Abstract: The present invention is directed to a retrofit underground storage tank (30) and method for making the same. A portion of an underground primary tank (32) its uncovered and an access opening (42) in formed therein. A plurality of trifolds (50, 120, 122, and 124) comprising three folded up and banded together panels (52, 54, 56) which are jointed together by hinges are inserted into the primary tank. A monorail or conveyor (90) is inserted into and suspended from above the primary tank (32). Trolleys (102, 104) on the monorail (90) assist in transporting the trifolds (50, 120, 122 and 124) within the primary tank (32) and then the monorail (90) is removed. Trifolds (50, 120, 122 and 124) are unbanded and unfolded and are arranged circumferentially about the tank. Jack stands are used to hold panels of the trifolds in place.

Abstract: The present invention is directed to a retrofit underground storage tank (30) and method for making the same. A portion of an underground primary tank (32) its uncovered and an access opening (42) in formed therein. A plurality of trifolds (50, 120, 122, and 124) comprising three folded up and banded together panels (52, 54, 56) which are jointed together by hinges are inserted into the primary tank. A monorail or conveyor (90) is inserted into and suspended from above the primary tank (32). Trolleys (102, 104) on the monorail (90) assist in transporting the trifolds (50, 120, 122 and 124) within the primary tank (32) and then the monorail (90) is removed. Trifolds (50, 120, 122 and 124) are unbanded and unfolded and are arranged circumferentially about the tank. Jack stands are used to hold panels of the trifolds in place.

Abstract: An apparatus for tightening strap members comprises a buckle member having a first means for attachment to a strap and a second means for attachment to a strap. A plurality of longitudinally spaced apart pin-receiving boreholes are provided on slidably related sections of the buckle member such that the boreholes in one section have a vernier relationship with the boreholes in another section, thus permitting a boreholes to come into alignment as the sections are slid past each other at an adjustment increment which is less than the spacing between the boreholes on either section. A method is also provided for using the assembly to tightening a strap.

Abstract: A double-walled fiberglass reinforced resin underground storage tank including a generally cylindrical inner wall having a plurality of circumferential support ribs bonded thereto, at least one spacer filament mounted on the outer surface of the inner wall of the tank over a substantial portion of the length of the tank, and an outer wall substantially conforming to the contour of the inner wall and the support ribs but not adhered to the inner wall or the support ribs. The outer wall cures into relatively tight conformance with the inner wall and support ribs resulting in a reduced annular space between the walls. Small voids are created immediately adjacent to the spacer filaments, providing fluid passageways which enhance the otherwise slow migration of fluid in the annular space.