Air-blast source reflection device and exploration process

Abstract

The application discloses a gas explosion source reflection device and an exploration process, which comprises a cavity, a top cover and an igniter, inner and outer limiting tubes are arranged on the cavity and the top cover respectively, the igniter is installed on the inner and outer limiting tubes, an ignition wire at the head of the igniter extends into the cavity, a one-way valve is arranged on the part of the inner limiting tube in the cavity, the top head of the igniter abuts against the one-way valve, a locking assembly is arranged on the top cover, a hook and loop assembly is arranged on the top cover, an unlocking rope is connected to the top end of the igniter, and the other end of the unlocking rope passes through the hook and loop assembly with a horizontal height lower than the top end of the igniter. The igniter and the cavity are arranged in a detachable mode, the igniter is fixed in the cavity through the locking assembly, when needed, the locking assembly is opened by pulling the unlocking rope, so that the igniter is ejected from the cavity, the igniter is separated from the cavity, and the situation that gas burns when exhaust is caused by high-voltage pack, capacitor discharge and the like of the igniter during gas replacement of the cavity is avoided, thereby reducing the safety hidden danger.

Description

Technical Field

[0001] This invention relates to the field of geological exploration, specifically to a gas explosion source reflection device and exploration process. Background Technology

[0002] Shallow seismic exploration typically uses explosive sources. Explosives, as a type of gas explosion source reflector and energetic material in exploration processes, were once widely used in artificial sources. However, during the feasibility study and exploration phase, they encountered problems such as complicated approval processes and long cycles, which once caused delays in project milestones.

[0003] When oxygen mixes with combustible gases, a chemical reaction (combustion, detonation) can occur under certain energy ignition conditions, releasing a large amount of chemical energy. For example, the chemical energy released by the explosion of 1 kg of TNT is approximately 4.2 MJ. The equivalent energy can be achieved by reacting 4.5 moles of methane with a stoichiometric ratio of oxygen. This energy density is far higher than that of artificial seismic sources currently powered by physical potential energy, and the products are environmentally friendly water and a small amount of carbon dioxide. Therefore, current seismic exploration work mostly uses gas explosion seismic sources.

[0004] When using a gas explosion source, there is a possibility of misfires. The reasons include igniter malfunction, cavity leakage, and previously low gas pressure. Since the source is buried underground, the only way to deal with misfires is to cut off the power and vent the gas. At this time, the igniter is still installed on the source. Since the cause of the igniter malfunction is unknown, among the foreseeable risk factors, there is a possibility that the gas may burn during venting due to discharge of the igniter's high-voltage coil, capacitor, etc., which could cause injury to the operator and pose a significant safety hazard. Summary of the Invention

[0005] The purpose of this invention is to provide a gas explosion source reflection device and exploration process to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a gas explosion source reflection device, comprising a cavity, a top cover, and an igniter. The top cover is detachably installed on the top of the cavity. The top cover is provided with a gas interface that is connected to the cavity. The gas interface is connected to a gas pipe. An injection valve is provided at the outer end of the gas pipe. An inner limiting tube and an outer limiting tube are respectively provided on the cavity and the top cover. The igniter passes through and is installed on the inner limiting tube and the outer limiting tube in sequence. The part of the igniter near the head is sealed to the inner limiting tube. The ignition wire of the igniter head extends into the cavity. The part of the inner limiting tube inside the cavity has a one-way valve. The ignition wire of the igniter has a top that abuts against the one-way valve. A locking component is provided on the top cover.

[0007] The locking assembly includes a pull ring and a support spring. The pull ring is hinged to the top cover, and the top of the pull ring abuts against a hook on the igniter. The igniter has a support spring nested between the hook and the top cover. The locking assembly also includes a tensioning member, with its two ends connected to the pull ring and the top cover respectively. The tensioning member provides a pulling force to the pull ring away from the igniter. The top cover has a hook and loop assembly, and the top of the igniter is connected to an unlocking rope. The other end of the unlocking rope passes through the hook and loop assembly at a horizontal height lower than the top of the igniter.

[0008] Meanwhile, the one-way valve includes a plug, a blocking spring, and a locking cover. The locking cover is threaded onto the inner limiting tube. The plug is located inside the locking cover. The blocking spring is located between the locking cover and the plug. The blocking spring provides elastic force to the plug to press against the inner limiting tube. The plug abuts against the plug.

[0009] Furthermore, the portion of the igniter near the head is provided with a sealing ring, which is nested in a sealed manner with the inner wall of the inner limiting tube.

[0010] Furthermore, the side of the top that abuts against the plug is a slope, and the horizontal height of the end of the slope near the ignition wire is lower than that of the end away from the ignition wire. The locking cover is provided with through grooves around its perimeter to expand the gas contact space.

[0011] Furthermore, the main body of the hook and ring assembly is in the shape of a hanging ring, and a rolling sleeve for rolling is nested in the middle of the hook and ring assembly.

[0012] Furthermore, the hook and ring assembly includes a movable ring, a base, and a limiting slide plate. The base is fixed to the top cover, one end of the movable ring is connected to the top cover via a hinge, and the other end of the movable ring is located inside the base. The limiting slide plate is slidably engaged on the base to limit the swing of the movable ring. The limiting slide plate is provided with a follower ring, and an outwardly extending pull rod is fixed on the pull ring, the pull rod passing through the follower ring.

[0013] A gas explosion source exploration technique includes the following steps:

[0014] S1: Lower the well, connect the gas inlet of the gas explosion source cavity to the gas pipe, connect the igniter to the detonation wire and the unlocking rope, wrap the gas pipe, detonation wire and unlocking rope with the casing, and mark the position of the unlocking rope at the top of the casing. Then, thread the traction rope through the iron ring of the gas explosion source. Both the traction rope and the casing pass through a diaphragm. The diaphragm covers the top of the gas explosion source cavity. Then, connect the traction rope to the winch and use the winch to lower the gas explosion source to the bottom of the well.

[0015] S2: Seal the well. Fill the well with fine soil to ensure that the well is completely filled. Cover the well opening with a buffer plate wider than the well opening and cover the buffer plate with two sandbags or soil.

[0016] S3: Instrument installation: Install the vibration velocity measuring device on the ground surface with a horizontal aid and point the X direction toward the explosion center;

[0017] S4: Gas injection. Connect the methane cylinder and oxygen cylinder to the gas injection line respectively. Connect the gas injection line to the gas injection valve of the gas pipe. Then, inject methane into the gas explosion source cavity through the gas injection line in sequence, close the methane cylinder and remove the cylinder, inject oxygen, close the oxygen cylinder and remove the cylinder.

[0018] S5: Activate, turn on the vibration velocity measuring device, connect the detonator and the data cable, start charging the detonator to above 280 volts, and then ignite according to the instructions of the on-site commander. The vibration velocity measuring device obtains the corresponding data. After activation is completed, retract the detonator.

[0019] When detonation fails, the dud needs to be handled, including the following steps:

[0020] S5-1: Disconnect the detonator and data cable, pull the unlocking rope to release the igniter from the pull ring, and then the support spring provides elasticity to push the igniter out.

[0021] S5-2: Connect the exhaust pipe to the air pipe with an air injection valve. Place the exhaust pipe outlet into an iron bucket filled with water. Open the valve to keep the air bubbles in the iron bucket from being released continuously until no more air bubbles are generated.

[0022] S5-3: Connect the nitrogen cylinder to the injection line, then connect the injection line to the injection valve of the gas pipe, and inject nitrogen to 2MPa at a pressure increase rate of no more than 0.5MPa per minute. Then close the nitrogen cylinder and disconnect the injection line. Use the injection valve to purge the gas inside the wall. Then perform the nitrogen injection and venting operation again.

[0023] S5-4: Then cut the traction rope, data cable, and air hose to restore the ground surface;

[0024] S6: Cleaning up involves restoring the surface of the well site after activation and recovering and centrally processing the abandoned traction ropes, data cables, gas pipes, unlocking ropes, and casings at the wellhead.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. This invention features a detachable design between the igniter and the cavity, with a locking component securing the igniter within the cavity. When needed, the locking component is released by pulling the unlocking rope, allowing the igniter to pop out of the cavity. This prevents the igniter from discharging during gas replacement of the cavity, thus avoiding the risk of combustion of exhaust gas due to discharge from the igniter's high-voltage coil or capacitor, thereby reducing safety hazards. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0028] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0029] Figure 2 This is a schematic diagram of the arrangement of the present invention at the bottom of a well;

[0030] Figure 3 It is a 3D schematic diagram of the igniter, locking assembly, and hook and loop assembly;

[0031] Figure 4 This is a front view of the igniter, hook and ring assembly, and one-way valve.

[0032] Figure 5 This is a front view of the igniter and the one-way valve working together;

[0033] Figure 6 yes Figure 5 Another implementation diagram;

[0034] Figure 7 This is a three-dimensional structural diagram of the hook and loop assembly.

[0035] Figure 8 This is a front view of the hook and loop assembly.

[0036] Figure 9 This is a graph of raw earthquake data obtained by a seismic wave velocity measuring instrument.

[0037] Figure 10 This is an amplitude-frequency analysis diagram of seismic exploration data.

[0038] In the picture:

[0039] A. Traction rope; B. Data cable; C. Air tube; D. Unlocking rope; E. Sleeve; F. Diaphragm;

[0040] 1. Cavity; 1a. Inner limiting tube;

[0041] 2. Top cover; 2a. Outer limiting tube; 21. Traction ring; 22. Hook and ring assembly; 23. Roller sleeve;

[0042] 221. Movable ring; 222. Base; 223. Limiting slide; 224. Follower ring;

[0043] 3. Gas inlet; 4. Ignition device; 41. Hook; 42. Sealing ring; 43. Top end;

[0044] 5. Locking assembly; 51. Pull ring; 52. Support spring; 53. Tensioning component; 54. Pull rod;

[0045] 6. One-way valve; 61. Plug; 62. Blocking spring; 63. Locking cover. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] This invention provides a gas explosion source reflection device and exploration process technology solution: such as Figure 1-8 As shown, a gas explosion source reflection device includes a cavity 1, a top cover 2, and an igniter 4. The top cover 2 is detachably installed on the top of the cavity 1. The top cover 2 is provided with a gas interface 3, which is connected to the cavity 1. The gas interface 3 is connected to a gas pipe C. An air injection valve is provided at the outer end of the gas pipe C. The cavity 1 and the top cover 2 are respectively provided with an inner limiting tube 1a and an outer limiting tube 2a. The igniter 4 passes through and is installed on the inner limiting tube 1a and the outer limiting tube 2a in sequence. The part of the igniter 4 near the head is sealed to the inner limiting tube 1a. The ignition wire of the igniter 4 extends into the cavity 1. The part of the inner limiting tube 1a inside the cavity 1 has a one-way valve 6. The ignition wire of the igniter 4 is provided with a top head 43 that abuts against the one-way valve 6. The top cover 2 is provided with a locking component 5. The part of the igniter 4 near the head is provided with a sealing ring 42. The sealing ring 42 is sealed and nested with the inner wall of the inner limiting tube 1a.

[0048] The locking assembly 5 includes a pull ring 51 and a support spring 52. The pull ring 51 is connected to the top cover 2 by a hinge. The top of the pull ring 51 abuts against the hook 41 provided on the igniter 4. The support spring 52 is nested between the hook 41 and the top cover 2 in the igniter 4. The locking assembly 5 also includes a tensioning member 53. Optionally, the tensioning member 53 is a tension spring or an elastic pull rope. The two ends of the tensioning member 53 are connected to the pull ring 51 and the top cover 2 respectively. The tensioning member 53 provides a pulling force to the pull ring 51 away from the igniter 4. The top cover 2 is provided with a hook and loop assembly 22. The top of the igniter 4 is connected to an unlocking rope D. The other end of the unlocking rope D passes through the hook and loop assembly 22, which is at a horizontal height lower than the top of the igniter 4.

[0049] Meanwhile, the one-way valve 6 used is designed to cooperate with the locking assembly 5. It includes a plug 61, a blocking spring 62, and a locking cover 63. The locking cover 63 is threaded onto the inner limiting tube 1a. The plug 61 is located inside the locking cover 63. The blocking spring 62 is located between the locking cover 63 and the plug 61. The blocking spring 62 is used to provide the plug 61 with a spring force to press against the inner limiting tube 1a. The top head 43 abuts against the plug 61.

[0050] In order to cooperate with the locking component 5, the main body of the hook and loop assembly 22 is in the shape of a ring. Optionally, the hook and loop assembly 22 has a rolling sleeve 23 nested in the middle for rolling, thereby reducing friction between the unlocking rope D and the locking component 5.

[0051] In a preferred embodiment, the side of the top head 43 that abuts against the plug 61 is an inclined surface, and the horizontal height of the end of the inclined surface near the ignition wire is lower than that of the end away from the ignition wire. The locking cover 63 is provided with through grooves around its perimeter to expand the gas contact space, thereby increasing the contact space between the ignition wire and the gas in the cavity 1.

[0052] It should be noted that, as those skilled in the art know, functional coatings such as anti-impact and anti-static coatings can be applied to the inner limit tube 1a, outer limit tube 2a, one-way valve 6, igniter 4, top cover 2, and other parts with linkage contact.

[0053] After the air explosion source is set up, such as Figure 2 As shown, the gas explosion source exploration process, which utilizes a gas explosion source in conjunction with other methods, includes the following steps:

[0054] S1: Lower the well, connect the gas inlet 3 of the gas explosion source cavity 1 to the gas pipe C, connect the igniter 4 to the detonation wire and the unlocking rope D, wrap the gas pipe C, the detonation wire and the unlocking rope D with the casing E, and mark the position of the unlocking rope D at the top of the casing E. Then, thread the traction rope A through the iron ring of the gas explosion source, and both the traction rope A and the casing E pass through a cover F. The cover F covers the top of the gas explosion source cavity 1. Then, connect the traction rope A to the winch and use the winch to lower the gas explosion source cavity 1 to the bottom of the well. At this time, the gas explosion source cavity 1 is at the bottom of the well, and the cover F still covers the top of the cavity 1.

[0055] S2: Seal the well. Fill the well with fine soil to ensure that the well is completely filled. Cover the well with a buffer plate wider than the well opening and cover the buffer plate with two sandbags or soil. At this time, the soil filled into the hole will be stacked on the cover F. There is little or no soil accumulation in the space between the cover F and the top cover 2, so that the unlocking rope D, the igniter 4 and the locking component 5 have room to move.

[0056] S3: Instrument installation. Install the vibration velocity measuring device on the ground with a horizontal aid and point the X direction towards the center of the explosion. As is known, the vibration velocity measuring device can be fixed by ground plugs, plaster, M5 coarse screws at the bottom of the device, built-in magnetic rings, etc., which will not be elaborated here.

[0057] S4: Inject gas. Connect the methane cylinder and oxygen cylinder to the gas injection line C respectively. Connect the gas injection line C to the gas injection valve of the gas pipe C. Then, inject methane into the gas explosion source cavity 1 through the gas injection line C in sequence, close the methane cylinder and remove the cylinder, inject oxygen, close the oxygen cylinder and remove the cylinder.

[0058] S5: Activate, turn on the vibration velocity measuring device, connect the detonator and data line B, begin charging the detonator to above 280 volts, then ignite according to the on-site commander's instructions. The vibration velocity measuring device will obtain the corresponding readings, such as... Figure 9 , Figure 10 The data shown indicates that the detonator was withdrawn after activation.

[0059] When detonation fails, the dud needs to be handled, including the following steps:

[0060] S5-1: Disconnect the detonator and data line B, pull the unlocking rope D to disengage the igniter 4 from the pull ring 51, and then the support spring 52 provides elasticity to push the igniter 4 out.

[0061] Specifically, since the unlocking rope D is wrapped by the casing E, the soil filling the well will not compress the unlocking rope D, allowing the unlocking rope D to move freely. Before pulling up the unlocking rope D, the pull ring 51 hooks the igniter 4 through the hook 41. After pulling the unlocking rope D, the unlocking rope D passes around the hook ring assembly 22, converting the upward pull of the unlocking rope D into the downward movement of the igniter 4. After the igniter 4 moves down, the pull ring 51 is pulled open by the tensioning member 53, and the igniter 4 is lifted up by the support spring 52 and separated from the cavity 1. At the same time, the blocking spring 62 drives the plug 61 to rise and press against the inner limit tube 1a, thereby making the cavity 1 closed.

[0062] S5-2: Connect the air inlet valve from exhaust pipe C to air pipe C. Place the outlet of exhaust pipe C into an iron bucket filled with water. Open the valve to keep the bubbles in the iron bucket from being released continuously until no more bubbles are generated.

[0063] S5-3: Connect the nitrogen cylinder to the injection line C, then connect the injection line C to the injection valve of the gas pipe C, and inject nitrogen to 2MPa at a pressure increase rate of no more than 0.5MPa per minute. Then close the nitrogen cylinder and disconnect the injection line C. Use the injection valve to purge the gas inside the wall, and then perform the nitrogen injection and venting operation again.

[0064] S5-4: Then cut the traction rope A, data cable B and air pipe C, leaving the equipment at the bottom of the well, such as the gas explosion source cavity 1, at the bottom of the well. Alternatively, the well can be dug out. Skilled personnel can handle the situation according to actual needs, but the surface must be restored.

[0065] S6: Cleaning up involves restoring the surface of the well site after activation and recovering and centrally processing the abandoned traction rope A, data cable B, gas pipe C, unlocking rope D, and casing E from the wellhead.

[0066] In a preferred embodiment, to pull the igniter 4 more fully out of the cavity 1, such as... Figure 7-8 As shown, optionally, the hook and loop assembly 22 includes a movable ring 221, a base 222, and a limiting slide plate 223. The base 222 is fixed to the top cover 2. One end of the movable ring 221 is connected to the top cover 2 via a hinge, and the other end of the movable ring 221 is located inside the base 222. The limiting slide plate 223 is slidably engaged on the base 222. The limiting slide plate 223 is used to limit the swing of the movable ring 221. The limiting slide plate 223 is provided with a follower ring 224, and an outwardly extending pull rod 5 is fixed on the pull ring 51. 4. The pull rod 54 passes through the follower ring 224. Specifically, after the igniter 4 moves down and the pull ring 51 is pulled open by the tensioner 53, the pull ring 51 drives the follower ring 224 to move outward through the pull rod 54. The follower ring 224 drives the limiting slide plate 223 to move outward, so that it is no longer in contact with the movable ring 221, allowing one part of the movable ring 221 to be released. This allows the movable ring 221 to swing through the hinge, and at the same time, the unlocking rope D can be wound out of the movable ring 221, which can further pull the igniter 4 up and completely separate it from the cavity 1.

Claims

1. A gas detonation source reflection device, comprising a cavity, a top cover and an igniter, the top cover is detachably mounted on the top end of the cavity, the top cover is provided with a gas interface and the gas interface is connected with the cavity, the gas interface is connected with a gas pipe, the outer end of the gas pipe is provided with an air injection valve, characterized in that: the cavity and the top cover are respectively provided with an inner limiting tube and an outer limiting tube, the igniter passes through and is mounted on the inner limiting tube and the outer limiting tube in sequence, the part of the igniter close to the head is sealingly connected with the inner limiting tube, and the ignition wire of the head of the igniter extends into the cavity; the part of the inner limiting tube in the cavity is provided with a one-way valve, the ignition wire of the igniter is provided with a head and abuts against the one-way valve; the top cover is provided with a locking assembly, the locking assembly comprises a pull ring and a bracket spring, the pull ring is connected with the top cover through a hinge, the top end of the pull ring abuts against a hook provided on the igniter, the bracket spring is nested between the hook and the top cover, the locking assembly further comprises a tensioning piece, the two ends of the tensioning piece are respectively connected with the pull ring and the top cover, and the tensioning piece provides a pulling force for the pull ring in a direction away from the igniter; the top cover is provided with a shackle assembly, the top end of the igniter is connected with an unlocking rope, and the other end of the unlocking rope passes through the shackle assembly which is lower than the top end of the igniter in horizontal height. The one-way valve comprises a plug, a blocking spring and a locking cover, the locking cover is engaged with the inner limiting tube through threads, the plug is arranged in the locking cover, and the blocking spring is arranged between the locking cover and the plug, the blocking spring is used to provide the plug with a spring force to abut against the inner limiting tube, and the head abuts against the plug. The side of the head used to abut against the plug is a bevel, and the horizontal height of the end of the bevel close to the ignition wire is lower than that of the end away from the ignition wire. The locking cover is provided with a through groove around the locking cover for expanding the gas contact space. The part of the igniter close to the head is provided with a sealing ring, and the sealing ring is sealingly nested with the inner wall of the inner limiting tube.

2. A gas-blast source reflector according to claim 1, wherein: The main body of the shackle assembly is a hanging ring, and the shackle assembly is nested with a rolling sleeve for rolling in the middle part.

3. A gas-blast source reflector according to claim 2, wherein: The shackle assembly comprises a movable ring, a base and a limiting slide plate, the base is fixed on the top cover, one end of the movable ring is connected with the top cover through a hinge, the other end of the movable ring is located in the base, the limiting slide plate is slidingly clamped on the base, and the limiting slide plate is used to limit the swing of the movable ring. The limiting slide plate is provided with a follower ring, the pull ring is fixed with an outwardly extending pulling rod, and the pulling rod passes through the follower ring.

4. A gas-blast source reflector according to claim 2, wherein: The method comprises the following steps:

5. A gas-blast source reflector according to claim 1, wherein: S1: downhole, connect the gas pipe with the gas interface of the gas detonation source cavity, connect the igniter with the detonation wire and the unlocking rope, cover the gas pipe, the detonation wire and the unlocking rope with a sleeve, mark the position of the unlocking rope at the top end of the sleeve, then put the traction rope on the iron ring of the gas detonation source, the traction rope and the sleeve pass through a partition cover, the partition cover covers the top end of the gas detonation source cavity, then connect the traction rope with the winch, and put the gas detonation source into the bottom of the well by using the winch; 6. A gas-blast source reflector according to claim 1, wherein: S2: well sealing, fill fine soil into the detection well to ensure that the well is completely filled, and cover the well mouth with a buffer plate which is wider than the well mouth, and cover the buffer plate with two sandbags or soil covers.

7. A gas-blast source reflector according to claim 6, wherein: ​ 8. An air-blast seismic source exploration process using the air-blast seismic source reflection device of any one of claims 1-7, characterized in that: ​ ​ ​ S3: Instrument installation, install the shock wave velocity measurer on the ground by horizontal auxiliary installation, and point the X direction to the explosion center; S4: Gas injection, connect the gas injection pipeline to the methane gas cylinder and the oxygen gas cylinder respectively, connect the gas injection pipeline to the gas injection valve of the gas pipe, then inject methane, oxygen into the gas explosion source cavity in turn through the gas injection pipeline, close the methane gas cylinder and remove the gas cylinder, inject oxygen, close the oxygen gas cylinder and remove the gas cylinder; S5: Excitation, open the shock wave velocity measurer, connect the detonator and the data line, start charging the detonator to above 280 volts, then ignite according to the instruction of the site commander, the shock wave velocity measurer obtains the corresponding data, and the detonator is withdrawn after excitation is completed; S6: Cleaning, the well site after excitation is completed is restored to the ground, and the abandoned traction rope, data line, gas pipe, unlocking rope and casing at the well mouth are recovered and treated.

9. A gas-blast source exploration process according to claim 8, characterised in that: In step S5, when the detonation fails, the dummy bomb needs to be processed, including the following steps: S5-1: disconnect the detonator and the data line, pull the unlocking rope to make the igniter separate from the pull ring, then the spring of the support provides elastic force to fix the igniter; S5-2: connect the exhaust pipe to the gas injection valve of the gas pipe, put the exhaust pipe outlet into the iron bucket filled with water, open the valve to keep the bubbles in the iron bucket discontinuous, until no bubbles are generated; S5-3: connect the nitrogen gas cylinder to the gas injection pipeline, then connect the gas injection pipeline to the gas injection valve of the gas pipe, add nitrogen gas at a pressure increasing rate of not more than 0.5 MPa per minute to 2 MPa, then close the nitrogen gas cylinder and disconnect the gas injection pipeline, use the gas injection valve to empty the gas in the wall, and then perform nitrogen gas injection and exhaust operation again; S5-4: then cut the traction rope, data line and gas pipe, and restore the ground.

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