Abstract: A submersible turbine pump includes a power head enclosed in a casing. A vacuum source associated with the submersible turbine pump draws a vacuum in the interior space of the casing. A pressure sensor may be used to monitor the vacuum in the interior space to detect a leak in the power head or the casing. If a leak is detected, an alarm may be generated and the submersible turbine pump may be deactivated.

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.

Abstract: A submersible turbine pump includes a power head enclosed in a casing. A vacuum source associated with the submersible turbine pump draws a vacuum in the interior space of the casing. A pressure sensor may be used to monitor the vacuum in the interior space to detect a leak in the power head or the casing. If a leak is detected, an alarm may be generated and the submersible turbine pump may be deactivated.

Abstract: A pump housing contains a pump that draws fuel from an underground storage tank to deliver fuel to fuel dispensers in a service station environment. The pump is coupled to a double-walled riser pipe that carries the fuel from the underground storage tank to the pump. The double-walled fuel piping contains an inner space that carries the fuel and an outer annular space that captures any leaked fuel from the inner space. The outer annular space is coupled to a vacuum created by the pump to determine if a leak exists in the outer annular space. An alternate submersible turbine pump has a double-walled housing with a pressure sensor disposed in the interstitial space of the double-walled housing. A vacuum may be created therein to determine if leaks are present in the housing of the submersible turbine pump.

Abstract: A vacuum generator that is coupled to a double-walled fuel supply piping internal to a fuel dispenser that carries the fuel from the underground storage tank to the hose and nozzle of the fuel dispenser. The double-walled fuel supply piping contains an inner piping that carries the fuel. An interstitial space is formed by the space between the inner piping and an outer piping that surrounds the inner piping to capture any leaked fuel from the inner piping. The interstitial space is coupled to a vacuum created by the vacuum generator to determine if a leak exists in the interstitial space. The vacuum generator may be a standalone unit or may be a submersible turbine pump that also pumps fuel from the underground storage tank to the fuel dispenser.

Abstract: A submersible turbine pump includes a power head enclosed in a casing. A vacuum source associated with the submersible turbine pump draws a vacuum in the interior space of the casing. A pressure sensor may be used to monitor the vacuum in the interior space to detect a leak in the power head or the casing. If a leak is detected, an alarm may be generated and the submersible turbine pump may be deactivated.

Abstract: Determining a maximum dispensing efficiency of a dispensing point in a fuel dispenser and determining if a dispensing point has a blockage and/or a performance problem if the maximum dispensing efficiency is less than expected. The maximum dispensing efficiency is calculated by determining the dispensing events exhibiting the lowest time for dispensed volume from a set of volume and time pair measurements for the dispensing point. The dispensing events exhibiting the lowest time for dispensed volume that are used to determine the maximum dispensing efficiency are taken from dispensing events where the amount of dead time, the time between the activation of a fuel dispensing event and the engaging of a nozzle and the time between the disengaging of the nozzle and the deactivation of the dispensing event, and customer or pre-pay transaction controlled reduced flow rates are minimized.

Abstract: A method and apparatus for monitoring and determining fuel vapor recovery performance. The dispensing of liquid fuel into a tank by a gas pump nozzle displaces a mixture of air and fuel ullage vapor in the tank. These displaced vapors may be recovered at the dispensing point nozzle by a vapor recovery system. A properly functioning vapor recovery system recovers approximately one unit volume of vapor for every unit volume of dispensed liquid fuel. The ratio of recovered vapor to dispensed fuel is termed the A/L ratio, which should ideally be approximately equal to one (1). The A/L ratio, and thus the proper functioning of the vapor recovery system, may be determined by measuring liquid fuel flow and return vapor flow using a vapor flow sensor on a nozzle-by-nozzle basis. The determination of A/L ratios for individual nozzles are calculated using a reduced number of vapor flow sensors.

Abstract: A method and apparatus for monitoring and determining fuel vapor recovery performance is disclosed. The dispensing of liquid fuel into a tank by a conventional gas pump nozzle naturally displaces a mixture of air and fuel ullage vapor in the tank. These displaced vapors may be recovered at the dispensing point nozzle by a vapor recovery system. A properly functioning vapor recovery system recovers approximately one unit volume of vapor for every unit volume of dispensed liquid fuel. The ratio of recovered vapor to dispensed fuel is termed the A/L ratio, which should ideally be approximately equal to one (1). The A/L ratio, and thus the proper functioning of the vapor recovery system, may be determined by measuring liquid fuel flow and return vapor flow (using a vapor flow sensor) on a nozzle-by-nozzle basis. The disclosed methods and apparatus provide for the determination of A/L ratios for individual nozzles using a reduced number of vapor flow sensors.

Abstract: A method and apparatus for monitoring a fuel vapor recovery system to determine if a leak condition exists in either the vapor return passage in a fuel dispenser or a common vapor return pipe. An air-flow sensor (AFS) may be located in the common vapor return pipe for all of the dispensing points at a service station, or in each fuel dispenser and coupled to the dispensing points of the fuel dispenser. The AFS registers vapor flow recovered by a dispensing point(s) that is returned back to the storage tank. If the AFS measures vapor flow when such dispensing point(s) coupled to such AFS is not actively recovering vapor, this is indicative of a leak in such dispensing point(s). The leak condition is reported by a tank monitor or other reporting system so that appropriate measures can be taken.

Abstract: A method and apparatus for monitoring and determining fuel vapor recovery performance is disclosed. The dispensing of liquid fuel into a tank by a conventional gas pump nozzle naturally displaces a mixture of air and fuel ullage vapor in the tank. These displaced vapors may be recovered at the dispensing point nozzle by a vapor recovery system. A properly functioning vapor recovery system recovers approximately one unit volume of vapor for every unit volume of dispensed liquid fuel. The ratio of recovered vapor to dispensed fuel is termed the A/L ratio, which should ideally be approximately equal to one (1). The A/L ratio, and thus the proper functioning of the vapor recovery system, may be determined by measuring liquid fuel flow and return vapor flow (using a vapor flow sensor) on a nozzle-by-nozzle basis. The disclosed methods and apparatus provide for the determination of A/L ratios for individual nozzles using a reduced number of vapor flow sensors.

Abstract: A system and method for removing, compressing, and storing excess air and vapors from a fuel dispensing facility fuel storage containment system during periods of over-pressurization without venting or processing the excess air and vapors. The stored air and vapors are subsequently returned back to the containment system during periods of under-pressurization that typically occur diurnally during periods of high fueling activity. The system may be used to compliment an ORVR compatible dispensing system that typically encounters over-pressurization problems when low or no refueling activity is occurring.

Abstract: A submersible turbine pump includes a power head enclosed in a casing. A vacuum source associated with the submersible turbine pump draws a vacuum in the interior space of the casing. A pressure sensor may be used to monitor the vacuum in the interior space to detect a leak in the power head or the casing. If a leak is detected, an alarm may be generated and the submersible turbine pump may be deactivated.

Abstract: A vacuum generator that is coupled to a double-walled fuel supply piping internal to a fuel dispenser that carries the fuel from the underground storage tank to the hose and nozzle of the fuel dispenser. The double-walled fuel supply piping contains an inner piping that carries the fuel. An interstitial space is formed by the space between the inner piping and an outer piping that surrounds the inner piping to capture any leaked fuel from the inner piping. The interstitial space is coupled to a vacuum created by the vacuum generator to determine if a leak exists in the interstitial space. The vacuum generator may be a standalone unit or may be a submersible turbine pump that also pumps fuel from the underground storage tank to the fuel dispenser.

Abstract: A storage tank leak detection and prevention system that detects a breach or leak in the interstitial space of a double-walled fuel storage tank in a service station environment. The interstitial space is placed under a vacuum using a submersible turbine pump that is also used to pump fuel to the fuel dispensers in the service station and therefore a separate vacuum generating source is not required. A sensing unit and/or tank monitor monitors the vacuum level in the interstitial space over time. If a significant vacuum level change occurs in the interstitial space after the interstitial space is placed under a vacuum level, a catastrophic leak detection alarm is generated. If a minor vacuum level change occurs in the interstitial space after the interstitial space is placed under a vacuum, a precision leak detection alarm is generated. Functional tests also ensure that the leak detection system is functioning properly.

Abstract: A method and apparatus for monitoring and determining fuel vapor recovery performance is disclosed. The dispensing of liquid fuel into a tank by a conventional gas pump nozzle naturally displaces a mixture of air and fuel ullage vapor in the tank. These displaced vapors may be recovered at the dispensing point nozzle by a vapor recovery system. A properly functioning vapor recovery system recovers approximately one unit volume of vapor for every unit volume of dispensed liquid fuel. The ratio of recovered vapor to dispensed fuel is termed the A/L ratio, which should ideally be approximately equal to one (1). The A/L ratio, and thus the proper functioning of the vapor recovery system, may be determined by measuring liquid fuel flow and return vapor flow (using a vapor flow sensor) on a nozzle-by-nozzle basis. The disclosed methods and apparatus provide for the determination of A/L ratios for individual nozzles using a reduced number of vapor flow sensors.

Abstract: A method and apparatus for monitoring and determining fuel vapor recovery performance is disclosed. The dispensing of liquid fuel into a tank by a conventional gas pump nozzle naturally displaces a mixture of air and fuel ullage vapor in the tank. These displaced vapors may be recovered at the dispensing point nozzle by a vapor recovery system. A properly functioning vapor recovery system recovers approximately one unit volume of vapor for every unit volume of dispensed liquid fuel. The ratio of recovered vapor to dispensed fuel is termed the A/L ratio, which should ideally be approximately equal to one (1). The A/L ratio, and thus the proper functioning of the vapor recovery system, may be determined by measuring liquid fuel flow and return vapor flow (using a vapor flow sensor) on a nozzle-by-nozzle basis. The disclosed methods and apparatus provide for the determination of A/L ratios for individual nozzles using a reduced number of vapor flow sensors.

Abstract: A storage tank leak detection and prevention system that detects a breach or leak in the interstitial space of a double-walled fuel storage tank in a service station environment. The interstitial space is placed under a vacuum using a submersible turbine pump that is also used to pump fuel to the fuel dispensers in the service station and therefore a separate vacuum generating source is not required. A sensing unit and/or tank monitor monitors the vacuum level in the interstitial space over time. If a significant vacuum level change occurs in the interstitial space after the interstitial space is placed under a vacuum level, a catastrophic leak detection alarm is generated. If a minor vacuum level change occurs in the interstitial space after the interstitial space is placed under a vacuum, a precision leak detection alarm is generated. Functional tests also ensure that the leak detection system is functioning properly.

Abstract: A method and apparatus for monitoring and determining fuel vapor recovery performance is disclosed. The dispensing of liquid fuel into a tank by a conventional gas pump nozzle naturally displaces a mixture of air and fuel ullage vapor in the tank. These displaced vapors may be recovered at the dispensing point nozzle by a vapor recovery system. A properly functioning vapor recovery system recovers approximately one unit volume of vapor for every unit volume of dispensed liquid fuel. The ratio of recovered vapor to dispensed fuel is termed the A/L ratio, which should ideally be approximately equal to one (1). The A/L ratio, and thus the proper functioning of the vapor recovery system, may be determined by measuring liquid fuel flow and return vapor flow (using a vapor flow sensor) on a nozzle-by-nozzle basis. The disclosed methods and apparatus provide for the determination of A/L ratios for individual nozzles using a reduced number of vapor flow sensors.

Abstract: A pump housing contains a pump that draws fuel from an underground storage tank to deliver fuel to fuel dispensers in a service station environment. The pump is coupled to a double-walled riser pipe that carries the fuel from the underground storage tank to the pump. The double-walled fuel piping contains an inner space that carries the fuel and an outer annular space that captures any leaked fuel from the inner space. The outer annular space is coupled to a vacuum created by the pump to determine if a leak exists in the outer annular space. An alternate submersible turbine pump has a double-walled housing with a pressure sensor disposed in the interstitial space of the double-walled housing. A vacuum may be created therein to determine if leaks are present in the housing of the submersible turbine pump.