Abstract:
A pipe stub is provided that includes an elongated cylindrical portion that is selectively sealed on one end. For example, the cylindrical portion may be selectively sealed with a removable diaphragm. In operation, after the pipe stub is interconnected to a plumbing system and a leak test is completed, the plumber severs show otherwise circumvents the diaphragm to open the pipe stub, which can be used to receive additional plumbing components.

Description:
[0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/722,756, filed Nov. 5, 2012, the entire disclosure of which is incorporated by reference herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    Embodiments of the present invention are generally related to pipe stubs that are used to selectively seal portions of a plumbing system being tested. 
       BACKGROUND OF THE INVENTION 
       [0003]    Plumbing systems of new or existing buildings are commonly leak tested. Further, those of skill in the art appreciate that the plumbing system of a new building is tested numerous times during construction. For example, after basement plumbing is “roughed in” and before a concrete floor is poured, all openings in the plumbing system are sealed or otherwise blocked. Next, that portion of the plumbing system is filled with water and a hydrostatic pressure test is performed wherein the pipes are pressurized about 5 to 15 psi. The tested portion is inspected to identify any leaks. After the basement test is complete, the other floors of the building are tested in the same manner. When all tests are complete, the plumbing system is finished by interconnecting sinks, bathtubs, etc., to the various openings of the plumbing system that were blocked during the test. 
         [0004]    Currently, caps or plugs are used to block or seal all but one of the openings in the plumbing system or a segment thereof. In operation, the plugs are inserted into the pipe, the plumbing system is tested, and the plugs are removed so that the plumbing system can be finished. One common test plug is comprised of an expandable elastomeric material that is positioned between two metallic members that when compressed expands to engage an inner surface of the pipe to seal the same.  FIGS. 1-3  show a plug  2  of the prior art that is comprised of a first plate  6  separated from a second plate  10  by an elastomeric member  14 . A bolt  18  spans between the first plate  6  and the second plate  10  wherein one end of the bolt  18  is secured to the first plate  6 . A nut  22 , which may be spaced from the second plate  10  with a washer  26 , is also interconnected to the bolt  18 . In operation, as the nut  22  is tightened, the first plate  6  is drawn towards the second plate  10  which compresses the elastomeric member  14  longitudinally and expands it laterally as shown in  FIG. 2 . In the expanded state, the edge of the elastomeric member  14  will firmly engage the inner surface  30  of a pipe stub  34  that has been interconnected via adhesive to an opening, i.e., a tee connector  38 , of the plumbing system. The plug  2  is removed by loosening the nut  22  which relaxes the elastomeric member  14 . 
         [0005]    One disadvantage using a plug is that it can be difficult to position and align within the pipe stub, which could cause a loss in pressure during the test which could be mistaken as a leak. Further, it is difficult and some instances to insert tools into the stub to tighten the nut or other mechanism that biases the first plate towards second plate. The greatest drawback is that plugs that are traditionally used are expensive, often costing $20 or more. One of skill in the art will appreciate that in a large high-rise building, for example, many plugs are required which increases plumbing costs. Another drawback is that plugs are often lost. More specifically, once the pressure test is complete, the pipe stub is severed between the plug and the tee connector. A portion of the pipe stub that remains interconnected to the tee is eventually interconnected to a plumbing fitting that leads to a sink or bathtub, for example. The unused portion of the pipe stub is commonly discarded where the plug is inadvertently discarded as well. 
         [0006]      FIG. 4  shows another embodiment of the prior art wherein a cap  50  is used. Here, the pipe stub  54  is interconnected to a tee connector  58  by bonding or any other known methods. Again, a portion of the pipe stub  54  is designed to remain interconnected to tee  58  and later accepts an elbow, for example. The cap  50  is commonly interconnected to the open end  62  of the pipe stub  54  with adhesive. Thus one drawback of using caps is that the plumber must wait for the bonding agent to cure, which adds delays and complexity to the plumber&#39;s task. Furthermore, if the open end  62  of the pipe stub  54  is not adequately flush, i.e., has burrs or an uneven surface, the cap  50  may not bond correctly, which may lead to false indications of leakage when the plumbing system is tested. In addition, if the cap is of a different material than the pipe stub  54  (a mismatch between ABS and PVC, for example) bonding may not be ideal. Leak tests are often performed at pressures that would compromise PVC pipes, which crack or rupture when exposed to pressures as low as about 5 to 6 PSI. Ideally, and interconnected plug or cap would disengage from the pipe stub before the pipe stub or interconnected pipes fracture. In some instances, however, bonding between the cap and the pipe stub can withstand the increased test pressure and the cap will remain on an over pressurization situation. 
         [0007]    Thus, is a long felt need in the field of plumbing to provide a method of quickly and cost-effective by sealing segments of a plumbing system for leak testing. The following disclosure describes an improved pipe stub that includes a diaphragm positioned adjacent to the open and of the pipe stub. Further, the contemplated pipe stub can be used multiple times for multiple leak tests, which reduce costs. 
       SUMMARY OF THE INVENTION 
       [0008]    It is one aspect of embodiments of the present invention to provide a pipe stub adapter with a removable diaphragm. More specifically, one embodiment of the present invention is a cylindrical pipe having a first end adapted to be secured to an opening in a plumbing system, and a second end with a removable diaphragm. The diaphragm may made out of plastic or any other similar material. The diaphragm is designed to be severed or otherwise removed from the pipe stub when testing is complete. The diaphragm may include a tab that is used to pull the diaphragm from the pipe stub or the diaphragm  80  can be cut from the pipe stub. 
         [0009]    In operation, the pipe stub is interconnected to an opening in a plumbing system and the plumbing system is leak tested. After the test is complete, the pipe stub is severed such that the remaining pipe can receive an elbow, for example. The remaining portion of the pipe stub, which includes the diaphragm, is then used in subsequent leak tests. The diaphragm of one embodiment of the present invention is designed to withstand about 2-100 PSI, which corresponds to the maximum head pressure expected when a 3-story house is tested. The diaphragm is, thus, designed to withstand multiple leak tests performed at lower pressures. The pipe stub may be of sufficient length such that it can be used, cut, and reused a number of times. To prevent over pressurization of the plumbing system and the pipe stub, the diaphragm of one embodiment present invention is designed to rupture at a pressure below the yield pressure of PVC or ABS pipe. Diaphragm rupture may be facilitated by grooves or frangible areas incorporated into the diaphragm. 
         [0010]    One of skill that will appreciate that the pipe stub may be closed on one end with features other than a diaphragm. For example, some embodiments of the present invention include a convex or a concave second end that is not elastomeric or flexible as described above. In this example, a rigid end is sonically welded, bonded, or otherwise interconnected to the pipe stub. Other embodiments of the present invention include sealing features that are integrally manufactured into the pipe stub. 
         [0011]    One embodiment of the present invention has a closed end that is frangible. For example, the end may possess an edge of reduced thickness that is interconnected to the inner surface or outer edge of the pipe stub. The plumber removes the end with a hammer, for example, when it is no longer needed. In other embodiments of the present invention, at least a portion of the outer surface of the pipe is comprised of threads that receive a cap. The cap may also be interconnected to the pipe stub by way of a bayonet fitting or any other common selective, nonpermanent interconnection mechanism known in the art. 
         [0012]    It is yet another aspect the present invention provides a pipe stub with an outer surface with identifying indicia. For example, the identifying indicia may include a series of markings indicating tube length which helps the plumber assess how far to insert the pipe stub into the tee, and how far the pipe stub should extend beyond the tee after the test is complete, for example. In addition, the end and/or sides of the pipe stub, may include the manufacturer&#39;s trademark or other markings Such markings may be molded into the pipe stub or end wall, for example. The markings may be also be used to provide a visual notification to the plumber that and otherwise innocuous piece of plumbing to be discarded is a pipe stub that can be used in a subsequent pressure test. The markings may also be used as a visual indicator that the plot pipe stub is interconnected to the plumbing system so that finished plumbing fixtures are not prematurely installed. 
         [0013]    Thus, it is one aspect of the present invention to provide a member for interconnection to a fluid delivery or fluid waste system, comprising: a cylindrical pipe stub having a first end and a second end, the first end being adapted for interconnection to the fluid delivery or fluid waste system; and a diaphragm associated with the second end of the pipe stub. 
         [0014]    It is yet another aspect of the present invention to provide a member for interconnection to a fluid delivery or fluid waste system, comprising: a pipe stub having a first end and a second end, the first end being adapted for interconnection to the fluid delivery or fluid waste system; and a closure member associated with the second end of the pipe stub. 
         [0015]    It is another aspect of the present invention to provide a method of selectively blocking fluid flow through a fluid delivery or fluid waste system, comprising: providing a hollow pipe stub adapter having a first length defined by a first end and a second end, the second end having a closure member associated therewith; interconnecting the first end of the pipe stub to a first opening in the fluid delivery or fluid waste system; performing a first leak test of the fluid delivery or fluid waste system; cutting the pipe stub to create a second pipe stub of a second length; interconnecting the second pipe stub to a second opening in the fluid delivery or fluid waste system; performing a second leak test of the fluid delivery or fluid waste system; and cutting the pipe stub to create a third pipe stub of a third length. 
         [0016]    The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions. 
           [0018]      FIG. 1  is a side elevation view of a plug of the prior art; 
           [0019]      FIG. 2  is the plug shown in  FIG. 1  wherein an elastomeric member positioned between two end plates has been expended outwardly; 
           [0020]      FIG. 3  is a cross-sectional view of a plumbing system that is interconnected to a pipe stub that is sealed with a plug; 
           [0021]      FIG. 4  is a cross-sectional view of a plumbing system with a pipe stub interconnected thereto that is sealed with a cap; 
           [0022]      FIG. 5  is a perspective view of a pipe stub of one embodiment of the present invention that is sealed on one end with a diaphragm; 
           [0023]      FIG. 6  is a cross-sectional view of  FIG. 5 ; 
           [0024]      FIG. 7  is a cross-sectional view of a pipe stub that is interconnected to a tee connector; 
           [0025]      FIG. 8  is a cross-sectional view of a tee interconnected to elbow via a remaining portion of the pipe stub; 
           [0026]      FIG. 9  is a cross-sectional view of a shortened pipe stub interconnected to a tee; 
           [0027]      FIG. 10  is a cross-sectional view of a pipe stub employing a convex end; 
           [0028]      FIG. 11  is a cross-sectional view of a pipe stub employing a convex end with a dimple; 
           [0029]      FIG. 12  is a cross-sectional view of a pipe stub employing a concave end; 
           [0030]      FIG. 13  is a cross-sectional view of a pipe stub employing an inwardly-disposed wall; 
           [0031]      FIG. 14  is a cross-sectional view of a pipe stub having a inwardly-disposed frangible wall; 
           [0032]      FIG. 15  is a cross-sectional view of a cross-sectional view of a pipe stub having a plurality threads that receive a sealing cap; 
           [0033]      FIG. 16  is a cross-sectional view of a cross-sectional view of a pipe stub that is selectively closed by a frangible wall; and 
           [0034]      FIG. 17  is a cross-sectional view of a pipe stub adapter having a plurality of outwardly and inwardly extending notches. 
       
    
    
       [0035]    To assist in the understanding of one embodiment of the present invention the following list of components and associated numbering found in the drawings is provided herein: 
         [0036]    # Component 
         [0037]      2  Plug 
         [0038]      6  First plate 
         [0039]      10  Second plate 
         [0040]      14  Elastomeric member 
         [0041]      18  Bolt 
         [0042]      22  Nut 
         [0043]      26  Washer 
         [0044]      30  Inner surface 
         [0045]      34  Pipe stub 
         [0046]      38  Tee connector 
         [0047]      50  Cap 
         [0048]      54  Pipe stub 
         [0049]      58  Tee connector 
         [0050]      62  Open-end 
         [0051]      70  Pipe stub 
         [0052]      74  First end 
         [0053]      78  Second end 
         [0054]      82  Tee connector 
         [0055]      86  Diaphragm 
         [0056]      90  Elbow 
         [0057]      94  Shortened pipe stub 
         [0058]      100  Pipe stub 
         [0059]      102  Closed-end 
         [0060]      110  Dimple 
         [0061]      114  Concave 
         [0062]      200  Pipe stub 
         [0063]      204  Wall 
         [0064]    # Component 
         [0065]      208  Second end 
         [0066]      212  First end 
         [0067]      216  Outer edge 
         [0068]      220  Inner surface 
         [0069]      300  Pipe stub 
         [0070]      304  Outer surface 
         [0071]      308  Threads 
         [0072]      312  Cap 
         [0073]      400  Pipe stub 
         [0074]      404  Wall 
         [0075]      408  second end 
         [0076]      412  Thinned portion 
         [0077]      500  Pipe stub 
         [0078]      504  Diaphragm 
         [0079]      508  Inner notch 
         [0080]      512  Outer notch 
         [0081]      516  Thinned portion 
         [0082]    It should be understood that the drawings are not necessarily to scale. In certain instances, details which are not necessary for an understanding of the invention or which render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. 
       DETAILED DESCRIPTION 
       [0083]    Referring now to  FIGS. 5-9 , one embodiment of a pipe stub  70  is shown that has a first end  74  and a second and  78 . The first end  74  is adapted for interconnection to a portion of a plumbing system, such as a tee connector  82 . The second end  78  of the pipe stub  70  is closed with a diaphragm  86  to prevent fluid flow through the pipe stub  70 . In operation, the diaphragm  86  may be cut or otherwise removed from the pipe stub  70  to allow fluid flow through the pipe stub  70  after a leak test is performed. The pipe stub  70  can be of any length or diameter. 
         [0084]      FIG. 7-9  show the pipe stub  70  interconnected to a portion of a plumbing system, in this instance, a tee connector  82 . The first end  74  of the pipe stub  70  is inserted into the tee connector  82  and bonded thereto using known methods. Thus, the second end  78  of the pipe stub  70  is blocked with the diaphragm  86 . After the leak tested performed, the pipe stub  70  is severed which leaves a portion of the pipe stub with a length (L 2 ) shorter than the initial length of the pipe stub (L 1 ). An elbow  90  or additional plumbing is eventually interconnected to the pipe. The elbow  90  is bonded to the pipe stub  70  using known techniques and adhesives. 
         [0085]    The shortened pipe stub  94  shown in  FIG. 9  can be then interconnected to another tee connector  82  of the plumbing system. For example, after the initial leak tests are performed, the shortened pipe stub  94  is used to test other segments of the plumbing system of the same building or the plumbing system of other buildings, which reduce costs. Referring now again to  FIG. 9 , the pipe stub has a length of (L 3 ), which is shorter than the length (L 1 ) of the pipe stub. After all tests are complete, the end of the pipe stub  74  shortened pipe stub  94  may be severed or the diaphragm  86  may be ruptured and an elbow or other plumbing component may be interconnected to the stub pipe stub as shown in  FIG. 8 . 
         [0086]      FIG. 10  shows another embodiment of the present invention wherein the pipe stub  100  is sealed with a convex end  102 . The closed end  102  is bonded or integrally molded to the pipe stub  100 . Similar to the process described above, this pipe stub  100  may be used in number of times wherein the length of the pipe stub  100  can be incrementally reduced after each test is complete. The closed end  102  of the pipe stub  100  may have a dimple  110  or possess indicia, such as the manufacturer&#39;s name, without departing from the scope of the invention. Further, as shown in  FIG. 12 , the closed and  102  of the pipe stub  100  may be concave  114 . 
         [0087]      FIGS. 13 and 14  show yet other embodiments of the present invention where the pipe stub  200  is selectively blocked with a wall positioned at the second end  208  of the pipe stub  200  or between the first end  212  and the second end  208  of the pipe stub. In one embodiment of the present invention, the wall  204  is frangible. More specifically, the wall  204  may have an outer edge  216  that is integrated onto or interconnected to the inner surface  224  of the pipe stub  200 . When the leak test is complete, the plumber may knock out to or otherwise disengage the frangible wall  204  from the inner surface  220  of the pipe stub  200  to provide an open fluid flow path. 
         [0088]      FIG. 15  shows yet another embodiment of the present invention where the pipe stub  300  has an outer surface  304  that is at least partially comprised of threads  308 . In operation, a cap  312  is threadably engaged to the pipe stub  300  before the leak test is performed. 
         [0089]      FIG. 16  is another embodiment of a pipe stub  400  that includes a frangible wall  404 . Here, the frangible wall  404  is associated with the second end  408  of the pipe stub  400 . Again, once the leak test is complete, the plumber may use a hammer and chisel or screwdriver to break the thinned portions  412  that interconnect the wall  404  to the second end of the pipe stub  400  to remove the frangible wall. 
         [0090]      FIG. 17  shows another embodiment of the present invention that employs a diaphragm  504 . However, one of skill that will appreciate other sealing methods as disclosed herein may be used. Here, the pipe stub  500  includes inner notches  508  and/or outer notches  512 . The notches facilitate cutting of the pipe stub  500 . For example, once leak test is complete, the plumber can cut through a notch  27  the pipe stub  500 . The thinned portions  516  provided by the inner and/or outer notches facilitates cutting. The notches also act a length a length indicator which allows the plumber to quickly identify the length of the remaining pipe stub. 
         [0091]    While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. Further, the invention(s) described herein is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.