Patent · US Expired

Method for storage tank leak detection having ground water compensation

US4993257A · kind A · utility

7Cited by
4References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 16, 1990
Grant dateFeb 19, 1991
Priority date
Expiry dateFeb 16, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01M3/3245
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method is described for enabling leak detection of an underground storage tank surrounded by a water table. The method begins by sealing a test probe in the tank, the test probe having an elongated substantially hollow core with first and second ends, a housing for receiving the second end of the hollow tube and being vented to the fluid product, a low temperature coefficient medium supported in the substantially hollow core of the elongated tube, and a liquid seal supported in the housing between the medium and the fluid product. The method continues by then establishing and maintaining a pressure equilibrium between the hollow core of the test probe and the head space. An inert gas such as nitrogen is then introduced into the head space to overpressurize the head space by an amount sufficient to reestablish a leak at any break in the storage tank despite presence of the water table surrounding the storage tank. Once the tank contents are stabilized, the precision leak test is performed.

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