Patent · US Expired

Female-molded underground storage tank and method of making

US5720404A · kind A · utility

9Cited by
8References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 1996
Grant dateFeb 24, 1998
Priority date
Expiry dateAug 30, 2016

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29L2031/712
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A female-molded double-walled underground storage tank is provided with an annulus of reduced thickness, defined by a plastic film. The film separates the inner and outer walls of the tank, providing an annulus which can be monitored to monitor the tank for failure of either the inner or the outer tank, before contamination of the exterior environment. The tank is formed of fiberglass reinforced plastic, the inner and outer walls thereof being tied together by fiberglass reinforced plastic which holds the annular film in place. The domes of the outer and inner shell are separated due to a layer of wax and alcohol applied to the inner surface of the dome of the exterior tank prior to formation of the interior tank. The spaces between the flats of the two tanks, the domes of the two tanks, and the interior of the ribs of the exterior tank are placed in fluid communication by gutters running along the length of the tank.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.