JP4174682B2 - Underground tank oil leak detection device - Google Patents

Description

  The present invention relates to an oil leak detection device for an underground tank that detects an oil leak in an underground tank installed on a site of a gas station, for example, in order to supply fuel oil such as gasoline to an automobile.

Generally, in a gasoline filling station, a plurality of underground tanks formed as cylindrical sealed containers are embedded, and fuel oils such as gasoline, light oil, and kerosene are individually stored in these underground tanks. By the way, when a crack or the like occurs in the underground tank, there is a risk that fuel oil, which is a highly flammable combustible material stored in the underground tank, leaks into the surrounding ground, causing danger. Therefore, an oil leakage detection device is installed in the ground around the underground tank as means for detecting the occurrence of oil leakage. For example, the applicant stores a rotating indicator with a balance weight on the upper end side of a gas detector tube buried in the vicinity of an underground tank, and stretches a string made of a material that can be melted with oil attached with a tension weight in the gas detector tube. The wire is linked to the tension weight so as to invert the rotation indicator against the weight of the balance weight by cutting the string, and an electric signal of the reed switch that is turned on by the inversion of the rotation indicator is output to the notification device. The technique regarding the oil leak detection apparatus of an underground tank is proposed (for example, refer patent document 1).
Japanese Patent No. 3074351 (pages 2 and 3, FIGS. 1 to 3).

  Conventional underground tank oil leak detection devices can detect oil leaks with a simple mechanical structure, but when newly installed in an existing underground tank, the detection port on the upper end of the gas detector tube is also obsolete. There is a risk of requiring extensive work such as a major modification, such as a major modification such as removing a gas detector tube that has been buried deep underground, and refilling it.

  The present invention has been made in view of the above circumstances, and can be installed in a short time with a simple operation using a gas detection tube used in an existing oil leakage detection device, so that the oil leakage can be safely and reliably performed. It is an object of the present invention to provide an underground tank oil leakage detection device that can be easily grasped and can be easily maintained.

In order to achieve the above object, in the first aspect of the present invention, the gas detector pipe buried in the ground near the underground tank, the one end side is located at the bottom in the gas detector pipe , and the other end side is A swelling resistance change type leak sensor that expands and changes its electrical resistance when it comes into contact with an oil component that is vertically suspended so as to be positioned at a detection port near the ground surface of the gas detection pipe, and the detection A terminal case having a terminal chamber disposed near the mouth and having a terminal chamber connected to a control device for detecting oil leakage by a signal line through which the other end of the leak sensor is introduced; A terminal cover provided with a protective cover for sealing the upper surface of the terminal chamber , wherein the terminal case is disposed in a groove formed in the ground surface on the side surface near the detection port, and the upper surface is opened and a terminal block is provided therein. And the inspection from both end faces of the terminal chamber. The leakage sensor has an introduction portion extending in a band shape toward the mouth side and an attachment portion for fixing the protective cover with screws, and the upper end portion side of the leak sensor is bent from the detection port toward the terminal case side. A curved portion is formed, and the signal line of the leakage sensor on the curved portion side is guided from the introducing portion to the terminal chamber, connected on the terminal block, and disposed along the groove on the opposite side to the introducing portion. The protection cover is strong enough to protect the leakage sensor and the terminal case even if the upper surface of the protective cover is stepped on by a vehicle wheel or a person, and is safe even if the wheel or person steps on the protective cover. It is characterized by being formed into a curved surface . The gas detector tube used in the existing oil leak detector can be installed in a short time with a simple operation, and the leak sensor can grasp the oil leak safely and securely, and the upper part of the terminal case Maintenance work is also facilitated by removing the protective cover. In addition, by forming the terminal case in the groove on the ground surface, it is possible to protect the equipment against trampling of the vehicle and people and prevent danger to the vehicle and people, and form a curved portion from the detection port to form the terminal case The upper part of the leak sensor introduced into the terminal chamber can be covered, and a safety explosion-proof structure can be realized by hermetically sealing the upper surface of the terminal case with a sealing material.

  In the present invention, the gas detection pipe buried in the ground near the underground tank, and the swelling resistance arranged so that one end side is located in the gas detection pipe and the other end side is located in the detection opening near the ground surface of the gas detection pipe A change-type leak sensor, a terminal case that is arranged near the detection port and has a terminal chamber that is connected to a control device for detecting oil leaks by introducing the other end of the leak sensor, and a leak near the detection port By providing a protective cover that covers the upper part of the sensor and seals the upper surface of the terminal chamber, it can be installed in a short time with a simple operation using the gas detection tube used in the existing oil leakage detection device. This makes it possible to safely and reliably grasp the oil leakage by the leakage sensor, and the maintenance work is facilitated by removing the protective cover at the top of the terminal case.

  Hereinafter, the present invention will be specifically described with reference to an illustrated embodiment. 1-3 is a figure explaining the oil leak detection apparatus of the underground tank of embodiment of this invention, FIG. 1 is a longitudinal cross-sectional view of an oil leak detection apparatus, FIG. 2 is a top view of an oil leak detection apparatus, FIG. FIG. 2 is an overall view illustrating an underground tank device of a gas station.

  FIG. 3 shows the overall structure of the underground tank apparatus 1 provided in the gas station, and an underground tank body 30 for storing any liquid oil such as gasoline, light oil, kerosene, etc. in the underground of the site 2. An oil supply device 31 is erected on the site 2. The upper side of the underground tank body 30 is provided with manhole pits 32, 32 in which the upper surface of the site 2 is made of concrete and manholes are formed on the concrete surface. The underground tank body 30 is provided with an oil supply pipe 33 whose lower end communicates with the inside. The upper end portion side of the oil supply pipe 33 is introduced into a manhole pit 32 at the upper part of the underground tank body 30 and communicated with a pipe having an oil supply port 34 to which an oil supply hose for oil unloaded from the tank truck is connected on the ground. Yes. Further, the underground tank body 30 is provided with an oil supply pipe 35 whose lower end side is communicated with the inside, and the upper end side of the oil supply pipe 35 is communicated with the horizontal draw pipe 36 in the manhole pit 32. The other end side of the horizontal draw pipe 36 is introduced into an oil supply pit 37 formed at the lower portion of the oil supply device 31, led to the upper portion, and communicated with an oil supply mechanism such as a pump of the oil supply device 31. In the manhole pit 32 at the upper part of the underground tank body 30, an underground tank leakage detection device 42 is arranged. Further, in the other manhole pit 32, an elongated stem 43 extends from the upper part to the vicinity of the bottom of the lower underground tank body 30, and the upper end of the stem 43 is a magnetostrictive oil that detects the oil level of the underground tank body 30. An area meter 44 is provided. Further, an oil leakage detection device 45 is disposed in each of the manhole pits 32 and 32 and the oil supply pit 37. In the vicinity of the oil inlet 34, there is provided a ventilation pipe 38 having a lower end portion communicating with an upper space in the underground tank body 30 and an upper end portion opened to the upper space of the site 2. Further, in the vicinity of the underground tank body 30, the oil leakage detection device 10 for detecting the oil leakage of the embodiment of the present invention is provided. In an office or the like away from the underground tank body 30, a control device 40 including a computer device that performs data processing for overall management of the underground tank body 30, a seismic sensor 41 that detects an earthquake shake, and A display 39 for displaying the processing result of the control device 40 is arranged. The detection signal of the leakage detection device 45, the detection signal of the oil leakage detection device 10, and the detection signal of the oil level gauge 44 are connected to be transmitted to the control device 40 through signal lines, respectively, and the earthquake detection by the seismic sensor 41 is performed. The control signal for controlling the opening and closing of the valve is connected so as to be transmitted to the control valve provided on the oil inlet 34 side by a signal line.

As shown in FIGS. 1 and 2 , the oil leakage detection device 10 of the present invention includes a gas detection pipe 11 embedded in the ground near the underground tank 30, and a leakage sensor 13 provided in the gas detection pipe 11. The terminal case 20 for connecting the signal detected by the leak sensor 13 guided from the vicinity of the detection port 12 on the upper end side of the gas detection tube 11 to the control device 40, and the upper surface side of the detection port 12 and the terminal case 20 It comprises a protective cover 15 and the like for covering.

  The gas detection pipe 11 is composed of a bottomed cylindrical body buried in the ground near the underground tank 30 to a depth of about 10 meters from the ground surface, and a plurality of small holes for oil leakage are formed on the peripheral wall. In the vicinity, there is an open detection port 12 made of a metal material or the like. As such a gas detection pipe 11, what was used for the existing underground tank 30 can be used, for example. A leak sensor 13 is vertically suspended from the bottom to the upper part of the detection port 12 in the gas detection tube 11. The leakage sensor 13 is a swelling resistance change type sensor that swells when it comes into contact with the oil component and changes its electrical characteristics. The terminal case 20 is formed in, for example, a box shape required from a safety explosion-proof structure, and is disposed in a groove 28 formed in the vicinity of the detection port 12 on the upper end side of the gas detection tube 11. Such a groove 28 is formed, for example, by removing ground concrete on the side surface of the detection port 12 to a predetermined depth with a cutter or the like. The terminal case 20 includes a terminal chamber 21 having an upper surface opened and a terminal block 23 provided therein, an introduction portion 22 having portions extending from both side end surfaces of the terminal chamber 21 to the detection port 12 side, An attachment portion 29 is provided to fix the protective cover 15 with screws 16. A curved portion 14 that is bent toward the terminal case 20 side is formed on the upper end portion side of the leakage sensor 13 in the vicinity of the detection port 12. The signal line 24 of the leakage sensor 13 at the end of the curved portion 14 is guided from the introduction portion 22 of the terminal case 20 into the terminal chamber 21 through the connection portion 25. The signal line 24 of the leakage sensor 13 guided to the terminal chamber 21 is guided by a conduit 27 arranged along the groove 28 on the side opposite to the introduction portion 22 and enters the terminal chamber 21 via the connection portion 26. The signal line connected to the introduced control device 40 is connected on the terminal block 23. The terminal case 20 is fixed in the groove 28 with concrete or the like after the connection of the signal line 24 is completed. The protective cover 15 is formed in a shape that covers the upper side of the terminal case 20 from the upper side of the detection port 12 in an approximately elliptical shape. The protective cover 15 has a space portion 17 large enough to accommodate the curved portion 14 of the leak sensor 13 on the upper side of the detection port 12, and the opening portion above the terminal chamber 21 is held by the packing 18. It is formed in a shape that can be sealed with an airtight structure. Further, the protective cover 15 has a strength that can protect the leakage sensor 13 and the terminal case 20 even when the upper surface of the protective cover 15 is stepped on by a vehicle wheel or a person, and has a curved surface that is safe even when the wheel or person steps on the protective cover 15. . Further, the protective cover 15 is formed in a concave shape so that the screw 16 can be inserted and fixed to the portion corresponding to the attachment portion 29 from the upper surface side, and the head of the screw 16 does not protrude from the surface.

  In the oil leakage detection device 10 having the above configuration, a swelling resistance change type leakage sensor 13 is vertically suspended from the bottom to the top of the detection port 12 in the gas detection tube 11, and the ground surface on the side surface of the detection port 12 is removed. A groove 28 is formed, and a terminal case 20 having a terminal chamber 21 having an upper surface opened in the groove 28 is provided. A curved portion 14 is formed on the upper end side of the leakage sensor 13 and introduced into the terminal chamber 21. 23 is connected to a signal line connected to the control device 40, the upper side of the terminal case 20 is covered with the protective cover 15 from the upper side of the detection port 12, and the opening portion at the upper part of the terminal chamber 21 is sealed with a packing 18. It is sealed. The oil leakage detection signal detected by the leakage sensor 13 is transmitted to the control device 40 via the signal line, and the processing result is displayed on the display 39. Since the leakage sensor 13 is vertically suspended, even the gas detection pipe 11 used in the existing underground tank 30 can be used without requiring a significant modification of the detection opening 12, and the detection opening. 12 A terminal case 20 having a terminal chamber 21 is provided in a groove 28 formed on the ground surface on the side surface side, introduced into the terminal chamber 21 on the upper end side of the leakage sensor 13, and a signal connected to the control device 40 by the terminal block 23 Since it is connected to a wire, it can be installed in a short time with a simple operation. Further, the protective cover 15 covers the upper side of the terminal case 20 from the upper side of the detection port 12 in an elliptical shape, and the opening portion of the upper part of the terminal chamber 21 is held by the packing 18 so as to be sealed with an airtight structure. The structure can be realized, and the upper surface side can protect the leak sensor 13 and the terminal case 20 even if the wheel or person steps on the vehicle, and can be safe and prevent danger even if the wheel or person steps.

  In said embodiment, the shape and magnitude | size of the terminal case 20 and the protective cover 15 can be made arbitrarily, and are not limited to embodiment.

  The present invention can be used for an oil leak detection device for an underground tank that detects an oil leak of an underground tank installed at a gas station where fuel such as gasoline is supplied to an automobile or the like.

It is a general view explaining the underground tank apparatus of the gas station of this invention embodiment. It is a longitudinal cross-sectional view of the oil leak detection apparatus of embodiment of this invention. It is a top view of the oil leak detection apparatus of this invention embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Underground tank apparatus 2 Site 10 Oil leak detection apparatus 11 Gas detection pipe 12 Detection port 13 Leakage sensor 14 Bending part 15 Protective cover 16 Screw 17 Space part 18 Packing 20 Terminal case 21 Terminal room 22 Introduction part 23 Terminal block 24 Signal line 25 Connection portion 26 Connection portion 27 Conduit tube 28 Groove 29 Mounting portion 30 Underground tank body 31 Lubrication device 32 Manhole pit 33 Lubrication tube 34 Lubrication port 35 Lubrication tube 36 Horizontal draw pipe 37 Lubrication pit 38 Ventilation tube 39 Display device 40 Control device 41 Sense Seismic sensor 42 Leak detection device 43 Stem 44 Oil level gauge 45 Oil leak detection device

Claims (1)

A gas detector pipe buried in the ground near the underground tank, and suspended vertically so that one end is located at the bottom of the gas detector pipe and the other end is located at the detection port near the ground surface of the gas detector pipe And a swelling resistance change type leak sensor that expands and changes its electric resistance when it comes into contact with the arranged oil component, and the other end side of the leak sensor that is arranged in the vicinity of the detection port is introduced to leak oil A terminal case having a terminal chamber connected to a control device for detection with a signal line; and a protective cover that covers an upper part of the leakage sensor near the detection port and seals an upper surface of the terminal chamber , Located in a groove formed on the ground surface on the side surface near the detection port, a terminal chamber having an open top surface and a terminal block inside, and extending from the both end surfaces of the terminal chamber to the detection port side in a strip shape The introduction part and the protective cover The leak sensor is formed with a bent portion whose upper end is bent from the detection port toward the terminal case, and the signal line of the leak sensor on the bent portion side is formed. Is guided from the introduction part into the terminal room, is guided on a conduit that is connected on the terminal block and is disposed along a groove opposite to the introduction part, and the upper surface of the protective cover is a vehicle. Oil leakage detection in underground tanks, which has a strength capable of protecting the leakage sensor and the terminal case even when a wheel or a person steps on, and is formed into a curved surface that is safe even when the wheel or person steps on apparatus.

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