Natural gas detection device

Abstract

The natural gas detection device comprises an inner tube, a vortex tube, a gas collection cavity, an outer tube and a gas detector, the vortex tube is arranged, and the characteristic of gas flow can be improved by adopting the vortex tube, so that the influence of Knudsen flow regime (narrow tube low speed) is eliminated; through the characteristic that the vortex tube amplifies the gas flow, the sampling amount of the gas in unit time is increased, so that the detection quality is improved, and the detection error is reduced; meanwhile, methane and macromolecular tetrahydrothiophene are fully mixed under the action of rotary stirring of the vortex tube on the gas, so that the detection quality of the gas detector on the natural gas is improved, and the detection error is further reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of detection equipment, and in particular to a natural gas detection device. Background Art

[0002] In the process of gas supply detection and sampling, the currently used gas detection technology is to introduce the gas source into the filter after filtering, use the flow meter to control to the rated capacity of the detection device suction pump, and then collect and verify the gas composition; the use of the prior art will be affected by objective conditions such as the pre-filter and the flow meter, and there will be errors between the detected value and the actual value. The reason is that the pre-equipment is affected by the Knudsen number fluid factor; the principle is that the gas passes through the capillary at extremely low pressure, and its flow law follows the flow of Knudsen's law. When the low-pressure 2500Pa natural gas flows through the pre-filter or flow regulator, it is equivalent to passing through the capillary. At this time, the amount of small molecule methane passing through will become larger, and the amount of large molecule tetrahydrothiophene passing through the meter will be less, which makes the error of the detection value larger. Summary of the invention

[0003] The purpose of the present invention is to design a natural gas detection device to solve the problems raised by the background technology. To achieve the above purpose, the present invention provides the following technical solution: comprising a vortex tube connected to a natural gas discharge port through an inner tube, a gas collecting chamber connected to the cold end of the vortex tube, and an outer tube connected to the inside of the gas collecting chamber, wherein one end of the outer tube away from the gas collecting chamber is connected to a gas detector, and the hot end of the vortex tube is connected to the atmosphere.

[0004] Furthermore, the gas collecting cavity is fixedly connected to the outer tube, one end of the outer tube is located inside the gas collecting cavity, and an air inlet is provided on the outer tube located inside the gas collecting cavity.

[0005] Furthermore, the inner tube is located inside the outer tube, the upper part of the inner tube simultaneously passes through the outer tube and the top of the gas collecting chamber, one end of the inner tube passing through the top of the gas collecting chamber is connected to the vortex tube, the bottom end of the inner tube passes through the outer tube, and the bottom end of the inner tube is connected to the natural gas release port.

[0006] Furthermore, a damping release port is also provided on the gas collecting cavity.

[0007] Furthermore, the damping release port is connected to an exhaust pipe via a second hose, and the exhaust pipe opens upward.

[0008] Furthermore, the exhaust pipe is installed in the middle of the vortex tube through an elastic clamp.

[0009] Furthermore, the hot end of the vortex tube is connected with a bent pipe, and the opening of the bent pipe faces upward.

[0010] Furthermore, an internal threaded sleeve is provided at the end of the bent pipe, and an external thread threadedly connected to the internal threaded sleeve is provided at the hot end of the vortex tube.

[0011] Furthermore, a sealing gasket is provided between the bottom of the internally threaded sleeve and the end of the hot end of the vortex tube.

[0012] Furthermore, outer walls of the curved pipe, the vortex tube, the gas collecting chamber and related connecting pipes are all wrapped with a thermal insulation layer.

[0013] Furthermore, a fixing plate is provided on the outer wall of the air collecting chamber, and an air pump is fixedly connected to the fixing plate. The air inlet pipe of the air pump is connected to the interior of the air collecting chamber, and the air outlet pipe of the air pump is connected to the atmosphere. A valve is provided on the air inlet pipe, and the air outlet pipe is distributed vertically.

[0014] Furthermore, a three-way pipe is connected to the lower part of the outer tube, one outlet end of the three-way pipe is connected to a gas pressure gauge, and the other outlet of the three-way pipe is connected to a filter, a gas flow meter and the gas detector in sequence through a first hose.

[0015] Furthermore, an adjustable support frame is installed at the bottom of the outer tube.

[0016] Furthermore, the support frame includes a first support block fixedly connected to the bottom of the outer tube, a screw fixedly connected to the bottom of the first support block, an adjustment cylinder threadedly connected to the screw, and a second support block rotatably connected to the upper part of the adjustment cylinder, the first support block is rotatably connected to a support foot, the middle part of the support foot is rotatably connected to a drive rod, and the end of the drive rod away from the support foot is rotatably connected to the second support block.

[0017] Furthermore, the cross-section of the supporting foot is a U-shaped groove, one end of the driving rod is located inside the U-shaped groove, and the first supporting block and the second supporting block are both provided with notches, and one end of the driving rod and the supporting foot are both located in the notches.

[0018] Furthermore, a stopper is provided at the top of the screw.

[0019] Furthermore, a support plate is fixedly connected to the middle portion of the outer tube via a fixing tube, and a baffle is fixedly connected to the edge of the support plate.

[0020] Furthermore, the support plate is provided with a plurality of notches.

[0021] Furthermore, a rotating plate is rotatably connected to the fixed cylinder, and an edge of the rotating plate is buckled on the outer wall of the baffle.

[0022] Compared with the prior art, the present invention has the following beneficial effects: the present invention is provided with a vortex tube, which can improve the characteristics of gas flow rate and eliminate the influence of "Knudsen flow state" (narrow tube and low speed); that is, through the characteristic of gas flow amplification of the vortex tube, the sampling amount of gas per unit time is increased, thereby improving the detection quality and reducing the detection error; at the same time, under the action of "rotating stirring" of the gas by the vortex tube, methane and large molecular tetrahydrothiophene are fully mixed, thereby improving the detection quality of natural gas by the gas detector and further reducing the detection error. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is a partial cross-sectional schematic diagram of the present invention;

[0026] Figure 3 It is an enlarged schematic diagram of the structure at the support plate;

[0027] Figure 4 A schematic diagram of the structure of the support frame.

[0028] Among them: 1. inner tube; 2. air collecting chamber; 3. outer tube; 4. support frame; 5. support plate; 6. three-way pipe; 7. vortex tube; 8. damping release port; 9. air inlet; 10. baffle; 11. notch; 12. fixed cylinder; 13. rotating plate; 14. notch; 15. adjusting cylinder; 16. block; 17. second support block; 18. support foot; 19. driving rod; 20. screw; 21. first support block; 22. elbow; 23. internal threaded sleeve; 24. vacuum pump; 25. exhaust pipe; 26. fixed plate. DETAILED DESCRIPTION

[0029] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0030] Example: Please refer to Figure 1-4A natural gas detection device comprises a vortex tube 7 connected to a natural gas discharge port through an inner tube 1, a gas collecting chamber 2 connected to the cold end of the vortex tube 7, and an outer tube 3 connected to the inside of the gas collecting chamber 2, wherein the end of the outer tube 3 away from the gas collecting chamber 2 is connected to a gas detector, and the hot end of the vortex tube 7 is connected to the atmosphere; wherein the gas detector adopts a Dräger X-am500 electronic semiconductor instrument, and when natural gas needs to be detected, the natural gas in the discharge port will flow through the inner tube 1, the vortex tube 7, the gas collecting chamber 2 and the outer tube 3 in sequence, and finally enter the gas detector for detection; in this process, the vortex tube 7 The characteristics of gas flow can be improved, thereby eliminating the influence of the "Knudsen flow state" (narrow tube and low speed); that is, through the characteristics of gas flow amplification of the vortex tube 7, the gas sampling volume per unit time is increased. Through experiments, it can be concluded that by replacing the conventional pump with the vortex tube 7, the original 0.4 liters / min is increased to 40 liters / min, thereby increasing the gas volume per unit time, and under the action of the vortex tube 7 "rotating stirring" of the gas, methane and large molecular tetrahydrothiophene are fully mixed, thereby improving the detection quality of natural gas by the gas detector and reducing the detection error.

[0031] In the present embodiment, a damping release port 8 is further provided on the gas collecting chamber 2. The damping release port 8 can be in the form of a pressure relief valve to prevent excessive pressure inside the gas collecting chamber 2, thereby improving the stability of gas flow, reducing noise generation, and improving the quality of gas detection; and the damping release port 8 is connected to an exhaust pipe 25 through a second hose, and the exhaust pipe 25 opens upward, wherein the exhaust pipe 25 is a steel pipe, and the gas inside the gas collecting chamber 2 is vertically discharged from the exhaust pipe 25 to the atmosphere, thereby preventing the gas with a lower temperature in the cold end of the vortex tube 7 from being sprayed out from the damping release port 8 to the detection personnel; the exhaust pipe 25 is installed in the middle of the vortex tube 7 through an elastic clamp, which is convenient for the installation and disassembly of the exhaust pipe 25; and the vortex tube The hot end of 7 is connected with a bend pipe 22, and the opening of the bend pipe 22 faces upward to prevent the gas at the hot end of the vortex tube 7 from spraying toward the inspector, thereby ensuring the safety of the inspector; an internally threaded sleeve 23 is provided at the end of the bend pipe 22, and the hot end of the vortex tube 7 is provided with an external thread threadedly connected to the internally threaded sleeve 23, and a sealing gasket is provided between the bottom of the internally threaded sleeve 23 and the end of the hot end of the vortex tube 7, so as to facilitate the disassembly and sealing of the bend pipe 22; in addition, the outer walls of the bend pipe 22, the vortex tube 7, the gas collecting chamber 2 and the related connecting pipes are provided with a thermal insulation layer, thereby ensuring the safety of the inspector; in addition, since the natural gas will be retained in the gas collecting chamber 2 and its related pipes after the detection, it will cause certain safety hazards to each other, and will also affect the next detection Quality, therefore, a fixing plate 26 is provided on the outer wall of the gas collecting chamber 2 in the present embodiment, and an air pump 24 is fixedly connected to the fixing plate 26, an air inlet pipe of the air pump 24 is connected to the interior of the gas collecting chamber 2, and an air outlet pipe of the air pump 24 is connected to the atmosphere, and a valve is provided on the air inlet pipe. When testing, the valve is closed, and when the testing is completed, the valve is opened, and the air pump 24 is started, so as to discharge the natural gas in the gas collecting chamber 2 and related pipelines; the inner tube 1 is located inside the outer tube 3, and the upper part of the inner tube 1 passes through the outer tube 3 and the top of the gas collecting chamber 2 at the same time, and one end of the inner tube 1 passing through the top of the gas collecting chamber 2 is connected to the vortex tube 7, and the bottom end of the inner tube 1 passes through the outer tube 3, and the bottom end of the inner tube 1 is connected to the natural gas discharge port, so that the structure of the device is more compact, It is convenient to transfer the device; wherein, the inner tube 1 and the outer tube 3 are both made of steel tubes, and the lower part of the outer tube 3 is connected with a three-way tube 6, and one of the gas outlet ends of the three-way tube 6 is connected with a gas pressure gauge, so that the gas pressure during detection can be observed in real time to prevent the quality of detection from being affected by excessive pressure or too low pressure, and the other gas outlet of the three-way tube 6 is connected with a filter, a gas flow meter and a gas detector in sequence through a first hose, wherein the filter can be a magnetic bead filter, thereby improving the gas detection quality and facilitating the collection of gas flow data; in addition, when the detection pipe section is the end or the infrequent gas flow pipe section, tetrahydrothiophene is adsorbed by the inert pipe wall and attenuated, and the gas sample obtained by the conventional suction pump is 0.4L / min, the detection capacity is not enough to detect the real data in this state; in addition, in the prior art, affected by the structure of the rotor flowmeter, the rotor flowmeter with a shorter display scale is different from the rotor flowmeter with a longer display scale after field testing, and the main factor is the factor of excessive flow through the aperture under low pressure; some rotor flowmeters are one of the causes of the Knudsen number fluid factor error. After field testing, the content of tetrahydrothiophene will not change significantly when the flow rate is increased from 0.5L / min to 1.5L / min; therefore, the present invention uses The Maxwell vortex tube 7 is used as the front stage of sampling, in which the hot end is the release port (viscous force effect), and the cold end is the reading port (inertial force effect). The gas collecting cavity 2 is fixedly connected to the outer tube 3. By increasing the flow rate, the gas detection amount per unit time is increased, thereby eliminating the problem of tetrahydrothiophene being adsorbed by the inert tube wall and attenuated when the detection tube section is the end or infrequent gas flow tube section, thereby eliminating the influence of the "Knudsen flow state" (narrow tube low speed), which is conducive to improving the authenticity of natural gas detection; in addition, relevant valves are provided in the pipeline of this device to facilitate the opening and closing of the device. .

[0032] In this embodiment, an adjustable support frame 4 is installed at the bottom of the outer tube 3, and the support frame 4 includes a first support block 21 fixedly connected to the bottom of the outer tube 3, a screw 20 fixedly connected to the bottom of the first support block 21, an adjustment cylinder 15 threadedly connected to the screw 20, and a second support block 17 rotatably connected to the upper part of the adjustment cylinder 15, a support foot 18 is rotatably connected to the first support block 21, a driving rod 19 is rotatably connected to the middle of the support foot 18, and an end of the driving rod 19 away from the support foot 18 is rotatably connected to the second support block 17, the cross-section of the support foot 18 is a U-shaped groove, one end of the driving rod 19 is located inside the U-shaped groove, and a notch 14 is provided on the first support block 21 and the second support block 17, and one end of the driving rod 19 and the support foot 18 are both located in the notch 14; when the device needs to be adjusted When performing stable support, it is only necessary to rotate the adjusting cylinder 15 to adjust the opening angle of the supporting feet 18, thereby achieving stable placement of the device; a block 16 is provided on the top of the screw rod 20 to prevent the adjusting cylinder 15 from falling off the screw rod 20; and the middle part of the outer tube 3 is fixedly connected to the support plate 5 through the fixed cylinder 12, and a baffle 10 is fixedly connected to the edge of the support plate 5, which is convenient for the placement of gas detectors or related tools; a number of notches 11 are provided on the support plate 5 to prevent accumulation of rainwater; and a rotating plate 13 is rotatably connected to the fixed cylinder 12, and the edge of the rotating plate 13 is buckled on the outer wall of the baffle 10, and the operator can perform operations such as data recording on the rotating plate 13. In addition, by rotating the rotating plate 13, it is convenient for the operator to record at different positions, thereby improving the practicality of the device.

[0033] The working principle of this embodiment is as follows: when it is necessary to detect the gas, it is only necessary to move the device to the specified position, then rotate the adjustment cylinder 15, open the support legs 18 to a certain angle, then connect the natural gas discharge port to the inner tube 1 through the air pipe, then open the relevant valves, and the natural gas to be tested will flow into the inner tube 1, the vortex tube 7, the gas collecting cavity 2 and the outer tube 3 in sequence, and finally flow into the gas detector for detection; therefore, the present invention improves the gas flow rate by adopting the vortex tube 7, thereby eliminating the influence of the "Knudsen flow state" (narrow tube and low speed); that is, through the gas flow amplification characteristic of the vortex tube 7, the gas sampling amount per unit time is increased, thereby improving the detection quality and reducing the detection error; at the same time, under the action of the vortex tube 7 on the "rotating stirring" of the gas, the methane and the large molecular tetrahydrothiophene are fully mixed, thereby improving the detection quality of the gas detector for natural gas and further reducing the detection error.

[0034] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an element centered thereon. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an element centered thereon. The terms "upper", "lower", "left", "right", "front", "rear" and similar expressions used herein are for illustrative purposes only.

[0035] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A natural gas detection device, characterized in that: It comprises a vortex tube (7) connected to a natural gas discharge port via an inner tube (1), a gas collecting chamber (2) connected to the cold end of the vortex tube (7), and an outer tube (3) connected to the interior of the gas collecting chamber (2), wherein one end of the outer tube (3) away from the gas collecting chamber (2) is connected to a gas detector, and the hot end of the vortex tube (7) is connected to the atmosphere.

2. The natural gas detection device according to claim 1, characterized in that: The gas collecting chamber (2) is fixedly connected to the outer tube (3), one end of the outer tube (3) is located inside the gas collecting chamber (2), and an air inlet (9) is provided on the outer tube (3) located inside the gas collecting chamber (2).

3. The natural gas detection device according to claim 2, characterized in that: The inner tube (1) is located inside the outer tube (3); the upper portion of the inner tube (1) simultaneously penetrates the outer tube (3) and the top of the gas collecting chamber (2); one end of the inner tube (1) that penetrates the top of the gas collecting chamber (2) is connected to the vortex tube (7); the bottom end of the inner tube (1) penetrates the outer tube (3), and the bottom end of the inner tube (1) is connected to the natural gas release port.

4. The natural gas detection device according to claim 1, characterized in that: The gas collecting chamber (2) is also provided with a damping release port (8).

5. The natural gas detection device according to claim 1, characterized in that: The lower part of the outer tube (3) is connected to a three-way tube (6), one gas outlet end of the three-way tube (6) is connected to a gas pressure gauge, and the other gas outlet of the three-way tube (6) is connected to a filter, a gas flow meter and the gas detector in sequence through a first hose.

6. The natural gas detection device according to claim 1, characterized in that: The hot end of the vortex tube (7) is connected to a curved tube (22), and the opening of the curved tube (22) faces upward.

7. The natural gas detection device according to claim 1, characterized in that: An adjustable support frame (4) is installed at the bottom of the outer tube (3), and the support frame (4) comprises a first support block (21) fixedly connected to the bottom of the outer tube (3), a screw rod (20) fixedly connected to the bottom of the first support block (21), an adjustment cylinder (15) threadedly connected to the screw rod (20), and a second support block (17) rotatably connected to the upper part of the adjustment cylinder (15), the first support block (21) is rotatably connected to a support foot (18), the middle part of the support foot (18) is rotatably connected to a driving rod (19), and the end of the driving rod (19) away from the support foot (18) is rotatably connected to the second support block (17).

8. The natural gas detection device according to claim 7, characterized in that: The cross section of the supporting foot (18) is a U-shaped groove, one end of the driving rod (19) is located inside the U-shaped groove, and both the first supporting block (21) and the second supporting block (17) are provided with a notch (14), and one end of the driving rod (19) and the supporting foot (18) are both located in the notch (14).

9. The natural gas detection device according to claim 1, characterized in that: The middle part of the outer tube (3) is fixedly connected to a support plate (5) via a fixed tube (12); a baffle (10) is fixedly connected to the edge of the support plate (5); a rotating plate (13) is rotatably connected to the fixed tube (12); and the edge of the rotating plate (13) is buckled onto the outer wall of the baffle (10).

10. The natural gas detection device according to claim 1, characterized in that: A fixing plate (26) is provided on the outer wall of the gas collecting chamber (2), and an air pump (24) is fixedly connected to the fixing plate (26). An air inlet pipe of the air pump (24) is connected to the interior of the gas collecting chamber (2), and an air outlet pipe of the air pump (24) is connected to the atmosphere. A valve is provided on the air inlet pipe.

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