Gas pipeline valve section heat preservation anti-frost coating protection assembly

Abstract

The application discloses a gas pipeline valve segmented heat preservation anti-frosting coating protection component. The component comprises, from outside to inside, an aluminum foil protective outer skin, a heat preservation layer and a flexible anti-freezing inner lining which are sequentially sleeved outside a gas pipeline and a valve, and a split valve heat preservation cover which is sleeved outside the valve; the aluminum foil protective outer skin is a cylindrical aluminum foil shell which is arranged in segments along the pipeline axial direction, and adjacent segments are fixed by stainless steel straps; the heat preservation layer is a cylinder-shaped aero gel felt or polyurethane foam sleeve which is sleeved outside the flexible anti-freezing inner lining; and the flexible anti-freezing inner lining is a thin sleeve of silicone rubber or EPDM rubber which is tightly attached to the outer wall of the pipeline. The component has a combined structure of "segmented coating + valve independent heat preservation cover + anti-freezing inner lining water absorption", effectively blocks the heat exchange between low-temperature gas and the outside world, prevents the pipeline outer wall and the valve from frosting and freezing, is convenient for segmented disassembly, maintenance and valve operation, and is suitable for the gas pipeline system of LNG, liquid nitrogen, liquid oxygen and other low-temperature liquid storage tanks.

Description

Technical Field

[0001] This invention relates to the field of thermal insulation and protection technology for cryogenic gas transmission pipelines, and in particular to a segmented thermal insulation and anti-frost coating protection component for gas pipeline valves. Background Technology

[0002] In the storage and transportation systems of cryogenic liquids such as LNG (liquefied natural gas), liquid nitrogen, and liquid oxygen, cryogenic liquid storage tanks are connected to the gas-consuming end or compressor end via gas phase balance pipelines and BOG (boil-off gas) return pipelines. Because the cryogenic gas (temperatures can be as low as -160°C) generated by the evaporation of cryogenic liquids is transported within pipelines, the extremely low temperature of the pipeline outer wall can easily lead to the following problems: Severe frost and freezing: When low-temperature gas flows through pipelines and valves, the pipe wall temperature is much lower than the ambient dew point. Water vapor in the air frosts and freezes on the outer wall of the pipe, especially at the valve stem and flange connection, which makes valve operation difficult or even jammed, affecting emergency shut-off and normal regulation. Large loss of cold energy: The exposed low-temperature pipes exchange heat directly with the outside air, resulting in a large loss of cold energy, which accelerates the evaporation of low-temperature liquid in the storage tank, increases BOG production and processing energy consumption. Personnel safety risks: The surface temperature of frosted pipes is extremely low, and inspection personnel may suffer frostbite if they accidentally touch them; at the same time, there are safety hazards from frost shedding and falling ice. Existing insulation methods have drawbacks: Traditional pipe insulation often involves uniformly covering the entire straight pipe section with rock wool or polyurethane foam. However, when encountering irregular parts such as valves, flanges, and elbows, it is difficult to cover them and the fit is poor. In addition, valves need to be operated frequently, and the integral covering is not easy to disassemble. Maintenance requires damage to the insulation layer, and repeated disassembly and reassembly are costly. Condensation buildup: Ambient air condenses and frosts on the surface of the cold pipe wall. The condensate produced after the frost melts flows along the pipe wall and accumulates at the bottom of the valve or in the insulation layer, accelerating the aging of the insulation material and the corrosion of the metal pipe.

[0003] Therefore, there is an urgent need for a pipe valve protection component that can be segmented, has independent and detachable insulation for valves, effectively prevents frost and freezing, and drains condensate. Summary of the Invention

[0004] To at least partially solve the above problems, a segmented insulation and anti-frost protection component for gas pipeline valves is provided.

[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a segmented insulation and anti-frost protection component for gas pipeline valves, comprising: The aluminum foil protective outer skin is a cylindrical aluminum foil shell that is segmented along the axial direction of the pipe, and is formed by two semi-cylindrical aluminum foil sheets being joined and tightened together. The thermal insulation layer is a cylindrical sleeve made of aerogel felt or polyurethane foam, which is fitted over the outside of the flexible antifreeze lining and has a thickness of 15-30 mm. The flexible antifreeze liner is a thin sleeve made of silicone rubber or EPDM rubber, which tightly covers the outer wall of the pipe and has a microporous water-absorbing layer on the inner surface. The split valve insulation cover is made of two clamshell-shaped aluminum alloy shells joined together. The inner wall of the shell is lined with insulation cotton and is locked to the outside of the valve by quick-release buckles. Stainless steel cable ties, spaced along the axial direction of the pipe, are used to bind and fix the aluminum foil protective outer skin, thermal insulation layer and flexible antifreeze lining to the outside of the pipe; The condensate drainage channel is installed along the axial direction of the pipe at the bottom of the pipe, located between the aluminum foil protective skin and the pipe.

[0006] As a preferred embodiment of the present invention, the outer surface of the aluminum foil protective sheath is provided with a reflective coating, and the thickness of the aluminum foil sheet is 0.3 to 0.8 mm.

[0007] As a preferred embodiment of the present invention, the two halves of the split valve insulation cover are connected by a hinge on one side and locked by a quick-release buckle on the other side; a through hole is provided on the top of the cover for the valve stem to pass through, and a flexible sealing ring is provided at the through hole.

[0008] As a preferred embodiment of the present invention, the axial length of each covered segment is 300-800mm, the butt joints between adjacent segments are staggered, and each segment is provided with at least two stainless steel cable ties.

[0009] As a preferred embodiment of the present invention, the condensate diversion channel is a semi-circular or V-shaped aluminum alloy channel, which is continuously arranged along the bottom of the pipe and extends to the drain outlet at the lowest point of the pipe at both ends.

[0010] As a preferred embodiment of the present invention, the thermal insulation layer is a nano-aerogel felt with a thermal conductivity of no more than 0.020 W / (m·K).

[0011] As a preferred embodiment of the present invention, the thickness of the flexible antifreeze liner is 2-5 mm, and the microporous absorbent layer is a polyurethane open-cell foam layer with a thickness of 1-2 mm.

[0012] As a preferred embodiment of the present invention, the components are arranged in segments along the length of the pipeline and disconnected at the valve, flange and instrument interface positions, with the disconnected positions covered by a split valve insulation cover.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: Segmented wrapping design: Independent wrapping units are set up in segments along the pipeline axis. Each segment can be disassembled and installed separately. It can flexibly avoid flanges, welds, instrument interfaces and other parts. It has strong installation adaptability and facilitates local maintenance and replacement in the later stage without the need for overall removal. Independent insulation cover for valves: The split clamshell structure is locked with quick-release buckles. When the valve needs to be operated or repaired, the cover can be opened simply by loosening the buckles without damaging the insulation layer. It has a high reusability and solves the pain point of "difficult valve maintenance" in traditional whole-coverage valves. Three-layer composite insulation structure: aluminum foil protective outer skin reflects radiant heat + aerogel insulation layer blocks heat conduction + antifreeze lining prevents condensation on the outer wall of the pipe. It has excellent comprehensive insulation performance, and the temperature of the outer wall of the pipe can be increased by more than 30°C compared with the bare pipe, effectively inhibiting frost formation. Antifreeze lining with water absorption and drainage: The microporous water-absorbing layer of the lining absorbs condensate and discharges it through the bottom drainage channel, avoiding the accumulation of condensate in the insulation layer, which would lead to a decrease in insulation performance and pipe corrosion; Easy installation: The components are prefabricated and segmented structures. On-site installation can be completed simply by inserting the pipe, aligning the cover, binding with cable ties, and locking with buckles. It can be operated by a single person and has high construction efficiency. Wide range of applications: Applicable to various cryogenic gas pipeline systems such as gas phase pipelines, BOG return gas pipelines, and tank pressurization pipelines for cryogenic liquid storage tanks such as LNG, liquid nitrogen, liquid oxygen, and liquid argon. Attached Figure Description

[0014] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is an exploded view of the overall structure of the present invention; In the diagram: 1. Aluminum foil protective outer skin; 2. Thermal insulation layer; 3. Flexible antifreeze inner lining; 4. Pipe; 5. Valve; 6. Split-type valve insulation cover; 7. Quick-release buckle; 8. Stainless steel cable tie; 9. Condensate drainage channel. Detailed Implementation

[0015] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0016] Furthermore, if a detailed description of known technologies is unnecessary for illustrating the features of the present invention, it will be omitted.

[0017] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the 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 this invention.

[0018] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0019] Example 1

[0020] like Figure 1 As shown, the present invention provides a segmented insulation and anti-frost coating protective component for gas pipeline valves, comprising: The aluminum foil protective outer skin is a cylindrical aluminum foil shell that is segmented along the pipe axis. Each segment is formed by two semi-cylindrical aluminum foil sheets that are joined and tightened together. The butt joints between adjacent segments are staggered. The outer surface of the aluminum foil protective outer skin is coated with a reflective coating to reduce heat absorption from solar radiation. The thermal insulation layer is a cylindrical sleeve made of aerogel felt or polyurethane foam, which is fitted over the outside of the flexible antifreeze lining. The thickness of the thermal insulation layer is 15-30mm. The flexible antifreeze liner is a thin sleeve made of silicone rubber or EPDM rubber, with an inner diameter that matches the outer diameter of the pipe and tightly wraps around the outer wall of the pipe; the inner surface of the flexible antifreeze liner is provided with a microporous water-absorbing layer to absorb condensation generated by condensation on the outer wall of the pipe. The split valve insulation cover is made of two clamshell-shaped aluminum alloy shells joined together, with insulation cotton attached to the inner wall of the shell; one side of the two shells is connected by a hinge, and the other side is locked by a quick-release buckle; the split valve insulation cover is fitted on the outside of the valve, and a through hole is opened at the top of the shell for the valve stem to pass through. Stainless steel cable ties are installed at intervals along the pipe axis to secure the aluminum foil protective outer layer, thermal insulation layer, and flexible antifreeze inner lining to the outside of the pipe; each section of the wrapping is equipped with at least two stainless steel cable ties. The condensate drainage channel is installed along the axial direction of the pipe at the bottom of the pipe, between the aluminum foil protective outer skin and the pipe, and is used to collect the condensate after the frost melts and guide it to the drain outlet at the lowest point of the pipe.

[0021] BOG return gas pipeline (DN50, pipe specification Φ57×3.5mm, material 06Cr19Ni10 stainless steel) suitable for a certain LNG storage tank.

[0022] The aluminum foil protective outer sheath 1 is made of 0.5mm thick aluminum alloy sheet (1060-H24), and each section consists of two semi-cylindrical aluminum foil sheets joined and tightened together, with an axial length of 500mm. The outer surface of the aluminum foil sheets is anodized to form a reflective silver-white coating. Each section of the outer sheath is secured with two 304 stainless steel cable ties 8 (12mm wide, 0.4mm thick).

[0023] The thermal insulation layer 2 is made of nano-aerogel felt (SiO2 aerogel composite fiber felt), with a thickness of 20mm and a thermal conductivity of 0.018W / (m·K) (25℃). It is sleeved on the outside of the flexible antifreeze inner lining 3 in a cylindrical form. The outer surface of the aerogel felt is laminated with aluminum foil, and a 5mm air insulation gap is left between it and the aluminum foil protective outer skin 1.

[0024] The flexible antifreeze liner 3 is made of 3mm thick EPDM rubber sleeve with an inner diameter of 57mm, which fits tightly against the outer wall of pipe 4. The inner surface of the liner is laminated with a 1.5mm thick polyurethane open-cell foam microporous water-absorbing layer to absorb condensation on the pipe wall.

[0025] The split-type valve insulation cover 6 is composed of two 1.0mm thick aluminum alloy clamshell-style covers joined together, with 15mm thick aerogel insulation cotton attached to the inner wall of the cover. The two covers are connected on one side by a stainless steel hinge, and locked on the other side by two 304 stainless steel quick-release buckles 7. A Φ25mm through hole is opened at the top of the cover for the valve stem to pass through, and a silicone rubber flexible sealing ring is installed at the through hole. The axial length of the split-type valve insulation cover 6 is 300mm, covering the entire length of the valve body of valve 5 and 50mm of pipe at each end.

[0026] The condensate drainage channel 9 is a semi-circular aluminum alloy channel (20mm wide and 10mm deep), which is continuously arranged along the bottom of the pipe 4 and extends to the drain outlet at the lowest point of the pipe at both ends. It is used to drain the condensate after the frost melts and avoid accumulation.

[0027] During on-site installation, first, insert the flexible antifreeze liner 3 onto the pipe 4, then insert the thermal insulation layer 2, and finally align the aluminum foil protective outer skin 1 and secure it with stainless steel cable ties 8. At the valve 5, directly align the two halves of the split valve insulation cover 6 and lock them with the quick-release buckles 7. After installation, the outer wall temperature of the pipe increases from -120℃ (bare pipe) to approximately -85℃, significantly reducing frost formation and allowing for smooth valve operation.

[0028] When the pipeline is a liquid nitrogen storage tank pressurization pipeline (DN25, Φ32×3mm), the thickness of the thermal insulation layer 2 is reduced to 15mm, the thickness of the flexible antifreeze lining 3 is reduced to 2mm, and the axial length of the split valve insulation cover 6 is shortened to 200mm. The axial length of the segmented aluminum foil protective outer skin 1 is adjusted to 300mm. The condensate diversion channel 9 is changed to a V-shaped cross-section (channel width 15mm, channel depth 8mm).

[0029] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A segmented insulation and anti-frost protection component for gas pipeline valves, characterized in that, include: The aluminum foil protective outer skin (1) is a cylindrical aluminum foil shell that is segmented along the pipe axis and is formed by two semi-cylindrical aluminum foil sheets being joined and clamped together. The thermal insulation layer (2) is a cylindrical sleeve made of aerogel felt or polyurethane foam, which is fitted on the outside of the flexible antifreeze lining (3); The flexible antifreeze liner (3) is a thin sleeve made of silicone rubber or EPDM rubber, which is tightly wrapped around the outer wall of the pipe (4) and has a microporous water-absorbing layer on the inner surface. The split valve insulation cover (6) is made of two halves of clamshell aluminum alloy cover. The inner wall of the cover is covered with insulation cotton and is locked to the outside of the valve (5) by quick-release buckles (7). Stainless steel cable ties (8) are spaced along the pipe axis to bind and fix the aluminum foil protective outer skin (1), the thermal insulation layer (2) and the flexible antifreeze inner lining (3) to the outside of the pipe (4); The condensate diversion channel (9) is set at the bottom of the pipe (4) along the pipe axis and is located between the aluminum foil protective skin (1) and the pipe (4).

2. The gas pipeline valve segmented insulation and anti-frost coating protective assembly according to claim 1, characterized in that, The outer surface of the aluminum foil protective outer skin (1) is provided with a reflective coating, and the thickness of the aluminum foil is 0.3 to 0.8 mm.

3. The gas pipeline valve segmented insulation and anti-frost coating protective assembly according to claim 1, characterized in that, The two halves of the split valve insulation cover (6) are connected by a hinge on one side and locked by a quick-release buckle (7) on the other side; a through hole for the valve stem to pass through is provided on the top of the cover, and a flexible sealing ring is provided at the through hole.

4. The gas pipeline valve segmented insulation and anti-frost coating protective assembly according to claim 1, characterized in that, The axial length of each covered segment is 300-800mm, the butt joints between adjacent segments are staggered, and each segment is equipped with at least two stainless steel cable ties (8).

5. A segmented insulation and anti-frost protection assembly for gas pipeline valves according to claim 1, characterized in that, The condensate diversion channel (9) is a semi-circular or V-shaped aluminum alloy channel, which is continuously arranged along the bottom of the pipe and extends to the drain outlet at the lowest point of the pipe at both ends.

6. The gas pipeline valve segmented insulation and anti-frost coating protective assembly according to claim 1, characterized in that, The thermal insulation layer (2) is a nano-aerogel felt with a thermal conductivity of no more than 0.020 W / (m·K).

7. A segmented insulation and anti-frost protection assembly for gas pipeline valves according to claim 1, characterized in that, The thickness of the flexible antifreeze liner (3) is 2-5 mm, and the microporous water-absorbing layer is a polyurethane open-cell foam layer with a thickness of 1-2 mm.

8. A segmented insulation and anti-frost protection assembly for gas pipeline valves according to claim 1, characterized in that, The components are arranged in segments along the length of the pipeline and are disconnected at the valve (5), flange and instrument interface positions. The disconnected positions are covered by the split valve insulation cover (6).

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