The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 27, 1999
Filed:
Aug. 22, 1997
Ronald Marshall Bass, Houston, TX (US);
James Donald Haupt, Houston, TX (US);
Timothy Caywood Hurley, Katy, TX (US);
Richard Allen Littlefield, Sealy, TX (US);
Paul Alfred Westbrook, Richmond, TX (US);
Shell Oil Company, Houston, TX (US);
Abstract
The invention comprises a tool which can be inserted through the fill nozzle of an underground fuel storage tank to measure the tank wall thickness. The invention, in a preferred embodiment, uses ultrasonic thickness measurement technology, a well known inspection technique. A special type of ultrasonic probe known as a ZIP (Zero Interface Probe) is required to measure the thickness of fiberglass. A thickness measurement is accomplished by pressing the tool transducers firmly against the inside surface of the fiberglass tank after applying a couplant gel to the surface of the transducers. The tool is connected to an ultrasonic flaw detector, which generates a transmitted pulse and displays the transmitted and reflected pulses on a display screen. The thickness is determined by measuring the time-of-flight (on the display screen) between appropriate pulses. The time-of-flight is proportional to twice the thickness (since the sound pulse must travel to the back wall and return), the proportionality factor being the speed of sound in the fiberglass (speed.times.time=distance).