enclosing structure is defined which fits around the pipe fitting. An aperture of at least one of the fastener retainer blocks may comprise a slot which extends through the side of the retainer block, thus allowing a fastener to be located within the aperture by pivoting of the fastener through the slot into the aperture. This feature allows the opposing reinforcement members, held together by a single fastener on one side, to be installed on a fitting as a single unit, and then secured by pivoting the second fastener through the slot. This feature allows the apparatus to be quickly installed by a single person, and allows the apparatus to be installed without removing nuts from either fastener. 
     Alternatively, the apparatus may comprise a hinge on one side which attaches the outside reinforcement member and the inside reinforcement members, while the opposite side comprises a latch mechanism which may comprise a hook member which is pivotally attached to an end of a reinforcement member while the opposite facing reinforcement member comprises a keeper, which catches a portion of the hook member. Thus, when the hook member engages the keeper, the outer reinforcement member and the inside reinforcement members enclose the fitting, each reinforcement member urging its integral sealing member against the exterior surface of the fitting. The operative length of the hook member may be adjustable such that the tension placed on the reinforcement members can be adjusted as desired, to provide a tighter seal, or to make the latch mechanism easier to close. For example, the hook member may comprise a bolt having a head which engages the keeper. The opposite end of the bolt may be retained by a pivot member attached to the fastener retainer block of the opposite reinforcement member, where the bolt may be either screwed into the fastener retainer block to shorten the length of the hook member, or the bolt may be backed out of the fastener retainer block to increase its length. Alternatively, the latch mechanism may employ an over-center action to apply sufficient closing force to the reinforcement members. 
     The inside reinforcement member provides for substantial reinforcement of the outside reinforcement member, and allow the urging of the respective sealing members against the exterior surface of the fitting without the reinforcement members actually making contact with the fitting. One benefit of this configuration is that if the reinforcement members are metallic, corrosion problems which might arise from dissimilar metals between the reinforcement members and the fitting will be limited by the absence of surface contact between the fitting and the reinforcement members. The sealing members which may be utilized with embodiments of the invention not only facilitate obtaining a leak-tight seal, but also provide insulation between the material of the reinforcement members and the pipe fitting, thus again avoiding a corrosion cell generated by the use of dissimilar metals. Of course, depending upon the application, the reinforcement members may be manufactured from non-metallic materials, such as carbon fiber composites, fiber glass or other materials appropriate for the application. 
     It should be noted that actual fitting sizes may vary within a nominal size due to differences in production techniques utilized at different manufacturing facilities. However, because embodiments of the present device utilize reinforcement members having a shape which does not individually enclose the entire girth of the fitting, the present apparatus may be utilized for fittings which are not precisely the same size. This adaptability is further enhanced by the utilization of the sealing member and the positive closing force applied by the fasteners on each side of the apparatus or latch mechanism, such that a precise fit is not required to obtain a repair of the pipe fitting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a perspective view of an embodiment of the presently disclosing apparatus. 
         FIG. 2  shows a second perspective view of the embodiment shown in  FIG. 1 . 
         FIG. 3  shows another perspective view of the embodiment of the apparatus shown in  FIG. 1 . 
         FIG. 4  shows a front/back view of an embodiment of the disclosed device. 
         FIG. 5  shows a perspective view of an embodiment of the disclosed device in an “open” position, prior to installation on a pipe fitting. 
         FIG. 6  shows a front/back view of an embodiment of the disclosed device in an open position, prior to installation on a pipe fitting. 
         FIG. 7  shows a perspective view of an embodiment of the disclosed device attached to a pipe fitting. 
         FIG. 8  shows a side view of an embodiment of the disclosed device attached to a pipe fitting. 
         FIG. 9  shows a front/back view of an embodiment of the disclosed device attached to a pipe fitting. 
         FIG. 10  shows a top/bottom view of an embodiment of the disclosed device attached to a pipe fitting. 
         FIG. 11  is a close up view of the inside reinforcement member attached to a pipe fitting. 
         FIG. 12  shows a perspective view of another embodiment of the disclosed device. 
         FIG. 13  shows a side view of the embodiment shown in  FIG. 12 . 
         FIG. 14  shows a perspective view of the embodiment shown in  FIG. 12  with one fastener removed to facilitate installation of the device on a pipe fitting. 
         FIG. 15  shows a perspective view of the embodiment of  FIG. 12  attached to a pipe fitting. 
         FIG. 16  shows a second perspective view of the embodiment of  FIG. 12  attached to a pipe fitting. 
         FIG. 17  shows a side view of the embodiment of  FIG. 12  attached to a pipe fitting. 
         FIG. 18  shows a sectioned view along line A-A from  FIG. 17 . 
         FIG. 19  shows a sectioned view along line B-B from  FIG. 18 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring now to the figures,  FIGS. 1 through 4  show an embodiment of the apparatus  10  in a closed position without being installed on an elbow fitting  100 . This embodiment of the apparatus comprises an arcuate outside reinforcement member  12  having a radius R 1  which is based upon the pipe&#39;s diameter. The arcuate reinforcement member also has a radius R 2  which is defined by the curvature or amount of bend in the fitting as it changes direction. Standard pipe elbows are available as 90 degrees and 45 degrees, with available ranges of 22.5 degrees to 90 degrees. For a long radius elbow, radius R 2  will typically be 1.5× diameter centerline radius. 
     The outside reinforcement member  12  is urged against the exterior surface of the elbow  100 , compressing a sealing member  14  against the outside convex surface of the elbow  100 , where the outside reinforcement member  12  and sealing member  14  generally have a shape corresponding to the shape of the outside surface of the fitting  100 . In other words, as illustrated in  FIG. 10 , the reinforcement member has a width W which fits circumferentially about the fitting, and a length L which fits along a portion of the length of the fitting. A short radius R 1  is defined along the first width corresponding to the radius of curvature of fitting circumference. A long radius R 2  is defined along the first length of the outside reinforcement member  12  corresponding to the radius of curvature along the length of the ell fitting.  FIG. 18 , while showing a different embodiment  110 ′ of the invention, best shows the relationship of the radius of the reinforcement members  112 ,  116  and the corresponding sealing members  114 ,  118  with the radius of the pipe diameter.  FIG. 19 , also showing embodiment  110 ′, best shows the relationship of the sealing members  114 ,  118  with the radius defined along the longitudinal axis of the fitting  100 ′. The reinforcement members  12 ,  16  and sealing members  14 ,  18  of embodiment  10  have a similar relationship with fitting  100 . 
     An embodiment of the apparatus  10  may further comprise an opposite facing arcuate inside reinforcement member  16  which will generally be urged against the inside concave side  102  of the fitting, where the concave side is defined by a radius R 3  The inside reinforcement member  16  urges a sealing member  18  against the exterior surface of the inside radius of the fitting, where the sealing member has radii of curvature R 1  and R 3  and a shape generally corresponding to the shape of the arcuate reinforcement member  16 . Each of the sealing members  14 ,  18  may have a textured or gridded surface to provide for enhanced sealing effectiveness. 
     As suggested by the figures, the inside reinforcement member  16  may be smaller in length than the outside reinforcement member  12 , where the “length” L of each reinforcement member  12 ,  16  is considered to be parallel to the long axis of the fitting  100 , as indicated in  FIG. 10 . The inside reinforcement member  16  may have a shorter length L than the outside reinforcement member  12  to allow for the placement of the inside reinforcement member  16  against the concave portion  102  of the fitting  100 . The inside reinforcement member  16  have the same length L as band  22 . As shown in  FIGS. 7-9 , when utilized together, the outside reinforcement member  12  and the inside reinforcement member  16  and the respect bands  20 ,  22  and bolts  40 ,  42  may encircle the girth of the fitting  100  to be repaired, with each reinforcement member  12 ,  16  urging its respective sealing member  14 ,  18  against the exterior surface of the fitting  100 . In this configuration, the reinforcement members  12 ,  16  each reinforce one another, and further supporting the fitting  100 . 
     In one embodiment of the apparatus  10 , outside reinforcement member  12  is attached to band  20 . Likewise, inside reinforcement member  16  is attached to band  22 . The reinforcement members  12 ,  16  may be separately attached to the respective bands  20 ,  22  by welding, rivets, or other fastener types. Alternatively, the reinforcement members  12 ,  16  may be integral to the bands  20 ,  22 . The apparatus  10  comprises closing means for closing the two bands  20 ,  22  to encircle the fitting  100 . Such closing means may include the use of bolts  40 ,  42 . Alternatively, the closing means may include the use of latches and corresponding keepers at the ends of bands  20 ,  22 . Alternatively, the closing means may include a hinge connecting adjacent ends of bands  20 ,  22 , while the opposite ends of the bands comprise a latch and keeper. The closing means may comprise other means which attach the bands  20 ,  22  to one another such that the associated reinforcement members  12 ,  16  are disposed about a portion of the girth of the fitting  100 . 
     Band  20  may comprise one or more fastener retaining structures, i.e., fastener retaining blocks  24 ,  26  on each end of the band, such that the fastener retaining blocks are on either side of the outside reinforcement member  12 . It is to be noted that the term “fastener retaining block,” as used herein, refers to any attached or integral structure on the bands  20 ,  22  which may be utilized to attach a fastener which connects the two bands, and does not necessarily require a “block” structure. 
     Likewise, band  22  may comprise a fastener retaining block  28 ,  30  on each side of the band, such that the fastener retaining blocks are on either side of the inside reinforcement member  16 . As shown in the figures, the fastener retaining blocks may each be a triangular shaped structure which is formed by the ends of the bands  24 ,  26 . 
     The fastener retaining blocks  24 ,  26 ,  28 ,  30  may each comprise an aperture  32 ,  34 ,  36 ,  38  for receiving a fastener  40 ,  42 , where the appertures  32 ,  34 ,  36 ,  38  extend through two of the legs of the triangular shaped structure of the fastener retaining blocks. At least one of the apertures  36  may comprise a slot  44  which extends through fastener retaining block  28 , thereby allowing fastener  40  to be laterally pivoted into position. Apertures  32 ,  34 ,  36 ,  38  may be have an elliptical cross-section which allows for lateral movement of the fasteners  40 ,  42  within the apertures to facilitate installation of the apparatus  10 . Fasteners  40 ,  42  are typically threaded and may be secured on one end with nuts  46  and may have a pan head  48 ,  50 . These features allow opposing reinforcement member band combinations to be held together by a single fastener  42  on one side and installed on a fitting as a single unit as opposed to two separate pieces. The assembly may then be secured by pivoting the second fastener  40  through the slot  44 . This feature allows the apparatus to be quickly installed by a single person, and allows the apparatus to be installed without removing nuts from either fastener. 
     As an example of installing the apparatus on a fitting  100 , in preparation a fastener retaining block  26  of one band  20  may be placed in facing relation with a corresponding fastener retaining block  30  of the other band  22 , with the apertures  34 ,  38  of each fastener retaining block in general alignment by the insertion of fastener  42  within the apertures  34 ,  38 . In this configuration, as illustrated in  FIGS. 5-6 , without the nut  48  being overly tightened and thus allowing relative movement between the respective bands  20 ,  22 , the device  10  may be placed around fitting  100  by separating fastener blocks  24 ,  28  and slipping the apparatus around the fitting. Once the device  10  is placed around the fitting  100 , fastener  42  may be pivoted into place, with pan head  48  being sufficiently large to prevent fastener  40  from pulling through slot  44 . Once nuts  46 ,  48  are tightened to the correct torque, the apparatus  10  is securely attached to the fitting  100 . This installation method allows a single person to attach the apparatus  10  to a fitting  100 . 
     When the bands  20 ,  22  are thus attached together with fasteners  40 ,  42 , an enclosing structure is defined which fits around the pipe fitting  100 . It is to be appreciated that while the figures depict the pipe fitting  100  in isolation, actual installation of the disclosed apparatus occurs when the fitting is part of a pipeline, in which the pipe fitting  100  may be oriented in any position. The above described installation method nevertheless allows a single person to install the apparatus on the fitting  100 , because the device can be held with one hand and fastener  40  pivoted into place with the second hand. 
       FIGS. 12-19  show another embodiment  110  of the present invention which utilizes a different mechanism for attaching the device to a fitting  100 ′. This embodiment is particularly adapted for smaller sizes of pipe fittings, such as 2 inch diameter fittings, which provide a limited amount of space for attaching the inside reinforcement member  116  within the concave portion of fitting  100 ′. This embodiment does not use a separate band and plate design. In this embodiment outside reinforcement member  112  compresses sealing member  114  against a portion of the outside convex surface of the elbow  100 ′, where the outside reinforcement member  112  and sealing member  114  generally have a shape corresponding to the shape of the outside surface of the fitting  100 ′. Likewise, inside reinforcement member  116  urges sealing member  118  against the a portion of the outside concave surface of the elbow  100 ′. As shown in  FIGS. 15-19 , when utilized together, the outside reinforcement member  112  and the inside reinforcement member  116  and the respective bolts  140 ,  142  encircle the girth of the fitting  100 ′ to be repaired, with each reinforcement member  112 ,  116  urging its respective sealing member  114 ,  118  against the exterior surface of the fitting  100 ′, with nuts  148  securing bolts  140 ,  142  to the respective reinforcement members. In this configuration, the reinforcement members  112 ,  116  each reinforce one another, and further supporting the fitting  100 ′. 
     While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the spirit and scope of the present invention. Thus the scope of the invention should not be limited according to these factors, but according to the following appended claims.