A protective device for preventing condensation of a sampling bottle

Abstract

The application provides a protective device for sample bottle heat preservation and anti-condensation, comprising a cylinder and an end cover, the cylinder is open at both ends, and the end cover is connected with the end of the cylinder to close the cylinder; the cylinder comprises a heating layer, a heat preservation layer and a protective layer from inside to outside; the heating layer comprises a graphene modified elastic matrix and a flexible electric heating film embedded in the elastic matrix; the inner surface of the elastic matrix is integrally formed with a plurality of elastic members protruding radially inward, and the plurality of elastic members are arranged in the circumferential direction; the heating layer is curled from a sheet material, the two butt end faces in the circumferential direction are obliquely overlapped, and an elastic gap that can expand in the circumferential direction is formed; the heat preservation layer is bonded to the outer surface of the elastic matrix through a discontinuous bonding structure, the discontinuous bonding structure comprises a plurality of bonding members distributed in the circumferential direction, an unbonded area is formed between adjacent bonding members, and the unbonded area is configured to allow the heating layer and the heat preservation layer to relatively slide in the circumferential direction; and the protective layer is bonded to the outer surface of the heat preservation layer.

Description

Technical Field

[0001] This application relates to the field of industrial sampling technology, and in particular to a protective device for heat preservation and anti-condensation of sampling bottles. Background Technology

[0002] In the fields of petrochemicals, natural gas, and light hydrocarbon analysis, sampling bottles are used to collect and temporarily store volatile liquefied gas samples (such as crude oil, condensate, natural gas condensate, and light hydrocarbon samples). When operating in extremely cold environments below -20°C: on the one hand, the temperature of the sample inside the sampling bottle will drop rapidly, and heavy components (such as wax and asphaltene) may precipitate or solidify; on the other hand, if the insulation measures fail to maintain the bottle wall temperature above the dew point of the surrounding moist air, condensation will occur on the outer wall of the sampling bottle due to condensation, and moisture may seep into the bottle through the seal at the bottle opening. Simultaneously, condensation may also occur on the inner wall of the sampling bottle due to the condensation of residual moisture in the sample, severely affecting the accuracy of subsequent laboratory analysis. Therefore, in low-temperature environments, efficient synergistic control of insulation and anti-condensation measures for sampling bottles is crucial to ensuring sample integrity and testing reliability.

[0003] Existing sampling insulation devices typically include a housing, a heating element, and an insulation layer. The housing is made of metal or rigid engineering plastic and has a cylindrical cavity inside that matches the outer diameter of a standard sampling bottle. The heating element (such as a spirally wound resistance wire) is fixed to the inner wall surface of this cavity. After the sampling bottle is inserted into the cavity, it comes into contact with the heating element to achieve heat conduction. The insulation layer (such as polyurethane foam) completely covers the outside of the housing to reduce heat loss to the environment.

[0004] However, the cavity size of such insulation devices is fixed, and they can only accommodate a single size of sampling bottle. In practical applications, however, different analytical projects have varying requirements for sample volume, gas-liquid ratio, and component stability, resulting in inconsistent outer diameters of the sampling bottles used on-site. Existing insulation devices cannot adapt to this reality of multiple sizes: bottles with larger outer diameters cannot be fitted, while bottles with smaller outer diameters are prone to breakage during transport due to shaking and collisions, leading to sample leakage. Summary of the Invention

[0005] The purpose of this application is to provide a protective device for heat preservation and anti-condensation of sampling bottles, so as to achieve reliable compatibility of the same device with a variety of sampling bottles of different diameters, and simultaneously ensure its effective heat preservation and anti-condensation performance in low-temperature environments.

[0006] To address the aforementioned technical problems, this application provides the following technical solutions: The first aspect of this application provides a protective device for heat preservation and anti-condensation of sampling bottles, comprising: The cylinder has openings at both ends, and the bottom end cap is sealed to the first end of the cylinder. The cylinder comprises, from the inside out, a heating layer, a heat insulation layer, and a protective layer; The heating layer includes a graphene-modified elastic matrix and a flexible electric heating film embedded in the elastic matrix. The inner surface of the elastic matrix is ​​integrally formed with multiple elastic elements that protrude radially inward. The multiple elastic elements are arranged at intervals along the circumferential direction for radial positioning of the sampling bottle. The heating layer is formed by rolling a sheet, with its two circumferentially connected end faces at an oblique angle to form an elastic gap that can expand circumferentially. The thermal insulation layer is bonded to the outer surface of the elastic substrate by an intermittent adhesive structure, the intermittent adhesive structure comprising a plurality of adhesive members spaced apart along the circumferential direction, and an unbonded area formed between adjacent adhesive members, the unbonded area being configured to allow relative sliding between the heating layer and the thermal insulation layer in the circumferential direction; The protective layer is bonded to the outer surface of the insulation layer.

[0007] In some embodiments, a plurality of elastic elements are arranged at equal intervals along the circumferential direction, each elastic element having an arc-shaped raised structure, and the cross-sectional area gradually decreases from its fixed end connected to the elastic matrix to its free end.

[0008] In some embodiments, the two mating end faces of the heating layer overlap at a 45° angle. The device also includes an elastic sealing strip that fits onto the outer surface of the protective layer; the elastic sealing strip extends axially and is aligned with the elastic gap in the circumferential direction to cover the opening area of ​​the elastic gap and prevent external moisture from entering.

[0009] In some embodiments, the insulation layer is a hydrophobic silica aerogel composite felt with a water contact angle greater than 140° and a thermal conductivity less than 0.020 W / (m·K). The protective layer is a hydrophobic flexible material selected from any one of neoprene foam, polyurethane film, polyurethane composite fabric, or silicone rubber composite fabric.

[0010] In some embodiments, the bottom end cap is a flexible silicone sleeve bottom, and the inner surface of the flexible silicone sleeve bottom is recessed inward to form a curved limiting groove. The heating layer is located on the outside of the limiting groove in the radial direction. The limiting groove is used to provide axial support and radial positioning for the bottom of the sampling bottle. The device further includes: The first and second sealant layers are both in a continuous ring shape. The first sealant layer forms a sealing connection between the inner surface of the flexible silicone sleeve bottom and the end face of the first end of the cylinder, and the first sealant layer is located on the outer side of the heating layer in the radial direction; The second sealant layer fills the corner area between the outer peripheral sidewall of the first end of the cylinder and the outer surface of the flexible silicone sleeve bottom, so that the two form a sealed connection.

[0011] In some embodiments, the flexible electric heating film has serpentine, equidistantly spaced metal heating traces inside; the line width, line spacing, and number of loops of the metal heating traces are configured such that the equivalent resistance of the flexible electric heating film is 2.5Ω to 8.0Ω; the flexible electric heating film is used to connect to a 5V DC power supply.

[0012] In some embodiments, it also includes: Negative temperature coefficient thermistors, wired control boxes, and over-temperature protection switches; The negative temperature coefficient thermistor is connected to the elastic matrix and configured to collect the temperature signal of the heating layer or the sampling bottle; The wired control box integrates a reverse connection protection component, a DC-DC boost converter, a digital temperature control module, and a switching device controlled by the digital temperature control module. The first end of the reverse connection protection element is used to connect to the positive terminal of the DC power supply, the second end of the reverse connection protection element is electrically connected to the power input terminal of the DC boost converter and the first end of the switching device, and the boost output terminal of the DC boost converter is electrically connected to the power supply terminal of the digital temperature control module. The digital temperature control module is connected to the negative temperature coefficient thermistor signal, and the control signal output terminal of the digital temperature control module is electrically connected to the control terminal of the switching device; the digital temperature control module is configured to control the switching device to turn on and off according to the temperature signal collected by the negative temperature coefficient thermistor, so as to enable the flexible electric heating film to perform closed-loop constant temperature control. The second end of the switching device is electrically connected to the flexible electric heating film through the over-temperature protection switch, and the over-temperature protection switch is in thermal contact with the flexible electric heating film; the over-temperature protection switch is configured to disconnect the power supply circuit of the flexible electric heating film when the temperature of the flexible electric heating film exceeds its preset action threshold.

[0013] In some embodiments, the wired control box also integrates an energy limiting protection module, which includes a fuse, a positive temperature coefficient self-resetting current limiting thermistor, and an overvoltage clamping device. The second terminal of the switching device is connected in series with the fuse, the positive temperature coefficient self-resetting current-limiting thermistor and the over-temperature protection switch. The first end of the overvoltage clamping device is electrically connected to the connection node between the fuse and the positive temperature coefficient self-recovering current-limiting thermistor, and its second end is electrically connected to the negative terminal of the DC power supply.

[0014] In some embodiments, the wired control box is a waterproof junction box constructed through the coordinated use of materials and sealing structures, with waterproof cable connectors provided at its power input and output ends respectively; The terminals of the flexible electric heating film, the leads of the negative temperature coefficient thermistor, and the lead holes of the cylinder are all sealed with flame-retardant silicone rubber potting. The circumferential edges of the elastic matrix are sealed with silicone rubber to form a waterproof seal.

[0015] In some embodiments, the protective device includes three sizes: small, medium, and large. The inner diameter of the heating layer of the small-sized protective device is 35 mm, which is used to adapt to the sampling bottle with an outer diameter of 35~45 mm. The inner diameter of the heating layer of the medium-sized protective device is 45 mm, which is used to fit the sampling bottle with an outer diameter of 45~55 mm. The inner diameter of the heating layer of the larger model of the protective device is 55 mm, which is used to fit the sampling bottle with an outer diameter of 55~65 mm.

[0016] Compared to existing technologies, the protective device for heat preservation and anti-condensation of sampling bottles provided in this application utilizes multiple elastic elements for radial positioning of the sampling bottle: when a sampling bottle with a relatively small outer diameter (e.g., 35mm) is inserted, the multiple elastic elements are moderately compressed, working together from all sides to center the bottle, effectively preventing the bottle from colliding with the hard inner wall during transport and breaking or leaking. When a sampling bottle with a relatively large outer diameter (e.g., 45mm) is inserted, the elastic elements are compressed to be flush with the inner surface of the elastic matrix, while the beveled overlap gaps of the heating layer's rolled-up sheet passively open, increasing the adaptability of the heating layer's inner diameter; during this process, the unbonded area between the heating layer and the insulation layer allows for circumferential relative sliding, effectively releasing deformation stress and preventing the insulation layer from thinning, cracking, or detaching due to stretching, thereby ensuring its structural integrity and long-term thermal insulation performance. Therefore, a single device of the same specification can safely adapt to various sampling bottle sizes, significantly improving the portability and equipment versatility for field operations.

[0017] The flexible electric heating film embedded in the heating layer generates heat when energized. This heat is rapidly transferred to the sampling bottle wall via a graphene-modified, highly thermally conductive elastic matrix and its integrally molded elastic components, maintaining the bottle wall temperature stably within a preset range (e.g., 5-15℃). This ensures the bottle wall temperature remains consistently above the dew point temperature of typical outdoor air, effectively suppressing condensation. The insulation layer uses a low thermal conductivity material to effectively block heat intrusion from the external low-temperature environment, significantly reducing heating power consumption and ensuring temperature control stability. The outer protective layer resists external mechanical damage and environmental corrosion, ensuring the internal heating and insulation layers are unaffected by external interference. This enables the long-term effective operation of the thermal management system, preventing insulation failure and temperature instability due to shell damage, thus avoiding the risk of condensation. Attached Figure Description

[0018] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application are illustrated by way of example and not limitation, with the same or corresponding reference numerals denoteing the same or corresponding parts, wherein: Figure 1 A schematic diagram of the structure of the protective device's cylinder and wired control box is shown. Figure 2 A schematic diagram of the structure of the protective device cylinder and the second sealing layer of this application is shown. Figure 3 A schematic diagram of the heating layer and discontinuous bonding structure of the protective device of this application is shown. Figure 4 A schematic diagram of the structure of the end cap of the protective device of this application is shown. Figure 5 A schematic cross-sectional view of the end cap of the protective device of this application is shown; Figure 6 A schematic diagram of the electrical control system of the protection device of this application is shown.

[0019] Explanation of icon numbers: 1. Cylinder body; 11. Heating layer; 111. Butt joint face; 12. Insulation layer; 13. Protective layer; 14. Elastic element; 15. Intermittent bonding structure; 2. Bottom end cap; 21. Limiting groove; 22. First sealing layer; 23. Second sealing layer; 3. Elastic sealing strip; 4. Wired control box; 41. DC power supply; 42. Reverse connection protection element; 43. DC boost converter; 44. Digital temperature control module; 45. Negative temperature coefficient thermistor; 46. Switching device; 47. Energy limiting protection module; 48. Over-temperature protection switch; 49. Flexible electric heating film; 5. Silicone clip. Detailed Implementation

[0020] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0021] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application pertains.

[0022] In industrial sampling, the specifications of sampling bottles are not arbitrarily selected, but are strictly determined based on the type of analysis, safety regulations, and current sampling standards (such as ASTM D4057, GB / T 4756, etc.). For example, for trace component analysis (such as trace sulfur content or moisture determination), smaller volume sampling bottles (such as 100 mL) are usually used to reduce the gas phase space and suppress the fractionation of light and heavy components, thereby ensuring the representativeness of the sample. On the other hand, physical property testing (such as Reid vapor pressure, density, or viscosity determination) often requires larger volumes (such as 500 mL or 1 L) to meet the minimum sample injection requirements of the testing instruments. Because sampling bottles of different volumes must comply with the corresponding industrial standards, their outer diameters also form several fixed specifications, with common bottle diameters ranging from 35 mm to 65 mm, exhibiting a clear multi-specification characteristic.

[0023] This application provides a protective device for heat preservation and anti-condensation of sampling bottles. Under the premise of ensuring the effective heat preservation and anti-condensation performance of sampling bottles in low-temperature environments, a single device of the same specification can reliably accommodate sampling bottles of various diameters.

[0024] like Figures 1 to 6 As shown, this application provides a protective device for heat preservation and anti-condensation of sampling bottles, comprising: The cylinder 1 has openings at both ends, and the bottom end cap 2 is sealed to the first end of the cylinder 1. The cylinder 1 comprises, from the inside out, a heating layer 11, a heat insulation layer 12, and a protective layer 13; The heating layer 11 includes a graphene-modified elastic matrix and a flexible electric heating film 49 embedded in the elastic matrix. The inner surface of the elastic matrix is ​​integrally formed with a plurality of radially inwardly protruding elastic elements 14, which are arranged at intervals along the circumferential direction for radial positioning of the sampling bottle. The heating layer 11 is formed by rolling a sheet, and its two circumferentially mating end faces 111 overlap at an oblique angle to form an elastic gap that can expand in the circumferential direction. The thermal insulation layer 12 is bonded to the outer surface of the elastic substrate by an intermittent adhesive structure 15. The intermittent adhesive structure 15 includes a plurality of adhesive members spaced apart along the circumferential direction. An unbonded area is formed between adjacent adhesive members. The unbonded area is configured to allow relative sliding between the heating layer 11 and the thermal insulation layer 12 in the circumferential direction. The protective layer 13 is bonded to the outer surface of the insulation layer 12.

[0025] Specifically, the cylinder 1 is the main structure of the protective device, which is sealed to the bottom end cap 2 or integrally formed to form a cup sleeve. The cylinder 1 is a hollow tube, and its internal cavity is used to insert the sampling bottle. The second end of the cylinder 1 is used to remove and place the sampling bottle. The inner diameter of the heating layer 11 inside the cylinder 1 can be specifically designed according to actual needs to form various specifications and models.

[0026] In this application, devices of the same specification can be adapted to sampling bottles within a certain diameter range. In some embodiments, to improve adaptability, the protective device includes three models: small, medium, and large, with each model achieving graded elastic adaptation through the elastic element 14 and the elastic gap; wherein: The inner diameter of the heating layer 11 of the small-sized protective device is 35 mm, which is used to adapt to the sampling bottle with an outer diameter of 35~45 mm. The heating layer 11 of the medium-sized protective device has an inner diameter of 45 mm, which is used to fit the sampling bottle with an outer diameter of 45~55 mm. The heating layer 11 of the larger model of the protective device has an inner diameter of 55 mm, which is used to fit the sampling bottle with an outer diameter of 55~65 mm.

[0027] That is, the three specifications and models of protective devices can cover the common bottle outer diameter range.

[0028] The bottom cap 2 is a bottom sealing structure for the protective device. In some embodiments, the bottom cap 2 is a flexible silicone sleeve bottom, and the inner surface of the flexible silicone sleeve bottom is recessed inward to form a curved limiting groove 21. The heating layer 11 is located radially outside the limiting groove 21. The limiting groove 21 is used to provide axial support and radial positioning for the bottom of the sampling bottle.

[0029] In some embodiments, the apparatus further includes: The first sealant layer 22 and the second sealant layer 23 are both in a continuous ring shape; The first sealant layer 22 forms a sealing connection between the inner surface of the flexible silicone sleeve bottom and the end face of the first end of the cylinder 1, and the first sealant layer 22 is located on the outer side of the heating layer 11 in the radial direction. The second sealant layer 23 fills the corner area between the outer peripheral sidewall of the first end of the cylinder 1 and the outer surface of the flexible silicone sleeve bottom, so that the two form a sealed connection.

[0030] Specifically, the flexible silicone sleeve bottom can be made of a 2 mm thick medical-grade circular silicone plate, with a 1 mm deep limiting groove 21 in the center of its inner surface. Projected along the axial direction of the cylinder 1, the limiting groove 21, the heating layer 11, and the first sealing layer 22 are distributed sequentially from the inside to the outside. The limiting groove 21 is used to accommodate the bottom of the sampling bottle, achieving radial positioning, automatic alignment and centering, and ensuring uniform force on the bottle body.

[0031] The first sealing layer 22 is an annular sealing ring with a width of 5 mm, disposed between the inner surface of the bottom end cap 2 and the end face of the first end of the cylinder 1. It can be bonded to the end face of the insulation layer 12 and / or the end face of the protective layer 13 to allow circumferential expansion of the elastic gap of the heating layer 11 while forming a sealed connection.

[0032] During assembly, the silicone sheet can be horizontally pressed into the first end of the cylinder 1, and a laboratory standard weight can be placed on it for 30 minutes to cure. After curing, a second sealant layer 23 (e.g., 704 flame-retardant silicone rubber) is applied to the angle between the outer wall of the protective layer 13 and the outer surface of the bottom end cap 2, and then smoothed to form a rounded chamfer. The first sealant layer 22 seals the bottom end cap 2 and the end face of the cylinder 1, while the second sealant layer 23 fills the corner area. Together, they form a sealed waterproof barrier, improving protection against muddy and muddy environments in the field.

[0033] Optionally, in some embodiments, the device further includes a top flexible end cap. The top flexible end cap may be made of flexible silicone material. The top flexible end cap is detachably and sealingly connected to the second end of the cylinder 1 (e.g., through an elastic closure or Velcro), used to seal the top opening of the cylinder 1 after sampling, thereby reducing heat loss and preventing external contaminants from entering. Furthermore, to avoid the bottle mouth, cap, or external connector of the sampling bottle, the top flexible end cap may have an elastic closure structure (such as a central opening with an elastic edge), a cross-shaped clearance seam, or a foldable cap structure. The heating layer 11 is used to generate heat after being energized and transfer the heat to the sampling bottle wall, so that the bottle wall temperature is stably maintained within a preset range (e.g., 5~15℃), thereby effectively keeping the temperature warm and preventing condensation.

[0034] The elastic matrix can be made of graphene-modified wide-temperature-range hydrogenated nitrile butadiene rubber (HNBR), which has high thermal conductivity (thermal conductivity 1.5~3.0 W / (m·K)) and ≥300% tensile / compression ratio. It does not swell, degrade or chemically react under harsh working conditions such as crude oil splashing or acid gas leakage, ensuring that the internal structure of the heating layer 11 is not corroded or damaged.

[0035] The preparation method of graphene-modified elastic matrix includes: selecting HNBR raw rubber with an acrylonitrile content of 36%~43%, adding nano-graphene micro flakes (mass fraction of 2%~8%) that have been surface modified by KH-550 aminosilane coupling agent, and mixing in an internal mixer at 80~100℃ and 40~60 rpm for 15~20 minutes to obtain the compound rubber.

[0036] Before lamination, the surface of the flexible electric heating film 49 is subjected to ultrasonic degreasing pretreatment using anhydrous ethanol; then, both sides of the flexible electric heating film 49 are evenly wiped with a silicone primer (such as HR-328-1 or ChemLok 205+624) to improve its surface tension.

[0037] The pretreated PI film is placed in a mold, and the above-mentioned compound rubber is injected. It is then subjected to pressure vulcanization at 160~170℃ and 10~15MPa for 10~15 minutes. After demolding, multiple pre-set elastic elements 14 are naturally formed on the inner side of the heating layer 11.

[0038] In some embodiments, a plurality of elastic elements 14 are arranged at equal intervals along the circumferential direction, each elastic element 14 having an arc-shaped raised structure, and the cross-sectional area gradually decreases from its fixed end connected to the elastic matrix to its free end.

[0039] The number of elastic elements 14 can be 3, 4 or even more, the height can be 10-20 mm, and the cross-sectional area gradually decreases from the fixed end connected to the elastic matrix to the free end (i.e., thick at the root and thin at the top).

[0040] When a small-diameter sampling bottle (e.g., 35 mm outer diameter) is placed, the elastic element 14 acts as a flexible support point, gripping the bottle from all sides and forcibly centering it (the elastic element 14 is moderately compressed), effectively preventing the bottle from shaking, slipping, or sticking to one side during transport. When a large-diameter sampling bottle (e.g., 65 mm outer diameter) is placed, the elastic element 14 is completely flattened and flush with the inner surface of the heating layer 11, achieving non-destructive compression and avoidance by "locking when encountering small and flattening when encountering large," without occupying radial space. At the same time, the elastic element 14 itself acts as a high thermal conductivity path, directly conducting heat to the bottle wall; the tiny annular air layer (thickness < 10 mm) formed by its support greatly suppresses natural convection under sealed conditions and small temperature differences (e.g., 5~15℃), forming a stable constant-temperature air bath layer, avoiding local hot spots, and allowing heat to gently and evenly envelop the sample, thereby ensuring that light hydrocarbon components do not volatilize due to local overheating.

[0041] The flexible electric heating film 49 is used to generate heat when energized to provide heat to the sampling bottle; it can be selected from one of polyimide (PI) heating film, silicone heating film or polyester heating film.

[0042] In some embodiments, the flexible electric heating film 49 has serpentine, equidistantly spaced metal heating traces inside; the line width, line spacing, and number of loops of the metal heating traces are configured such that the equivalent resistance of the flexible electric heating film 49 is 2.5Ω to 8.0Ω; the flexible electric heating film 49 is used to connect to a 5V DC power supply 41.

[0043] Specifically, the flexible electric heating film 49 has serpentine, equidistantly spaced metal heating traces (coverage can be >85%) formed inside through an etching process. By adjusting the line width, spacing, and number of loops of the metal heating traces, the equivalent resistance of the flexible electric heating film 49 is made to be 2.5Ω~8.0Ω, preferably 3.0Ω~5.0Ω. The rated operating voltage of the flexible electric heating film 49 is 5V DC, used to connect to a 5V DC power supply 41 (such as a portable power bank). At this voltage, the heating power is 3W~10W, corresponding to a heating surface power density of 125W / m². 2 ~400W / m 2 This power density can cover the steady-state heat loss under extremely cold conditions of -20℃ and provide a certain thermal redundancy, thereby ensuring sufficient thermal redundancy to maintain the constant temperature heating requirement of 5~15℃.

[0044] like Figure 1 and Figure 6 As shown, in some embodiments, it also includes: Negative temperature coefficient thermistor 45, wired control box 4, and over-temperature protection switch 48; The negative temperature coefficient thermistor 45 is connected to the elastic substrate and is configured to collect the temperature signal of the heating layer 11 or the sampling bottle. The wired control box 4 integrates a reverse connection protection element 42, a DC-DC boost converter 43, a digital temperature control module 44, and a switching device 46 controlled by the digital temperature control module 44. The first end of the reverse connection protection element 42 is used to connect to the positive terminal of the DC power supply 41, the second end of the reverse connection protection element 42 is electrically connected to the power input terminal of the DC boost converter 43 and the first end of the switching device 46, and the boost output terminal of the DC boost converter 43 is electrically connected to the power supply terminal of the digital temperature control module 44. The digital temperature control module 44 is signal-connected to the negative temperature coefficient thermistor 45, and the control signal output terminal of the digital temperature control module 44 is electrically connected to the control terminal of the switching device 46. The digital temperature control module 44 is configured to control the switching device 46 to turn on and off according to the temperature signal collected by the negative temperature coefficient thermistor 45, so that the flexible electric heating film 49 can perform closed-loop constant temperature control to maintain the constant temperature heating requirement of 5~15℃. The second end of the switching device 46 is electrically connected to the flexible electric heating film 49 through the over-temperature protection switch 48, and the over-temperature protection switch 48 is in thermal contact with the flexible electric heating film 49; the over-temperature protection switch 48 is configured to disconnect the power supply circuit of the flexible electric heating film 49 when the temperature of the flexible electric heating film 49 exceeds its preset action threshold.

[0045] In some embodiments, the wired control box 4 is a waterproof junction box constructed through the coordinated use of materials and sealing structure, and its power input terminal and output terminal are respectively provided with waterproof cable connectors; The terminals of the flexible electric heating film 49, the leads of the negative temperature coefficient thermistor 45, and the lead holes of the tube 1 are all sealed with flame-retardant silicone rubber potting. The circumferential edges of the elastic matrix are sealed with silicone rubber to form a waterproof seal.

[0046] Specifically, the negative temperature coefficient thermistor 45 is a resistor that is standardly matched with the digital temperature control module 44 (e.g., W1209).

[0047] To separate the heat-generating actuator from the control and calculation end, reduce the risk of electrical sparks and overheating under abnormal operating conditions, and improve the safety of the low-voltage electrical control system in the field, the device is equipped with an independent external wired control box 4. The wired control box 4 is made of acrylonitrile-butadiene-styrene copolymer (ABS) material and has an IP67-level protection structure. Its dimensions are 75mm × 55mm × 30mm. The front of the box has a window and a sealed transparent acrylic plate to display the temperature collected by the negative temperature coefficient thermistor 45. Waterproof cable connectors are installed at both ends. A power cord with a USB-C plug runs through the waterproof cable connector at the upper end of the wired control box 4. This USB-C plug is used to connect to an external DC power supply 41. The power cord can be 1-2 meters long for easy placement close to the body. A four-core composite flexible wire runs through the waterproof cable connector at the lower end, used to connect the flexible electric heating film 49 and the negative temperature coefficient thermistor 45 inside the insulation sleeve 1. When working in extremely cold environments, operators can place the control box 4 along with the power supply (such as a power bank) close to their body to maintain battery activity using body heat, ensuring reliable power supply and battery life under low-temperature conditions.

[0048] An over-temperature protection switch 48 (normally closed type, operating temperature 30℃~45℃) is connected in series in the power supply circuit of the flexible electric heating film 49. The over-temperature protection switch 48 can be directly attached to the outer surface of the flexible electric heating film 49 (e.g., by using thermally conductive adhesive or mechanical pressing) to make thermal contact with it. It is used to cut off the heating circuit when the digital temperature control module 44 fails or there is a local abnormal temperature rise, so as to prevent the light hydrocarbon components from volatilizing due to overheating.

[0049] Furthermore, a thermal fuse (temperature fuse) can be connected in series in the power supply circuit of the flexible electric heating film 49, with its operating temperature set to 60℃~70℃, to provide ultimate protection against dry burning; or, an over-temperature protection switch 48 can be connected in series in the power supply circuit of the flexible electric heating film 49, with its operating temperature set to 60℃~70℃, as a double hardware protection.

[0050] The reverse connection protection element 42 is used to prevent reverse connection of the power supply to avoid damage to subsequent circuits due to reverse voltage. In a 5V low-voltage power supply system, to reduce the impact of the on-state voltage drop on the actual power of the flexible electric heating film 49 and the power supply stability of the digital temperature control module 44, the reverse connection protection element 42 can be a Schottky diode, a P-channel metal-oxide-semiconductor field-effect transistor (PMOS) ideal diode reverse connection protection circuit, or a low-voltage-drop reverse connection protection module. When a Schottky diode is selected, the Schottky diode is connected in series with the positive input terminal of the DC power supply 41, its anode is connected to the positive terminal of the DC power supply 41, and its cathode is electrically connected to the power input terminal of the DC boost converter 43 and the first terminal of the switching device 46, respectively.

[0051] The DC-DC boost converter 43 boosts the 5V DC power supply 41 to 12V. Its boost output is electrically connected to the power supply terminal of the digital temperature control module 44 to power the module. This 12V voltage does not enter the power supply circuit of the flexible electric heating film 49. The digital temperature control module 44 is connected to the negative temperature coefficient thermistor 45 and controls the switching of the relay based on the acquired temperature signal. The flexible electric heating film 49 is driven by the 5V power supply through the switching device 46, thereby preventing the 12V voltage from accidentally entering the heating film load.

[0052] The digital temperature control module 44 (e.g., W1209) is configured in heating mode, with a temperature control hysteresis set to 2.0℃ and a target temperature set to 10℃ (i.e., the relay closes for heating at 8℃ and disconnects at 10℃), and an over-temperature alarm threshold of 25℃ is set. Combined with the over-temperature protection switch 48, this forms dual over-temperature protection. This closed-loop control can effectively control the sampling bottle wall temperature between 8 and 10℃ (temperature difference ±2℃), meeting the constant temperature requirement of 5 to 15℃.

[0053] The switching device 46 is used to connect or disconnect the power supply circuit of the flexible electric heating film 49 under the control of the digital temperature control module 44. The switching device 46 can be any one of a mechanical relay, a solid-state relay (SSR), or a metal-oxide-semiconductor field-effect transistor (MOSFET).

[0054] In some embodiments, the switching device 46 can be a mechanical relay on the W1209 digital temperature control module 44. In this case, the input terminal (COM) of the switching device 46 is electrically connected to the cathode of the Schottky diode, the output terminal (NO) of the switching device 46 is electrically connected to the fuse, and the control terminal (COIL) of the switching device 46 is connected to the control signal output terminal (CTRL) of the digital temperature control module 44. _ OUT) Electrical connection. The sensor input terminal (IN) of the digital temperature control module 44 is connected to the negative temperature coefficient thermistor 45 for signal transmission.

[0055] In other embodiments, since the SSR and MOSFET switching devices 46 are contactless electronic switches, they have advantages such as fast response, no sparks, and long lifespan, making them more suitable for flammable and explosive outdoor environments such as those involving oil and gas. This application preferably uses SSR or MOSFET switching devices 46; for example, the switching device 46 uses an SSR that is directly matched to a 5V logic level.

[0056] In some embodiments, the wired control box 4 also integrates an energy limiting protection module 47, which includes a fuse, a positive temperature coefficient self-resetting current limiting thermistor, and an overvoltage clamping device. The second terminal of the switching device 46 is connected in series with the fuse, the positive temperature coefficient self-resetting current-limiting thermistor and the over-temperature protection switch 48. The first end of the overvoltage clamping device is electrically connected to the connection node between the fuse and the positive temperature coefficient self-recovering current-limiting thermistor, and its second end is electrically connected to the negative terminal of the DC power supply 41.

[0057] Specifically, the rated fusing current of the fuse can be 3A; the nominal holding current of the positive temperature coefficient self-recovering current-limiting (PTC) thermistor can be 2.0A, and the trigger current can be 3.0A. The overvoltage clamp can use two Zener diodes connected in parallel, each with a voltage regulation value of 5.6V and a power rating of 5W (i.e., 5.6V / 5W). The parallel connection increases the clamping power, shares the current load, and reduces the risk of uneven current distribution through matching selection or current sharing design. Alternatively, the overvoltage clamp can also use a transient voltage suppressor diode (TVS diode) or a combination of a Zener diode and a TVS diode. This application preferably uses two Zener diodes connected in parallel.

[0058] In this energy limiting protection module 47, a Zener diode clamps the voltage below 5.6V to prevent abnormal voltage increases from causing a sudden surge in power; a PTC thermistor's resistance increases sharply when the current exceeds 3.0A, limiting the current; and a fuse blows in the event of an extreme short circuit, completely cutting off the circuit. Under normal operating conditions (5V / 2.5Ω, maximum power 10W), even with continuous heating, the device's equilibrium temperature remains well below 135℃. This structure limits voltage, current, and heat release under abnormal operating conditions, reducing the risk of electrical sparks and overheating. The specific explosion-proof rating of this module is subject to the overall machine testing and certification results.

[0059] With the above configuration, the device can be powered by a regular power bank. Under simulated environment of -20℃ and intermittent temperature control conditions, it can achieve continuous heat preservation for several hours when paired with a 10000 mAh power bank (the specific battery life varies depending on factors such as ambient temperature, sampling bottle size, set temperature, thickness of insulation layer 12, and heating duty cycle).

[0060] In terms of safety protection, there are no exposed electrical contacts inside the cylinder 1. The wiring terminals of the flexible electric heating film 49 are wrapped with halogen-free heat shrink tubing and deeply injected with 704 flame-retardant silicone rubber for complete sealing; the digital temperature control module 44 is completely sealed in an independent external wire control box 4. At the same time, the external interface uses an IP67-rated USB waterproof connector and is wrapped with waterproof tape; the edges of the heating layer 11, the gaps at the bottom of the sleeve, and the wire leads are all sealed with 704 silicone rubber for secondary sealing, forming a fully enclosed, insulated, and waterproof barrier, effectively preventing leakage and explosion hazards caused by moisture infiltration.

[0061] For complex well site environments involving mud, oil, and rain / snow, this device employs a multi-layered, cold-bonded, fully enclosed waterproof process, with external interfaces meeting IP67 protection standards. Combined with a 5V DC low-voltage power supply and an energy limiting protection module 47, it significantly reduces the risk of electrical spark leakage and overheating under abnormal operating conditions, thus outperforming traditional 220V heating equipment in flammable and explosive areas in terms of leakage and fire / explosion risks. The specific explosion-proof rating of the protection device described in this application is subject to the overall machine testing and certification results. This low-voltage, fully potted, multi-sealed design effectively suppresses the possibility of explosions caused by electrical sparks.

[0062] like Figure 6 As shown, in a preferred embodiment of this application, the electrical control system of the protection device includes the following four circuits: Heating main circuit: The positive terminal of the 5V DC power supply 41 is connected to the first terminal of the switching device 46 after passing through the reverse connection protection component 42. The second terminal of the switching device 46 is connected to the positive terminal of the flexible electric heating film 49 after being connected in series with the energy limiting protection module 47 and the over-temperature protection switch 48. The negative terminal of the flexible electric heating film 49 is connected back to the negative terminal of the 5V DC power supply 41.

[0063] Control power supply circuit: The positive terminal of the 5V DC power supply 41 is connected to the DC boost converter 43 after passing through the reverse connection protection component 42. After being boosted to 12V, it supplies power to the digital temperature control module 44.

[0064] Temperature acquisition circuit: The negative temperature coefficient thermistor 45 is electrically connected to the signal input terminal of the digital temperature control module 44, and is used to transmit the acquired temperature signal to the digital temperature control module 44.

[0065] Control loop: The control signal output terminal of the digital temperature control module 44 is electrically connected to the control terminal of the switching device 46. The digital temperature control module 44 sends a control signal to control the switching device 46 to turn on and off based on the temperature signal collected by the negative temperature coefficient thermistor 45.

[0066] The two mating end faces 111 of the heating layer 11 extend along the axial direction of the cylinder 1 and are cut into an oblique profile, forming an elastic gap that can expand circumferentially. An elastic sealant (such as K-588) with a thickness of about 1 mm can be applied to the oblique surface for overlapping and curing to increase the bonding area and improve tensile strength. This oblique overlapping seam is the radial elastic expansion seam: when a large-diameter sampling bottle is inserted, the oblique seam slides open, providing circumferential expansion allowance for the inelastic outer layer.

[0067] To prevent external moisture from entering, in some embodiments the two mating end faces 111 of the heating layer 11 are overlapped at a 45° angle; The device also includes an elastic sealing strip 3, which is attached to the outer surface of the protective layer 13; the elastic sealing strip 3 extends axially and is aligned with the elastic gap in the circumferential direction to cover the opening area of ​​the elastic gap and prevent external moisture from entering.

[0068] like Figure 1 and Figure 3 As shown, in some embodiments, the two mating end faces 111 of the heating layer 11 overlap at a 45° angle. The device also includes an elastic sealing strip 3, which is attached to the outer surface of the protective layer 13; the elastic sealing strip 3 extends axially and is aligned with the elastic gap in the circumferential direction to cover the opening area of ​​the elastic gap and prevent external moisture from entering.

[0069] Specifically, the elastic sealing strip 3 (such as a 2mm thick butyl rubber waterproof strip) is attached to the outer surface of the protective layer 13. The elastic sealing strip 3 extends axially and is aligned with the elastic gap in the circumferential direction, completely covering the gap opening area.

[0070] The heating layer 11 and the insulation layer 12 are bonded together by applying adhesive in dots or strips with a circumferential spacing of 2-3 cm (not full bonding), forming an interlayer sliding structure with an inner pull and an outer follow. When the heating layer 11 is compressed and expands, the insulation layer 12 can slide relative to the unbonded area and release the circumferential space through the overlapping surface of the 45° oblique seam, thereby preventing the insulation material from being stretched and broken.

[0071] The device combines a 45° angled elastic expansion joint with a non-full-volume bonding process, and the elongation of the elastic matrix material is not less than 300%. The device is available in three graded sizes: small, medium, and large. It utilizes the elastic gap and discontinuous bonding structure 15 to release the circumferential deformation allowance, thereby adapting to sampling bottles of corresponding diameter ranges, reducing equipment redundancy in field operations, and lowering procurement costs.

[0072] The insulation layer 12 is used to block external cold energy from being conducted to the heating layer 11 and the sampling bottle, and to maintain a constant temperature of the bottle wall and prevent condensation. In some embodiments, the insulation layer 12 is a hydrophobic silica aerogel composite felt with a water contact angle greater than 140° and a thermal conductivity less than 0.020 W / (m·K). Specifically, the insulation layer 12 can be made of a hydrophobic silica aerogel composite felt with a thickness of 8 mm, having a water contact angle greater than 140°, such as 150° or larger, and a thermal conductivity of less than 0.020 W / (m·K) at room temperature. Under low-temperature conditions, the aerogel composite felt can still maintain a low thermal conductivity, effectively reducing the impact of external low temperatures on the internal temperature field of the cylinder 1, thereby suppressing the risk of condensation on the outer wall of the sampling bottle. At the same time, combined with active heating and closed-loop temperature control, the bottle wall temperature can be kept stably higher than the dew point temperature of the residual moisture inside the bottle, thereby preventing condensation on the inner wall and volatilization of light hydrocarbons, and ensuring the preservation of the sample phase.

[0073] The heating layer 11 and the hydrophobic silica aerogel insulation cotton can be dotted with Kraft K-588 silicone sealant to avoid the adhesive layer being too thick and affecting the uniformity of heat conduction and to allow interlayer slippage.

[0074] The protective layer 13 is attached to the outer surface of the insulation layer 12 to resist outdoor mechanical friction, rain and snow, and oil splashes, and to help isolate external moisture. In some embodiments, the protective layer 13 is a hydrophobic flexible material selected from any one of neoprene foam, polyurethane film, polyurethane composite fabric, or silicone rubber composite fabric.

[0075] Specifically, the protective layer 13 is made of a hydrophobic flexible material, which can be selected from any one of neoprene foam (diving material), polyurethane (TPU) film, polyurethane composite fabric, or silicone rubber composite fabric. Among them, the neoprene foam contains micro-bubbles, which can act as a second thermal insulation barrier. It remains soft even at -20℃ and is inexpensive. The TPU composite fabric has high water resistance, high abrasion resistance, and moderate elasticity, making it suitable for the complex friction environment at the wellhead. The silicone rubber composite fabric has a wide temperature range (-60℃ to 200℃), a smooth surface, and natural hydrophobic and oleophobic properties, making it easy to wipe clean and self-cleaning.

[0076] The insulation layer 12 and the protective layer 13 can be bonded together using Loctite 587 adhesive and secured in sections using cable ties. The surface of the protective layer 13 has a dense, non-polar structure, possessing natural oleophobic and hydrophobic properties (lotus leaf effect) against crude oil and drilling mud. Highly corrosive oil sludge splashes cannot penetrate into the internal insulation layer 12, and it can be self-cleaned with simple wiping, allowing the device to maintain structural integrity and long-term thermal insulation performance even in extremely cold, muddy, and oily environments.

[0077] In some embodiments, after stripping 3-5 mm of wire from all electrical terminals, the terminals are tightened to prevent loose connections. The lead-out wires are arranged along the "Z"-shaped wiring grooves reserved on the outer surface of the cylinder 1. Butyl rubber waterproof strips are compacted in the grooves, and the wires are pressed on the outside with silicone clips 5 (fixed to the protective layer 13) at intervals of 30-40 mm to form an anti-pull structure, eliminating the safety hazards of leakage and explosion caused by the dragging of wires during field operations.

[0078] Compared to existing technologies, the protective device for heat preservation and anti-condensation of sampling bottles provided in this application utilizes multiple elastic elements 14 for radial positioning of the sampling bottle. When a sampling bottle with a relatively small outer diameter (e.g., 35mm) is inserted, the multiple elastic elements 14 are moderately compressed, collectively supporting the bottle body from all sides to center it, effectively preventing the bottle body from colliding with the hard inner wall during transportation and breaking or leaking. When a sampling bottle with a relatively large outer diameter (e.g., 45mm) is inserted, the elastic elements 14 are compressed to be flush with the inner surface of the elastic matrix, while the beveled overlap gap of the heating layer 11 passively opens, increasing the adaptability of the inner diameter of the heating layer 11. During this process, the unbonded area between the heating layer 11 and the insulation layer 12 allows for circumferential relative sliding between the two, effectively releasing deformation stress and preventing the insulation layer 12 from thinning, cracking, or detaching due to stretching, thereby ensuring its structural integrity and long-term thermal insulation performance. Thus, a single device can safely adapt to various sizes of sampling bottles, significantly improving the portability and equipment versatility for field operations.

[0079] The flexible electric heating film 49 embedded in the heating layer 11 generates heat when energized. The heat is rapidly transferred to the sampling bottle wall via the graphene-modified, highly thermally conductive elastic matrix and its integrally molded elastic element 14, maintaining the bottle wall temperature stably within a preset range (e.g., 5-15℃). This ensures the bottle wall temperature remains consistently above the dew point temperature of typical outdoor air, effectively suppressing condensation. The insulation layer 12 uses a low thermal conductivity material, effectively blocking heat intrusion from the external low-temperature environment, significantly reducing heating power consumption, and ensuring temperature control stability. The outer protective layer 13 resists external mechanical damage and environmental corrosion, ensuring that the internal heating layer 11 and insulation layer 12 are not affected by external interference. This enables the long-term effective operation of the thermal management system, preventing insulation failure and temperature instability due to shell damage, thus avoiding the risk of condensation.

[0080] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A protective device for heat preservation and anti-condensation of sampling bottles, characterized in that, include: The cylinder has openings at both ends, and the bottom end cap is sealed to the first end of the cylinder. The cylinder comprises, from the inside out, a heating layer, a heat insulation layer, and a protective layer; The heating layer includes a graphene-modified elastic matrix and a flexible electric heating film embedded in the elastic matrix. The inner surface of the elastic matrix is ​​integrally formed with multiple elastic elements that protrude radially inward. The multiple elastic elements are arranged at intervals along the circumferential direction for radial positioning of the sampling bottle. The heating layer is formed by rolling a sheet, with its two circumferentially connected end faces at an oblique angle to form an elastic gap that can expand circumferentially. The thermal insulation layer is bonded to the outer surface of the elastic substrate by an intermittent adhesive structure, the intermittent adhesive structure comprising a plurality of adhesive members spaced apart along the circumferential direction, and an unbonded area formed between adjacent adhesive members, the unbonded area being configured to allow relative sliding between the heating layer and the thermal insulation layer in the circumferential direction; The protective layer is bonded to the outer surface of the insulation layer.

2. The protective device for heat preservation and anti-condensation of sampling bottles according to claim 1, characterized in that, Multiple elastic elements are arranged at equal intervals along the circumferential direction. Each elastic element has an arc-shaped raised structure, and its cross-sectional area gradually decreases from the fixed end connected to the elastic matrix to the free end.

3. The protective device for heat preservation and anti-condensation of sampling bottles according to claim 1, characterized in that, The two mating end faces of the heating layer overlap at a 45° angle. The device also includes an elastic sealing strip that fits onto the outer surface of the protective layer; the elastic sealing strip extends axially and is aligned with the elastic gap in the circumferential direction to cover the opening area of ​​the elastic gap and prevent external moisture from entering.

4. The protective device for heat preservation and anti-condensation of sampling bottles according to claim 1, characterized in that, The insulation layer is a hydrophobic silica aerogel composite felt with a water contact angle greater than 140° and a thermal conductivity less than 0.020 W / (m·K). The protective layer is a hydrophobic flexible material selected from any one of neoprene foam, polyurethane film, polyurethane composite fabric, or silicone rubber composite fabric.

5. A protective device for heat preservation and anti-condensation of sampling bottles according to claim 1, characterized in that, The bottom cap is a flexible silicone sleeve bottom. The inner surface of the flexible silicone sleeve bottom is recessed inward to form a curved limiting groove. The heating layer is located on the outside of the limiting groove in the radial direction. The limiting groove is used to provide axial support and radial positioning for the bottom of the sampling bottle. The device also includes a first sealant layer and a second sealant layer, both of which are in a continuous ring shape; The first sealant layer forms a sealing connection between the inner surface of the flexible silicone sleeve bottom and the end face of the first end of the cylinder, and the first sealant layer is located on the outer side of the heating layer in the radial direction; The second sealant layer fills the corner area between the outer peripheral sidewall of the first end of the cylinder and the outer surface of the flexible silicone sleeve bottom, so that the two form a sealed connection.

6. A protective device for heat preservation and anti-condensation of sampling bottles according to claim 1, characterized in that, The flexible electric heating film has serpentine, equidistantly spaced metal heating traces inside; the line width, line spacing, and number of loops of the metal heating traces are configured such that the equivalent resistance of the flexible electric heating film is 2.5Ω to 8.0Ω; the flexible electric heating film is used to connect to a 5V DC power supply.

7. A protective device for heat preservation and anti-condensation of sampling bottles according to claim 6, characterized in that, Also includes: Negative temperature coefficient thermistors, wired control boxes, and over-temperature protection switches; The negative temperature coefficient thermistor is connected to the elastic matrix and configured to collect the temperature signal of the heating layer or the sampling bottle; The wired control box integrates a reverse connection protection component, a DC-DC boost converter, a digital temperature control module, and a switching device controlled by the digital temperature control module. The first end of the reverse connection protection element is used to connect to the positive terminal of the DC power supply, the second end of the reverse connection protection element is electrically connected to the power input terminal of the DC boost converter and the first end of the switching device, and the boost output terminal of the DC boost converter is electrically connected to the power supply terminal of the digital temperature control module. The digital temperature control module is connected to the negative temperature coefficient thermistor signal, and the control signal output terminal of the digital temperature control module is electrically connected to the control terminal of the switching device. The digital temperature control module is configured to control the switching device to switch on and off according to the temperature signal collected by the negative temperature coefficient thermistor, so as to enable closed-loop constant temperature control of the flexible electric heating film. The second terminal of the switching device is electrically connected to the flexible electric heating film through the over-temperature protection switch, and the over-temperature protection switch is in thermal contact with the flexible electric heating film. The over-temperature protection switch is configured to disconnect the power supply circuit of the flexible electric heating film when the temperature of the flexible electric heating film exceeds its preset action threshold.

8. A protective device for heat preservation and anti-condensation of sampling bottles according to claim 7, characterized in that, The wired control box also integrates an energy limiting protection module, which includes a fuse, a positive temperature coefficient self-resetting current limiting thermistor, and an overvoltage clamping device. The second terminal of the switching device is connected in series with the fuse, the positive temperature coefficient self-resetting current-limiting thermistor and the over-temperature protection switch. The first end of the overvoltage clamping device is electrically connected to the connection node between the fuse and the positive temperature coefficient self-recovering current-limiting thermistor, and its second end is electrically connected to the negative terminal of the DC power supply.

9. A protective device for heat preservation and anti-condensation of sampling bottles according to claim 7, characterized in that, The wired control box is a waterproof junction box constructed through the synergy of material and sealing structure, and its power input and output ends are respectively equipped with waterproof cable connectors; The terminals of the flexible electric heating film, the leads of the negative temperature coefficient thermistor, and the lead holes of the cylinder are all sealed with flame-retardant silicone rubber potting. The circumferential edges of the elastic matrix are sealed with silicone rubber to form a waterproof seal.

10. A protective device for heat preservation and anti-condensation of sampling bottles according to claim 1, characterized in that, The protective device includes three models: small, medium, and large. The inner diameter of the heating layer of the small-sized protective device is 35 mm, which is used to adapt to the sampling bottle with an outer diameter of 35~45 mm. The inner diameter of the heating layer of the medium-sized protective device is 45 mm, which is used to fit the sampling bottle with an outer diameter of 45~55 mm. The inner diameter of the heating layer of the larger model of the protective device is 55 mm, which is used to fit the sampling bottle with an outer diameter of 55~65 mm.

Images