Abstract:
A boot assembly that reliably seals the secondary containment area utilizing a split boot device that can be installed without disconnecting the primary piping is disclosed. The seal includes first and second containment housings, each supporting a pair of partial ring shaped seals. The containment housings can be positioned about the primary and secondary pipes from opposing sides thereof so that disconnection of the primary pipe is not required to secure the seal in place. A clamp secures the first containment housing relative to the second containment housing in a secured position in which a first pair of partial ring seals associated with the first containment housing and a second pair of partial ring shaped seals associated with the second containment housing cooperate to form a pair of continuous ring shaped sealing surfaces including a first continuous ring shaped sealing surface including one of the first pair of partial ring shaped seals and one of the second pair of partial ring shaped seals, and a second continuous ring shaped sealing surface including a second one of the first pair of partial ring shaped seals and a second one of the second pair of partial ring shaped seals.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is related to and claims the benefit under Title 35, U.S.C. 119(e) of U.S. Provisional Patent Application Ser. Nos. 61/540,493, entitled SPLIT TEST BOOT FOR TESTING THE SECONDARY CONTAINMENT FUEL CONTAINMENT PIPING filed on Sep. 28, 2011; 61/540,375 entitled SPLIT TEST BOOT FOR TESTING THE SECONDARY CONTAINMENT FUEL CONTAINMENT PIPING filed Sep. 28, 2011 and 61/651,285 entitled SPLIT TEST BOOT FOR TESTING THE SECONDARY CONTAINMENT FUEL CONTAINMENT PIPING filed May 24, 2012, the entire disclosures of which are hereby expressly incorporated by reference herein. 
     
    
     BACKGROUND/SUMMARY 
       [0002]    The present disclosure describes a novel test boot for sealing the secondary containment of a fuel containment piping system with a split boot assembly that can be installed without disconnecting the primary piping. 
         [0003]    Vehicle fuel is commonly conveyed from an underground storage tank to a fuel dispenser through a secondarily contained fuel pipe. The secondarily contained fuel pipe typically extends from a containment sump located above the underground storage tank to a containment sump located below the dispenser. Within either the dispenser sump or the tank sump, the secondary containment pipe is terminated in one of two ways either a closed type or an open type, as further described below. A primary/secondary piping arrangement as well as a sealing system utilized in conjunction with the same is disclosed in U.S. patent application Ser. No. 12/324,461, which published as U.S. Patent Application Publication No. 2009/0136286, entitled ENTRY BOOT, the entire disclosure of which is hereby expressly incorporated by reference herein. Other primary/secondary piping arrangements as well as sealing systems utilized in conjunction with the same are disclosed in U.S. Pat. Nos. 7,758,084 and 7,523,962, both entitled CONNECTION BETWEEN A PIPE AND A WALL, the entire disclosures of which are hereby expressly incorporated by reference herein. 
         [0004]    Secondary containment monitoring can be of a closed type, using a termination boot to seal the end of the secondary containment area for leak detection monitoring using a VPH method. VPH monitoring is an acronym for vacuum, pressure or hydrostatic monitoring. One of these three methods is typically used to monitor the closed volume between the primary and secondary pipes with a monitoring means that will indicate to a station owner or operator a potential leak of the primary piping system. An exemplary method and apparatus for monitoring for leaks is disclosed in U.S. Pat. Nos. 7,334,456 and 7,051,579, both entitled METHOD AND APPARATUS FOR CONTINUOUSLY MONITORING INTERSTITIAL REGIONS IN GASOLINE STORAGE FACILITIES AND PIPELINES, the entire disclosures of which are hereby expressly incorporated by reference herein. 
         [0005]    Secondary containment monitoring can also be of an open type allowing any fluid that may have leaked into the secondary containment pipe (e.g., from a leak in the primary pipe) to flow into the dispenser and/or tank sumps. A sensor located in the sump provides indication of a potential leak of the primary piping system. In this method, the ends of the secondary containment system are typically sealed on a periodic basis and verified by a service contractor to be leak tight using a VPH method. 
         [0006]    Whether utilizing a closed or open type system for monitoring a secondary containment piping system, a boot is installed to seal off the end of the secondary containment pipe in at least certain circumstances. 
         [0007]    Certain boot designs utilize a cylindrical, elastomeric boot that is installed onto the secondary piping system prior to the primary fitting connections being made to the ends of the piping system. Using this embodiment, one end of the elastomeric cylinder is clamped to the primary pipe and the other end clamped to the secondary pipe to seal off the secondary containment volume. While this is typically done with a cylindrical, elastomeric material, similar embodiments are also utilized. In order to replace the boot following damage or normal aging wear, the primary piping system must be disconnected in order to install a new boot. 
         [0008]    An improvement to this method is to utilize a split boot arrangement that allows both halves of a boot to be attached on either side of the pipe and subsequently sealed to the piping system in such a way that the secondary containment area is contained. 
         [0009]    The disclosed embodiment demonstrates a boot assembly that reliably seals the secondary containment area utilizing a split boot device that can be installed without disconnecting the primary piping. The seal includes first and second containment housings, each supporting a pair of partial ring shaped seals. The containment housings can be positioned about the primary and secondary pipes from opposing sides thereof so that disconnection of the primary pipe is not required to secure the seal in place. A clamp secures the first containment housing relative to the second containment housing in a secured position in which a first pair of partial ring seals associated with the first containment housing and a second pair of partial ring shaped seals associated with the second containment housing cooperate to form a pair of continuous ring shaped sealing surfaces including a first continuous ring shaped sealing surface including one of the first pair of partial ring shaped seals and one of the second pair of partial ring shaped seals, and a second continuous ring shaped sealing surface including a second one of the first pair of partial ring shaped seals and a second one of the second pair of partial ring shaped seals. 
         [0010]    In one form thereof, the present disclosure provides a seal for sealing the interstitial space formed between a primary pipe and a secondary pipe positioned about the primary pipe. The seal of this form of the present disclosure includes a first containment housing supporting a first seal, the first seal comprising a first pair of partial ring shaped seals, the first pair of partial ring shaped seals each forming a partial ring. The seal of this form of the present disclosure further includes a second containment housing supporting a second seal, the second seal comprising a second pair of partial ring shaped seals. A clamp sized and shaped to secure the first containment housing relative to the second containment housing in a secured position in which the first pair of partial ring shaped seals of the first seal and the second pair of partial ring shaped seals of the second seal cooperate to form a pair of continuous ring shaped sealing surfaces comprising a first continuous ring shaped sealing surface comprising a first one of the first pair of partial ring shaped seals and a first one of the second pair of partial ring shaped seals, and a second continuous ring shaped sealing surface comprising a second one of said first pair of partial ring shaped seals and a second one of said second pair of partial ring shaped seals may be provided. In the secured position the first containment housing and the second containment housing define a containment housing longitudinal axis. 
         [0011]    In alternative forms of the present disclosure, the first pair of partial ring shaped seals may span a first gasket and a second gasket, with the first pair of partial ring shaped seals joined by the first gasket and the second gasket. Further, the second pair of partial ring shaped seals may span a third gasket and a fourth gasket, the second pair of partial ring shaped seals joined by the third gasket and the fourth gasket. In this alternative form of the present disclosure, the clamp may sealingly engage the first gasket to the third gasket and the second gasket to the fourth gasket to form the pair of continuous ring shaped sealing surfaces. 
         [0012]    In embodiments of the present disclosure, the first gasket may comprise a first gasket seal surface and first gasket opposite surface opposite the first gasket seal surface, the first gasket seal surface and the first gasket opposite surface forming an angle oriented so that a thickness of the first gasket increases radially inwardly toward the containment housing longitudinal axis. The second, third and fourth gaskets may share the same configuration as previously described with respect to the first gasket. 
         [0013]    In embodiments of the present disclosure, the first continuous ring shaped sealing surface may define a first radius measured from the containment housing longitudinal axis and the second continuous ring shaped sealing surface may define a second radius measured from the containment housing longitudinal axis, with the first radius being smaller than the second radius so that the first continuous ring shaped sealing surface and the second continuous ring shaped sealing surface can simultaneously sealingly engage two different sized pipes. 
         [0014]    In certain alternative embodiments, each of the first pair of partial ring shaped seals and/or the second pair of partial ring shaped seals may have differing thicknesses such that a thickness of such seals at a certain point is greater than a thickness of these seals at another point. The differential thicknesses may be positioned such that the increased thicknesses are positioned 180° about the containment housing longitudinal axis from each other when the first containment housing and the second containment housing are in the secured position. In certain alternative embodiments, either or both of the first and second pair of partial ring shaped seals may define an inner diameter and an outer diameter, with the inner diameter eccentric to the outer diameter to form the aforementioned differential thicknesses. 
         [0015]    In certain forms of the present disclosure, the pairs of partial ring shaped seals may comprise O-rings, or dual lobed sealing rings presenting a pair of sealing surfaces. 
         [0016]    In alternative forms of the present disclosure, the first and second containment housings may include external radial protrusions having opposing ramp surfaces such that a thickness of the external radial protrusions increases radially inwardly toward the containment housing longitudinal axis. In such forms of the present disclosure, a clamp comprising a pair of interior ramp surfaces complementary to said opposing surfaces of the external radial protrusions may be utilized to clamp against the opposing ramp surfaces of the exterior radial protrusions to both axially and radially align the first containment housing with the second containment housing as the clamp secures the first containment housing and the second containment housing in the secured position. 
         [0017]    In certain forms of the present disclosure, one or both of the containment housings may include a cavity sized to receive the associated pair of partial ring shaped seals. The cavity may include a bevelled surface to accommodate an angled gasket oriented so that a thickness of the gasket increases radially inwardly toward the containment housing longitudinal axis. 
         [0018]    One or both of the containment housings of the present disclosure may include a fitting extending from the exterior surface of the containment housing and connected in fluid communication by a channel extending through a wall of the containment housing to an interior surface of the containment housing, the channel terminating at a location intermediate the first continuous ring shaped sealing surface and the second continuous ring shaped sealing surface. 
         [0019]    In alternative forms of the present disclosure, one or both of the containment housings may include a locator extending from an interior wall of the containment housing toward the containment housing longitudinal axis, the locator extending further inwardly toward the containment housing longitudinal axis than one of the continuous ring shaped sealing surfaces. 
         [0020]    In alternative forms of the present disclosure, the first containment housing includes a first pair of T-shaped protrusions extending from an exterior wall of the first containment housing and the second containment housing may include a second pair of T-shaped protrusions extending from an exterior wall of the second containment housing. The seal of this form of the present disclosure may further includes a first pair of O-rings, each of the first pair of O-rings positioned about one of the first pair of T-shaped protrusions and one of the second pair of T-shaped protrusions to hingedly connect the first containment housing to the second containment housing. In alternative forms of the present disclosure, the first containment housing may include a third pair of T-shaped protrusions extending from the exterior wall of the first containment housing and the second containment housing may include a fourth pair of T-shaped protrusions extending from the exterior wall of the second containment housing. In these alternative forms of the present disclosure, the seal may further comprise a second pair of O-rings, each of the second pair of O-rings selectively positioned about one of the third pair of T-shaped protrusions and one of the fourth pair of T-shaped protrusions to selectively secure the first containment housing to the second containment housing. 
         [0021]    In one form of the present disclosure, the seal disclosed herein may be utilized in combination with a fueling station including a primary pipe fluidly connecting an underground storage tank with a fuel dispenser and traversing an underground storage tank sump associated with the underground storage tank and a fuel dispenser sump associated with the fuel dispenser. In this form of the present disclosure, a secondary pipe providing secondary containment of the primary pipe may extend between the underground storage tank sump and the fuel dispenser sump. In this form of the present disclosure, the clamp secures the first containment housing relative to the second containment housing in the secured position so that the first continuous ring shaped sealing surface seals against the primary pipe and the second continuous ring shaped sealing surface seals against the secondary pipe. 
         [0022]    In one form of the present disclosure, the first containment housing may extend no more than 180° about the containment housing longitudinal axis and the second containment housing may extend no more than 180° about the containment housing longitudinal axis. 
         [0023]    In an alternative form of the present disclosure, an apparatus for conveying fluid includes a primary pipe, a secondary pipe surrounding the primary pipe and forming interstitial space therebetween and a split boot assembly. In this form of the present disclosure, the split boot assembly may include a first split boot half having an inner wall supporting a first pair of half ring seals and a second split boot having an inner wall supporting a second pair of half ring seals. The split boot assembly of this form of the present disclosure may further include a clamp engaging the first split boot half and the second split boot half to clamp the split boot assembly to the primary pipe and the secondary pipe such that the first pair of half ring seals seals against both the primary pipe and the secondary pipe and the second pair of half ring seals seals against both the primary pipe and the secondary pipe to thereby seal the interstitial space. 
         [0024]    In certain alternative embodiments, the clamp may comprise a tapered clamp engaging a tapered outer wall of the first split boot half and a tapered outer wall of the second split boot half to align the first split boot half to the second split boot half both radially and axially when the tapered clamp clamps the split boot assembly to the primary pipe and the secondary pipe. 
         [0025]    In certain forms of the present disclosure, the first pair of half ring seals and the second pair of half ring seals may comprise O-rings or dual lobed sealing rings comprising a pair of radially inwardly projecting sealing surfaces. 
         [0026]    In alternative forms of the present disclosure, one or both of the first split boot half and second split boot half may include a locator extending from an interior wall of the split boot half to a radially inward position, the locator extending further inwardly than an outer diameter of the secondary pipe. 
         [0027]    In alternative forms of the present disclosure, the first split boot half may be hingedly connected to the second split boot half. In exemplary embodiments, the first split boot half may include a pair of first split boot half T-shaped extensions and the second split boot half may include a pair of second split boot half T-shaped extensions. The apparatus of this form of the present disclosure may further include a pair of O-rings, each of the O-rings positioned about one of the pair of first split boot half T-shaped extensions and one of the pair of second split boot half T-shaped extensions to hingedly connect the first split boot half to the second split boot half. 
         [0028]    In certain alternative embodiments, each of the first pair of half ring seals and/or the second pair of half ring seals may have different thicknesses such that a thickness of such seals at a certain point is greater than a thickness of these seals at another point. The differential thicknesses may be positioned such that the increased thicknesses are positioned 180° about a longitudinal axis of the primary pipe from each other. In certain alternative embodiments, either or both of the first pair of half ring seals and the second pair of half ring seals may define an inner diameter and an outer diameter, with the inner diameter eccentric to the outer diameter. 
         [0029]    In alternative forms of the present disclosure, the first pair of half ring seals may span a first gasket and a second gasket, with the first pair of half ring seals joined by the first gasket and the second gasket. Further, the second pair of half ring seals may span a third gasket and a fourth gasket, the second pair of half ring seals joined by the third gasket and the fourth gasket. In this alternative form of the present disclosure, the clamp may sealingly engage the first gasket to the third gasket and the second gasket to the fourth gasket to form a pair of continuous ring shaped sealing surfaces. 
         [0030]    In embodiments of the present disclosure, the first gasket may comprise a first gasket seal surface and a first gasket opposite surface opposite the first gasket seal surface, the first gasket seal surface and the first gasket opposite surface forming an angle oriented so that a thickness of the first gasket increases radially inwardly toward a longitudinal axis of the primary pipe. The second, third and fourth gaskets may share the same configuration as previously described with respect to the first gasket. 
         [0031]    In certain forms of the present disclosure, one or both of the first split boot halves may include a cavity sized to receive the associated pair of half ring seals. The cavity may include a bevelled surface to accommodate an angled gasket oriented so that a thickness of the gasket increases radially inwardly toward the containment housing longitudinal axis. 
         [0032]    The split boot assembly may further include a fitting extending from an exterior surface of the split boot assembly and connected in fluid communication by a channel through a wall of the split boot assembly to an interior surface of the split boot assembly to fluidly connect the fitting to the interstitial space formed between the primary pipe and the secondary pipe. 
         [0033]    In a further alternative form of the present disclosure, a sealing ring includes a first gasket section, a second gasket section, and a partial ring spanning the first gasket section and the second gasket section and extending through an arc about a longitudinal axis spaced from the partial ring seal. In this form of the present disclosure, the partial ring seal includes a first radial thickness perpendicular to the longitudinal axis adjacent to the first gasket section and a second radial thickness perpendicular to the longitudinal axis and located between the first gasket section and the second gasket section, the second radial thickness being greater than the first radial thickness. 
         [0034]    In an alternative form of the present disclosure, the second, increased thickness is midway between the first gasket section and the second gasket section. The sealing ring may further include a second partial ring seal spanning the first gasket section and the second gasket section and extending through the same arc as the first partial ring seal. In an alternative form of the present disclosure, one or both of the first gasket section and the second gasket section may include a first face and an opposing second face, with the first face diverging from the second face in a radially inward direction toward the longitudinal axis so that the first face has an increasingly greater thickness toward the longitudinal axis. 
         [0035]    The above and other features of the present disclosure, which alone or in any combination may comprise patentable subject matter, will become apparent from the following description and the attached drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0036]    The above-mentioned and other features and advantages of this disclosure, and the manner of attaining them, will become more apparent and the disclosure itself will be better understood by reference to the following descriptions of embodiments of the disclosure taken in conjunction with the accompanying drawings, wherein: 
           [0037]      FIG. 1  is a partial perspective view illustrating a double walled pipe; 
           [0038]      FIG. 2  is a partial perspective view of the double walled pipe of  FIG. 1  illustrating a split boot assembly secured thereto; 
           [0039]      FIG. 3  is a half section of a split boot assembly in accordance with an exemplary embodiment of the present disclosure, including a rigid containment housing and an elastomeric seal; 
           [0040]      FIG. 4  illustrates a split boot assembly in operative form with a tapered clamp securing a pair of containment housings to form two continuous seals; 
           [0041]      FIG. 5  is a cross-sectional view illustrating the split boot assembly of the present disclosure secured to a double walled pipe assembly; 
           [0042]      FIG. 6  is a representation of a fueling station illustrating connection of a fuel dispenser to an underground storage tank; 
           [0043]      FIG. 7  is an illustration of an alternative embodiment split boot half in accordance with the present disclosure; 
           [0044]      FIG. 8  is a radial elevational view of the split boot half illustrated in  FIG. 7 ; 
           [0045]      FIG. 9  is an axial elevational view of the split boot half illustrated in  FIG. 7 ; 
           [0046]      FIG. 10  is another radial elevational view of the split boot half illustrated in  FIG. 7 ; 
           [0047]      FIG. 11  is a sectional view of the split boot half illustrated in  FIG. 10 ; 
           [0048]      FIG. 12  is another sectional view of the split boot half illustrated in  FIGS. 7-11 ; 
           [0049]      FIG. 13  is an axial elevational view of a partial sealing ring of the present disclosure; 
           [0050]      FIG. 14  is a fragmented view illustrating a partial sealing ring connected to a containment housing in accordance with the present disclosure; 
           [0051]      FIG. 15  is a cross-sectional view illustrating an embodiment of the split boot assembly of the present disclosure assembled to a double walled pipe; 
           [0052]      FIG. 16  is a cross-sectional view of the assembly illustrated in  FIG. 15 ; 
           [0053]      FIG. 17  is an alternative cross-sectional view illustrating the assembly shown in  FIG. 15 ; 
           [0054]      FIG. 18  is a perspective view illustrating an alternative embodiment split boot assembly in accordance with the present disclosure; and 
           [0055]      FIG. 19  is a cross-sectional view illustrating assembly of a pair of hingedly connected container housings to a double walled pipe. 
       
    
    
       [0056]    Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate exemplary embodiments of the disclosure, and such exemplifications are not to be construed as limiting the scope of the disclosure in any manner. 
       DETAILED DESCRIPTION 
       [0057]    The present disclosure provides a seal useable for sealing the interstitial space formed between a primary pipe and a secondary pipe positioned about the primary pipe. 
         [0058]    A typical fuel piping system is shown in  FIG. 1 . Primary pipe  10  is centrally located within an arrangement of coaxially located pipes. Adjacent to primary pipe  10  is secondary containment pipe  12 . Scuff guard  14  is also depicted and serves to protect the secondary pipe from scratches that could occur during installation. 
         [0059]    Split boot assembly  16  is shown in  FIG. 2  assembled to the piping system. Split boot assembly  16  is located in such a position as to be capable of providing a seal between boot assembly  16  and primary pipe  10  on one end and boot assembly  16  and secondary pipe  12  on the second end. Centrally located on split boot assembly  16  is ring  18  for positioning tapered clamp  20  ( FIG. 4 ).  FIG. 3  illustrates a half section of boot assembly  16  that includes rigid containment housing  22  and elastomeric seal  24 . Housing  22  and seal  24  are constructed such that when combined with a similar half section can form a leak tight seal of the secondary containment volume, i.e., the interstitial space defined between primary pipe  10  and secondary pipe  12 . Specifically, elastomeric seal  24  includes O-ring, quad-ring, or dual-lobed over molded seal halves  26  connected by flat gasket sections  28 . 
         [0060]      FIG. 3  illustrates a half section of boot assembly  16  that includes rigid containment housing  22  and elastomeric seal  24 . Containment housing  22  may include a cavity or indentation sized to closely match the outer contours of elastomeric seal  24 . In certain embodiments, elastomeric seal  24  may be interference fit into such a cavity, with a portion of the seal exposed to effect sealing as described herein. In embodiments of the present disclosure, containment housing  22  is formed of plastic such as high density polyethylene (HDPE), e.g., PE  100 . Glass reinforced polymers and nylons may also be used to form containment housing  22 . Elastomeric seal  24  can be formed of a variety of materials routinely used for sealing in the petroleum industry, such as various rubber and rubber compounds. Housing  22  and seal  24  are constructed such that when combined with a similar half section can form a leak tight seal of the secondary containment volume. Specifically, elastomeric seal  24  includes O-ring halves  26  connected by flat gasket sections  28 . In an exemplary embodiment, and as illustrated in  FIGS. 4 ,  9  and  16 - 19 , each section of split boot assembly  16  may be formed by a containment housing extending no more than 180° about the longitudinal axis of split boot assembly  16  (which, will be generally coincident with the longitudinal axis of primary pipe  10 , in use). 
         [0061]    As shown in  FIG. 4 , split boot assembly  16  is assembled and secured with tapered clamp  20 . When tightened, tapered clamp  20  ensures alignment of the two half sections of boot assembly  16  along both longitudinal axis L and radial axis R while providing compression of the assembly and, consequently, compression of elastomeric seals  24  against primary pipe  10  and secondary pipe  12 . 
         [0062]    Since tapered clamp  20  provides both axial and radial alignment, the ends of the seal assembly form together in order to create a single seal path that duplicates the function of a full O-ring, quad-ring, or dual-lobed over molded seal with two half O-ring seals on each end of the split boot. This enhanced alignment ensures proper sealing. 
         [0063]    The ends of the half O-rings  26  are attached to flat gasket sections  28  that are used to contain and position the ends of the half O-rings and provide for sealing therebetween. In an embodiment of the present disclosure, when the halves of split boot assembly  16  are secured in operable relationship to primary pipe  10  and secondary pipe  12  to provide sealing therebetween, flat gasket sections  28  of the two elastomeric seals  24  are sealingly pressed against each other so that associated pairs of half O-rings  26  of the two elastomeric seals  24  form a seal about the entire circumference of the pipe against which they are positioned. This cooperation of the two elastomeric seals  24  to form a continuous seal through the split in split boot assembly  16  is illustrated in  FIG. 4 . In this way, the two elastomeric seals  24  cooperate to form two continuous sealing surfaces about a full 360 degrees of rotation. 
         [0064]    In order to maximize the performance of the sealing interface between the two half O-rings, it is envisioned that small raised crescent rings could be included to ensure concentrated sealing at the edges of the O-ring. 
         [0065]    Referring to  FIG. 5 , a half section of boot assembly  16  is illustrated in a sealing configuration with primary pipe  10  and secondary pipe  12 .  FIG. 5  illustrates the two internal diameters of each half section of boot assembly  16  which allow for placement of split boot assembly  16  in close proximity to primary pipe  10  and secondary pipe  12  simultaneously. As illustrated in  FIG. 5 , ring  18  extends radially outwardly from the outer diameter of rigid containment housing  22  of each half of split boot assembly  16  and includes a pair of outwardly facing ramp surfaces  30 . Similarly, tapered clamp  20  includes interior ramp surfaces  32 . When assembled, ramp surfaces  30  and ramp surfaces  32  form a similar or, in certain circumstances, identical angle relative to radial axis R, which, in use, is oriented perpendicular to the longitudinal axis L of primary pipe  10  and secondary pipe  12  and illustrated in  FIG. 4 . 
         [0066]    Referring to  FIG. 4 , tapered clamp  20  includes ends  33  which can be brought together to compress tapered clamp  20  against a pair of half sections of boot assembly  16  to tightly secure split boot assembly  16  to primary pipe  10  and secondary pipe  12  as illustrated in  FIG. 5 . Tapered clamp  20  may be flexible enough so that ends  33  may be sufficiently separated to allow tapered clamp  20  to be positioned about the exterior of split boot assembly  16 . Alternatively, tapered clamp  20  may be formed by two clamp halves which are hingedly connected at a position spaced, e.g., 180° from ends  33  to allow for tapered clamp  20  to be opened and positioned about split boot assembly  16 .  FIG. 17  illustrates an exemplary hinge  72 . With tapered clamp  20  positioned about split boot assembly  16 , ends  33  of tapered clamp  20  may be pulled together so that ramp surfaces  32  of tapered clamp  20  act against ramp surfaces  30  of ring  18  to both radially and axially align the halves of split boot assembly  16  as described above. Tapered clamp  20  is sized such that it will provide compressive force about the entire perimeter of split boot assembly  16  and to the seals positioned therein. Ramp surfaces  32  of tapered clamp  20  and ramp surfaces  30  of ring  18  can be symmetrical relative to a radial axis to facilitate radial and axial alignment of the halves of split boot assembly  16 . A variety of fasteners, such as a lag bolt/nut (e.g., a wing nut) may be utilized to pull ends  33  toward one another to effect compression of split boot assembly  16  and bring split boot assembly  16  into sealing engagement with primary pipe  10  and secondary pipe  12 . 
         [0067]    In certain embodiments, split boot assembly  16  includes fitting  36  to allow for connection to a port fluidly connected to an interstitial space formed between primary pipe  10  and secondary pipe  12  and facilitate VPH monitoring. This is further illustrated in  FIG. 15 . 
         [0068]      FIG. 6  schematically illustrates components of a fuel station including fuel dispenser  38 , underground storage tank  40  and underground piping system  42 . In this arrangement, underground piping system  42  fluidly connects fuel dispenser  38  to underground storage tank  40  so that fuel stored in underground storage tank  40  may be dispensed to vehicles via the nozzle of fuel dispenser  38 . To effect fluid connection of underground storage tank  40  to fuel dispenser  38 , primary pipe  10  maintains connection to and allows fluid communication between underground storage tank  40  and fuel dispenser  38 . In prior configurations utilizing a full (non-split) test boot, primary pipe  10  would have to be disconnected from the piping system fluidly connecting underground storage tank  40  to fuel dispenser  38  to allow for replacement of a damaged test boot. Advantageously, the split test boot of the present disclosure does not require disconnection of primary pipe  10  to allow for replacement of a damaged split test boot. 
         [0069]    In the exemplary embodiment illustrated, underground piping system  42  comprises double walled pipe as previously described. In addition to secondary pipe  12 , tank sump  44  and dispenser sump  46  form a part of a secondary containment system. Tank sump  44  contains an access for filling underground storage tank  40  as well as piping (primary pipe  10 ) for conveying fuel from underground storage tank  40  to fuel dispenser  38 . Underground piping system  42  includes double walled pipe  48  spanning tank sump  44  and dispenser sump  46 , with secondary pipe  12  terminating at either end in tank sump  44  and dispenser sump  46 . Primary pipe  10  fully extends from underground storage tank  40  to dispenser  38 . Secondary pipe  12  terminates within tank sump  44  and dispenser sump  46  at split boot assemblies  16 . In alternative embodiments, secondary pipe  12  does not terminate at a test boot but rather terminates within the respective sump so that any fluid flowing in the interstitial space between primary pipe  10  and secondary pipe  12  will be collected in one of tank sump  44  and dispenser sump  46 . To seal against leaks, tank sump  44  and dispenser sump  46  employ penetration seals  50 . These sump penetration seals can take the form of those disclosed in U.S. Patent Application Publication No. 2009/0136286 and U.S. Pat. Nos. 7,758,084 and 7,523,962, the entire disclosures of which are hereby expressly incorporated by reference herein. 
         [0070]    To convey fuel contained in underground storage tank  40  to fuel dispenser  38  via primary pipe  10 , a pump may be positioned in tank sump  44  or be submersed in underground storage tank  40 . 
         [0071]    To monitor for leaks in double walled pipe  48 , split boot assemblies  16  may be communicatively connected via connections  52  to monitoring system  54 . Monitoring system  54  may form a part of a leak detection system such as the leak detection system disclosed in U.S. Pat. Nos. 7,334,456 and 7,051,579, both entitled “Method and Apparatus for Continuously Monitoring Interstitial Regions in Gasoline Storage Facilities and Pipe Lines”, the entire disclosures of which are hereby expressly incorporated by reference herein. 
         [0072]      FIG. 7  illustrates boot half  56 , a pair of which cooperate to form a split boot assembly. Boot half  56  illustrated in  FIG. 7  forms a part of an alternative embodiment split boot assembly such as split boot assembly  16   a  illustrated in  FIGS. 15-19 . Split boot assembly  16   a  shares many common features with split boot assembly  16  described above. Shared features are denoted with the same reference number followed by a reference letter. 
         [0073]    Referring to  FIG. 11 , boot half  56  includes a pair of seal halves  27 . Seal halves  27  perform the same function as O-ring halves  26  described above and are secured to rigid containment housing  22   a  in the same fashion as O-ring halves are secured to rigid containment housing  22 . Unless specified, split boot assemblies  16 ,  16   a  share common features and functionality, and are assembled in the same way. Seal halves  27  each include dual sealing surfaces  27   a ,  27   b  extending radially inward therefrom. Sealing surfaces  27   a ,  27   b  are, in use, pressed against one of primary pipe  10  and secondary pipe  12  to form a sealing engagement therewith. As with O-ring halves  26  described above, seal halves  27  are joined by flat gasket sections  28   a  as illustrated in  FIGS. 7-9 . 
         [0074]    Flat gasket section  28   a  is illustrated in detail in  FIG. 14 . As illustrated in  FIG. 14 , flat gasket section  28   a  includes seal surface  29 . Seal surface  29  extends upwardly from junction surface  58  of boot half  56  and forms an angle α therewith. In one exemplary embodiment, angle α measures 6°. In this embodiment, more material compression is experienced at a radially inward most portion of adjacent to sealing surfaces  27   a ,  27   b  when a pair of boot halves  56  are joined together to form split boot assembly  16   a , whereas less material is compressed at a radially outward most portion of sealing surfaces  27   a ,  27   b . In this way, angling of seal surface  29  provides maximum sealing adjacent to primary pipe  10  and secondary pipe  12 . In an exemplary embodiment, seal surface  29  forms an angle θ with a surface of flat gasket section  28   a  opposite seal surface  29 . In one exemplary embodiment angle θ measures 12°. This 12° angle provides additional material at a radially inward position of flat gasket section relative to a radially outwardly position to allow for further compression of flat gasket section  28   a  at a radially inward most position of seal surfaces  29  of seal halves  27 . As illustrated in  FIG. 14 , containment housing  22   a  may include a bevelled surface to accommodate angle θ. As illustrated in  FIG. 7 , sealing surfaces  27   a ,  27   b  transition from the raised convex surfaces illustrated in  FIG. 11  to a flattened section adjacent to flat gasket sections  28   a  to further provide additional surface area for sealing between adjacent flat gasket sections  28   a  on a pair of elastomeric seals  24   a.    
         [0075]      FIG. 13  is an axial elevational view of elastomeric seal  24   a  of one exemplary embodiment of the present disclosure. As illustrated in  FIG. 13 , elastomeric seal  24   a  includes an inner diameter having a center which is eccentric to the center of the radius of the outer diameter of elastomeric seal  24   a . Owing to this eccentricity, thickness T 2  of each seal half  27  is greater than thickness T 1 , with T 2  being the thickest part of seal half  27  and positioned 90° from seal surface  29 . Elastomeric seal  24   a  is particularly useful for sealing a primary pipe and/or a secondary pipe which is out of round. Specifically, if the primary pipe and/or the secondary pipe which is to be sealed by split boot assembly  16   a  has been made oblong due to deformation thereof, split boot assembly  16   a  may be positioned thereabout such that thickness T 2  is positioned adjacent to the short radial axis of the oblong pipe. In this way, more robust sealing can be achieved. Referring to  FIG. 12 , the center of the radial channel into which seal halves  27  are positioned corresponds with the center of the outer diameter of seal half  27 . Therefore, the center of the inner diameter of seal half  27  is eccentric to the center of the radius of the groove formed in boot half  56  into which seal half  27  is positioned. In this way, the inner diameter of seal half  27  protrudes further radially inwardly at a position 90° from flat gasket sections  28   a  than at a position adjacent to flat gasket sections  28  to further facilitate sealing a pipe that is out of round as described above. Further, if thickness T 2  is positioned adjacent to the long axis of a pipe that is out of round, the increased thickness of elastomeric seal  24   a  will provide significant forces along the long axis to urge the pipe back to round. 
         [0076]    Double walled pipe  48  can be made in accordance with the disclosure of U.S. Pat. No. 5,865,216, issued Feb. 2, 1999 and entitled SYSTEM FOR HOUSING SECONDARILY CONTAINED FLEXIBLE PIPING, the entire disclosure of which is expressly incorporated by reference herein. Additionally, pipes used with the test boot of the present disclosure may be made from Nylon-12. Further, pipes used with the test boot of the present disclosure may be made in accordance with the disclosure of U.S. Pat. Nos. 5,297,896 and 5,527,130, issued Mar. 29, 1994 and Jun. 18, 1996, respectively and both entitled ENVIRONMENTALLY SAFE UNDERGROUND PIPING SYSTEM, the entire disclosures of which are hereby explicitly incorporated by reference herein. Further, pipes used with the test boot of the present disclosure may be made in accordance with the disclosures of U.S. Pat. Nos. 6,029,505 issued Feb. 29, 2000, 5,911,155 issued Jun. 8, 1999 and 5,398,976 issued Mar. 21, 1995 each entitled CONNECTING DEVICE FOR PIPE ASSEMBLIES, the entire disclosures of which are hereby explicitly incorporated by reference herein. Additionally, pipes used with the test boot of the present disclosure may be made in accordance with the disclosure of U.S. Pat. No. 5,590,981 issued Jan. 7, 1997 and entitled DOUBLE-CONTAINMENT UNDERGROUND PIPING SYSTEM, the entire disclosure of which is expressly incorporated by reference herein. Further, pipes used with the test boot of the present disclosure may be made in accordance with the disclosure of U.S. Pat. No. 6,116,817 issued Sep. 12, 2000 and entitled HYDROCARBON FUEL PIPING SYSTEM WITH A FLEXIBLE INNER PIPE AND AN OUTER PIPE, the entire disclosure of which is expressly incorporated by reference herein. 
         [0077]    While the exemplary embodiment elastomeric seal  24   a  of the present disclosure is formed with a constant inner diameter (along seal surfaces  27   a  and  27   b ) and a constant outer diameter positioned within a constant diameter groove formed in rigid containment housing  22 , a seal of variable inner and/or outer diameter may be employed to achieve variable radial extension toward a longitudinal axis of the test boot and/or variable seal thickness about the circumference of the seal. 
         [0078]    As illustrated in  FIGS. 9 and 10 , flat gasket section  28   a  extends a distance d from the terminal end of a half of split boot assembly  16   a . In one exemplary embodiment, distance d is 0.06 inches at the radially outward most point of flat gasket section  28   a . This thickness, coupled with the angular orientation of flat gasket sections  28   a  described above allows split test boot assembly  16  to be utilized with a variety of pipe sizes by providing a collapsible zone that can be sealed at less compression on the largest pipes and full compression on the smallest pipes within the tolerance. 
         [0079]      FIG. 15  is a cross-sectional view illustrating boot half  56  secured about primary pipe  10  and secondary pipe  12  to seal interstitial space  11  therebetween.  FIG. 15  illustrates the varying inner diameters of seal halves  27 . These varying diameters are represented by radiuses R 1 , R 2  measured from longitudinal axis L in  FIG. 8 . As illustrated, one of seal halves  27  protrudes further radially inward than the other seal half. The seal half which protrudes the furthest in a radially inward direction is associated with primary pipe  10 , while the other seal half is associated with secondary pipe  12 . In this way, consistent sealing against primary pipe  10  and secondary pipe  12  can be achieved.  FIG. 15  further illustrates fitting  36  fluidly connected via channel  70  to interstitial space  11  to allow for connection of a monitoring system to interstitial space  11 . In an alternative (“open-type”) embodiment, piping may be connected to fitting  36  so that any fluid contained within interstitial space  11  may be discharged into the relevant sump. 
         [0080]      FIG. 12  illustrates locators  60  which protrude radially inwardly from an inner wall of boot half  56 . Locators  60  are useful in positioning primary pipe  10 . Specifically, primary pipe  10  bears against the radially inward surfaces of locators  60 . Further, locators  60  may serve as an axial stop for the insertion of secondary pipe  12  into split boot assembly  16   a.    
         [0081]    As illustrated in  FIGS. 7-10  and  16 - 19 , each boot half  56  includes a pair of radially outward T-shaped extensions  62  at each terminal end thereof. Referring to  FIG. 18 , when a pair of boot halves  56  are joined to form a complete split boot assembly  16   a , O-rings  64  can be positioned over adjacent T-shaped extensions  62  on each boot half  56 . To facilitate positioning of split boot assembly  56  about double walled pipe  48 , a pair of O-rings  64  can be positioned about T-shaped extension  62  at one of the two terminal ends of boot halves  56 . As illustrated in  FIG. 19 , this allows for hinging of boot halves  56  relative to each other to facilitate positioning of split boot assembly  16   a  about double walled pipe  48 . When a pair of boot halves  56  are positioned in the desired position, a second pair of O-rings  64  can be positioned about the remaining pairs of T-shaped extensions  62  to temporarily hold split boot assembly  16   a  in position while tapered clamp  20  is being positioned as described above. 
         [0082]    O-rings  64  are sized to fit snugly about a pair of adjacent upstanding legs  66  of T-shaped extensions  62 , but have sufficient resiliency to allow expansion to a size to be pulled over transverse leg  68  of one of a pair of adjacent T-shaped extensions  62  while positioned adjacent to the upstanding leg ( 66 ) of the other of the adjacent T-shaped extensions. Once seated about a pair of adjacent upstanding legs  66  of a pair of adjacent T-shaped extensions  62  as illustrated, e.g., in  FIGS. 21 ,  23  and  24 , O-rings  64  have sufficient resiliency to allow boot halves  56  to hinge relative to each other as illustrated in  24 . This hinging of boot halves  56  allows boot halves  56  to be easily positioned about double walled pipe  48  in the tight confines of a sump  44 ,  46 . 
         [0083]    While described with reference to a boot embodiment formed of two halves, the split boot of the present disclosure could be split into any multiple of pieces, if desired. Further the pieces of the split test boot of the present disclosure could be interconnected by, e.g., a living hinge, such that the portions of the split test boot are not discreet from one another, but rather are integrally connected by the living hinge, which forms a part of two portions of a test boot body, but which is sufficiently resilient to allow one portion of the split test boot body to hinge relative to another portion of the split test boot body. 
         [0084]    While the present disclosure has been described as having exemplary designs, the present disclosure can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains.