CN220228350U - Heat insulation structure for pipeline with cold and hot medium working alternately - Google Patents

Heat insulation structure for pipeline with cold and hot medium working alternately Download PDF

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Publication number
CN220228350U
CN220228350U CN202321467640.4U CN202321467640U CN220228350U CN 220228350 U CN220228350 U CN 220228350U CN 202321467640 U CN202321467640 U CN 202321467640U CN 220228350 U CN220228350 U CN 220228350U
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cold
layer
insulation layer
heat
pipeline
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CN202321467640.4U
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周天宇
李玖重
郜建松
张婧帆
王恒博
苏耀伦
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China Petroleum and Chemical Corp
Sinopec Engineering Group Co Ltd
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China Petroleum and Chemical Corp
Sinopec Engineering Group Co Ltd
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Abstract

The utility model provides a heat insulation structure for pipeline that cold and hot medium worked in turn, belongs to the adiabatic subassembly among the petrochemical technical field, including laying heat preservation, cold insulation layer and the protective layer at the pipeline lateral surface in proper order, lay the ripple sheet layer between heat preservation and the cold insulation layer. The corrugated plate layer is arranged between the heat insulating layer and the cold insulating layer, so that the heat insulating structure and a pipeline which relates to alternate work of cold and hot media are always attached tightly, in addition, the pressure applied to the heat insulating structure by external impact and trampling can be effectively buffered, the vibration resistance of the heat insulating structure is further improved, the moisture resistance of the heat insulating structure is improved, the heat insulating structure is firmer and more stable, the service period of the heat insulating structure is prolonged, and the production, operation and maintenance costs of enterprises are reduced.

Description

Heat insulation structure for pipeline with cold and hot medium working alternately
Technical Field
The utility model relates to an insulation structure in the technical field of petrochemical industry, in particular to an insulation structure for a pipeline with alternate working of cold and hot media.
Background
In petrochemical enterprises, due to process requirements, part of production equipment and pipelines for conveying media relate to working conditions of alternate operation of cold and hot media. For example, in the reforming extraction device, the operating temperature of production equipment in the running process is-4 ℃, the equipment cold insulation material adopts flexible foam rubber plastic products or hard polyurethane foam products and the like, and the joint of the cold insulation material is coated and sealed by mastic auxiliary materials, so that moisture is prevented from invading the cold insulation layer to cause dew condensation and icing on the outer surface of the equipment. During production downtime of the reforming extraction device, workers are required to enter the tank to replace the catalyst. Before workers enter the tank for operation, the chlorine, hydrogen sulfide and other gases harmful to human bodies in the tank are required to be purged completely, so that the requirement of the workers for entering a limited space is met. The conventional method adopts nitrogen to purge, but the nitrogen purging capability is limited, so that the condition that workers enter a limited space is difficult to achieve.
If the pipeline which relates to alternate working of cold and hot media adopts steam of 1.0MPa at 185 ℃ to purge the tank body, the purging effect is better, the condition that workers enter the operation can be met faster, but the following problems occur:
1. the recommended use temperature of cold insulation materials such as flexible foam rubber and plastic products and hard polyurethane foam products is about 80 ℃, the upper limit of the applicable temperature of mastic is about 90 ℃, and steam at 185 ℃ is used for blowing the tank body, so that the cold insulation layer is likely to fail, and when the catalyst is replaced in each production gap, the cold insulation layer is required to be replaced, and extra production cost is caused for enterprises.
2. The heat expansion and cold contraction problems can be caused by the alternate work of cold and hot media in the pipeline, the linear shrinkage rate of the heat insulation structure along with the temperature change is far smaller than that of the pipeline with the steel structure, and the heat insulation structure is not tightly attached to the pipeline;
3. along with the vibration in the pipeline operation process, if the heat insulation structure is not tightly attached, rotation and displacement can occur between two adjacent layers along with the pipeline vibration, and the two adjacent layers are mutually rubbed, so that the heat insulation structure is gradually damaged and destroyed, the sealing failure at the joint of the cold insulation layer and the loosening defect of 'upper thin and lower hollow' of the heat insulation structure are accelerated, the service period of the heat insulation structure is shortened, and the production operation cost of enterprises is increased.
Disclosure of Invention
In order to solve the problems that the heat insulation structure is invalid and the heat insulation structure is not tightly attached to the pipeline due to the fact that cold and hot media in the pipeline alternately work in the prior art, the utility model provides the heat insulation structure for the pipeline alternately work with the cold and hot media, which is suitable for equipment and pipelines which are related to the alternate work of the cold and hot media, wherein a certain thickness of heat insulation material is paved on the outer layer of the equipment or the pipeline, so that when the heat media are conveyed in the equipment or the pipeline, the outer surface temperature of the heat insulation layer (namely the highest temperature contacted by the cold insulation layer) is lower than the upper limit of the applicable temperature of the cold insulation material and auxiliary materials thereof; secondly, lay cold insulation material and its auxiliary material of certain thickness in the insulating layer surface, ensure when equipment or pipeline inside transport cold medium, the insulating layer structure seals and avoids steam invasion, and insulating layer surface temperature is higher than environment dew point temperature, avoids insulating layer surface dewfall to freeze. In addition, the corrugated plate layer is arranged between the heat preservation layer and the cold preservation layer, so that the heat insulation structure is tightly attached to the pipeline, the service period of the heat insulation structure is prolonged, the long-period safe and stable operation of the pipeline is met, and the production, operation and maintenance costs of enterprises are reduced.
The technical scheme adopted by the utility model for solving the technical problems is as follows: the utility model provides a heat insulation structure for pipeline of cold and hot medium work in turn, includes lay heat preservation, cold insulation layer and the protective layer at the pipeline lateral surface in proper order, lay the ripple sheet layer between heat preservation and the cold insulation layer.
As an optimization scheme of the heat insulation structure for the pipeline with the cold and hot medium alternately working, the heat insulation layer, the cold insulation layer and the protection layer are formed by splicing two half structures which are symmetrically arranged, the two half structures of the heat insulation layer are bound by iron wires or steel belts, the two half structures of the cold insulation layer are bonded and sealed by mastic, and the two half structures of the protection layer are connected in a metal hasp mode.
As another optimization scheme of the heat insulation structure for the pipeline with the cold and hot media alternately working, the axial length of the two-half structure is L, the projection distance between the end part of the heat insulation layer and the end part of the cold insulation layer along the axial direction is c, c is 1/5-1/20L, the angle of staggering the two adjacent splicing gaps of the heat insulation layer and the cold insulation layer along the radial direction is alpha, and the alpha is 5-90 degrees.
As another optimization scheme of the heat insulation structure for the pipeline with the cold and hot media working alternately, the heat insulation layer or the cold insulation layer is formed by stacking a plurality of layers, and when the heat insulation layer or the cold insulation layer is formed by stacking a plurality of layers, the adjacent two layers are mutually staggered along the splicing gaps in the axial direction and the radial direction.
As another optimization scheme of the heat insulation structure for the pipeline with the cold and hot media alternately working, the outer side surface of the heat insulation layer is provided with a convex-shaped protrusion or a concave-shaped groove, and the inner side surface of the adjacent outer layer is provided with a concave-shaped groove or a convex-shaped protrusion matched with the convex-shaped protrusion.
As another optimization scheme of the heat insulation structure for the pipeline with the cold and hot medium alternately working, an arc angle gamma formed by the side edge of the concave groove and the circle center of the layer where the concave groove is positioned is 5-30 degrees, and the depth e of the concave groove is 1/5-1/2 of the thickness of the layer where the concave groove is positioned.
As another optimization scheme of the heat insulation structure for the pipeline with cold and hot media working alternately, at least one cavity is arranged on the inner side surface of the cold insulation layer, and materials with lower heat conductivity than that of the cold insulation layer are filled in the cavity.
As another optimization scheme of the heat insulation structure for the pipeline with the cold and hot media working alternately, an arc angle theta formed by the side edge of the cavity and the circle center of the cold insulation layer is 5-30 degrees, and the depth f of the cavity is 1/5-1/2 of the thickness of the cold insulation layer.
As another optimization scheme of the heat insulation structure for the pipeline with the cold and hot media alternately working, the thickness of the heat insulation layer is a, and when the heat media are conveyed in the pipeline, the temperature of the outer surface of the heat insulation layer is lower than the upper limit of the applicable temperature of the cold insulation material of the cold insulation layer and auxiliary materials thereof.
As another optimization scheme of the heat insulation structure for the pipeline with cold and hot media working alternately, the thickness of the cold insulation layer is b, and when the cold media are conveyed in the pipeline, the temperature of the outer surface of the cold insulation layer is higher than the ambient dew point temperature.
Compared with the prior art, the utility model has the following beneficial effects:
1) The utility model adopts the heat insulation structure of the combination of the heat insulation layer and the cold insulation layer, and after the heat insulation structure is applied to equipment and pipelines which relate to the alternate work of cold and hot media, the heat insulation layer structure can prevent the invasion of water vapor when the cold media are conveyed, and the temperature of the outer surface of the cold insulation layer is higher than the dew point temperature of the environment, so that the dew formation and the icing of the outer surface of the heat insulation layer are avoided; when the heat medium is conveyed, the temperature of the outer surface of the heat-insulating layer (namely the highest temperature contacted by the cold-insulating layer) of the heat-insulating layer structure is lower than the upper limit of the applicable temperature of the cold-insulating material and auxiliary materials thereof. The utility model has wide application temperature range and ensures that the heat insulation layer does not lose efficacy when the cold and hot mediums alternately run.
2) According to the utility model, the corrugated plate layer is arranged between the heat insulation layer and the cold insulation layer, when cold and hot media in the pipeline alternately run to cause expansion and contraction of the pipeline, the corrugated plate layer is subjected to pressure of two layers adjacent to the heat insulation layer, so that elastic deformation is generated, the heat insulation structure is always attached tightly to the pipeline, the corrugated plate layer can effectively buffer the pressure applied to the heat insulation structure by external impact and trampling, the vibration resistance of the heat insulation structure is further improved, the moistureproof performance of the heat insulation structure is also improved, the heat insulation structure is firmer and more stable, the service period of the heat insulation structure is prolonged, and the production, operation and maintenance costs of enterprises are reduced;
3) According to the utility model, at least one cavity is arranged on the inner side surface of the cold insulation layer, materials with lower heat conductivity than that of the cold insulation layer are filled in the cavity, such as cavities, or nano aerogel and hollow glass beads are filled in the cavity, and the heat conductivity of air, nano aerogel blocks and hollow glass beads is smaller than that of the cold insulation layer, so that the purpose of reducing the overall heat conductivity of the heat insulation structure can be achieved.
Drawings
FIG. 1 is a schematic diagram of the structure of the present utility model;
FIG. 2 is an axial cross-sectional view of a two-half structure;
FIG. 3 is a radial cross-sectional view of a two-half structure;
FIG. 4 is an axial cross-sectional view of a two-layer insulation layer of a two-half structure;
FIG. 5 is a radial cross-sectional view of a two-layer insulation layer of a two-half construction;
reference numerals: 1. the heat insulation layer, 2, the cold insulation layer, 201, the cavity, 3, the protective layer, 4, the corrugated plate, D, the pipeline diameter, a, the heat insulation layer thickness, b, the cold insulation layer thickness, L, the axial length of two half structures, c, the projected distance between the end of two half structures heat insulation layer and the end of the adjacent cold insulation layer along the axial direction, D, the projected distance between the end of two half structures adjacent heat insulation layer along the axial direction, the angle that the two half structures heat insulation layer and the cold insulation layer are staggered along the two adjacent splicing gaps along the radial direction, the angle that the two adjacent heat insulation layers are staggered along the two splicing gaps along the radial direction, the arc angle formed by the side edge of the gamma, the concave groove and the center of the layer where the concave groove is located, e, the depth of the concave groove, the arc angle formed by the side edge of the cavity and the center of the cold insulation layer, f and the depth of the cavity.
Detailed Description
The technical solution of the present utility model will be further described in detail with reference to specific embodiments, and the parts of the present utility model not described in the following embodiments should be understood as techniques known or understood by those skilled in the art, such as how the cavity is filled, the structure and model of the metal buckle, and how the connection is installed.
Example 1
The heat insulation structure for the pipeline with cold and hot media working alternately comprises a heat insulation layer 1, a cold insulation layer 2 and a protection layer 3 which are sequentially paved on the outer side surface of the pipeline, wherein the heat insulation layer 1, the cold insulation layer 2 and the protection layer 3 are formed by splicing two half structures which are symmetrically arranged, and the two half heat insulation structures are shown in fig. 4 and 5, and the axial length L of the two half structures along the pipeline is 1m; the heat insulation structure adopts 2X 20mm nano aerogel felt, aluminum alloy corrugated plate and 50mm foam glass, namely a heat insulation layer 1 of the heat insulation structure adopts 2 layers of 20mm nano aerogel felt, two half structures of the heat insulation layer 1 are bound by iron wires or steel belts, a cold insulation layer 2 adopts 50mm foam glass, the two half structures of the cold insulation layer 2 are coated and sealed by mastic, the projection distance c between the end parts of the heat insulation layer of the two half structures and the end parts of the adjacent cold insulation layer along the axial direction is 50mm, and the projection distance d between the end parts of the adjacent heat insulation layers of the two half structures along the axial direction is 50mm; the two-half type structure heat preservation layer and the cold preservation layer are staggered by an angle alpha of 20 degrees along the radial adjacent two splicing gaps, the two-half type structure heat preservation layer is staggered by an angle beta of 20 degrees along the radial adjacent two splicing gaps, the protective layer 3 is made of stainless steel sheets, the two-half type structure of the protective layer 3 is connected in a metal hasp mode, and the corrugated plate layer 4 of aluminum alloy is arranged between the nano aerogel felt and the foam glass.
As shown in fig. 1, a DN300 pipeline with cold and hot media working alternately is involved, when the pipeline is purged by 1.0MPa steam with the temperature of 185 ℃ in a production gap, the temperature of the outer surface of the heat insulation layer 1, namely the highest temperature contacted by the cold insulation layer 2 is 40 ℃, is far lower than the upper limit of the applicable temperature of cold insulation materials and auxiliary materials, and when the device is in production operation, the pipeline is internally conveyed with cold media with the temperature of-4 ℃, so that the heat insulation structure can avoid water vapor invasion, and the temperature of the outer surface of the cold insulation layer 2 is higher than the ambient dew point temperature, and the outer surface can not be condensed and frozen; the corrugated board layer 4 of aluminum alloy is arranged between the nanometer aerogel felt and the foam glass, the corrugated board layer 4 is made of stainless steel, aluminum alloy and glass fiber reinforced plastic, preferably aluminum alloy, when cold and hot media in the pipeline alternately run to cause expansion and contraction of the pipeline, the corrugated board layer 4 is subjected to pressure change of two adjacent layers, and corresponding elastic deformation is generated, so that the pipeline alternately working with the cold and hot media is always attached tightly, in addition, the corrugated board layer 4 can effectively buffer the pressure applied to the heat insulation structure by external impact and trampling, the vibration resistance of the heat insulation structure is further improved, the corrugated board layer 4 also improves the moisture resistance of the heat insulation structure, the heat insulation structure is firmer and more stable, and the service period of the heat insulation structure is prolonged; the cost of production operation maintenance of enterprises is reduced.
The above is a basic embodiment of the utility model, which can be further modified, optimized and defined on the basis of the above, resulting in the following embodiments:
example 2
In order to optimize the overall thermal conductivity of the heat insulation structure, the embodiment optimizes the cold insulation layer 2 on the basis of embodiment 1, and the main structure is the same as embodiment 1, and the optimization scheme is as follows: as shown in fig. 1, fig. 2 and fig. 3, the inner layer of the cold insulation layer 2 is provided with a cavity 201, an arc angle θ formed by the side edge of the cavity 201 and the center of the cold insulation layer 2 is 10 °, the depth f of the cavity 201 is 20mm, the number of the cavities 201 is 4, the cavities in the cavity 201 are uniformly distributed along the circumference, nano aerogel or hollow glass beads, preferably nano aerogel blocks, can be filled in the cavity 201, and the overall thermal conductivity of the heat insulation structure is reduced by 10% due to the fact that the nano aerogel blocks with the thermal conductivity lower than that of the cold insulation layer 2 are filled in the cavity 201.
Example 3
In this embodiment, in order to optimize rotation and displacement of two adjacent layers of the heat insulation structure along with vibration of the pipeline, the heat insulation layer 1 and the cold insulation layer 2 are optimized on the basis of embodiment 1, and the main structure is the same as that of embodiment 1, and the optimized scheme is as follows: the outer side surface of the heat preservation layer 1 is provided with a convex protrusion or a concave groove, and the inner side surface of the adjacent outer layer is provided with a concave groove or a convex protrusion matched with the convex protrusion; as shown in fig. 4 and 5, the outer side surface of the first layer of nano aerogel felt of the heat insulation layer 1 is of a convex shape, the inner side surface of the second layer of nano aerogel felt is of a concave shape, an arc angle formed by the side edge of the concave groove and the circle center of the layer where the concave groove is positioned is 10 degrees, and the depth of the concave groove is 10mm; the outer side surface of the second layer of nanometer aerogel felt in the heat preservation layer 1 is convex, the inner side surface of the foam glass of the heat preservation layer 2 is concave, the arc angle formed by the side edge of the concave groove and the circle center of the layer where the concave groove is positioned is 10 degrees, and the depth of the concave groove is 20mm; the number of the matching of the convex type protrusions and the concave type grooves of the first layer and the second layer is 4 respectively; the first layer and the second layer are respectively provided with a convex type protuberance and a concave type groove matched with the convex type protuberance, and the convex type protuberance and the concave type groove are uniformly distributed along the circumference in sequence.
The heat preservation layer 1 and the adjacent two layers of the cold preservation layer 2 are provided with the convex protrusions and the concave grooves matched with the convex protrusions, so that the heat preservation layer 1 and the cold preservation layer 2 can be tightly combined with each other, and when the pipeline vibrates in the pipeline operation process, the adjacent two layers cannot generate rotary displacement along with the vibration of the pipeline, the heat insulation structure is firmer and more stable, the service period of the heat insulation structure is prolonged, and the heat insulation layer meets the long-period safe and stable operation of equipment.

Claims (10)

1. The utility model provides a heat insulation structure for pipeline of cold and hot medium work in turn, includes lay heat preservation (1), heat preservation (2) and protective layer (3) at pipeline lateral surface in proper order, its characterized in that: and a corrugated board layer (4) is paved between the heat insulation layer (1) and the cold insulation layer (2).
2. A heat insulating structure for a pipe in which cold and hot media are alternately operated as claimed in claim 1, wherein: the heat preservation (1), cold preservation (2) and protective layer (3) are the two half structures that the symmetry set up and splice and form, just the two half structures of heat preservation (1) are tied up with iron wire or steel band, and the two half structures of cold preservation (2) adopt the mastic bonding seal, and the two half structures of protective layer (3) adopt the metal hasp form to connect.
3. A heat insulating structure for a pipe in which cold and hot media are alternately operated as claimed in claim 2, wherein: the axial length of the two-half structure is L, the projection distance between the end part of the heat preservation layer (1) and the end part of the cold insulation layer (2) along the axial direction is c, c is 1/5-1/20L, the staggering angle between two adjacent splicing gaps along the radial direction of the heat preservation layer (1) and the cold insulation layer (2) is alpha, and the alpha is 5-90 degrees.
4. A heat insulating structure for a pipe in which cold and hot media are alternately operated as claimed in claim 1, wherein: the heat insulation layer (1) or the cold insulation layer (2) is formed by stacking a plurality of layers, and when the heat insulation layer is formed by stacking a plurality of layers, two adjacent layers are mutually staggered along the splicing gaps in the axial direction and the radial direction.
5. A heat insulating structure for a pipe in which cold and hot media are alternately operated as claimed in claim 1, wherein: the outer side surface of the heat preservation layer (1) is provided with a convex-shaped protrusion or a concave-shaped groove, and the inner side surface of the adjacent outer layer is provided with a concave-shaped groove or a convex-shaped protrusion matched with the convex-shaped protrusion.
6. A heat insulating structure for a pipe in which cold and hot media are alternately operated as set forth in claim 5, wherein: the arc angle gamma formed by the side edge of the concave groove and the center of the layer where the concave groove is located is 5-30 degrees, and the depth e of the concave groove is 1/5-1/2 of the thickness of the layer where the concave groove is located.
7. A heat insulating structure for a pipe in which cold and hot media are alternately operated as claimed in claim 1, wherein: at least one cavity (201) is arranged on the inner side surface of the cold insulation layer (2), and materials with lower heat conductivity than the cold insulation layer (2) are filled in the cavity (201).
8. A heat insulating structure for a pipe in which cold and hot media are alternately operated as set forth in claim 7, wherein: the arc angle theta formed by the side edge of the cavity (201) and the center of the cold insulation layer (2) is 5-30 degrees, and the depth f of the cavity (201) is 1/5-1/2 of the thickness of the cold insulation layer (2).
9. A heat insulating structure for a pipe in which cold and hot media are alternately operated as claimed in claim 1, wherein: the thickness of the heat preservation layer (1) is a, and when the heat medium is conveyed in the pipeline, the temperature of the outer surface of the heat preservation layer (1) is lower than the upper limit of the applicable temperature of the cold preservation material of the cold preservation layer (2) and auxiliary materials thereof.
10. A heat insulating structure for a pipe in which cold and hot media are alternately operated as claimed in claim 1, wherein: the thickness of the cold insulation layer (2) is b, and when the cold medium is conveyed in the pipeline, the temperature of the outer surface of the cold insulation layer (2) is higher than the ambient dew point temperature.
CN202321467640.4U 2023-06-09 2023-06-09 Heat insulation structure for pipeline with cold and hot medium working alternately Active CN220228350U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202321467640.4U CN220228350U (en) 2023-06-09 2023-06-09 Heat insulation structure for pipeline with cold and hot medium working alternately

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202321467640.4U CN220228350U (en) 2023-06-09 2023-06-09 Heat insulation structure for pipeline with cold and hot medium working alternately

Publications (1)

Publication Number Publication Date
CN220228350U true CN220228350U (en) 2023-12-22

Family

ID=89176124

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202321467640.4U Active CN220228350U (en) 2023-06-09 2023-06-09 Heat insulation structure for pipeline with cold and hot medium working alternately

Country Status (1)

Country Link
CN (1) CN220228350U (en)

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