Directional sliding tank maintenance ladder with limiting function

Abstract

The utility model discloses a directional sliding storage tank overhaul ladder with limiting function, including lower deck and the multiple deck stub column of being installed above it, every deck stub column top is connected to the upper deck through a sliding support, and the both ends of upper deck are equipped with wind load limiting column for limiting sliding support, and the middle part of upper deck is equipped with the steel ladder steel column for fixing LNG storage tank through the steel ladder stub column, and the steel ladder is installed between the multiple steel ladder steel columns, and the both ends of lower deck top are equipped with the limiting stub column for limiting upper deck, and the inner side of limiting stub column is equipped with the earthquake limiting corbel for preventing overturning. The utility model discloses lower deck, earthquake limiting corbel, limiting stub column and wind load limiting column cooperate with each other, effectively avoid the problem that when LNG storage tank displacement occurs, overhaul ladder has larger deformation and even causes the damage problem.

Description

Technical Field

[0001] This utility model relates to the field of tank maintenance ladder technology, specifically to a directional sliding tank maintenance ladder with a limiting function. Background Technology

[0002] With the continuous development of the petrochemical industry, LNG storage tanks are commonly used storage carriers. Currently, most LNG storage tanks use seismic isolation bearings, which are mostly lead-core rubber bearings or high-damping seismic isolation bearings. The stiffness of these seismic isolation bearings is very high, exceeding the stiffness of the elevator's upper structure. To allow these seismic isolation bearings to deform, their own stiffness must be overcome. Therefore, when an LNG storage tank is displaced, it can cause significant deformation or even damage to LNG storage tank elevators, whether or not they use seismic isolation bearings. The "Code for Design of Liquefied Natural Gas Receiving Terminal Engineering" GB51156-2015 clearly stipulates that the auxiliary structures of LNG storage tanks should be designed according to the Operating Basis Earthquake (OBE). Under the OBE, the horizontal displacement of LNG storage tanks using seismic isolation technology (generally above 0.15g for seismic fortification intensity of 7 degrees) can reach 200mm to 400mm. However, according to the requirements of the "Standard for Seismic Isolation Design of Buildings" GB / T51408-2021, LNG storage tanks should also consider the horizontal displacement under rare earthquakes. Under rare earthquake conditions, the displacement of LNG storage tanks can reach 400mm to 600mm, which will cause large deformations that LNG storage tank elevators without seismic isolation technology cannot adapt to, resulting in irreparable damage. Utility Model Content

[0003] This utility model addresses at least one of the aforementioned problems in the prior art by disclosing a directional sliding tank maintenance ladder with a limiting function. This utility model employs a lower support, seismic limiting brackets, limiting short columns, and wind load limiting columns working in concert. Under extreme weather conditions, the wind load limiting columns restrict small displacements of the sliding supports against their own friction. Under seismic conditions, the seismic limiting brackets and limiting short columns restrict large displacements of the sliding supports against their own friction (the larger of 1.2 times the maximum relative displacement of the tank calculated by OBE and 1.05 times the maximum relative displacement of the tank calculated by SSE) to prevent the maintenance ladder from overturning. This effectively avoids the problem of significant deformation or even damage to the maintenance ladder when the LNG storage tank shifts.

[0004] This utility model is achieved through the following technical solution:

[0005] This utility model first provides a lower foundation and multiple short columns installed above it. Each short column is connected to an upper foundation via a sliding support. The upper foundation has wind load limiting columns at both ends for limiting its position. Multiple steel ladder columns for fixing LNG storage tanks are installed in the middle of the upper foundation via steel ladder columns, and steel ladders are installed between the multiple steel ladder columns. The lower foundation has limiting short columns at both ends for limiting its position, and the inner side of the limiting short columns is provided with earthquake limiting brackets for preventing overturning.

[0006] As a further option, a camera is installed on the inside of the limiting column to monitor the displacement between the limiting column and the upper support platform, and the camera signal is connected to the external control room.

[0007] As a further option, the camera is a PTZ camera.

[0008] As a further option, the seismic limiting bracket is higher than the upper bearing platform in the horizontal direction and is located outside the wind load limiting column.

[0009] As a further option, the seismic limiting bracket is 20-25mm higher than the upper bearing platform in the horizontal direction.

[0010] As a further option, the horizontal distance between the wind load limiting column and the seismic limiting bracket is 15-25mm.

[0011] As a further option, both the upper and lower foundations are rectangular structures. There are a total of 10 short columns for the foundations, with each pair forming a group. These columns are installed in 4 groups laterally on the lower foundation, with unequal distances between adjacent groups. Eight steel ladder columns are installed in the middle of the upper foundation, with each steel ladder column and one foundation column coaxially arranged.

[0012] As a further solution, the lower foundation is equipped with a drainage channel.

[0013] As a further option, the lower pile cap is a high pile cap located on the ground, and the height of the lower pile cap is not less than 1000mm.

[0014] As a further option, steel supports are also included, with both ends of the steel supports hinged to the LNG storage tank and the steel ladder and steel column, respectively.

[0015] The features and beneficial effects of this utility model are as follows:

[0016] (1) This utility model adopts a combination of a lower support, seismic limiting bracket, limiting short column and wind load limiting column. Under extreme weather conditions, the wind load limiting column restricts the sliding support from small displacement sliding against its own friction. Under seismic action, the seismic limiting bracket and limiting short column restrict the sliding support from large displacement sliding against its own friction (the larger of 1.2 times the maximum relative displacement of the tank calculated by OBE and 1.05 times the maximum relative displacement of the tank calculated by SSE) to prevent the maintenance ladder from overturning. It effectively avoids the problem of large deformation or even damage to the maintenance ladder when the LNG storage tank is displaced.

[0017] (2) This utility model is also equipped with a camera for real-time monitoring of displacement indicators. The camera transmits the collected data to the control room to provide safety and data support for the staff.

[0018] (3) The lower support platform of this utility model is equipped with a drainage channel to avoid rainwater accumulation, facilitate drainage, prevent steel reinforcement accessories from rusting, and thus reduce maintenance costs. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the maintenance ladder as described in this embodiment of the utility model;

[0021] Figure 2 for Figure 1 Enlarged view of section A in the middle;

[0022] Figure 3 for Figure 2 Side view;

[0023] Figure 4 This is a top view of the lower support platform described in an embodiment of the present utility model;

[0024] Figure 5 This is a bottom view of the upper structure support of the maintenance ladder according to an embodiment of the present invention;

[0025] Figure 6 This is a diagram showing the positional relationship of the seismic limiting bracket described in this embodiment of the invention.

[0026] Figure 7 This is a top view of the upper support platform described in an embodiment of the present utility model.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1-Steel ladder short column; 2-Earthquake limiting bracket; 3-Limiting short column; 4-Upper pile cap; 5-Wind load limiting column; 6-Pile cap short column; 7-Lower pile cap; 8-Foundation pile; 9-Embedded part; 10-Camera; 11-Sliding bearing; 12-LNG storage tank; 13-Steel ladder steel column; 14-Steel support; 15-Steel ladder; 16-Steel railing; 17-Steel beam. Detailed Implementation

[0029] To facilitate understanding of this utility model, a more comprehensive description of this utility model will be provided below, along with embodiments of this utility model, but this does not limit the scope of this utility model.

[0030] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model 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, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0031] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] In the engineering field, existing maintenance ladders utilize lead-core rubber seismic isolation bearings or high-damping seismic isolation bearings. However, these bearings share a common characteristic: their inherent stiffness is sufficiently high. Consequently, during large vibrations or earthquakes, the upper steel frame of the bearing fails preferentially before the bearing itself deforms. Therefore, we designed a directional sliding tank maintenance ladder with a limiting function. This design ensures that the upper ladder frame does not fail preferentially under seismic loads, while simultaneously restricting displacement between the tank and the ladder through a limiting structure, thereby guaranteeing personnel safety.

[0033] A directional sliding tank maintenance ladder with limiting function, such as Figures 1 to 7 As shown, the structure includes a lower foundation 7, which is connected to the ground by multiple foundation piles 8. The middle part of the lower foundation 7 is connected to the upper foundation 4 by multiple foundation short columns 6 (bolted anchored connection), and a sliding support 11 is installed between each foundation short column 6 and the upper foundation 4. The upper foundation 4 has wind load limiting columns 5 at both ends for limiting the upper foundation. Multiple steel ladder columns 13 are installed in the middle of the upper foundation 4 through steel ladder short columns 1, and steel ladders 15 are installed between the multiple steel ladder columns 13 for fixing the LNG storage tank 12. The lower foundation 7 has limiting short columns 3 at both ends for limiting the upper foundation. Seismic limiting brackets 2 and cameras 10 are fixedly installed on the inner side of the limiting short columns 3. The seismic limiting brackets 2 are higher than the upper foundation 4 in the horizontal direction and located outside the wind load limiting columns 5. The camera 10 is located between the limiting short columns 3 and the upper foundation 4 and transmits signals to the external control room via signals.

[0034] In one embodiment, there are two sets of wind load limiting columns 5, totaling four, with one set of wind load limiting columns 5 installed on the steel structure at each end of the upper support platform 4.

[0035] In another embodiment, the upper support platform 4 and the wind load limiting column 5 are an integral structure.

[0036] In one embodiment, there are two sets of limiting short columns 3, totaling four, with one set of limiting short columns 3 installed on each end of the lower support platform 7 using steel structures.

[0037] In another embodiment, the lower support 7 and the limiting short column 3 are an integral structure.

[0038] In one embodiment, multiple foundation piles 8, multiple pile cap short columns 6, and each group of limiting short columns 3 are arranged in two columns, A and B. The transverse centerlines of the foundation piles 8, pile cap short columns 6, and limiting short columns 3 in the same column coincide, so that the bearing and stress are located on the same vertical plane, which can maximize the use of the supporting force. An earthquake limiting bracket 2 is installed on the inner side of each limiting short column 3. Similarly, the earthquake limiting bracket 2 and the wind load limiting column 5 also coincide with the transverse centerline of the limiting short column 3. The transverse centerlines of the upper pile cap 4 and the lower pile cap 7 coincide.

[0039] In this application, during an earthquake, the seismic limiting bracket 2 constrains displacement in the direction perpendicular to the steel ladder 15 and the LNG storage tank 12, while also preventing overturning of the superstructure. The wind load limiting column 5 restricts the sliding bearing from sliding under extreme weather conditions. A camera 10 monitors the distance between the limiting short column 3 and the upper support platform 4. The data monitored by the camera 10 is recorded in real time and transmitted to the control room, continuously monitoring displacement indicators and issuing early warnings, providing assurance and data support for personnel comfort and safety.

[0040] In some embodiments, the seismic limiting bracket 2 is 20-25mm higher than the upper bearing platform in the horizontal direction. The distance between the seismic limiting bracket 2 and the short steel ladder column 1 is the larger of 1.2 times the maximum relative displacement of the LNG storage tank calculated by OBE and 1.05 times the maximum relative displacement of the storage tank calculated by SSE (this value needs to be determined in combination with the structural dynamics, seismic characteristics and structural response law of the specific application scenario). The distance between the limiting short column 3 and the edge of the upper bearing platform 4 is the larger of 1.2 times the maximum relative displacement of the LNG storage tank calculated by OBE and 1.05 times the maximum relative displacement of the storage tank calculated by SSE. The horizontal distance between the wind load limiting column 5 and the seismic limiting bracket 2 is 15-25mm. The wind load limiting column 5 is used to limit the sliding of the sliding support under extreme weather conditions. When an earthquake occurs, the wind load limiting column can be destroyed.

[0041] In some embodiments, multiple short steel ladder columns 1 are installed in the middle of the upper support platform 4. Each short steel ladder column 1 is rigidly connected to a steel ladder column 13. The multiple steel ladder columns 13 are rigidly connected by steel beams 17 to form a stable frame structure. A steel ladder 15 is also installed inside the multiple steel ladder columns 13 for workers to climb. For climbing safety, steel railings 16 are welded to both sides of the steel ladder 15. The steel ladder columns 13 at both ends are connected to the LNG storage tank 12 through steel supports 14 to support and fix the LNG storage tank 12. Preferably, in order to balance the force and have relative space for movement when receiving earthquakes or other vibrations, the two ends of the steel supports 14 are hinged to the LNG storage tank 12 and the steel ladder columns 13, respectively.

[0042] In some embodiments, a pre-embedded part 9 is installed on the inner side of the limiting short column 3, and the camera 10 is welded through the pre-embedded part 9, which is conducive to the stable installation of the camera and the adjustment of the specific position according to the actual situation.

[0043] In some embodiments, the camera is a PTZ camera, preferably the Vido AU-G60 series high-speed PTZ camera. This camera uses a SONY high-performance CCD image sensor, supports multiple 485 communication protocols such as Pelco-P / D and AD, and transmits 485 signals bidirectionally. It can support the linkage control of radar and video intelligent analysis equipment, and can transmit monitoring signals to relevant equipment in the central control room to realize real-time monitoring and management of the monitoring area.

[0044] In some embodiments, steel plates are pre-embedded at the top of the short column 6 and the bottom of the upper bearing 4, respectively. The connecting plate of the sliding support 11 is fixed to the upper and lower pre-embedded steel plates by high-strength bolts, thereby completing the connection between the sliding support 11 and the top of the short column 6 and the upper bearing 4.

[0045] In some embodiments, both the limiting short column 3 and the foundation short column 6 are rigidly connected to the lower foundation 7 to ensure the integrity of the structure, the reliability of force transmission, and good seismic performance.

[0046] In some embodiments, both the upper support platform 4 and the lower support platform 7 are rectangular structures; preferably, there are a total of 8 support platform short columns 6, which are installed in 4 groups of two columns each in the horizontal direction of the lower support platform 7, and 8 steel ladder short columns 1 are installed in the middle of the upper support platform 4, with each steel ladder short column 1 and a support platform short column 6 coaxially arranged.

[0047] In some embodiments, the lower pile cap 7 is a high pile cap with a height of not less than 1000mm, which meets the requirements of punching shear pressure and is located on the ground.

[0048] In some embodiments, the lower support 7 is provided with a drainage channel to prevent rainwater from accumulating and to facilitate drainage.

[0049] In some embodiments, the sliding bearing will not move under normal operating conditions, but will slide under extreme weather conditions or seismic loads. That is, when the horizontal force on the structure caused by the seismic load or wind load exceeds the value of the dynamic friction force, the bearing will slide. Therefore, the specifications and models of the sliding bearing are selected according to the operating environment. In some embodiments, the sliding bearing 11 adopts ESB400; in other embodiments, the sliding bearing 11 adopts ESB800.

[0050] Example

[0051] Basic information of the maintenance ladder for a 220,000 LNG storage tank:

[0052] The lower foundation 7 consists entirely of rectangular plates. There are eight short columns 6 in total, arranged in groups of two, with four groups distributed laterally. The column spacing between each group is 2400mm, 3000mm, and 6000mm, respectively. The column spacing between two short columns 6 in the longitudinal direction on the lower foundation 7 is 2600mm. The distance between the maintenance ladder and the outer edge of the storage tank is 10800mm. The total height of the maintenance ladder is 67.330m, with 19 floors above ground. The dimensions of the limiting short column 3 are 800mm x 800mm, and the distance between the limiting short column 3 and the surface of the lower foundation 4 is 3500mm. The cross-section of the seismic limiting bracket 2 is as follows: upper column width 800mm, lower column width 800mm, bracket width b = 800mm, bracket width beyond the lower column c = 900mm, and bracket height h = 1400mm. The dimensions of the wind load limiting column are 300mm x 500mm.

[0053] Working principle of a directional sliding tank maintenance ladder with limit function:

[0054] Under normal operating conditions, the sliding bearing will not move. Under extreme weather conditions, wind load causes the horizontal force on the structure to exceed the value of dynamic friction. When the upper bearing platform 4 moves left and right, when the wind load limiting column 5 contacts the seismic limiting bracket 2, it will no longer slide. This allows the wind load limiting column 5 and the seismic limiting bracket 2 to cooperate in limiting the upper bearing platform 4. Under seismic action, sliding will occur. When an earthquake occurs, the left and right movement of the upper bearing platform 4 will destroy the wind load limiting column 5. At this time, the seismic limiting bracket 2 and the limiting short column 3 restrict the large displacement sliding of the sliding bearing against its own friction, thereby limiting the upper bearing platform 4. At the same time, the seismic limiting bracket 2 constrains the displacement in the direction perpendicular to the steel ladder 15 and the LNG storage tank 12. The seismic limiting bracket 2 also has the function of preventing overturning of its upper structure.

[0055] In summary, the maintenance ladder described in this application not only meets the seismic resistance and stability requirements for tank maintenance ladders in extreme weather conditions, but also records data in real time via a PTZ camera and transmits it to the control room to monitor the horizontal displacement of the flat sliding support and issue early warnings. Through the aforementioned limiting system, the maintenance ladder ensures the safety and comfort of personnel under wind loads, minor earthquakes, and moderate earthquakes, while also limiting large displacements under major earthquakes to prevent overturning and damage.

[0056] It should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A directional sliding tank maintenance ladder with limiting function, characterized in that: It includes a lower bearing platform and multiple short columns installed above it. Each short column is connected to the upper bearing platform via a sliding support. The upper bearing platform has wind load limiting columns at both ends for its limitation. In the middle of the upper bearing platform, multiple steel ladder columns for fixing the LNG storage tank are installed through steel ladder short columns, and steel ladders are installed between the multiple steel ladder columns. The lower bearing platform also has limiting short columns at both ends for limiting the upper bearing platform. The inner side of the limiting short columns is equipped with seismic limiting brackets for preventing overturning.

2. The directional sliding tank maintenance ladder with limiting function according to claim 1, characterized in that: A camera is installed on the inside of the limiting column to monitor the displacement between the limiting column and the upper support platform, and the camera signal is connected to the external control room.

3. The directional sliding tank maintenance ladder with limiting function according to claim 2, characterized in that: The camera is a PTZ camera.

4. The directional sliding tank maintenance ladder with limiting function according to claim 1, characterized in that: The seismic limiting bracket is higher than the upper bearing platform in the horizontal direction and is located outside the wind load limiting column.

5. A directional sliding tank maintenance ladder with limiting function according to claim 3, characterized in that: The seismic limiting bracket is 20-25mm higher than the upper bearing platform in the horizontal direction.

6. The directional sliding tank maintenance ladder with limiting function according to claim 3, characterized in that: The horizontal distance between the wind load limiting column and the seismic limiting bracket is 15-25mm.

7. The directional sliding tank maintenance ladder with limiting function according to claim 1, characterized in that: Both the upper and lower foundations are rectangular structures. There are a total of 10 short columns for the foundations, arranged in groups of two. They are installed in four groups laterally on the lower foundation, with unequal distances between adjacent groups. Eight steel ladder columns are installed in the middle of the upper foundation, with each steel ladder column and one foundation column coaxially arranged.

8. The directional sliding tank maintenance ladder with limiting function according to claim 1, characterized in that: The lower foundation is equipped with a drainage channel.

9. A directional sliding tank maintenance ladder with limiting function according to claim 1, characterized in that: The lower pile cap is a high pile cap located on the ground, and the height of the lower pile cap is not less than 1000mm.

10. A directional sliding tank maintenance ladder with limiting function according to claim 1, characterized in that: It also includes steel supports, with both ends of the steel supports hinged to the LNG storage tank and the steel ladder and steel column, respectively.

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