High-performance polyurethane cold storage board

Abstract

The utility model discloses a high -performance polyurethane cold storage board relates to cold storage heat preservation board material field, it includes frame, core material and two cover plates, frame is closed loop structure, both sides are equipped with double group adaptation rebate, and the front panel is equipped with pouring mouth subassembly, pouring mouth subassembly contains pipe body, the plug of sealing ring and the rubber valve of middle part with the character gap, the core material is silica aerogel layer and adheres the inner wall of frame, and the inside fills polyurethane hard bubble layer, and the cover plate covers frame up and down and rivets, and is equipped with the pressure relief hole of one -way pressure relief valve, and the core material is filled in the airtight cavity, and the aerogel layer passes through silane modified adhesive and adheres the frame, the utility model discloses leak -proof and balanced foaming pressure, and double rebate is equipped with double -layer sealing layer and reduces cold loss, and the composite core material prevents the shell from falling off, and adapts conventional equipment, and construction is efficient.

Description

Technical Field

[0001] This utility model relates to the technical field of cold storage insulation materials, specifically a high-performance polyurethane cold storage panel. Background Technology

[0002] As the core facility of low-temperature storage equipment, cold storage places extremely high demands on the insulation performance, structural stability, and ease of construction of insulation panels. Currently, most polyurethane cold storage panels on the market use a single polyurethane core material or a simple composite structure. For example, the utility model patent "A High-Performance Polyurethane Cold Storage Panel" with authorization announcement number CN 215167154 U uses a rigid polyurethane foam core material combined with an aerogel layer to achieve insulation, and a tongue-and-groove splicing structure to improve sealing.

[0003] However, the existing technology has the following shortcomings: First, the casting system design is unreasonable, lacking a leak-proof structure, which easily leads to overflow problems caused by material overflowing the casting port during the casting process. Furthermore, it lacks a pressure release mechanism, making the board prone to deformation when the foaming pressure is too high. Second, the splicing sealing performance is insufficient, employing only a single sealing layer design with no targeted sealing structure at the tongue and groove joints, making it prone to cold leakage after long-term use. Third, the stability of the core material and frame connection needs improvement, lacking an auxiliary interlocking structure and relying solely on adhesive for connection, making it prone to delamination under low-temperature repeated cycling conditions. Fourth, the casting port has poor compatibility with conventional foaming equipment, requiring customized special accessories, resulting in low construction efficiency. Summary of the Invention

[0004] To address the problems of existing polyurethane cold storage panels, such as pouring overflow, insufficient sealing, easy core material detachment, and poor construction compatibility, this utility model designs a high-performance polyurethane cold storage panel with a composite core material and optimized pouring and splicing structure.

[0005] This utility model includes a frame, a core material, and two cover plates. The frame has a closed-loop structure of "front-left-rear-right". The left and right sides of the frame are respectively provided with front and rear double sets of convex and concave tongues and grooves. The convex tongues and grooves are convex structures, and the concave tongues and grooves are concave structures adapted to the convex tongues and grooves. The front panel of the frame is provided with a pouring port assembly. The pouring port assembly includes a tube body, a plug, and a rubber flap. The tube body is fixed to the front panel and forms a pouring channel inside. The front end of the tube body is provided with an internal thread. The plug is adapted to the internal thread of the front end of the tube body and screwed in to fix it. The rear end of the tube body is provided with a seal to close its opening. The rubber valve has a slit in the middle; the core material is a composite structure, including a silica aerogel layer attached to the inner wall of the frame and a homogeneous high-density rigid polyurethane foam layer filled inside the aerogel layer. The rigid polyurethane foam layer is formed by high-pressure foaming of isocyanate and polyol in a single mixing process; two cover plates are respectively attached to the top and bottom of the frame and fixedly connected to the frame. The core material is filled in the sealed cavity enclosed by the frame and the two cover plates. The aerogel layer is attached to the inner wall of the frame by an adhesive, and the rigid polyurethane foam layer is tightly attached to the aerogel layer.

[0006] Furthermore, the frame is made of color-coated steel sheet, the base of which is cold-rolled steel sheet, and the surface coating is polyester or fluorocarbon coating; the cover plate is made of the same color-coated steel sheet as the frame, and the edge of the cover plate has an overlapping edge, which is adapted to the top and bottom contours of the frame. The cover plate and the frame are fixed by riveting, which improves the connection stability and weather resistance of the frame and the cover plate.

[0007] Furthermore, high-temperature resistant silicone baffles are provided at the base of the convex and concave tongue and groove joints on the inner side of the frame. These baffles are arranged along the length of the frame and are fixed to the inner wall of the frame. The baffles precisely define the foaming range and prevent foamed material from overflowing into the tongue and groove gaps and affecting the splicing effect.

[0008] Furthermore, a sealing layer is provided on the surface of the tongue and groove joints. This sealing layer is a double-layer structure of non-woven fabric composite on the outside of the pearl cotton base layer. The sealing layer is bonded and fixed to the surface of the tongue and groove joints with polyurethane adhesive. The double-layer sealing structure significantly improves the sealing performance at the tongue and groove joints and reduces cold leakage.

[0009] Furthermore, the cover plate is provided with a pressure relief hole with a one-way pressure relief valve along its length; the end of the plug is provided with a sealing ring, which fits and seals against the front end face of the pipe body; the adhesive is a silane-modified adhesive, the bonding strength between the aerogel layer and the inner wall of the frame is not less than 0.10MPa, the pressure relief valve can balance the pressure during the foaming process and avoid frame deformation, the sealing ring ensures the sealing reliability of the pouring port, and the silane-modified adhesive improves the bonding stability between the aerogel layer and the frame.

[0010] The advantages of this utility model are as follows: First, the rubber flap design of the pouring port assembly enables unidirectional pouring, effectively preventing material leakage. Combined with the unidirectional pressure relief valve of the cover plate, it balances the foaming pressure and completely solves the problems of overflow and deformation. Second, the double tongue and groove joints combined with the double-layer sealing layer significantly improve the splicing sealing performance and reduce the cold leakage rate. Third, the composite core material combined with silane-modified adhesive improves the thermal insulation performance while enhancing the bonding stability between the core material and the frame, preventing delamination. Fourth, the frame and cover plate use universal materials and connection methods, and the pouring port is compatible with conventional foaming equipment, greatly improving construction compatibility and efficiency. Attached Figure Description

[0011] Figure 1 This is a perspective view of the present utility model; Figure 2 This is a front view of the present utility model; Figure 3 This is a schematic diagram of the gating system assembly. In the diagram: 1-Frame; 2-Gating port assembly; 3-Core material; 4-Raised tongue and groove; 5-Concave tongue and groove; 6-Cover plate; 21-Pipe body; 22-Plug; 23-Rubber flap. Detailed Implementation

[0012] Example 1: This example implements a comprehensive implementation plan, as follows: A 0.6mm thick polyester-coated color-coated steel plate is selected as the raw material for frame 1. The base plate is a cold-rolled steel plate. A closed-loop frame 1 is fabricated using a solid blank stretching process, side tongue and groove removal, and upper and lower surface shelling. Double sets of convex tongues 4 and concave tongues 5 are processed on the left and right sides of frame 1. The convex tongue 4 has a convex structure, and the concave tongue 5 is adapted to the convex tongue 4. A pipe body 21 is fixed at a preset position on the front panel of frame 1 to form a casting port assembly 2. A rubber flap 23 with a single slot is installed at the rear end of the pipe body 21, and a plug 22 with a sealing ring is screwed into the front end. A cover plate 6 is made from a 0.4mm thick color-coated steel plate of the same material. The edges of the cover plate 6 are bent to form an overlapping edge, and two pressure relief holes with one-way pressure relief valves are opened along the length direction. The pressure relief valves open at a pressure of 0. The pressure is 0.3 MPa and the closing pressure is 0.2 MPa. A 2 mm thick silica aerogel layer is bonded to the inner wall of the frame 1 using a silane-modified adhesive, with the bonding strength controlled at 0.12 MPa. The lower cover plate 6 is riveted to the bottom of the frame 1 with rivets spaced 300 mm apart. A high-temperature resistant silicone baffle strip is attached and fixed at the root of the tongue and groove. The plug 22 is opened, and a mixture of isocyanate and polyol is injected into the frame 1 through the tube 21. The material or injection gun opens the rubber flap 23 and enters the cavity. When the pressure reaches 0.3 MPa during the foaming process, the pressure relief valve automatically releases air and closes when the pressure drops to 0.2 MPa. After foaming and curing, the plug 22 is tightened, and the upper cover plate 6 is riveted and fixed. A sealing layer of pearl cotton base composite non-woven fabric is bonded to the surface of the convex tongue and groove 4 and concave tongue and groove 5 with polyurethane adhesive to complete the cold storage panel fabrication.

[0013] Example 2: This example details the materials and connection methods of the frame and cover plate, as follows: Frame 1 is made of 0.4mm thick fluorocarbon coated color-coated steel plate. The fluorocarbon coating has superior weather resistance and is suitable for high-humidity cold storage environments. The base plate is made of cold-rolled steel plate to ensure structural strength. Cover plate 6 is made of 0.3mm thick color-coated steel plate of the same material. According to the top and bottom contours of frame 1, the edge of cover plate 6 is bent by 5mm to form an overlap edge, ensuring that the overlap edge is completely adapted to the contour of frame 1. During connection, sealant is first applied to the overlap edge of cover plate 6, and then it is aligned with the top and bottom of frame 1. Φ3mm stainless steel rivets are used for riveting, with a rivet spacing of 250mm. The rivet depth into frame 1 is 1.5 times the wall thickness of frame 1 to ensure a firm connection and prevent loosening in low-temperature environments.

[0014] Example 3: This example details the implementation of the retaining strip and sealing layer, as follows: The retaining strip is made of silicone material with a temperature resistance range of -40℃ to 200℃, with a cross-sectional size of 5mm × 10mm and a length consistent with the frame 1. During installation, a silane-modified adhesive is first applied to the root of the tongue and groove joint on the inner side of the frame 1. The retaining strip is then attached along the length of the frame 1, and micro rivets are used for fixation every 300mm to ensure that there is no gap between the retaining strip and the inner wall of the frame 1. The sealing layer uses 1mm thick pearl cotton as the base layer, with a 0.5mm thick polyester non-woven fabric laminated on the outer side. It is bonded to the surfaces of the convex tongue and groove joint 4 and the concave tongue and groove joint 5 using a special polyurethane adhesive. Before bonding, the surfaces of the convex tongue and groove joint 4 and the concave tongue and groove joint 5 are polished to remove oil and burrs. The adhesive thickness is controlled at 0.3mm. After bonding, a pressure of 0.5MPa is applied and maintained for 30 minutes to ensure that the sealing layer is tightly bonded to the convex tongue and groove joint 4 and the concave tongue and groove joint 5.

[0015] Example 4: This example details the implementation of the pouring port assembly and pressure relief hole, as follows: The pipe body 21 is made of Φ18mm stainless steel, with a length equal to the wall thickness of frame 1 + 10mm. The pipe body 21 is fixed to the front panel of frame 1 by welding, and the weld joint is filled with sealant to prevent leakage. The rubber valve 23 is made of nitrile rubber resistant to polyurethane corrosion, with a thickness of 2mm, a slot width of 1mm, and a length of 8mm. It is fixed to the rear end of the pipe body 21 by crimping. The plug 22 is made of nylon, with a Φ20mm nitrile sealing ring embedded at the end. When it mates with the internal thread at the front end of the pipe body 21, the tightening torque is controlled at 15N·m to ensure that the sealing ring fits tightly with the end face of the pipe body 21. The pressure relief hole is located at 1 / 4 and 3 / 4 of the length of the cover plate 6, with a diameter of Φ8mm. The one-way pressure relief valve is made of brass and is fixed to the pressure relief hole by threaded connection. After installation, a layer of waterproof sealant is applied to the outside of the valve body to prevent moisture from entering the cold storage.

[0016] Example 5: This example refines the preparation and bonding of the core material, as follows: A 3mm thick silica aerogel felt is used for the aerogel layer, cut to the same size as the inner wall of frame 1, with a 5mm clearance at the edges to avoid tongue and groove. A silane-modified polyurethane adhesive is used as the adhesive. After mixing the curing agent at a 1:1 mass ratio, it is evenly applied to the inner wall of frame 1 with a coating thickness of 0.2mm, covering the entire area. The aerogel felt is then bonded to the inner wall of frame 1 after adhesive application, secured with temporary clamps spaced 500mm apart, and allowed to cure for 24 hours. The polyurethane rigid foam layer is made by mixing isocyanate and polyol at a 1:1 mass ratio, injected through a high-pressure foaming machine. The foaming machine pressure is controlled at 15MPa, and the injection speed is 500ml / s, ensuring the material is evenly filled inside the aerogel layer. The foaming and curing time is controlled at 4 minutes, and the density of the core material 3 after curing is 40kg / m³.

[0017] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-performance polyurethane cold storage panel, characterized in that, include: The frame (1), core material (3), and two cover plates (6) are provided. The frame (1) is a closed-loop structure with a front-left-back-right orientation. The left and right sides of the frame (1) are provided with front and rear double sets of convex tongue and groove (4) and concave tongue and groove (5), respectively. The convex tongue and groove (4) are convex structures, and the concave tongue and groove (5) are concave structures that are adapted to the convex tongue and groove (4). The front panel of the frame (1) is provided with a pouring port assembly (2). The pouring port assembly (2) includes a tube body (21), a plug (22), and a rubber valve (23). The tube body (21) is fixed to the front panel and forms a pouring channel inside. The front end of the tube body (21) is provided with an internal thread. The plug (22) is adapted to the internal thread at the front end of the tube body (21) and screwed in to fix it. (21) A rubber valve (23) is provided at the rear end to close its opening. A slit is opened in the middle of the rubber valve (23). The core material (3) is a composite structure, including a silica aerogel layer attached to the inner wall of the frame (1) and a homogeneous high-density rigid polyurethane foam layer filled inside the aerogel layer. The polyurethane foam layer is formed by high-pressure foaming of isocyanate and polyol in a single mixing process. The two cover plates (6) are respectively covered on the top and bottom of the frame (1) and fixedly connected to the frame (1). The core material (3) is filled in the sealed cavity enclosed by the frame (1) and the two cover plates (6). The aerogel layer is attached to the inner wall of the frame (1) by an adhesive. The polyurethane foam layer is tightly attached to the aerogel layer.

2. The high-performance polyurethane cold storage panel according to claim 1, characterized in that, The frame (1) is made of color-coated steel plate, the base of which is cold-rolled steel plate, and the surface coating is polyester or fluorocarbon coating; the cover plate (6) is made of color-coated steel plate of the same material as the frame (1), and the edge of the cover plate (6) is provided with an overlapping edge, which is adapted to the top and bottom contours of the frame (1), and the cover plate (6) and the frame (1) are riveted together.

3. The high-performance polyurethane cold storage panel according to claim 2, characterized in that, The base of the protruding tongue (4) and concave tongue (5) on the inner side of the frame (1) is provided with a high-temperature resistant silicone baffle strip. The baffle strip is arranged along the length of the frame (1) and is attached and fixed to the inner wall of the frame (1).

4. The high-performance polyurethane cold storage panel according to claim 3, characterized in that, The surfaces of the convex tongue and groove (4) and the concave tongue and groove (5) are provided with a sealing layer. The sealing layer is a double-layer structure of non-woven fabric on the outside of the pearl cotton base layer. The sealing layer is bonded and fixed to the surfaces of the convex tongue and groove (4) and the concave tongue and groove (5) by polyurethane adhesive.

5. The high-performance polyurethane cold storage panel according to claim 4, characterized in that, The cover plate (6) is provided with a pressure relief hole with a one-way pressure relief valve along its length; the end of the plug (22) is provided with a sealing ring, which is fitted and sealed to the front end face of the pipe body (21); the adhesive is a silane modified adhesive, and the bonding strength between the aerogel layer and the inner wall of the frame (1) is not less than 0.10 MPa.

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