SF6 gas micro-water density monitoring device

Abstract

The utility model discloses a SF6 gas micro -water density monitoring devices contains micro -water detection module, inlet pipe, exhaust pipe, pump body, L type telescopic pipe and butt joint, drying cylinder, place cavity, step support surface, filter cartridge (infill drying agent), sliding sleeve, upper / lower limit convex ring, sliding groove and convex strip, boss, extruding block, fixed peg, spring, connecting rod, pressure gauge, wireless transmitting module, when working, the pump body draws gas and enters drying cylinder after micro -water detection, conical hole and extruding block - step support - sliding sleeve constitute forced flow structure, and make sample gas to pass through filter cartridge reflux equipment, and pressure gauge and wireless transmission realize pressure monitoring and data report, and the structure is convenient for installation maintenance, and inhibits bypass, and stable reflux moisture content, and improves detection result consistency.

Description

Technical Field

[0001] This utility model belongs to the field of SF6 micro-moisture detection technology, specifically relating to an SF6 gas micro-moisture density monitoring device. Background Technology

[0002] During the operation and maintenance of gas-insulated switchgear (GIS), circuit breakers, and instrument transformers containing SF6 gas chambers, it is often necessary to sample and perform online or near-online testing of the SF6 gas inside the chambers to assess the moisture content and density level of the insulating medium. The existing testing process typically involves: connecting an external monitoring device to the equipment's pre-reserved sampling port via a connector; drawing the sample gas with a micro-pump and sending it to a micro-moisture detection module; using a capacitive or other type of micro-moisture sensor to obtain the moisture content signal; and then, depending on operational needs, either releasing or returning the sample gas to the equipment. To reduce emissions and avoid introducing external moisture, a drying unit is often installed along the return path to re-dry the tested sample gas before returning it. Regarding field access, the relative position, height, and distance of the equipment sampling ports vary, and connections are often made using flexible hoses, rigid pipes, and adapters. For signal output, some devices use wired or wireless methods to transmit the test results to a terminal for maintenance recording and trend analysis.

[0003] In the above-mentioned detection-reflux process, the maintainability and flow path constraint of the reflux drying link are insufficient, which can easily lead to the sample gas not being forced to fully penetrate the drying medium and thus producing "bypass / circuiting". This makes the moisture content control of the reflux gas unstable, thereby affecting the reflection of the true moisture content of the equipment by the micro-moisture detection results.

[0004] Specifically, the following issues arise: Existing drying units often employ end-cap or filler structures, requiring the chamber to be opened and the absorbent material removed or refilled when replacing the desiccant. After disassembly, handling, or prolonged vibration, the position and orientation of the internal absorbent elements lack reliable limiting and support, and the sealing surface may shift, leading to localized low-resistance leakage channels. Furthermore, inadequate sealing and repositioning of the inlet and outlet during replacement can create short-circuit gas paths that do not penetrate the absorbent material. These factors significantly affect the dehumidification effect of the sample gas before recirculation, influenced by manual operation and assembly conditions. The moisture content of the recirculated gas fluctuates accordingly, potentially causing deviations in micro-moisture readings and carrying insufficiently dried sample gas back into the chamber during recirculation, adversely impacting the equipment's insulation operation. Utility Model Content

[0005] To address the problems existing in the prior art, the purpose of this utility model is to provide an SF6 gas micro-moisture density monitoring device. It can achieve convenient replacement and reliable positioning in the reflux drying unit, and force flow constraint on the gas path to stably control the moisture content of the reflux sample gas and improve the reliability of the detection results.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] An SF6 gas moisture density monitoring device includes a moisture detection module. The moisture detection module has an exhaust pipe at the top and an intake pipe at the bottom. Both the intake pipe and the exhaust pipe are equipped with L-shaped telescopic pipes. The ends of the L-shaped telescopic pipes are equipped with connectors, which are connected to the device to be monitored.

[0008] A drying cylinder is provided on the surface of the exhaust pipe. The detected gas flows back into the equipment through the drying cylinder. A placement cavity is provided above the surface of the drying cylinder. One side of the placement cavity is open. A stepped support surface is provided at the bottom of the placement cavity.

[0009] A filter cartridge is placed inside the placement cavity. The filter cartridge is positioned in the flow channel inside the drying cylinder and is filled with a high-efficiency desiccant.

[0010] Furthermore, a pump body is provided on the surface of the air intake pipe for transporting gas, and a wireless transmission module is provided on the outside of the micro-water detection module, with multiple wireless transmission modules transmitting detection signals to a computer terminal.

[0011] Furthermore, the placement cavity is provided with conical holes at both the top and bottom, and the end of the conical hole closer to the filter cartridge is larger than the other end;

[0012] An upper limit ring is provided above the surface of the drying cylinder, and a lower limit ring is provided below the surface of the drying cylinder.

[0013] Furthermore, a sliding sleeve is vertically slidably installed on the surface of the drying cylinder, and the sliding sleeve moves upward to seal the opening of the placement cavity.

[0014] Furthermore, a groove is provided along the axis on the back of the drying cylinder, and a convex strip is provided on the rear side of the inner wall of the sliding sleeve, the convex strip sliding inside the groove.

[0015] Furthermore, a boss is provided on the outer side of the sliding sleeve, and a pressing block is slidably installed on the inner side of the boss. The surface of the pressing block near the sliding sleeve is provided with an arc surface that is compatible with the filter cartridge.

[0016] The height of the extrusion block is the same as that of the placement cavity.

[0017] Furthermore, the extrusion block is symmetrically provided with fixing bolts on the side opposite to the center of the filter cylinder. Both fixing bolts pass through the boss, and the ends of the two fixing bolts are connected to connecting rods, which are placed outside the boss.

[0018] A spring is fitted on the surface of the fixing bolt, and the spring is placed inside the boss. The spring applies a thrust to the pressing block in the direction of the center of the sliding sleeve.

[0019] Furthermore, a pressure gauge is installed on the surface of the L-shaped telescopic tube connected to the bottom of the air inlet pipe, and the pressure gauge is used to detect the pressure of the gas inside the equipment.

[0020] Compared with the prior art, the beneficial effects of this utility model are:

[0021] Forced flow and gas path constraint are achieved; the tapered holes at the top and bottom of the placement chamber create a stable pressure difference at both ends of the filter cartridge; the filter cartridge and the placement chamber are tightly fitted and supported axially by the stepped support surface; the sliding sleeve moves upward to complete the circumferential sealing of the placement chamber opening and is limited in stroke by the upper and lower limit rings; the linear guide formed by the sliding groove and the convex strip limits the sliding sleeve to only axial movement to avoid rotation and gaps; the extrusion block in the boss, under the continuous pre-tension of the spring and the linear guidance of the fixing bolt, fits the outer circle of the filter cartridge with an arc surface and cooperates with the connecting rod to achieve loading and unloading control; the above structural combination constitutes a single gas path for forced flow through the desiccant layer inside the filter cartridge; bypass and around flow are suppressed; the sample gas before return is fully dehumidified to directly address the problem of insufficient airflow constraint in the reflux drying process in the background technology.

[0022] The consistency between the reflux moisture content and the detection is stabilized; the pump body establishes a continuous flow on the inlet side and forms a closed-loop sampling and reflux path with the inlet pipe—micro-moisture detection module—exhaust pipe—drying cylinder—equipment inner cavity; the L-shaped telescopic pipe and the butt joint achieve an adjustable sealing connection with the equipment sampling hole to reduce moisture disturbance caused by the entry of external air; the filter cartridge forms a forced penetration drying channel after being reliably positioned by the compression block and the stepped support surface; the moisture content of the sample gas detected by the micro-moisture detection module better reflects the true state of the equipment; the pressure gauge is used for self-testing of the seal after installation and pressure monitoring during operation to help judge leakage and flow fluctuations; the wireless transmission module realizes the synchronous reporting of detection data and operating status, which facilitates time series consistency verification at the terminal; the control of reflux gas moisture content tends to be stable; the reproducibility and reliability of the detection results are improved; the problem of "unstable control of reflux gas moisture content affecting detection reliability" in the background technology is specifically improved.

[0023] Convenience of maintenance and reliable positioning are guaranteed; the opening and closing of the sliding sleeve, with the upper and lower limit convex rings forming a clear assembly boundary; the connecting rod traction fixing bolt allows the extrusion block to quickly retract to expose the placement cavity opening; the filter cartridge can be picked up and put down as a whole, and the axial zero position is determined by the stepped support surface; after reset, the spring provides constant preload to maintain the contact between the extrusion block and the filter cartridge surface; the sliding groove and convex strip ensure repeated positioning of the sliding sleeve; under transportation and operating vibration conditions, the internal components of the drying unit are not easily misaligned; the replacement operation steps are simplified and the risk of air circuit short circuit caused by assembly differences is reduced; the problem of "unreliable positioning and sealing after changing the desiccant leading to bypass formation" in the background technology is resolved. Attached Figure Description

[0024] Figure 1This is a front view structural diagram of the present utility model;

[0025] Figure 2 This is a three-dimensional structural diagram of the present invention;

[0026] Figure 3 This is a three-dimensional structural diagram of the back of the drying cylinder of this utility model;

[0027] Figure 4 This is a frontal three-dimensional structural diagram of the drying cylinder of this utility model;

[0028] Figure 5 This is a schematic diagram of the exploded structure of the drying cylinder of this utility model;

[0029] Figure 6 This is a schematic diagram of the cross-sectional structure of the drying cylinder of this utility model;

[0030] Figure 7 This is a schematic diagram of the transverse top section structure of the sliding sleeve of this utility model.

[0031] The attached diagram lists the components represented by each number as follows:

[0032] 1. Micro-moisture detection module; 11. Air inlet pipe; 12. Exhaust pipe; 13. Wireless transmission module; 14. Pump body; 2. L-shaped telescopic pipe; 21. Connecting joint; 3. Drying cylinder; 31. Upper limit protrusion ring; 32. Lower limit protrusion ring; 33. Slide groove; 34. Placement cavity; 341. Stepped support surface; 35. Filter cartridge; 36. Sliding sleeve; 361. Protrusion strip; 362. Boss; 37. Extrusion block; 371. Fixing bolt; 38. Connecting rod; 39. Spring; 4. Pressure gauge. Detailed Implementation

[0033] To make the objectives and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of this utility model and does not strictly limit the scope of protection specifically claimed by this utility model.

[0034] Example 1:

[0035] like Figures 1-7As shown, an SF6 gas micro-moisture density monitoring device includes a micro-moisture detection module 1. The micro-moisture detection module 1 has an exhaust pipe 12 at the top and an intake pipe 11 at the bottom. Both the intake pipe 11 and the exhaust pipe 12 are equipped with L-shaped telescopic pipes 2, each with a connector 21 that connects to the device to be monitored. The micro-moisture detection module 1, as a detection unit, acquires micro-moisture parameters of the sample gas entering through the intake pipe 11 and exiting through the exhaust pipe 12 for condition assessment. The intake pipe 11 and the exhaust pipe 12 are arranged vertically to form an upward conveying path to cooperate with the pump body. 14. Establish a stable flow rate; L-shaped telescopic tube 2 is used to adjust the horizontal and vertical distance from the equipment sampling hole at the installation site and to achieve angle compensation to adapt to the reserved hole positions of different models of electrical equipment; connector 21 is used to form a detachable sealed connection with the sampling hole of the equipment to be monitored to reduce water disturbance caused by the entry of outside air; the cooperation between L-shaped telescopic tube 2 and connector 21 is used to maintain the continuity of the sampling channel during installation and disassembly to reduce the risk of leakage caused by frequent switching; micro-water detection module 1 detects the passing SF6 sample gas to output an electrical signal related to the micro-water content to provide input for subsequent wireless transmission.

[0036] A drying cylinder 3 is provided on the surface of the exhaust pipe 12. The gas after detection flows back into the equipment through the drying cylinder 3. A placement cavity 34 is provided above the surface of the drying cylinder 3. One side of the placement cavity 34 is open. A stepped support surface 341 is provided at the bottom of the placement cavity 34. The drying cylinder 3 is fixedly connected to the exhaust pipe 12 to establish a return drying channel on the exhaust side to reduce the water content of the returned sample gas. The placement cavity 34 is used to accommodate the filter cylinder 35 and corresponds to the position of the internal flow channel of the drying cylinder 3 to form a gas path that forces the filter cylinder 35 to penetrate. The stepped support surface 341 is used to support the filter cylinder 35 and limit the axial position of the filter cylinder 35 to reduce gas flow around caused by positional displacement. The drying cylinder 3 serves as a return unit to re-dry the sample gas after the detection process to meet the requirements of the relevant field technology for the stability of the returned water content.

[0037] A filter cartridge 35 is placed inside the placement cavity 34. The filter cartridge 35 is positioned in the flow channel inside the drying cylinder 3 and is filled with a high-efficiency desiccant. The external dimensions of the filter cartridge 35 match the dimensions of the placement cavity 34 to allow for surface contact sealing of the upper and lower inlets and outlets of the placement cavity 34 after placement, forcing the sample gas to pass through the high-efficiency desiccant layer inside the filter cartridge 35. The high-efficiency desiccant is used to adsorb moisture in the SF6 sample gas to reduce the water content before reflux. The tight fit between the filter cartridge 35 and the placement cavity 34 reduces the generation of bypass channels to meet the requirements of relevant technologies for avoiding flow around. During replacement operations, the filter cartridge 35 can be removed and replaced as a whole from the placement cavity 34 to meet the convenience requirements of on-site maintenance.

[0038] like Figure 1 and Figure 2As shown, a pump body 14 is provided on the surface of the air inlet pipe 11. The pump body 14 is used to transport gas. A wireless transmission module 13 is provided on the outside of the micro-moisture detection module 1. Multiple wireless transmission modules 13 transmit the detection signal to the computer terminal. The pump body 14 is used to establish a stable negative pressure on the air inlet side to continuously draw the SF6 sample gas inside the device to be monitored through the air inlet pipe 11 and send it into the micro-moisture detection module 1 for detection, and then enter the drying cylinder 3 through the exhaust pipe 12 for reflux drying. The working state of the pump body 14 and the flow resistance of the air inlet pipe 11 together determine the sample gas flow rate, which affects the response time and repeatability of the micro-moisture detection module 1. The wireless transmission module 13 is used to collect and encode the electrical signal output by the micro-moisture detection module 1 and send it to the computer terminal through the wireless link for recording and trend analysis. Multiple wireless transmission modules 13 are used to correspond to multiple detection tasks or different installation positions so as to realize channel monitoring and comparison on the same terminal.

[0039] like Figure 6 As shown, tapered holes are provided at both the top and bottom of the placement cavity 34, with the end of the tapered hole closer to the filter cartridge 35 being larger than the other end; an upper limit convex ring 31 is provided above the surface of the drying cartridge 3, and a lower limit convex ring 32 is provided below the surface of the drying cartridge 3; the tapered holes are used to form a convergence-diffusion transition structure at the top and bottom of the placement cavity 34 to establish a pressure difference at both ends of the filter cartridge 35 and guide the gas to enter the desiccant layer from the larger end face and then flow out from the smaller end face to enhance the forced penetration effect; the upper limit convex ring 31 and the lower limit convex ring 32 are used to limit the travel boundary of the sliding sleeve 36 and provide an axial positioning reference when the sliding sleeve 36 is in the upward blocking or downward opening state; the combination of the tapered holes and the limit convex rings is used to stabilize the airflow distribution in the return path to reduce local bypass caused by changes in installation posture.

[0040] like Figures 2-4 As shown, a sliding sleeve 36 is vertically slidably installed on the surface of the drying cylinder 3. The sliding sleeve 36 moves upward to seal the opening of the placement cavity 34. The sliding sleeve 36 is used to form an openable and closable shielding structure on the outer periphery of the drying cylinder 3 to close the opening of the placement cavity 34 in the working state and open the opening of the placement cavity 34 in the maintenance state. The sliding sleeve 36 and the drying cylinder 3 are in a linear relative sliding fit to ensure the stability of the opening and closing process. The sliding sleeve 36 moves upward to contact the upper limit convex ring 31 to form an upper stop and complete the circumferential sealing of the opening of the placement cavity 34 to reduce the gas short-circuit channel caused by the unsealed opening before and after replacement.

[0041] like Figure 3 and Figure 7As shown, a groove 33 is provided along the axis on the back of the drying cylinder 3, and a protrusion 361 is provided on the rear side of the inner wall of the sliding sleeve 36. The protrusion 361 slides inside the groove 33. The cooperation between the groove 33 and the protrusion 361 is used to guide the sliding sleeve 36 to limit the sliding sleeve 36 to move only along the axial direction of the drying cylinder 3 and to suppress the circumferential rotation of the sliding sleeve 36 relative to the drying cylinder 3. The length of the groove 33 and the position of the limiting protrusion ring are used to determine the opening and closing stroke range of the sliding sleeve 36. The embedded sliding relationship between the groove 33 and the protrusion 361 is used to improve the positioning accuracy of the sliding sleeve 36 during the opening and closing process to reduce the phenomenon of insufficient sealing caused by sway.

[0042] like Figure 6 and Figure 7 As shown, a boss 362 is provided on the outer side of the sliding sleeve 36, and a pressing block 37 is slidably installed on the inner side of the boss 362. The surface of the pressing block 37 near the sliding sleeve 36 has an arc surface adapted to the filter cartridge 35. The height of the pressing block 37 is the same as that of the placement cavity 34. The boss 362 is used to accommodate the pressing block 37 and the fixing bolt 371 assembly to provide lateral limiting and surface contact clamping for the filter cartridge 35 when the position of the sliding sleeve 36 changes. The arc surface of the pressing block 37 is used to form a close contact with the outer circular surface of the filter cartridge 35 to press the filter cartridge 35 against the stepped support surface 341 and eliminate gaps to reduce gas bypass in the working state. The height of the pressing block 37 is the same as that of the placement cavity 34 to form a reverse support for the sliding sleeve 36 after the pressing block 37 enters the placement cavity 34 to prevent the sliding sleeve 36 from falling off under vibration conditions.

[0043] like Figure 6 and Figure 7 As shown, two fixing bolts 371 are symmetrically arranged on the side of the extrusion block 37 away from the center of the filter cylinder 35. Both fixing bolts 371 pass through the boss 362, and the ends of the two fixing bolts 371 are connected to connecting rods 38, which are located outside the boss 362. A spring 39 is sleeved on the surface of the fixing bolt 371 and is located inside the boss 362. The spring 39 applies a pushing force to the extrusion block 37 in the direction of the center of the sliding sleeve 36. The fixing bolts 371 are used to provide linear guidance for the extrusion block 37 and form a parallel sliding pair within the boss 362 to ensure the smooth movement of the extrusion block 37. The connecting rod 38 is used to pull the fixing bolt 371 from the outside during the replacement operation, thereby moving the squeezing block 37 away from the filter cartridge 35 to release the clamping force and expose the placement cavity 34; the spring 39 is used to provide a continuous preload force to push the squeezing block 37 towards the center of the sliding sleeve 36 during operation, so that the squeezing block 37 and the filter cartridge 35 maintain reliable surface contact and maintain clamping stability when the equipment vibrates and the temperature changes; the combination of the fixing bolt 371, the spring 39 and the connecting rod 38 is used to simplify the loading and unloading process of the filter cartridge 35 to meet the relevant technical requirements for the ease of maintenance of the drying unit.

[0044] like Figure 1 and Figure 2As shown, a pressure gauge 4 is installed on the surface of the L-shaped telescopic pipe 2 connected to the bottom of the air inlet pipe 11. The pressure gauge 4 is used to detect the pressure of the gas inside the equipment. The pressure gauge 4 is used to provide real-time indication of the pressure status of the sampling channel after the device is connected to the equipment to be monitored, so as to confirm the working status of the pump body 14 and the sampling sealing on site. The reading of the pressure gauge 4, combined with the temperature parameter at the end of the equipment, is used to calculate the density of SF6 gas to provide a reference for the joint evaluation of trace moisture and density. The pressure gauge 4 is installed on the surface of the L-shaped telescopic pipe 2 to facilitate on-site observation and reduce the difficulty of reading caused by the equipment casing.

[0045] The working principle of this utility model is as follows:

[0046] First, connect the device to the device under test. Adjust the distance between the two L-shaped telescopic tubes 2 according to the reserved hole on the device, and lock them in place with nuts. Then connect the connector 21 to the hole on the device. Start the pump body 14 to extract SF6 gas and transport it upward. After passing through the micro-moisture detection module 1, the gas continues to rise and is dried by the drying cylinder 3 before flowing back into the electrical equipment. The micro-moisture sensor built into the micro-moisture detection module 1 detects the gas passing through it. The detected signal is transmitted to the terminal through the wireless transmission module 13. This structure can control the distance between the L-shaped telescopic tubes 2 and the device docking hole by adjusting them. It also facilitates the disassembly and installation of the device, improving its practicality.

[0047] After gas monitoring, it can be dried through the drying cylinder 3 to reduce its moisture content. Regular replacement of the desiccant is necessary; therefore, a consistent drying cylinder 3 is provided for easy desiccant replacement. The desiccant is filled into the filter cylinder 35. During installation, the filter cylinder 35 is directly placed into the placement cavity 34. The filter cylinder 35 and the internal cavity of the placement cavity 34 have the same dimensions. After placement, the inlet and outlet of the placement cavity 34 can be sealed, allowing gas to flow only through the filter cylinder 35. Then, the sliding sleeve 36 is moved up, and the spring force of the spring 39 causes the extrusion block 37 to enter the placement cavity. The inner side of 34 contacts the surface of the filter cartridge 35, which can limit the filter cartridge 35 and prevent misalignment. At the same time, since the thickness of the extrusion block 37 is consistent with the height of the placement cavity 34, the extrusion block 37 can support the sliding sleeve 36 after entering, preventing it from falling off. The cooperation between the protrusion 361 and the sliding groove 33 can ensure the fixed position of the sliding sleeve 36, so that it can only slide in the vertical direction. Conversely, when replacing, the extrusion block 37 can be pulled outward with the connecting rod 38, and then the sliding sleeve 36 can be lowered to expose the placement cavity 34, so as to facilitate the removal and replacement of the filter cartridge 35.

[0048] The above description is merely a preferred embodiment of this utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model. Structures, devices, and operating methods not specifically described or explained in this utility model, unless otherwise specified or limited, shall be implemented using conventional methods in the field.

Claims

1. An SF6 gas micro-moisture density monitoring device, comprising a micro-moisture detection module (1), characterized in that: The micro-water detection module (1) is provided with an exhaust pipe (12) at the top and an air inlet pipe (11) at the bottom. Both the air inlet pipe (11) and the exhaust pipe (12) are equipped with L-shaped telescopic pipes (2) at their ends. The L-shaped telescopic pipes (2) are provided with connectors (21) at their ends. The connectors (21) are connected to the device to be monitored. The exhaust pipe (12) is provided with a drying cylinder (3). The detected gas flows back into the equipment through the drying cylinder (3). A placement cavity (34) is provided above the surface of the drying cylinder (3). One side of the placement cavity (34) is open. A stepped support surface (341) is provided at the bottom of the placement cavity (34). The placement cavity (34) contains a filter cartridge (35), which is placed in the flow channel inside the drying cylinder (3). The filter cartridge (35) is filled with a high-efficiency desiccant.

2. The SF6 gas micro-moisture density monitoring device according to claim 1, characterized in that: The surface of the air inlet pipe (11) is provided with a pump body (14), which is used to transport gas. The outside of the micro water detection module (1) is provided with a wireless transmission module (13), and multiple wireless transmission modules (13) transmit the detection signal to the computer terminal.

3. The SF6 gas micro-moisture density monitoring device according to claim 1, characterized in that: The placement cavity (34) is provided with tapered holes at both the top and bottom, and the end of the tapered hole closer to the filter cylinder (35) is larger than the other end; An upper limit ring (31) is provided above the surface of the drying cylinder (3), and a lower limit ring (32) is provided below the surface of the drying cylinder (3).

4. The SF6 gas micro-moisture density monitoring device according to claim 3, characterized in that: A sliding sleeve (36) is vertically slidably installed on the surface of the drying cylinder (3), and the sliding sleeve (36) moves upward to seal the opening of the placement cavity (34).

5. The SF6 gas micro-moisture density monitoring device according to claim 4, characterized in that: The back of the drying cylinder (3) is provided with a groove (33) along the axis, and the inner wall of the sliding sleeve (36) is provided with a protrusion (361), which slides inside the groove (33).

6. The SF6 gas micro-moisture density monitoring device according to claim 5, characterized in that: A boss (362) is provided on the outer side of the sliding sleeve (36), and an extrusion block (37) is slidably installed on the inner side of the boss (362). The surface of the extrusion block (37) near the sliding sleeve (36) is provided with an arc surface that is compatible with the filter cylinder (35). The height of the extrusion block (37) is consistent with that of the placement cavity (34).

7. The SF6 gas micro-moisture density monitoring device according to claim 6, characterized in that: The extrusion block (37) is symmetrically provided with fixing bolts (371) on the side away from the center of the filter cylinder (35). Both fixing bolts (371) pass through the boss (362). The ends of the two fixing bolts (371) are connected to connecting rods (38), which are placed outside the boss (362). A spring (39) is fitted on the surface of the fixing bolt (371). The spring (39) is placed inside the boss (362). The spring (39) applies a thrust to the pressing block (37) in the direction of the center of the sliding sleeve (36).

8. The SF6 gas micro-moisture density monitoring device according to claim 1, characterized in that: A pressure gauge (4) is installed on the surface of the L-shaped telescopic pipe (2) connected to the bottom of the air inlet pipe (11). The pressure gauge (4) is used to detect the pressure of the gas inside the equipment.

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