R290 detection device for laboratory

Abstract

The application provides an R290 detection device for a laboratory, which comprises a multilayer sintered metal mesh cover, a ring flange and a bottom plate. The multilayer sintered metal mesh cover comprises at least three layers of sintered metal meshes with different pore sizes from inside to outside, and the central pore size is 0.038mm to 0.045mm. The ring flange is circumscribed on the outer edge of the multilayer sintered metal mesh cover, and is provided with a positioning tenon and a first screw hole. The bottom plate is provided with a positioning groove and a second screw hole, the positioning tenon is inserted into the positioning groove, and the bottom plate is screwed through a bolt, so as to form a containing space. The combustible gas generated by the detected module enters the containing space through a pipeline and is ignited by a striking device. The application realizes flame quenching by using a microporous structure, and has the advantages of safe consumption of R290, low cost and fast response.

Description

Technical Field

[0001] This invention relates to the field of safety testing technology for refrigeration and air conditioning systems, and more specifically, to an R290 testing device for use in laboratories. Background Technology

[0002] R290 (propane), as a natural refrigerant, has zero ozone depletion potential (ODP) and extremely low global warming potential (GWP), attracting increasing attention in the refrigeration and air conditioning industry. However, R290 is highly flammable, forming an explosive mixture when its volume fraction in air is between 2.1% and 9.5%. This characteristic severely limits the research, development, and widespread application of R290 refrigeration systems.

[0003] In the research and development of refrigeration and air conditioning systems, extensive testing of R290 modules is required in laboratory settings. If an R290 leak occurs in the laboratory and reaches a flammable or explosive concentration, it can easily lead to a fire or even an explosion. Current technology typically uses R290 concentration sensors to monitor the R290 concentration in the laboratory. When the sensor detects an excessive concentration, the system issues an alarm and initiates safety measures such as ventilation or shutdown. However, this existing solution has significant shortcomings. First, the procurement cost of high-precision R290 concentration sensors is very high, increasing the equipment investment in the laboratory. Second, these sensors require regular calibration to ensure accuracy, resulting in high operating and maintenance costs. More importantly, the existing technology can only detect concentration and issue alarms; it cannot actively and safely dissipate leaked R290 gas. The leaked gas continues to accumulate in the laboratory, posing a significant safety hazard.

[0004] Therefore, how to provide a low-cost detection device that can effectively detect R290 concentration and promptly and safely consume leaked R290 has become a technical problem that urgently needs to be solved by those skilled in the art.

[0005] In view of this, the present invention provides an R290 detection device for laboratory use. Summary of the Invention

[0006] This invention provides an R290 detection device for laboratory use, which at least solves the problems of high cost and inability to actively and safely consume leaked R290 in the prior art.

[0007] This invention provides an R290 testing device for use in a laboratory, comprising: A multi-layer sintered metal mesh cover, wherein the multi-layer sintered metal mesh cover comprises at least three layers of sintered metal mesh with different pore sizes from the inside to the outside, the pore size of the sintered metal mesh closer to the center is smaller, and the pore size of the sintered metal mesh located at the very center is 0.038mm to 0.045mm. A circumferential flange face is externally connected to the outer edge of the multilayer sintered metal mesh cover. A plurality of positioning tenons and first screw holes are provided along the trajectory of the circumferential flange face. The protruding direction of the positioning tenons is opposite to the protruding direction of the multilayer sintered metal mesh cover. A base plate is provided with several positioning grooves and a second screw hole. The positioning tenon of the circumferential flange surface is inserted into and aligned with the positioning groove. The circumferential flange surface is bolted to the base plate, so that the multi-layer sintered metal mesh cover is tightly connected to the base plate to form an accommodating space. A detection module, wherein the combustible gas generated by the detection module is guided through a pipe to the surface of the multi-layer sintered metal mesh cover, and enters the containment space through the mesh cover; An ignition device is provided in the containment space for igniting combustible gas entering the containment space.

[0008] Preferably, the multilayer sintered metal mesh cover comprises, from the inside out: an inner contact layer, a support layer, a fire-resistant layer, a transition layer, and an outermost layer.

[0009] Preferably, the inner contact layer has a mesh size of 60 to 80 and an aperture of 0.18 mm to 0.27 mm; the support layer has a mesh size of 100 to 150 and an aperture of 0.106 mm to 0.15 mm; the fire-retardant layer has a mesh size of 325 to 400 and an aperture of 0.038 mm to 0.045 mm; the transition layer has a mesh size of 100 to 150 and an aperture of 0.106 mm to 0.15 mm; and the outermost layer has a mesh size of 40 to 60 and an aperture of 0.28 mm to 0.45 mm.

[0010] Preferably, the total thickness of the multilayer sintered metal mesh cover is 4mm to 6mm.

[0011] Preferably, the base plate is a solid flange base.

[0012] Preferably, the multilayer sintered metal mesh cover is hemispherical, cubic, or cylindrical.

[0013] Preferably, the circumferential flange face is welded to the outer edge of the multilayer sintered metal mesh cover.

[0014] Preferably, the ignition device is a timed ignition module.

[0015] Preferably, the module being tested is an R290 module.

[0016] Preferably, when the temperature sensor detects the temperature within the containment space, the temperature sensor is electrically connected to the module being detected via a conduit passing through the base plate.

[0017] Preferably, one end of the pipe is connected to the module being tested, and the other end is close to the outer surface of the multi-layer sintered metal mesh cover.

[0018] This invention discloses an R290 detection device for a laboratory. Leaking gas from the module being tested (R290 module) is guided through a pipeline into the containment space of a multi-layered sintered metal mesh cover, where it is actively ignited using a timed ignition device. As the flame passes through the gradient structure of the multi-layered sintered metal mesh, the pore size of the core flame-retardant layer (0.038 mm to 0.045 mm) is much smaller than the maximum experimental safety gap (MESG) of R290 (approximately 0.92 mm), ensuring the flame is completely quenched within the metal mesh and preventing it from propagating to the outside and igniting other equipment. Simultaneously, the R290 burns safely inside the detection device, actively and safely consuming the leaking R290. When a temperature sensor detects a rapid temperature change, it can issue an alarm and shut down the R290 module, achieving integrated functions of detection, alarm, and safe consumption. This device employs a physical quenching principle, eliminating reliance on expensive concentration sensors and complex control systems, significantly reducing costs and improving safety. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0020] Figure 1 This is a schematic diagram of an R290 testing device for a laboratory provided in an embodiment of this application.

[0021] Figure 2 yes Figure 1 A magnified view of a multi-layer sintered metal mesh cover.

[0022] Explanation of reference numerals in the attached figures: 1. Multi-layer sintered metal mesh cover 11 Outermost layer 12 Transition Layer 13 Fire-resistant layer 14 Support layer 15 Inner Contact Layer 2. Base plate 21 Positioning slots 22 Second screw hole 3. Circumferential flange face 31. Positioning tenon 32 First screw hole 4 bolts 5. Ignition device 6. Modules under test 7 Pipelines 8 Temperature Sensor Detailed Implementation

[0023] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0024] The use of terms such as "first," "second," and similar terms in the specific description does not indicate any order, quantity, or importance, but is merely used to distinguish different components. Furthermore, in the description of this invention, terms such as "upper," "lower," etc., indicate orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention.

[0025] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features in different embodiments can be combined with each other.

[0026] Figure 1 This is a schematic diagram of an R290 testing device for a laboratory provided in an embodiment of this application. Figure 2 yes Figure 1 A magnified view of a multi-layer sintered metal mesh cover. (See image.) Figure 1 and 2As shown, the R290 testing device for laboratory use of the present invention includes a multi-layer sintered metal mesh cover 1, a circumferential flange surface 3, a base plate 2, a test module 6, and an ignition device 5. The multi-layer sintered metal mesh cover 1 comprises at least three layers of sintered metal mesh with different apertures from the inside out. The aperture of the sintered metal mesh closer to the center is smaller, and the aperture of the sintered metal mesh located at the very center is 0.038 mm to 0.045 mm. The circumferential flange surface 3 is connected to the outer edge of the multi-layer sintered metal mesh cover 1, and a plurality of positioning tenons 31 and first screw holes 32 are provided along the trajectory of the circumferential flange surface 3. The protrusion direction of the positioning tenons 31 is opposite to the protrusion direction of the multi-layer sintered metal mesh cover 1. The base plate 2 is provided with several positioning grooves 21 and second screw holes 22. The positioning tenon 31 of the circumferential flange surface 3 is inserted into the positioning groove 21. The circumferential flange surface 3 is screwed to the base plate 2 by bolts 4, so that the multi-layer sintered metal mesh cover 1 and the base plate 2 are tightly connected to form an accommodating space. The combustible gas generated by the detection module 6 is guided to the surface of the multi-layer sintered metal mesh cover 1 through a pipe 7, so that at least part of the combustible gas enters the accommodating space through the mesh cover. The ignition device 5 is set in the accommodating space to ignite the combustible gas that enters the accommodating space. The technical effect of this specific embodiment is that: through the insertion and cooperation of the positioning tenon 31 and the positioning groove 21 and the fastening connection of the bolts 4, the precise assembly and sealing of the multi-layer sintered metal mesh cover 1 and the base plate 2 are achieved, ensuring that the combustible gas will not leak from the joint. The gas leaked by the detection module 6 is actively guided into the accommodating space and actively ignited by the ignition device 5, realizing the whole process control from the collection of leaked gas to safe combustion. The microporous structure of the central sintered metal mesh can effectively quench the flame, prevent backfire, and ensure the safety of the external environment of the device.

[0027] In a preferred embodiment, the multilayer sintered metal mesh cover 1 comprises, from the inside out: an inner contact layer 15, a support layer 14, a flame-retardant layer 13, a transition layer 12, and an outermost layer 11. The technical advantage of this specific embodiment lies in the gradient layered structure design, which gives the mesh cover a gradually changing mesh size from the inside out. The inner contact layer 15 is used for direct contact with the internal gas environment; the support layer 14 provides structural support for the fine flame-retardant layer 13, preventing its deformation under pressure impact; the transition layer 12 achieves a smooth transition in pore size; and the outermost layer 11 serves as the final protective and heat dissipation layer, achieving an optimized balance between flame-retardant performance, structural strength, and air permeability.

[0028] In a preferred embodiment, the inner contact layer 15 has a mesh size of 60 to 80 and an aperture of 0.18 mm to 0.27 mm; the support layer 14 has a mesh size of 100 to 150 and an aperture of 0.106 mm to 0.15 mm; the flame-retardant layer 13 has a mesh size of 325 to 400 and an aperture of 0.038 mm to 0.045 mm; the transition layer 12 has a mesh size of 100 to 150 and an aperture of 0.106 mm to 0.15 mm; and the outermost layer 11 has a mesh size of 40 to 60 and an aperture of 0.28 mm to 0.45 mm. The technical advantage of this specific embodiment is that the flame-retardant layer 13 has extremely small apertures, effectively quenching the flame generated by R290 combustion. The inner contact layer 15 and the outermost layer 11 have relatively large apertures, ensuring good air permeability and allowing the heat generated by combustion to dissipate in a timely manner. The support layer 14 and the transition layer 12 serve to transition and reinforce the structure.

[0029] In a preferred embodiment, the total thickness of the multilayer sintered metal mesh cover 1 is 4mm to 6mm. The technical advantage of this specific embodiment is that this thickness range comprehensively considers both flame-retardant effect and heat dissipation performance. Too little thickness may result in incomplete flame quenching, while too much thickness will affect heat dissipation and increase costs. Within this thickness range, it can be ensured that the flame is completely quenched as it passes through the mesh cover, while simultaneously guaranteeing good heat conduction and air permeability.

[0030] In a preferred embodiment, the base plate 2 is a solid flange base. The technical advantage of this specific embodiment is that the solid flange base provides sufficient strength and stability to firmly support the entire detection device. Simultaneously, the solid structure has no gaps, structurally ensuring that the bottom will not become a channel for flame propagation, significantly improving the safety and sealing of the device.

[0031] In a preferred embodiment, the shape of the multilayer sintered metal mesh cover 1 is defined, and it can be hemispherical, cubic, or cylindrical. The technical advantage of this specific embodiment is that different shaped mesh covers are suitable for different application scenarios. Hemispherical structures have high strength and uniform stress distribution; cubic shapes facilitate side-by-side placement and space utilization; cylindrical shapes have mature manufacturing processes and lower costs. Users can choose the most suitable shape according to laboratory space and actual needs.

[0032] In a preferred embodiment, the circumferential flange face 3 is welded to the outer edge of the multilayer sintered metal mesh cover 1. The technical advantage of this specific embodiment is that the welded connection achieves a strong bond between the circumferential flange face 3 and the multilayer sintered metal mesh cover 1, forming a single integral structure. The welded joint has high strength and high sealing performance, capable of withstanding pressure wave impacts that may occur during flame quenching, while preventing flame leakage from the connection point, thus improving the reliability of the device.

[0033] In a preferred embodiment, the ignition device 5 is a timed ignition module. The technical advantage of this specific embodiment is that the timed ignition module can automatically perform ignition operations according to a preset time interval (e.g., igniting once every 30 seconds to 2 minutes), ensuring that when the leaked R290 gas reaches the explosive concentration, it can be ignited in time and safely consumed, avoiding the risk of gas accumulation caused by continuous micro-leakage, and realizing the automated operation of the device.

[0034] In a preferred embodiment, the module being detected, 6, is an R290 module. The technical advantage of this specific embodiment is that the device is specifically designed for R290 (propane) refrigerant modules, and the pore size of its core flame arrestor layer is optimized based on the maximum experimental safe clearance MESG value of R290 (approximately 0.92 mm). This allows for the most effective quenching of the flame generated by R290 combustion, achieving safe detection and consumption of leaked gas from the R290 module.

[0035] In a preferred embodiment, when the temperature sensor 8 detects the temperature within the containment space, the temperature sensor 8 is electrically connected to the monitored module 6 via a conduit passing through the base plate 2. The temperature sensor 8 can detect rapid temperature changes, triggering an alarm signal. The temperature sensor 8 connects to the monitored module 6 and shuts down the monitored module 6 (R290 module), cutting off the source of leakage at its source and thus improving safety.

[0036] In a preferred embodiment, one end of the pipe 7 is connected to the module being tested 6, and the other end is close to the outer surface of the multilayer sintered metal mesh cover 1. The technical advantage of this specific embodiment is that by guiding the leaked gas through the pipe 7 to a position close to the outer surface of the multilayer sintered metal mesh cover 1, the leaked gas can be efficiently drawn in or diffused into the internal containment space of the multilayer sintered metal mesh cover 1, reducing the disorderly diffusion of gas to other areas of the test chamber and improving detection and consumption efficiency.

[0037] The specific embodiments of the present invention are as follows: The following is in conjunction with the appendix Figures 1 to 2 This invention provides a complete specific implementation scheme for the most important product form of the present invention. This specific implementation scheme integrates the preferred technical features of the above specific embodiments, constituting a complete technical solution for a laboratory R290 testing device with optimal performance and the widest applicability.

[0038] like Figure 1 As shown in the figure, this specific embodiment provides an R290 detection device for laboratory use. This device is mainly used to detect leaks and ensure safe consumption of the R290 module (i.e., the module under test 6) in the laboratory environment of scroll compressors and refrigeration and air conditioning systems, so as to prevent the accumulation of leaked R290 gas and the occurrence of fire or explosion accidents after reaching the concentration of combustion and explosion.

[0039] The laboratory R290 testing device of this specific implementation scheme includes five main components: a multi-layer sintered metal mesh cover 1, a base plate 2, a circumferential flange face 3, an ignition device 5, and a pipe 7 for guiding combustible gas.

[0040] The multi-layer sintered metal mesh cover 1 is made of 316L stainless steel. 316L stainless steel is an ultra-low carbon austenitic stainless steel with excellent corrosion resistance and good processing performance. More importantly, it has a high thermal conductivity, enabling it to rapidly conduct flame heat to the entire mesh cover and dissipate it into the environment, preventing localized overheating. In this specific embodiment, the multi-layer sintered metal mesh cover 1 is preferably hemispherical in shape. The hemispherical structure has good mechanical properties, ensuring uniform stress distribution when subjected to pressure waves generated by internal flame combustion, and reducing the likelihood of deformation or breakage due to stress concentration. Simultaneously, the hemispherical mesh cover, when combined with the base plate 2, forms a large volumetric space, which is beneficial for the collection of combustible gases and safe combustion.

[0041] like Figure 2 As shown, the multilayer sintered metal mesh cover 1 comprises five layers of sintered metal mesh with a gradient structure from the inside out: an inner contact layer 15, a support layer 14, a flame-retardant layer 13, a transition layer 12, and an outermost layer 11. The inner contact layer 15 has a mesh size of 60 to 80 mesh, corresponding to an aperture of 0.18 mm to 0.27 mm. The support layer 14 has a mesh size of 100 to 150 mesh, with an aperture of 0.106 mm to 0.15 mm. The flame-retardant layer 13 is the core functional layer of this device, with a mesh size of 325 to 400 mesh and an aperture of 0.038 mm to 0.045 mm. The transition layer 12 has a mesh size of 100 to 150 mesh, with an aperture of 0.106 mm to 0.15 mm. The outermost layer 11 has a mesh size of 40 to 60 mesh, with an aperture of 0.28 mm to 0.45 mm. The total thickness of the five-layer composite structure is 4mm to 6mm, and preferably 5mm in this specific embodiment. Testing has shown that a total thickness of 5mm ensures that, under continuous combustion, the flame is completely quenched inside the mesh cover, and the outer surface temperature remains below the ignition point of R290 (approximately 450°C), preventing it from becoming an external ignition source.

[0042] The circumferential flange face 3 is made of 316L stainless steel and is welded to the outer edge of the multi-layer sintered metal mesh cover 1 by argon arc welding. Multiple positioning tenons 31 and multiple first screw holes 32 are provided along the circumferential trajectory of the circumferential flange face 3. The positioning tenons 31 are protruding cylindrical structures, and their protrusion direction is opposite to the protrusion direction of the multi-layer sintered metal mesh cover 1, that is, protruding towards the base plate 2.

[0043] The base plate 2 is a solid flange base, also made of 316L stainless steel. The upper surface of the base plate 2 has multiple positioning grooves 21 and multiple second screw holes 22. The positioning grooves 21 are circular recesses, their number, position, and size matching the positioning tenons 31 on the circumferential flange face 3. When the multi-layer sintered metal mesh cover 1 is assembled with the base plate 2, the positioning tenons 31 are inserted into the corresponding positioning grooves 21, achieving precise circumferential and radial positioning. The second screw holes 22 correspond to the first screw holes 32 on the circumferential flange face 3 and are used to install bolts 4. The base plate 2 is a solid structure with a thickness greater than 20mm, capable of withstanding the pressure wave impact generated by combustion without deformation.

[0044] The ignition device 5 is disposed in the receiving space formed by the multi-layer sintered metal mesh cover 1 and the base plate 2. In this specific embodiment, the ignition device 5 is a timed ignition module, which automatically performs ignition operation according to a preset time interval (e.g., igniting once every 30 seconds to 2 minutes).

[0045] One end of the pipe 7 is connected to the module 6 being tested (i.e., the R290 module), and the other end is close to the outer surface of the multilayer sintered metal mesh cover 1. When the R290 module leaks, the leaked R290 gas is guided through the pipe 7 to the vicinity of the outer surface of the multilayer sintered metal mesh cover 1, and enters the containment space inside the multilayer sintered metal mesh cover 1 by self-absorption or diffusion.

[0046] The working process and principle of the laboratory R290 testing device in this specific implementation scheme are as follows: When the tested module 6 (R290 module) experiences an R290 leak, the leaked gas is guided through pipe 7 to the outer surface of the multi-layer sintered metal mesh cover 1. Due to the good air permeability of the multi-layer sintered metal mesh cover 1, the R290 gas passes through the outermost layer 11, transition layer 12, flame-retardant layer 13, support layer 14, and inner contact layer 15, and enters the containment space formed by the multi-layer sintered metal mesh cover 1 and the base plate 2.

[0047] The ignition device 5 generates an electric spark within the containment space at preset time intervals (e.g., once every 30 seconds to 2 minutes). When the R290 gas concentration within the containment space reaches the explosive concentration (volume fraction 2.1% to 9.5%), the electric spark ignites the R290 gas, and combustion begins. The flame generated by the combustion of R290 propagates outward from the ignition point, first encountering the inner contact layer 15. The inner contact layer 15 has a pore size of 0.18 mm to 0.27 mm, providing initial resistance to flame propagation. After passing through the inner contact layer 15, the flame reaches the support layer 14, which has a pore size of 0.106 mm to 0.15 mm, further reducing the size of the flame propagation channel and significantly weakening the flame intensity.

[0048] Subsequently, the weakened flame reaches the flame arrestor layer 13. The pore size of the flame arrestor layer 13 is only 0.038 mm to 0.045 mm, far smaller than the maximum experimental safe gap MESG value of 0.92 mm for R290. According to the principle of flame quenching, when the flame attempts to pass through such a small channel, the active free radicals (such as H, O, OH, etc.) required for the combustion chain reaction collide extensively with the channel wall and become deactivated. The free radical concentration drops sharply below the critical value that cannot sustain the combustion reaction, and the flame is completely quenched. At the same time, the high thermal conductivity of 316L stainless steel allows the channel wall to rapidly absorb the heat of the flame, conduct the heat to the entire mesh cover, and dissipate it into the atmosphere.

[0049] After being quenched by the flame arrestor layer 13, the flame is extinguished, and only the high-temperature gas flow and pressure wave continue to propagate outward. When the high-temperature gas flow exits the mesh cover through the transition layer 12 and the outermost layer 11, the gas temperature drops significantly due to the heat dissipation effect of the mesh cover, and is below the ignition point of R290 upon exiting, thus preventing the ignition of any substances outside the mesh cover. The R290 gas burns safely inside the detection device, actively and safely consuming leaked R290 and preventing the accumulation of R290 gas in the test chamber.

[0050] When the temperature sensor 8, located near the inner side of the fire-resistant layer 13, detects a rapid temperature change (e.g., a temperature change rate between 40°C / s and 60°C / s), it triggers an alarm signal. The temperature sensor 8 connects to the module under test 6 and shuts down the module under test 6 (R290 module), cutting off the leakage of the module under test 6 at the source.

[0051] In this specific implementation scheme, the R290 testing device used in the laboratory maintains a tight seal at the joint between the circumferential flange face 3 and the base plate 2 throughout the entire operation due to the tightening of the bolts 4 and the precise fit between the positioning tenon 31 and the positioning groove 21, preventing any leakage of flame or high-temperature gas. The solid structure of the base plate 2 ensures that there is absolutely no path for flame propagation at the bottom.

[0052] In summary, the laboratory R290 detection device of this invention achieves efficient collection, active ignition, and safe combustion consumption of leaked gas from R290 modules, ensuring that the flame does not spread outside the device, thereby protecting the safety of other equipment and personnel within the laboratory. Compared with existing technologies that rely solely on expensive concentration sensors, this device significantly reduces costs, eliminates the need for periodic calibration, and integrates detection, alarm, and safe combustion functions, representing a significant technological advancement.

[0053] The above description, in conjunction with specific optional embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. An R290 testing device for use in a laboratory, characterized in that, include: A multilayer sintered metal mesh cover (1) comprises at least three layers of sintered metal mesh with different apertures from the inside out. The aperture of the sintered metal mesh closer to the center is smaller, and the aperture of the sintered metal mesh located at the very center is 0.038 mm to 0.045 mm. A circumferential flange surface (3) is externally connected to the outer edge of the multilayer sintered metal mesh cover (1). A plurality of positioning tenons (31) and first screw holes (32) are provided along the trajectory of the circumferential flange surface (3). The protrusion direction of the positioning tenons (31) is opposite to the protrusion direction of the multilayer sintered metal mesh cover (1). A base plate (2) is provided with several positioning grooves (21) and a second screw hole (22). The positioning tenon (31) of the circumferential flange surface (3) is inserted into the positioning groove (21). The circumferential flange surface (3) is screwed to the base plate (2) by bolts (4), so that the multilayer sintered metal mesh cover (1) is tightly connected to the base plate (2) to form an accommodating space. A detection module (6) generates combustible gas which is guided through a pipe (7) to the surface of the multilayer sintered metal mesh cover (1) and enters the containment space through the mesh cover; An ignition device (5) is provided in the containment space for igniting combustible gas entering the containment space.

2. The R290 testing device for a laboratory as described in claim 1, characterized in that, The multilayer sintered metal mesh cover (1) includes, from the inside out: an inner contact layer (15), a support layer (14), a fire-resistant layer (13), a transition layer (12), and an outermost layer (11).

3. The R290 testing device for a laboratory as described in claim 2, characterized in that, The inner contact layer (15) has a mesh size of 60 to 80 and an aperture of 0.18 mm to 0.27 mm; the support layer (14) has a mesh size of 100 to 150 and an aperture of 0.106 mm to 0.15 mm; the fire-resistant layer (13) has a mesh size of 325 to 400 and an aperture of 0.038 mm to 0.045 mm; the transition layer (12) has a mesh size of 100 to 150 and an aperture of 0.106 mm to 0.15 mm; and the outermost layer (11) has a mesh size of 40 to 60 and an aperture of 0.28 mm to 0.45 mm.

4. The R290 testing device for a laboratory as described in claim 2, characterized in that, The total thickness of the multilayer sintered metal mesh cover (1) is 4 mm to 6 mm.

5. The R290 testing device for a laboratory as described in claim 1, characterized in that, The base plate (2) is a solid flange base.

6. The R290 testing device for a laboratory as described in claim 5, characterized in that, The multi-layer sintered metal mesh cover (1) is hemispherical, cubic or cylindrical.

7. The R290 testing device for a laboratory as described in claim 1, characterized in that, The circumferential flange (3) is welded to the outer edge of the multilayer sintered metal mesh cover (1).

8. The R290 testing device for a laboratory as described in claim 1, characterized in that, The ignition device (5) is a timed ignition module, and the module being tested (6) is an R290 module.

9. The R290 testing device for a laboratory as described in claim 1, characterized in that, When the temperature sensor detects the temperature within the containment space, the temperature sensor is electrically connected to the detected module (6) via a conduit passing through the base plate (2).

10. The R290 testing device for a laboratory as described in claim 1, characterized in that, One end of the pipe (7) is connected to the module being tested (6), and the other end is close to the outer surface of the multilayer sintered metal mesh cover (1).

Images