Insulating plate structure used in cryogenic storage tanks of liquefied gas carriers

Abstract

The present invention provides an insulating plate structure for use in cryogenic storage tanks of liquefied gas carriers, which has a reliable structure, adapts to ultra-low temperature thermal expansion and cold contraction, and provides multiple sealing guarantees. [Solution] The insulating plate structure used in the cryogenic storage tank of a liquefied gas carrier includes a plurality of insulating foam blocks 1 laid on the surface of the tank body, with expansion gaps 2 remaining between adjacent foam blocks, and a U-shaped fixing frame welded to the tank body provided within the gaps, the top of which presses the foam blocks on both sides together and combines adjacent insulating plates and is fixed to the surface of the tank body, the gaps are filled with an adaptable elastic filler 4, a joint block with an extrusion reset groove is provided above the U-shaped frame and fixed by adhesive, the U-shaped fixing frame has two shapes, a female threaded sleeve and a male threaded connecting sleeve, and is manufactured by processing PUF or EPS foaming, cutting, NDT detection, and multilayer composite, and is attached by mechanical crimping, elastic filling and butyl tape or TPO heat welding sealing. This invention is applicable to storage tanks in liquefied gas carriers such as LNG and ethane, and effectively resists thermal expansion and cold contraction at temperatures from -163°C to room temperature, preventing cracks and cold bridging, and achieving a highly reliable domestically produced enclosure.

Description

Technical Field

[0005] ,

[0001] The present invention belongs to the technical field of cryogenic insulation, and specifically relates to an insulation board structure used in the liquid tanks or storage tanks of liquefied gas carriers. In particular, it is applicable to ultra-low temperature transportation or storage scenarios such as LNG (liquefied natural gas), LEG (liquefied ethylene / ethane), LPG (liquefied petroleum gas), and LAC (liquefied ammonia).

Background Art

[0002] The cargo tanks of liquefied gas carriers need to operate stably for a long time at temperatures of -40°C to -163°C or lower, and there are extremely high requirements for the sealing performance, structural strength, and thermal expansion and cold shrinkage adaptability of the thermal insulation system. The core technologies of the currently mainstream enclosure systems (such as GTT NO96, MARK III, etc.) are monopolized by foreign companies, and there are problems such as high costs and inability to control the supply chain. In China, it is urgent to develop a domestic insulation board system that has independent intellectual property rights, meets ultra-low temperature operating conditions, and has reliable crack prevention and sealing performance.

[0003] Many conventional thermal insulation boards use direct pasting of the entire foam, without fully considering the shrinkage of the material due to extreme temperature differences (which can reach several millimeters per meter), and it is easy to generate gaps at the joints, resulting in cold bridges, frosting, and even structural failure. In addition, the conventional fixing methods often rely on adhesion, lack mechanical anchors, and are prone to peeling during vibration, impact, or long-term use. Therefore, an integrated insulation board structure with mechanical crimping, elastic compensation, and multi-layer sealing functions is required.

Summary of the Invention

[0004] The purpose of the present invention is to overcome the drawbacks in the prior art and provide an insulation board structure used in the low-temperature storage tanks of liquefied gas carriers that has a reliable structure, adapts to ultra-low temperature thermal expansion and cold shrinkage, and has multiple sealing guarantees.

[0005] To achieve the above objective, this invention provides the following technical means.

[0006] This invention provides an insulating plate structure for use in cryogenic storage tanks of liquefied gas carriers.

[0007] The structure is made of PUF (polyurethane foam) or EPS (expanded polystyrene foam) and includes a plurality of insulating foam blocks laid in predetermined positions on the surface of the tank body. A gap is left between adjacent insulating foam blocks to accommodate dimensional deformation due to temperature changes. Within the aforementioned expansion gap, a U-shaped fixing frame is provided, its bottom welded to the tank body, and its top pressing the insulating foam blocks on both sides downwards to achieve mechanical anchoring. The gaps are filled with an elastic filler (e.g., EVA / PE flexible foam, melamine foam, or other flexible material), which adapts and deforms as the foam block expands and contracts, thus preventing cold bridging. A joint block is provided above the U-shaped fixing frame, and multiple vertical extrusion reset grooves are provided on top of it. These grooves are bonded to the insulating foam block and the U-shaped metal fastener by the application of adhesive, thus providing both sealing and cushioning functions.

[0008] The U-shaped fixing frame has two embodiments.

[0009] Type 1 uses an arc-welded bolt sleeve, a first screw, and a U-shaped metal fastener, resulting in a compact structure, but the height cannot be adjusted. Type 2 uses an arc-welded screw, a screw connection sleeve, and a U-shaped metal fastener. The crimping height can be adjusted using the connection sleeve, allowing it to adapt to uneven tank surfaces.

[0010] This invention has the following beneficial effects compared to the prior art. This invention effectively absorbs deformation due to temperature changes from -200°C to 40°C by leaving expansion gaps, elastic filler, and joint blocks with reset grooves, avoiding cracking of the plate body and having a strong ability to resist thermal expansion and cold contraction. The U-shaped fixing frame in this invention provides mechanical compression force and auxiliary adhesion, significantly improving vibration resistance and peel resistance, forming a double fixing guarantee. This invention uses a multi-layer sealing design, forming a quadruple sealing barrier with elastic filler, joint blocks, aluminum foil mesh cloth, and TPO waterproof layer, preventing cold bridging and moisture intrusion. This invention breaks the monopoly of foreign technologies, supports intelligent construction, and achieves localization and intelligence.

[0011] The present invention will be further described below with reference to the drawings. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram of the structure of the present invention. [Figure 2] This is a schematic diagram of the structure of the U-shaped fixing frame in the present invention. [Figure 3] This is a schematic diagram of the structure of the joint block in the present invention. [Figure 4] This is a schematic diagram of the structure of Type 1 of the U-shaped fixing frame in this invention. [Figure 5] This is a schematic diagram of the structure of Type 2 of the U-shaped fixing frame in this invention. [Modes for carrying out the invention]

[0013] The present invention will be further described below with reference to the drawings.

[0014] Example 1: Assembly of the structure As shown in Figures 1 to 5, in an insulating plate structure used in a cryogenic storage tank of a liquefied gas carrier, including insulating foam blocks 1 according to this embodiment, a plurality of insulating foam blocks 1 are laid at predetermined positions on the surface of the tank body, an expansion / contraction gap 2 is left between adjacent insulating foam blocks 1, a U-shaped fixing frame 3 is provided within the expansion / contraction gap 2, the bottom of the U-shaped fixing frame 3 is welded to the surface of the tank body, and the top of the U-shaped fixing frame 3 presses downwards against the adjacent insulating foam blocks 1 on both sides of the expansion / contraction gap 2. An elastic filler 4 is provided within the expansion / contraction gap 2, and the elastic filler 4 is capable of adapting and deforming in accordance with the expansion and contraction of the insulating foam block 1.

[0015] Preferably, the structure of the U-shaped fixing frame 3 includes an arc-welded bolt sleeve 301, a first screw 302, and a U-shaped metal fastener 30, wherein the arc-welded bolt sleeve 301 has a blind hole structure with an open top, and an internal thread is provided inside the blind hole, the bottom of the arc-welded bolt sleeve 301 is welded to the surface of the tank body in the expansion gap 2, the bottom of the U-shaped plate of the U-shaped metal fastener 30 is pressed against the top of the arc-welded bolt sleeve 301, and both of the U-shaped plates of the U-shaped metal fastener 30 The sides are extended horizontally and crimped to the adjacent insulating foam blocks 1 on both sides of the expansion gap 2, the first screw 302 has a male thread corresponding to the female thread of the blind hole of the arc welding bolt sleeve 301, the first screw 302 passes through the bottom of the U-shaped plate of the U-shaped metal fastener 30 and is connected to the female thread of the blind hole of the arc welding bolt sleeve 301, and the bolt head at the top of the first screw 302 is crimped to the U-shaped plate of the U-shaped metal fastener 30.

[0016] Furthermore, the structure of the U-shaped fixing frame 3 includes an arc welding screw 311, a screw connection sleeve 312, and a U-shaped metal fastener 30, the arc welding screw 311 is provided with a male thread, the screw connection sleeve 312 has a structure with an axial through hole, a female thread is provided in the through hole of the screw connection sleeve 312, the screw connection sleeve 312 is movably screw-connected to the arc welding screw 311, the bottom of the arc welding screw 311 is welded and fixed to the surface of the tank body in the expansion gap 2, and the arc welding screw 311 is The screw connection sleeve 312 is provided through the bottom of the U-shaped plate of the U-shaped metal fastener 30, is located on the lower side of the U-shaped metal fastener 30, both sides of the U-shaped plate of the U-shaped metal fastener 30 are extended horizontally and pressed against the adjacent insulating foam blocks 1 on both sides of the expansion gap 2, the bolt head at the top of the arc welding screw 311 is pressed against the U-shaped plate of the U-shaped metal fastener 30, the screw connection sleeve 312 is movably adjusted to the arc welding screw 311 and is pressed upward against the lower side of the U-shaped plate of the U-shaped metal fastener 30.

[0017] A columnar groove 31 is provided in the middle of the U-shaped plate of the U-shaped metal fastener 30 at a position corresponding to the bolt head, so as to match the contour of the bolt head.

[0018] In this embodiment, a joint block 5 is provided on the upper side of the U-shaped metal fastener 30, and a plurality of vertically parallel extrusion reset grooves 51 are provided on the joint block 5, and the joint block 5 is bonded and fixed to the U-shaped metal fastener 30 and the insulating foam block 1 by the application of adhesive.

[0019] Weld the arc bolts to the surface of the tank body of the low-temperature storage tank (Type 2). Lay the prefabricated PUF or EPS insulation foam block 1 at a predetermined position, and align the expansion gap 2 with the bolts. Insert it into the U-shaped metal fastener 30, tighten the screw connection sleeve 312 to press the bottom surface of the U-shaped plate upward, and crimp the columnar concave groove 31 at the top of the U-shaped plate with the bolt head. Fit the EVA foam as the elastic filler 4 into the gap 2, and further adhere the melamine joint block 5 with five extrusion reset grooves 51 upward.

[0020] Example 2: Manufacture and Installation The construction method of the insulation board structure used in the low-temperature storage tank of the liquefied gas carrier according to this example includes the following steps.

[0021] S1. Production of PUF or EPS bulk foam Regarding the production of PUF or EPS bulk foam, the PUF or EPS bulk foam is foamed by a dedicated foaming device to form a large bulk foam, and the production process, temperature, and pressure process parameters are monitored in real time. S2. Cutting of the bulk foam Move the large bulk foam after foaming completion onto the conveyor belt, accurately cut it into bulk foam of standard dimensions by an automatic cutting device, and neatly arrange the cut bulk foam on the roller conveyor. S3. Aging / curing of the bulk foam Automatically convey the cut bulk foam to the shelf system by a stacker, perform storage and aging, and complete the curing process to achieve stable physical properties. S4. Flat cutting Send the aged bulk foam to a flat cutting device, and cut the bulk foam into flat plates of uniform thickness through a plurality of cutting processes. Arrange and convey the cut flat plates on the conveying line. S5. NDT detection Place the insulation board in a non-destructive testing device, detect internal defects by an inspection unit including ultrasonic waves, and display the detection data on the monitoring screen in real time. S6. Cutting according to the outer shape and dimensions A robotic arm drives a circular saw onto the plate material that has passed the detection process, performing precise outline cutting and cutting the flat plate into insulating plates with specified dimensions and shapes. S7, adhesive application to the lower foam layer. The surface of the cut lower foam board is treated with adhesive, and a robotic arm uniformly applies the adhesive to the board surface to form a striped adhesive layer. S8, stainless steel wire mesh assembly, A stainless steel mesh is laid on the lower layer of foam board to which adhesive has been applied, completely covering the board surface with the stainless steel mesh. S9, stainless steel wire mesh adhesive application, Apply adhesive again to the stainless steel mesh to form an adhesive layer and fix the stainless steel mesh in place, then bond the top layer material. S10, assembly of the upper foam layer, The upper layer of foamed board is assembled onto a stainless steel wire mesh to form a sandwich structure. S11, adhesive application to the upper foam layer, The surface of the upper foam board is treated with adhesive to prepare it for the subsequent laying of the external protective layer. S12, stainless steel sheet or aluminum sheet or galvanized steel sheet or GRP (fiber-reinforced plastic) or TPO outer protective layer assembly, After applying adhesive to the upper foam board, a stainless steel plate, aluminum plate, galvanized steel plate, GRP (fiber-reinforced plastic), or TPO (thermoplastic polyolefin) external protective layer material is laid on top, and the coil material is unfolded to cover the entire surface of the board. S13, crimping, The assembled multilayer structure is sent to a crimping machine, where it is laminated and bonded under pressure, tightly adhering the materials of each layer. The finished crimped product then has labels and QR codes printed on its surface. S14, MES system, We will be showcasing a Manufacturing Execution System (MES) interface that displays the complete lifecycle information for the following products. Product model number, name, dimensions, Inspection results, number of products, Production date, time of arrival, time of departure. S15, Packaging and Shipping, The finished insulating boards are stacked onto pallets by a robotic arm, packaged and secured, and finally loaded onto trucks by a forklift for shipment and transport.

[0022] The method for constructing and installing the insulating plate structure used in the cryogenic storage tank of the liquefied gas carrier according to this embodiment includes the following steps.

[0023] S101, Installation and mounting of insulating boards, Scribble the surface of the tank body, and grid scribe the surface of the metal tank body of the cargo tank to mark the mounting positions for the insulating plates. S102, bolt welding, Bolts are welded to the scribed grid intersection locations to provide anchor points for the subsequent mounting of insulating plates. S103, Installation of insulating plate, Prefabricated insulating plates are attached one by one to the surface of the tank body and mechanically secured with U-shaped locking blocks to ensure tight contact between the insulating plates and the surface of the tank body. S104, Laying aluminum foil mesh cloth over the joints, After the insulating boards are installed, aluminum foil mesh cloth is laid at the joints between the boards to form a continuous sealing layer. S105, Assembly of prefabricated modules at joints, Prefabricated sealing modules made of EVA / PE modules, PUF, and melamine foam are attached to the joints, assembled, and fixed with adhesive. S106, sealing of seams with butyl tape or TPO, A TPO (thermoplastic polyolefin) waterproof coil material is welded to the seams using butyl tape or a hot air welding gun to form a complete waterproof sealing system.

[0024] Insulating boards are produced according to the above flow, and a unique 2D code is bound to each board. On-site, they are installed according to the above steps, with aluminum foil mesh cloth, PUF or PES modules, and EVA / PE sealing modules covering the seams in order, and finally TPO (thermoplastic polyolefin) waterproof coil material covered with butyl tape or a hot air welding gun.

[0025] Example 3: Application Scene This embodiment demonstrates various marine application scenarios for the insulation system described below. Main cargo tank of an LNG carrier, LNG power fuel tank, LNG refueling ship cargo tanks, LEG ethylene and ethane carrier cargo tanks, Liquefied petroleum gas (LPG) cargo tanks, LAC liquid ammonia cargo tank.

[0026] The insulating foam block 1 is mechanically fixed to the tank body by a U-shaped fixing frame 3, and the expansion gap 2 is filled with an elastic filler 4 and a joint block 5 is provided, thereby adapting to thermal expansion and cold contraction from -163°C to room temperature, ensuring long-term sealing and structural integrity.

[0027] Although embodiments of the present invention have been described in detail above with reference to the drawings, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention, within the scope of the knowledge possessed by those skilled in the art. [Explanation of Symbols]

[0028] 1. Insulating foam block 2. Expandable gap 3 U-shaped fixing frame 30 U-shaped metal fasteners 31 Columnar groove 301 Arc Welding Bolt Sleeve 302 First Screw 311 Arc welding screw 312 Screw connection sleeve 4. Elastic filler 5. Joint block 51 Extrusion reset groove

Claims

1. An insulating plate structure used in a cryogenic storage tank of a liquefied gas carrier, comprising insulating foam blocks (1), wherein a plurality of insulating foam blocks (1) are laid at predetermined positions on the surface of the tank body, expansion gaps (2) are left between adjacent insulating foam blocks (1), a U-shaped fixing frame (3) is provided within the expansion gaps (2), the bottom of the U-shaped fixing frame (3) is welded to the surface of the tank body, and the top of the U-shaped fixing frame (3) presses downwards against the adjacent insulating foam blocks (1) on both sides of the expansion gaps (2). An insulating plate structure for use in a cryogenic storage tank of a liquefied gas carrier, characterized in that an elastic filler (4) is provided in the expansion / contraction gap (2), and the elastic filler (4) is adaptable and deformable in accordance with the expansion and contraction of the insulating foam block (1).

2. The structure of the U-shaped fixing frame (3) includes an arc-welded bolt sleeve (301), a first screw (302), and a U-shaped metal fastener (30). The arc-welded bolt sleeve (301) has a blind hole structure with an open top, and a female thread is provided inside the blind hole. The bottom of the arc-welded bolt sleeve (301) is welded to the surface of the tank body within the expansion gap (2). The bottom of the U-shaped plate of the U-shaped metal fastener (30) is pressed against the top of the arc-welded bolt sleeve (301). Both sides of the U-shaped plate of the U-shaped metal fastener (30) extend horizontally and are adjacent to both sides of the expansion gap (2). The insulating plate structure used in a cryogenic storage tank of a liquefied gas carrier according to claim 1, characterized in that it is crimped to the insulating foam block (1) in contact with it, the first screw (302) has a male thread that corresponds to the female thread of the blind hole of the arc welding bolt sleeve (301), the first screw (302) passes through the bottom of the U-shaped plate of the U-shaped metal fastener (30) and is connected to the female thread of the blind hole of the arc welding bolt sleeve (301), and the bolt head at the top of the first screw (302) is crimped to the U-shaped plate of the U-shaped metal fastener (30).

3. The structure of the U-shaped fixing frame (3) includes an arc welding screw (311), a screw connecting sleeve (312), and a U-shaped metal fastener (30). The arc welding screw (311) is provided with a male thread, the screw connecting sleeve (312) has a structure with an axial through hole, a female thread is provided in the through hole of the screw connecting sleeve (312), the screw connecting sleeve (312) is movably screw-connected to the arc welding screw (311), the bottom of the arc welding screw (311) is welded and fixed to the surface of the tank body in the expansion gap (2), and the arc welding screw (311) is the bottom of the U-shaped plate of the U-shaped metal fastener (30). An insulating plate structure used in a cryogenic storage tank of a liquefied gas carrier according to claim 1, characterized in that it is provided through the portion, the screw connection sleeve (312) is located below the U-shaped metal fastener (30), both sides of the U-shaped plate of the U-shaped metal fastener (30) are extended horizontally and pressed against the adjacent insulating foam blocks (1) on both sides of the expansion gap (2), the bolt head at the top of the arc welding screw (311) is pressed against the U-shaped plate of the U-shaped metal fastener (30), the screw connection sleeve (312) is movably adjusted to the arc welding screw (311) and is pressed upward against the lower side of the U-shaped plate of the U-shaped metal fastener (30).

4. The insulating plate structure used in a cryogenic storage tank of a liquefied gas carrier according to claim 2 or 3, characterized in that a columnar groove (31) that conforms to the contour of the bolt head is provided at a position in the middle of the U-shaped plate of the U-shaped metal fastener (30) that corresponds to the bolt head.

5. An insulating plate structure used in a low-temperature storage tank of a liquefied gas carrier, as described in claim 4, characterized in that a joint block (5) is provided on the upper side of the U-shaped metal fastener (30), a plurality of extrusion reset grooves (51) are provided parallel to each other in the vertical direction on the joint block (5), and the joint block (5) is bonded and fixed to the U-shaped metal fastener (30) and the insulating foam block (1) by the application of an adhesive.

Images