A large LNG storage tank cylinder wall prestressed duct retention device and method

Abstract

This invention relates to the field of prestressed construction technology for LNG storage tank walls, and particularly to a device and method for reserving prestressed ducts in large LNG storage tank walls. The device and method include: a slipform system, comprising: slipform templates; the tank wall is formed by concrete pouring; slipform templates are provided on both the inner and outer sides of the tank wall; the slipform system can slide vertically upwards along the height of the tank wall; and a prestressed core tube, which is embedded in the tank wall and extends to the top of the tank wall. A sealing plug is detachably and securely fixed at the bottom of the prestressed core tube. Axial positioning components for gripping or releasing the prestressed core tube are provided at the top of the slipform templates on both the inner and outer sides of the tank wall. When concrete is poured, the axial positioning components grip the prestressed core tube; when the slipform system slides vertically upwards, the axial positioning components release the prestressed core tube. This invention provides a device and method for reserving prestressed ducts in LNG storage tank walls that ensures accurate positioning and unobstructed internal cavities.

Description

Technical Field

[0001] This invention relates to the field of prestressed construction technology for LNG storage tank walls, and in particular to a device and method for leaving prestressed ducts in the walls of large LNG storage tanks. Background Technology

[0002] Currently, large liquefied natural gas (LNG) storage tanks are critical equipment in energy infrastructure, and their cylindrical wall structures typically employ prestressed concrete technology to withstand enormous internal pressure and cryogenic loads. In cylindrical wall construction, the slipform process is widely used due to its continuous and efficient advantages. However, pre-installing vertical prestressed ducts that penetrate tens of meters high into the wall has remained a technical challenge.

[0003] Currently, the placement of prestressed ducts in slipform construction typically involves pre-embedded corrugated metal pipes or direct extraction of steel pipes. However, these traditional methods suffer from significant drawbacks, including difficulty in ensuring positional accuracy, high risk of duct blockage, easy damage to the pipes, and poor adaptability to the slipform process. Therefore, there is an urgent need in this field for a specialized device and method that can perfectly match the slipform construction rhythm, ensure accurate positioning of the prestressed ducts, and maintain unobstructed internal cavities without damage. Summary of the Invention

[0004] The purpose of this invention is to provide a device and method for leaving prestressed ducts in the wall of a large LNG storage tank, so as to solve the technical problems existing in the background art. The device aims to solve how to ensure the positional accuracy, internal cavity unobstructedness and structural integrity of the prestressed ducts throughout the entire height range under the conditions of continuous slipform construction, so as to achieve seamless integration with the slipform process and high-efficiency construction.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: A prestressed duct placement device for a large LNG storage tank wall includes: a tank wall and a slipform system. The slipform system includes: slipform templates. The tank wall is formed by concrete pouring. Slipform templates are provided on both the inner and outer sides of the tank wall. The slipform system can slide vertically upward along the height direction of the tank wall. It also includes: a prestressed core tube, which is embedded in the tank wall and extends to the top of the tank wall. A sealing plug is detachably sealed at the bottom of the prestressed core tube. The tops of the slipform templates on both the inner and outer sides of the tank wall are provided with axial positioning components for gripping or releasing the prestressed core tube. When pouring concrete, the axial positioning components grip the prestressed core tube; when the slipform system slides vertically upward, the axial positioning components release the prestressed core tube.

[0006] Furthermore, the prestressed core tube is an axially continuous galvanized steel pipe.

[0007] Furthermore, the sealing plug is frustum-shaped, with its upper part threaded to the bottom end of the prestressed core tube, and the lower diameter of the sealing plug being equal to the outer wall diameter of the prestressed core tube.

[0008] Furthermore, it also includes: a second sealing plug, which is a rubber plug, and the second sealing plug is detachably inserted and fixed to the top end of the prestressed core tube.

[0009] Furthermore, a pull rope is fixedly connected to the top of the second sealing plug.

[0010] Furthermore, the axial positioning assembly includes: a central positioning block and clamping blocks. The central positioning block is a rectangular block with a vertically penetrating positioning hole at the top center. The prestressed core tube moves or slides through the positioning hole. Two horizontal sliding grooves are symmetrically opened on the left and right sides of the inner middle position of the central positioning block. Two clamping blocks are provided, and the two clamping blocks are horizontally slidably connected to the two horizontal sliding grooves respectively. The opposite ends of the two clamping blocks are respectively connected to two sets of driving components for driving the two clamping blocks to clamp or loosen the prestressed core tube. The opposite ends of the two sets of driving components are respectively fixedly connected to the top of the slipform template on the inner and outer sides of the cylinder wall.

[0011] Furthermore, each of the two clamping blocks has an arc-shaped groove at one end facing each other, and the diameter of the arc-shaped groove is the same as the outer wall diameter of the prestressed core tube.

[0012] Furthermore, the driving component includes: a bearing, a screw, a sleeve, and a fixing plate. One end of the screw is rotatably mounted on the clamping block via the bearing. The screw moves through the central positioning block. The other end of the screw extends to the outside of the central positioning block and is threadedly connected to a threaded hole opened inside the sleeve. The sleeve passes vertically through and is fixedly connected to the fixing plate. The fixing plate is fixedly connected to the top of the corresponding sliding mold template.

[0013] Furthermore, the driving component also includes: reinforcing ribs and a rotating handle; a plurality of reinforcing ribs are provided on the outer side of the connection between the fixed plate and the sliding template; and a rotating handle is fixedly connected to the screw on the outer wall located between the central positioning block and the sleeve.

[0014] A method for leaving prestressed ducts in the wall of a large LNG storage tank, utilizing a device for leaving prestressed ducts in the wall of a large LNG storage tank, specifically includes the following steps: Step 1: Tie the steel reinforcement frame of the ultra-large diameter LNG storage tank wall and install the slipform system; Step 2: Install the axial positioning component onto the top of the inner and outer sliding formwork templates of the sliding formwork system; Step 3: Hoist the prestressed core tube so that it passes vertically through the positioning hole on the central positioning block, then rotate the two screws to make the two clamps hold the prestressed core tube tightly, and pour concrete. Step 4: After the concrete is poured, rotate the two screws to loosen the two clamps from the prestressed core tube, and lift the slipform system upward by 30cm. Step 5: Remove the second sealing plug, then coaxially fix another section of prestressed core tube to the top of the pre-embedded prestressed core tube, cover the second sealing plug, and then rotate the two screws respectively to make the two clamps hold the prestressed core tube tightly. Step Six: Continue pouring concrete; Step 7: Repeat steps 4 to 6 until the cylindrical wall reaches the design elevation, then stop pouring. Step 8: After the concrete has initially set, rotate the two screws to loosen the two clamps from the prestressed core tubes; then pull out all the prestressed core tubes.

[0015] Compared with the prior art, the beneficial effects of the present invention are: This invention combines an axial positioning component with a slipform system to dynamically guide and correct the prestressed core tube during the slipforming process, effectively overcoming the floating and offset of the prestressed core tube and ensuring verticality and positional accuracy throughout the entire height range. The bottom sealing plug and the top sealing plug form a double seal, fundamentally preventing the intrusion of concrete slurry. Attached Figure Description

[0016] Figure 1 This is a longitudinal sectional view of the present invention; Figure 2 This is a cross-sectional view of the invention at the clamping block; Figure 3 This is a schematic diagram of the external structure of the present invention.

[0017] The labels in the attached diagram are as follows: 1-Cylinder wall, 2-Slipform template, 3-Prestressed core tube, 4-Sealing plug one, 5-Sealing plug two, 6-Center positioning block, 601-Positioning hole, 602-Horizontal slide groove, 7-Clamping block, 8-Bearing, 9-Screw, 10-Sleeve, 1001-Threaded hole, 11-Fixing plate, 12-Reinforcing rib, 13-Rotating handle. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0019] See Figures 1-3As shown, a prestressed duct placement device for a large LNG storage tank wall includes: a tank wall 1 and a slipform system. The slipform system includes: slipform templates 2. The tank wall 1 is formed by concrete pouring. Slipform templates 2 are provided on both the inner and outer sides of the tank wall 1. The slipform system can slide vertically upward along the height direction of the tank wall 1. It also includes: a prestressed core tube 3, which is an axially continuous galvanized steel pipe. The prestressed core tube 3 is embedded in the tank wall 1 and its top extends to the top of the tank wall 1. The bottom end of the prestressed core tube 3 is detachably sealed with a sealing plug 4. The top of the slipform templates 2 on both the inner and outer sides of the tank wall 1 is provided with axial positioning components for clamping or loosening the prestressed core tube 3. When pouring concrete, the axial positioning components clamp the prestressed core tube 3. When the slipform system slides vertically upward, the axial positioning components loosen the prestressed core tube 3.

[0020] The sealing plug 4 is frustum-shaped. The upper part of the sealing plug 4 is threaded to the bottom end of the prestressed core tube 3, and the lower diameter of the sealing plug 4 is equal to the outer wall diameter of the prestressed core tube 3.

[0021] It also includes: sealing plug 25, which is a rubber plug and is detachably inserted and fixed to the top of the prestressed core tube 3.

[0022] A pull rope is fixedly connected to the top of the sealing plug 2 5, which makes it easy to pull the sealing plug 2 5 out from the top of the prestressed core tube 3.

[0023] The axial positioning assembly includes a central positioning block 6 and a clamping block 7. The central positioning block 6 is a rectangular block with a vertically penetrating positioning hole 601 at the top center. The prestressed core tube 3 moves or slides through the positioning hole 601. Two horizontal sliding grooves 602 are symmetrically opened on the left and right sides of the middle position inside the central positioning block 6. Two clamping blocks 7 are provided. The two clamping blocks 7 are horizontally slidably connected to the two horizontal sliding grooves 602 respectively. The opposite ends of the two clamping blocks 7 are respectively connected to two sets of driving components for driving the two clamping blocks 7 to clamp or loosen the prestressed core tube 3. The opposite ends of the two sets of driving components are respectively fixedly connected to the top of the slipform template 2 on the inner and outer sides of the cylinder wall 1.

[0024] Both clamping blocks 7 have arc-shaped grooves at their opposite ends, and the diameter of the arc-shaped grooves is the same as the outer wall diameter of the prestressed core tube 3.

[0025] The driving components include: bearing 8, screw 9, sleeve 10 and fixing plate 11. One end of screw 9 is rotatably mounted on clamping block 7 via bearing 8. Screw 9 moves through center positioning block 6. The other end of screw 9 extends to the outside of center positioning block 6 and is threadedly connected to threaded hole 1001 opened inside sleeve 10. Sleeve 10 is vertically passed through and fixedly connected to fixing plate 11. Fixing plate 11 is fixedly connected to the top of corresponding sliding mold template 2.

[0026] The driving component also includes: reinforcing ribs 12 and rotating handles 13. Several reinforcing ribs 12 are provided on the outer side of the connection between the fixed plate 11 and the sliding template 2. The screw 9 is fixedly connected to the rotating handle 13 on the outer wall between the central positioning block 6 and the sleeve 10.

[0027] By rotating the handle 13, the screw 9 is driven to rotate, which in turn pushes the clamping block 7 to slide horizontally within the horizontal groove 602, thereby tightening or loosening the prestressed core tube 3.

[0028] A method for leaving prestressed ducts in the wall of a large LNG storage tank, specifically including the following steps: Step 1: Tie the steel reinforcement frame of the ultra-large diameter LNG storage tank wall and install the slipform system; Step 2: Install the axial positioning component onto the top of the inner and outer sliding formwork templates 2 of the sliding formwork system; Step 3: Hoist the prestressed core tube 3 so that it passes vertically through the positioning hole 601 on the central positioning block 6. Then rotate the two screws 9 to make the two clamps 7 hold the prestressed core tube 3 tightly and pour concrete. Step 4: After the concrete is poured, rotate the two screws 9 to loosen the two clamps 7 from the prestressed core tube 3, and lift the slipform system upward by 30cm. Step 5: Remove the sealing plug 2 5, then coaxially fix the other prestressed core tube 3 to the top of the pre-embedded prestressed core tube 3, cover the sealing plug 2 5, and then rotate the two screws 9 respectively to make the two clamps 7 hold the prestressed core tube 3 tightly. Step Six: Continue pouring concrete; Step 7: Repeat steps 4 to 6 until the cylindrical wall reaches the design elevation, then stop pouring. Step 8: After the concrete has initially set, rotate the two screws 9 to loosen the two clamps 7 from the prestressed core tubes 3; then pull out all the prestressed core tubes 3; the sealing plug 1 is usually taken out with the prestressed core tubes 3, and the resulting reserved duct has a smooth inner wall, accurate dimensions, and unobstructed flow, which can be directly used for subsequent installation of formal prestressed corrugated pipes and tensioning of reinforcing bars.

[0029] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", "top / bottom", 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 limiting this invention.

[0030] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent substitutions, and improvements made by those skilled in the art to the above embodiments without departing from the scope of the technical solution of the present invention, based on the technical essence of the present invention, shall still fall within the protection scope of the technical solution of the present invention.

Claims

1. A device for retaining prestressed ducts in the wall of a large LNG storage tank, comprising: The cylindrical wall (1) and the slipform system, wherein the slipform system includes: slipform template (2), wherein the cylindrical wall (1) is formed by concrete pouring, and slipform templates (2) are provided on both the inner and outer sides of the cylindrical wall (1), and the slipform system can slide vertically upward along the height direction of the cylindrical wall (1), wherein the slipform system is characterized by further including: prestressed core tube (3), wherein the prestressed core tube (3) is embedded in the cylindrical wall (1) and its top end extends to the top of the cylindrical wall (1), and the bottom end of the prestressed core tube (3) is detachably sealed with a sealing plug (4), and the top end of the slipform templates (2) on both the inner and outer sides of the cylindrical wall (1) is provided with an axial positioning component for clamping or loosening the prestressed core tube (3); when concrete is poured, the axial positioning component clamps the prestressed core tube (3); when the slipform system slides vertically upward, the axial positioning component loosens the prestressed core tube (3).

2. The prestressed duct placement device for the wall of a large LNG storage tank according to claim 1, characterized in that: The prestressed core tube (3) is an axially continuous galvanized steel pipe.

3. The prestressed duct placement device for the wall of a large LNG storage tank according to claim 2, characterized in that: The sealing plug (4) is frustum shaped. The upper part of the sealing plug (4) is threaded to the bottom end of the prestressed core tube (3), and the lower diameter of the sealing plug (4) is equal to the outer wall diameter of the prestressed core tube (3).

4. The prestressed duct placement device for the wall of a large LNG storage tank according to claim 2, characterized in that: Also includes: Sealing plug two (5), the sealing plug two (5) is a rubber plug, the sealing plug two (5) is detachably inserted and fixed to the top of the prestressed core tube (3).

5. The prestressed duct placement device for the wall of a large LNG storage tank according to claim 4, characterized in that: The top of the sealing plug 2 (5) is fixedly connected with a pull rope.

6. The prestressed duct placement device for the wall of a large LNG storage tank according to claim 1, characterized in that: The axial positioning assembly includes a central positioning block (6) and a clamping block (7). The central positioning block (6) is a rectangular block with a vertically penetrating positioning hole (601) at the top center. The prestressed core tube (3) moves or slides through the positioning hole (601). Two horizontal sliding grooves (602) are symmetrically opened on the left and right sides of the middle position inside the central positioning block (6). Two clamping blocks (7) are provided. The two clamping blocks (7) are horizontally slidably connected to the two horizontal sliding grooves (602). The opposite ends of the two clamping blocks (7) are respectively connected to two sets of driving components for driving the two clamping blocks (7) to clamp or loosen the prestressed core tube (3). The opposite ends of the two sets of driving components are respectively fixedly connected to the top of the sliding template (2) on the inner and outer sides of the cylinder wall (1).

7. A prestressed duct placement device for a large LNG storage tank wall according to claim 6, characterized in that: Both clamping blocks (7) have circular arc grooves at their opposite ends, and the diameter of the circular arc grooves is the same as the outer wall diameter of the prestressed core tube (3).

8. A prestressed duct placement device for a large LNG storage tank wall according to claim 6, characterized in that: The driving component includes: a bearing (8), a screw (9), a sleeve (10), and a fixing plate (11). One end of the screw (9) is rotatably mounted on the clamping block (7) via the bearing (8). The screw (9) moves through the central positioning block (6). The other end of the screw (9) extends to the outside of the central positioning block (6) and is threadedly connected to a threaded hole (1001) opened inside the sleeve (10). The sleeve (10) passes vertically through and is fixedly connected to the fixing plate (11). The fixing plate (11) is fixedly connected to the top of the corresponding sliding template (2).

9. A prestressed duct placement device for a large LNG storage tank wall according to claim 6, characterized in that: The driving component also includes: reinforcing ribs (12) and rotating handles (13). Several reinforcing ribs (12) are provided on the outer side of the connection between the fixed plate (11) and the sliding template (2). The screw (9) has a rotating handle (13) fixedly connected to the outer wall between the central positioning block (6) and the sleeve (10).

10. A method for leaving prestressed ducts in the wall of a large LNG storage tank, utilizing the prestressed duct leaving device for the wall of a large LNG storage tank as described in any one of claims 1 to 9, characterized in that: Specifically, the following steps are included: Step 1: Tie the steel reinforcement frame of the ultra-large diameter LNG storage tank wall and install the slipform system; Step 2: Install the axial positioning component onto the top of the inner and outer sliding formwork templates (2) of the sliding formwork system; Step 3: Hoist the prestressed core tube (3) so that the prestressed core tube (3) passes vertically through the positioning hole (601) on the central positioning block (6), and then rotate the two screws (9) respectively so that the two clamps (7) hold the prestressed core tube (3) tightly, and pour concrete; Step 4: After the concrete is poured, rotate the two screws (9) to loosen the two clamps (7) from the prestressed core tube (3), and lift the slipform system upward by 30cm; Step 5: Remove the sealing plug 2 (5), then fix the other prestressed core tube (3) coaxially to the top of the pre-embedded prestressed core tube (3), cover the sealing plug 2 (5), and then rotate the two screws (9) respectively to make the two clamps (7) hold the prestressed core tube (3). Step Six: Continue pouring concrete; Step 7: Repeat steps 4 to 6 until the cylindrical wall reaches the design elevation, then stop pouring. Step 8: After the concrete has initially set, rotate the two screws (9) to loosen the two clamps (7) from the prestressed core tubes (3); then pull out all the prestressed core tubes (3).

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