Abstract:
In accordance with a particular embodiment of the present invention, an underground tank shroud assembly includes a shroud comprising a top region and a base region. The shroud is configured to circumferentially enclose a riser of an underground tank. The assembly also includes a shroud lid configured to cover the top region of the shroud. The shroud lid is coupled to the shroud at a first hinge coupling and a second hinge coupling.

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to underground tanks and, more particularly, to an underground tank shroud assembly.  
       BACKGROUND OF THE INVENTION  
       [0002]     Underground tanks are used to store various materials beneath the earth&#39;s surface. For example, underground tanks may be used to store liquid propane gas (LPG) for residential or commercial purposes. Underground tanks generally include a riser extending towards the surface that may be protected by a metallic shroud. The metallic shroud tends to corrode over time while underground. The shroud includes a small lid that opens to provide access to valves positioned at the top of the riser.  
       SUMMARY OF THE INVENTION  
       [0003]     The present invention provides an underground tank shroud assembly that substantially eliminates or reduces at least some of the disadvantages and problems associated with previous shroud assemblies.  
         [0004]     In accordance with a particular embodiment of the present invention, an underground tank shroud assembly includes a shroud comprising a top region and a base region. The shroud is configured to circumferentially enclose a riser of an underground tank. The assembly also includes a shroud lid configured to cover the top region of the shroud. The shroud lid is coupled to the shroud at a first hinge coupling and a second hinge coupling.  
         [0005]     The shroud lid may be operable to decouple from the shroud at either the first hinge coupling or the second hinge coupling to open the shroud lid. The shroud lid may be operable to pivot with respect to the shroud at the second hinge coupling when the shroud lid is opened if the shroud lid is decoupled from the shroud at the first hinge coupling to open the shroud lid, and the shroud lid may be operable to pivot with respect to the shroud at the first hinge coupling when the shroud lid is opened if the shroud lid is decoupled from the shroud at the second hinge coupling to open the shroud lid. Each hinge coupling may comprise a nut and bolt assembly to couple the shroud lid to the shroud.  
         [0006]     The shroud may comprise plastic. The plastic may comprise polyurethane or polyethylene. The shroud may comprise a generally conical shape. A bottom edge of the base region may be configured to conform to a convex top surface of the underground tank. The underground tank may be configured to store liquid propane gas (LPG). The shroud may comprise at least one bracket slot proximate the base region. The at least one bracket slot may be configured to receive a respective bracket of the underground tank to hold the shroud into place when installed.  
         [0007]     In accordance with another embodiment, an underground tank and shroud assembly comprises an underground tank. The underground tank comprises a tank body and a riser extending substantially vertically from the body towards a surface of the earth. The tank and shroud assembly also comprises a shroud assembly comprising a shroud comprising a top region and a base region. The shroud is configured to circumferentially enclose the riser of the underground tank. The shroud assembly also comprises a shroud lid configured to cover the top region of the shroud. The shroud lid is coupled to the shroud at a first hinge coupling and a second hinge coupling.  
         [0008]     Technical advantages of particular embodiments of the present invention include a shroud assembly comprising a lid and a shroud for circumferentially enclosing a riser of an underground tank. The shroud and lid are made of a plastic material which decreases the possibility of corrosion beneath the earth&#39;s surface. Accordingly, the shroud and lid may be used for longer periods of time. The lid may be coupled to the shroud using multiple hinge couplings to provide more than one location from which the lid may be opened. Accordingly, a user may choose the more accessible hinge coupling as the coupling at which the user will open the lid.  
         [0009]     Other technical advantages will be readily apparent to one skilled in the art from the following figures, descriptions and claims. Moreover, while specific advantages have been enumerated above, various embodiments may include all, some or none of the enumerated advantages.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     For a more complete understanding of particular embodiments of the invention and their advantages, reference is now made to the following descriptions, taken in conjunction with the accompanying drawings, in which:  
         [0011]      FIG. 1  illustrates a shroud assembly and an underground tank, in accordance with a particular embodiment of the present invention;  
         [0012]      FIG. 2  illustrates the shroud assembly of  FIG. 1  with the lid in an open position, in accordance with a particular embodiment of the present invention;  
         [0013]      FIG. 3  is an exploded view illustrating one hinge coupling of the shroud assembly of  FIG. 1 , in accordance with a particular embodiment of the present invention;  
         [0014]      FIG. 4  is a cross-sectional view of the shroud assembly of  FIG. 1  taken along line  4 - 4  of  FIG. 1 , in accordance with a particular embodiment;  
         [0015]      FIG. 5  illustrates a shroud assembly and an underground tank, in accordance with another embodiment of the present invention;  
         [0016]      FIG. 6  illustrates the underside of the lid of the shroud assembly of  FIG. 5 , in accordance with a particular embodiment of the present invention;  
         [0017]      FIG. 7A  is an exploded view illustrating the lid and shroud of  FIG. 5 , in accordance with a particular embodiment of the present invention; and  
         [0018]      FIG. 7B  is an exploded view further illustrating a lug slot of the shroud lid of  FIG. 7A , in accordance with a particular embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]      FIG. 1  illustrates a shroud assembly  12  for use with an underground tank  26 , in accordance with a particular embodiment of the present invention. When underground tank  26  is positioned beneath the earth&#39;s surface, shroud assembly  12  is positioned to circumferentially enclose a riser  30  of underground tank  26 . Shroud assembly  12  comprises a shroud  14  and a lid  16 . In particular embodiments, shroud  14  and lid  16  may comprise a plastic material, such as polyurethane or polyethylene, and shroud  14  may be manufactured using a rotary mold method. In some embodiments, shroud  14  and lid  16  may substantially or completely comprise a plastic material. In particular embodiments, shroud  14  and lid  16  may not comprise any metallic material. Manufacturing shroud assembly  12  with a plastic material decreases the possibility of corrosion when the shroud assembly has been underground for a substantial period of time. Accordingly, the shroud assembly may have a longer useful life. In the illustrated embodiment, the side of shroud  14  is tapered such that the shroud comprises a generally conical shape. Such tapering facilitates stacking of multiple shrouds which reduces shipping and handling labor and expenses. Shrouds in accordance with other embodiments may, however, comprise other shapes or configurations.  
         [0020]     Underground tank  26  may store liquid propane gas (LPG) or other composition below the earth&#39;s surface. The storage capacity of tank  26  may vary in different embodiments. In a particular embodiment, underground tank  26  may have a storage capacity of 120 to 2000 water gallons (wg). Underground tank  26  comprises a body  28  for such storage and a riser  30  extending generally vertical towards the earth&#39;s surface when the tank is installed underground. The use of riser  30  enables tank  26  to be accessed from the earth&#39;s surface while body  28  is positioned below a freeze depth below the earth&#39;s surface. In particular embodiments, riser  30  may have a length ranging from fourteen to twenty-eight inches. Body  28  and riser  30  of underground tank  26  comprise carbon steel; however in other embodiments components of underground tanks may comprise other compositions. Underground tank  26  includes a withdrawal valve  31  for withdrawal of the stored composition, such as LPG. The top of riser  30  may include a plurality of valves, such as a relief valve  32 . Particular embodiments include a service valve at the top of riser  30  serving several purposes, including a service opening to which a gas line may be connected.  
         [0021]     A bottom edge  17  of shroud  14  is shaped to conform to a convex surface of body  28  of tank  26 . Shroud  14  includes a cutout portion  18  at its base to provide a recess through which a gas line may pass for connection with withdrawal valve  31  of tank  26 . Shroud  14  also includes slots  20  through which brackets  34  of underground tank  26  may slide during installation of shroud  14 . The positioning of brackets  34  within slots  20  prevents rotation or other movement of the shroud while underground. In the illustrated embodiment, brackets  34  are L-shaped brackets. In particular embodiments, brackets  34  may have different widths from each other to slide in slots  20  having different widths so that shroud assembly  12  will only be able to be positioned upon the tank in one manner. This ensures that opening  22  is positioned above valve  32  when the shroud assembly is in place. Other embodiments may include other components to hold shroud  14  in place around riser  30  of tank  26 . Soil packed around shroud  14  may also aid in holding shroud  14  in place when installed underground.  
         [0022]     Lid  16  of shroud assembly  12  comprises a general circular shape in the illustrated embodiment. Lid  16  is coupled to shroud  14  using hinge couplings  15   a  and  15   b . Each hinge coupling  15   a  and  15   b  allows lid  16  to pivot with respect to shroud  14  to open the lid. In this embodiment, hinge couplings  15   a  and  15   b  each include a bolt assembly with a bolt  19  (hinge coupling  15   a  includes bolt  19   a  and hinge coupling  15   b  includes bolt  19   b ). Each bolt  19  passes through recesses formed in lid  16  and shroud  14  to secure the lid to the shroud and to provide the ability of the lid to pivot with respect to the shroud. However, couplings in other embodiments may include any suitable fasteners or other components to aid in coupling a shroud assembly lid to the shroud. Such components may include, for example, screws or any other suitable fastening component. Moreover, hinge couplings in other embodiments may not include one or more of the illustrated components of hinge couplings  15 . While the illustrated embodiment includes two hinge couplings approximately 180 degrees apart at a generally circular lid, other embodiments may include any number of couplings at any suitable position to secure a shroud assembly lid to the shroud.  
         [0023]     The use of more than one hinge coupling in particular embodiments allows a user to open lid  16  from either coupling. For example, if a user desired to open lid  16  to access components of tank  26 , the user may remove bolt  19   a  from hinge coupling  15   a  or bolt  19   b  from hinge coupling  15   b . If the user removed bolt  19   a  from hinge coupling  15   a , the user may then lift lid  16  proximate to hinge coupling  15   a  such that the lid pivots at hinge coupling  15   b  which keeps the lid fastened to the shroud. Similarly, if the user removed bolt  19   b  from hinge coupling  15   b , the user may then lift lid  16  proximate to hinge coupling  15   b  such that the lid pivots at hinge coupling  15   a  which keeps the lid fastened to the shroud. A user may choose to open the lid at a particular hinge coupling based on any of a number of factors. For example, in one situation one coupling may be more accessible than the other.  
         [0024]     Lid  16  includes a relief valve hole  22  which aligns with a relief valve  32  of riser  30  when lid  16  is positioned upon shroud  14 . In particular embodiments, lid  16  may comprise a diameter ranging from approximately sixteen to twenty-one inches, such as 19⅛ inches.  
         [0025]      FIG. 2  illustrates the shroud assembly of  FIG. 1  with lid  16  in an open position, in accordance with a particular embodiment of the present invention. As illustrated, lid  16  is in an open position with hinge coupling  15   b  still secured to provide pivoting movement of the lid with respect to shroud  14 . Thus, a user may have removed bolt  19   a  of hinge coupling  15   a  in order to open the lid. In the illustrated embodiment, lid  16  is open in an approximately 90 degree-position with respect to shroud  14 . Hinge couplings in particular embodiments may include stops, other components or suitable shapes or configurations to restrict the movement of lid  16  with respect to shroud  14  when lid  16  is opened by a user. For example, in some embodiments such movement may be restricted to an amount less than or greater than 90 degrees.  
         [0026]      FIG. 3  is an exploded view illustrating hinge coupling  15   a  of the shroud assembly of  FIG. 1 , in accordance with a particular embodiment of the present invention. Hinge coupling  15   a  includes bolt  19   a , nut  27  and washers  25 . In the illustrated embodiment, shroud  14  includes protrusions  21   a  and  21   b , each with a recess through which bolt  19   a  passes. Lid  16  includes a protrusion  23  positioned between protrusions  21   a  and  21   b  of shroud  14  when the lid is secured to shroud  14 . Bolt  19   a  also passes through a recess of protrusion  23  when the lid is secured to the shroud. When lid  16  is opened, protrusion  23  of lid  16  rotates with respect to protrusions  21   a  and  21   b . In some cases, lid  16  may rotate with respect to bolt  19   a , while in other cases the bolt may rotate with lid  16  such that the bolt rotates within the recesses of protrusions  21   a  and  21   b.    
         [0027]     In particular embodiments, hinge couplings  15   a  and  15   b  may have different configurations such that lid  16  will fit on shroud  14  in only one way. For example, one hinge coupling may have a protrusion  23  with a different width than the protrusion  23  of the other hinge coupling. In this example, each hinge coupling&#39;s protrusions  21   a  and  21   b  will be appropriately spaced apart to correspond to the width of their respective protrusion  23 . Allowing the lid to fit on the shroud in only one way ensures that opening  22  is positioned above valve  32  when the lid is in place.  
         [0028]     As indicated above, it should be understood that other embodiments may include other types of couplings utilizing any other suitable components or shapes or configurations to secure a shroud assembly lid to the shroud.  
         [0029]      FIG. 4  is a cross-sectional view of shroud  14  taken along line  4 - 4  of  FIG. 1 . As illustrated, shroud  14  has a general conical shape. As discussed above, brackets  34  coupled to body  28  of the underground tank slide into slots  20  of shroud  14  to aid in preventing rotation of the shroud while underground.  
         [0030]      FIG. 5  illustrates a shroud assembly  112  for use with an underground tank  126 , in accordance with another embodiment of the present invention. When underground tank  126  is positioned beneath the earth&#39;s surface, shroud assembly  112  is positioned to circumferentially enclose a riser  130  of underground tank  126 . Shroud assembly  112  comprises a shroud  114  and a lid  116 . In particular embodiments, shroud  114  and lid  116  may comprise a plastic material, such as polyurethane or polyethylene, and shroud  114  may be manufactured using a rotary mold method. In some embodiments, shroud  114  and lid  116  may substantially or completely comprise a plastic material. In particular embodiments, shroud  114  and lid  116  may not comprise any metallic material. In the illustrated embodiment, the side of shroud  114  is tapered such that the shroud comprises a generally conical shape. Shrouds in accordance with other embodiments may however comprise other shapes or configurations.  
         [0031]     Underground tank  126  comprises a body  128  for storage and a riser  130  extending generally vertical towards the earth&#39;s surface when the tank is installed underground. In particular embodiments, riser  130  may have a length ranging from fourteen to twenty-eight inches. Body  128  and riser  130  of underground tank  126  comprise carbon steel; however in other embodiments components of underground tanks may comprise other compositions. Underground tank  126  includes a withdrawal valve  131  for withdrawal of the stored composition, such as LPG. The top of riser  130  may include a plurality of valves, such as a relief valve  132 . Particular embodiments include a service valve at the top of riser  130  serving several purposes, including a service opening to which a gas line may be connected.  
         [0032]     A bottom edge  117  of shroud  114  is shaped to conform to a convex surface of body  128  of tank  126 . Shroud  114  includes a cutout portion  118  at its base to provide a recess through which a gas line may pass for connection with withdrawal valve  131  of tank  126 . Shroud  114  also includes slots  120  through which brackets  134  of underground tank  126  may slide during installation of shroud  114 . The positioning of brackets  134  within slots  120  prevents rotation or other movement of the shroud while underground. Other embodiments may include other components to hold shroud  114  in place around riser  130  of tank  126 .  
         [0033]     Lid  116  of shroud assembly  112  comprises a general circular shape in the illustrated embodiment. Lid  116  may be rotated when placed upon shroud  114  in order to lock lid  116  into place, as further discussed below. Lid  116  includes a relief valve hole  122  which aligns with a relief valve  132  of riser  130  when lid  116  is positioned upon shroud  114 . Lid  116  also includes two twist holes  124  through which a user may insert tools or his fingers in order to twist and remove lid  116  off of shroud  114 . Other embodiments may include another number of twist holes or may utilize another mechanism to aid in placement and removal of lid  16  with respect to shroud  114 .  
         [0034]      FIG. 6  illustrates the underside of lid  116  of shroud assembly  112  of  FIG. 5 , in accordance with a particular embodiment. The underside of lid  116  includes an extended portion  135  and an overhang portion  137 . Lid  116  includes lugs  144  protruding from extended portion  135 . Lugs  144  aid in locking lid  116  into place upon the shroud as further discussed below.  
         [0035]      FIG. 7A  is an exploded view illustrating lid  116  and shroud  114  of  FIG. 5 , in accordance with a particular embodiment of the present invention. When lid  116  is twisted into position upon shroud  114 , a bottom surface of overhang portion  137  rests upon a top rim surface  140  of a rim portion  141  of shroud  114 . In such position, an inside rim surface  142  of shroud  114  surrounds extended portion  135  of lid  116 .  
         [0036]     Rim portion  141  of shroud  114  includes lug slots  146  through which lugs  144  may be vertically inserted when lid  116  is placed upon shroud  114 . Lid  116  may then be rotated (e.g., in a clockwise direction in the illustrated embodiment) so that lugs  144  of lid  116  slide within lug slots  146  such that rim portion  141  of shroud  114  prevents vertical removal of lid  116 . Lid  116  must be rotated in an opposite direction (e.g., in a counter-clockwise direction in the illustrated embodiment) before lugs  144  may vertically slide out of lug slots  146  in order to remove lid  116  from shroud  114 . While lugs  144  and a top portion of lug slots  146  have a general rectangular configuration in this embodiment, it should be understood that other embodiments may include lugs and/or lug slots having other shapes or configurations. Moreover, shroud assemblies in accordance with other embodiments may include other mechanisms for locking the lid into place on the shroud.  
         [0037]      FIG. 7B  is an exploded view further illustrating a lug slot  146  of the shroud lid of  FIG. 7A , in accordance with a particular embodiment. As discussed above, shroud lids of other embodiments may include lug slots having other shapes or configurations.  
         [0038]     Although the present invention has been described in detail with reference to particular embodiments, it should be understood that various other changes, substitutions, and alterations may be made hereto without departing from the spirit and scope of the present invention. The present invention contemplates great flexibility in the configuration of a shroud assembly for use with an underground tank.  
         [0039]     Numerous changes, substitutions, variations, alterations and modifications may be ascertained by those skilled in the art and it is intended that the present invention encompass all such changes, substitutions, variations, alterations and modifications as falling within the spirit and scope of the appended claims. Moreover, the present invention is not intended to be limited in any way by any statement in the specification that is not otherwise reflected in the claims.