摘要:
A double walled riser sump has an annular space between the two walls. The provision of the annular space provides for monitoring the integrity of the two walls of the sump. The two walls of the sump are preferably separated by a thin film or a distance fabric that allows the passage of fluids, and preferably liquids. The annular space may be in fluid communication with a reservoir holding a monitoring fluid and positioned near the top of the sump to be easily accessible. In some embodiments, a top of the riser sump is also double walled and the top annular space is in fluid communication with the annular space between the vertical walls. If a leak develops in either wall of the sump, a corresponding drop in the fluid level of the reservoir will occur.
摘要:
A double walled riser sump has an annular space between the two walls. The provision of the annular space provides for monitoring the integrity of the two walls of the sump. The two walls of the sump are preferably separated by a thin film or a distance fabric that allows the passage of fluids, and preferably liquids. The annular space may be in fluid communication with a reservoir holding a monitoring fluid and positioned near the top of the sump to be easily accessible. In some embodiments, a top of the riser sump is also double walled and the top annular space is in fluid communication with the annular space between the vertical walls. If a leak develops in either wall of the sump, a corresponding drop in the fluid level of the reservoir will occur.
摘要:
A storage tank includes a dome placed over an open end of a riser and secured to the riser by a fiberglass ring formed over a flanged end of the dome and a portion of the riser that is adjacent to the dome such that the interior of the tank may be pressurized to facilitate leak detection. A fillet of putty or other material that will not adhere or only weakly adhere to the riser and dome is placed over a horizontal surface of the flanged end. This arrangement allows the dome to be removed from the riser by simply grinding away a corner portion of the fiberglass ring at the bottom edge of the dome. The dome may then be reused for other tanks.In another embodiment, a domed cover is formed on an interior of the riser. The domed cover preferably includes a flat outside edge which is permanently attached to the inside wall of the riser. After the tank has been installed and tested, the domed portion is cut away, leaving the flat edge attached to the interior wall of the riser. The flat edge then serves as a flange for supporting a required pump, filter or other device.
摘要:
A method for calculating underground storage tank (UST) buoyancy and buoyancy safety factors defines boundaries of side areas such that the boundaries do not overlap for multiple tank installations. Installation plan information may be input over a medium such as the Internet. The computer calculates the buoyancy and buoyancy safety factor and returns this information to the requesting party over the same medium. This technique allows installers to verify the adequacy of installation plans quickly. Records of the information provided by the installer may be kept so the recipient of the information (typically the UST manufacturer) can reconcile differences between the actual installation and the installation plan in the event of UST flotation. The information may be provided on a paper form supplied by the installer. In preferred embodiments, the calculations are tailored to installation guidelines (often provided by the UST manufacturer), which may specify such parameters as spacing between tanks in multi-tank installations, some or all deadman dimensions, slab dimensions, etc. Preferred embodiments generate a form letter that includes the installation plan information and the results of the buoyancy and/or buoyancy safety factor calculations.
摘要:
A triple-walled underground storage tank is provided with primary, secondary and tertiary walls. Between each two adjacent walls, an annular space is provided. The annular space is continuous throughout, and permits the flow of liquid therein. Monitors may provided separately for each annulus, to detect the formation of leaks, or a lack of containment, in either wall defining the annular space. In one embodiment, the tertiary wall is a smooth cylinder formed about the circumferential ribs of the secondary wall. In the alternative embodiment, the rib-bearing wall is the tertiary wall, and the walls and annular materials of the tank are formed within a female mold. In either case, a tank prepared from integral ribs, with superior robustness and strength, is provided with triple containment.
摘要:
A form suitable for use in an underground storage tank installation includes an upper portion sized and shaped to receive a street box and a lower portion that fits over and surrounds an upper portion of a riser on the tank. In preferred embodiments, the riser acts as a containment sump, a portion of the riser sidewall is double walled, and the bottom of the lower portion of the form extends to a depth below the top of the double walled portion of the riser. Preferably, the cross sectional shape of the form is circular and the bottom of the riser's lower portion is outwardly flanged, which serves to support the form during installation operations. The form has a stepped structure, with the upper portion of the form having a smaller circumference than the lower portion and a transition between the upper and lower portions forming the step.
摘要:
A retaining system in which straps are provided with hooks that remain engaged with retaining loops even when tension on the straps is released and in which the tightening mechanism includes rods which are located partially below a rib surface on which the straps are placed such that the ends of the rods are near the plane of the strap ends, thereby greatly reducing the bending moment applied to the strap ends and threaded rods. The hook preferably includes a cavity opposite the hook end that will engage the retaining loop when no tension is on the line. In some embodiments, the hook includes a spring-loaded retaining clip to further ensure that the hook does not become disengaged from the retaining loop. The tightening mechanism includes two rods, each of which is positioned to one side of a rib on which the straps rest.
摘要:
A triple-walled underground storage tank is provided with primary, secondary and tertiary walls. Between each two adjacent walls, an annular space is provided. The annular space is continuous throughout, and permits the flow of liquid therein. Monitors may be provided separately for each annulus, to detect the formation of leaks, or a lack of containment, in either wall defining the annular space. In one embodiment, the tertiary wall is a smooth cylinder formed about the circumferential ribs of the secondary wall. In the alternative embodiment, the rib-bearing wall is the tertiary wall, and the walls and annular materials of the tank are formed within a female mold. In either case, a tank prepared from integral ribs, with superior robustness and strength, is provided with triple containment.
摘要:
A wet well apparatus, and installation method therefore, that includes a cylindrical body extending between a first end and a second end along a body axis defining an interior material holding volume and a base form closing the first end of the cylindrical body to define a base interior volume adjacent the interior material holding volume of the cylindrical body. The base form is configured to receive a flowable fill material in the base interior volume.
摘要:
A form suitable for use in an underground storage tank installation includes an upper portion sized and shaped to receive a street box and a lower portion that fits over and surrounds an upper portion of a riser on the tank. In preferred embodiments, the riser acts as a containment sump, a portion of the riser sidewall is double walled, and the bottom of the lower portion of the form extends to a depth below the top of the double walled portion of the riser. Preferably, the cross sectional shape of the form is circular and the bottom of the riser's lower portion is outwardly flanged, which serves to support the form during installation operations. The form has a stepped structure, with the upper portion of the form having a smaller circumference than the lower portion and a transition between the upper and lower portions forming the step.