Secondary containment leak prevention and detection system and method

• US 20050145015A1
• Filed: 03/03/2005
• Published: 07/07/2005
• Est. Priority Date: 09/10/2002
• Status: Abandoned Application

• Current Assignee: Gilbarco Incorporated (Vontier Corp.)
• Original Assignee: Gilbarco Incorporated (Vontier Corp.)
• Inventors: Reid, Kent D., Hutchinson, Ray J., Hart, Robert P., Lucas, Richard K., Dolson, Richard G., Halla, Donald D.
• Application Number:
  US11/070,938
• Publication Number:
  US 20050145015A1
• Time in Patent Office: Days
• US Class Current: 73/40.50R
• CPC Class Codes: B65D 88/76 for use underground manholes, inspection openings, covers therefor B65D90/105; special vessels for collecting or storing rain-water for use in the household E03B3/03; cesspools E03F11/00
• CPC Class Codes: B67D 7/3209 relating to spillage or leakage, e.g. spill containments, leak detection leak detectors for underground fuel dispensing systems G01M3/2892
• CPC Class Codes: B67D 7/66 of rotary type
• CPC Class Codes: B67D 7/78 Arrangements of storage tanks, reservoirs or pipe-lines

Abstract

A pump housing that contains a pump that draws fuel from an underground storage tank containing fuel to deliver to fuel dispensers in a service station environment. The pump is coupled to a double-walled fuel pipe that carries the fuel from the pump to the fuel dispensers. The double-walled fuel piping contains an inner annular space that carries the fuel and an outer annular space that captures any leaked fuel from the inner annular space. The outer annular space is maintained through the fuel piping from the pump to the fuel dispensers so that the outer annular space can be pressurized by a pump to determine if a leak exists in the outer annular space or so that fuel leaked from the inner annular space can be captured by a leak containment chamber in the pump housing.

Claims

1-20. -20. (canceled)

21. A system for detecting a leak in a double-walled fuel piping having an outer annular space that carries fuel from an underground storage tank in a service station environment, comprising:

a sensing unit, comprising;

a vacuum tubing that is coupled to the outer annular space;

a pressure sensor that is coupled to the vacuum tubing to detect the vacuum level in the outer annular space; and

a sensing unit controller that is coupled to the pressure sensor to determine the vacuum level in the outer annular space; and

a submersible turbine pump that is fluidly coupled to the fuel in the underground storage tank to draw the fuel out of the underground storage tank wherein the submersible turbine pump is also coupled to the vacuum tubing, wherein the submersible turbine pump creates a vacuum level in the vacuum tubing to create a vacuum level in the outer annular space wherein the sensing unit controller determines the vacuum level in the outer annular space using the pressure sensor, wherein the tank monitor is electrically coupled to the sensing unit controller to receive the vacuum level in the outer annular space;

a liquid detection sensor that is coupled to the outer annular space, wherein the liquid detection sensor is coupled to the sensing unit controller and wherein the liquid detection sensor detects if liquid is present in the outer annular space; and

wherein the tank monitor indicates a pass condition to a functional liquid leak detection test when liquid is placed on the liquid detection sensor and the liquid detection sensor detects liquid.

22-29. -29. (canceled)

30. A system for conducting a liquid leak detection test for a double-walled fuel piping having an outer annular space that carries fuel from an underground storage tank in a service station environment, comprising:

a sensing unit, comprising;

a vacuum tubing that is coupled to the outer annular space;

a pressure sensor that is coupled to the vacuum tubing to detect the vacuum level in the outer annular space; and

a sensing unit controller that is coupled to the pressure sensor to determine the vacuum level in the outer annular space; and

a liquid detection sensor communicatively coupled to the sensing unit and fluidly coupled to the outer annular space wherein the liquid detection sensor detects if liquid is present in the outer annular space and communicates the presence to the sensing unit;

a submersible turbine pump that is fluidly coupled to the fuel in the underground storage tank to draw the fuel out of the underground storage tank wherein the submersible turbine pump is also coupled to the vacuum tubing, wherein the submersible turbine pump creates a vacuum level in the vacuum tubing to create a vacuum level in the outer annular space and wherein the sensing unit controller monitors the vacuum level in the outer annular space; and

a controller coupled to the sensing unit wherein the controller indicates that the functional liquid leak detection test passed when liquid is placed on the liquid detection sensor and the controller receives a liquid leak detection communication from the sensing unit.

31. The system of claim 30, further comprising a drain valve coupled to the outer annular space to drain any leaked fuel out of the outer annular space.

32. The system of claim 30, wherein the controller communicates the indication of the functional liquid leak detection test to a system comprised from the group consisting of a site controller and a remote system.

33-50. -50. (canceled)

51. A method for conducting a functional vacuum leak test for a double-walled fuel piping having an outer annular space that carries fuel from an underground storage tank in a service station environment, comprising:

opening a drain valve located in a vacuum tubing fluidly coupled to the outer annular space;

creating a vacuum level in the vacuum tubing using a submersible turbine pump that is also fluidly coupled to the fuel in the underground storage tank to draw the fuel out of the underground storage tank;

sensing the vacuum level in the outer annular space using a pressure sensor;

communicating the vacuum level in the outer annular space to a tank monitor; and

indicating a vacuum leak test pass condition if the vacuum level in the outer annular space falls below a threshold vacuum level.

52. The method claim of 51, wherein said step of indicating further comprises indicating a vacuum leak test pass condition if the vacuum level in the outer annular space falls below a threshold vacuum level within a defined amount of time.