Secondary composite seal for tank floating pan

Abstract

The application discloses a kind of secondary composite seal of storage tank floating disc, belong to the technical field of oil storage tank, solve the technical problem that traditional adhesive tape sealing compensation gap is small, friction is big, metal plate sealing is poor, easy to overturn failure.The sealing is composed of edge component, floating disc float box and ringed sealing component, sealing component includes annular rubber sealing diaphragm, interval installation thin metal elastic plate, and diaphragm pressing plate, upper pressing plate and other matched pressing plate structure;Elastic plate top 90 ° bending, fixedly bent and abuts tank wall, sealing diaphragm is attached to the inside of elastic plate and fills the gap between plate, each pressing plate is layered and is fixed by bolt, and the elastic pressure of sealing diaphragm is increased by pressing plate.The application combines the advantages of two sealing modes, with the characteristics of large compensation gap, high sealing, low friction, can effectively reduce the loss of petrochemical liquid volatilization, suitable for the sealing of oil storage tank floating disc and tank wall.

Description

Technical Field

[0001] This invention relates to the field of oil storage tank technology, and in particular to a secondary composite seal for a storage tank floating roof. Technical Background

[0002] Currently, oil storage tanks, as specialized containers for various liquid media, are crucial equipment in the petrochemical industry. For petrochemical liquids such as diesel and gasoline, which are highly volatile, to reduce evaporation losses and prevent the release of evaporating oil vapors (e.g., gasoline vapors) to the outside of the tank, causing serious environmental pollution and safety hazards, a common technical approach is to install an internal floating roof above the liquid medium inside the tank. The internal floating roof rises and falls with the liquid level, effectively preventing evaporation. A sealing device is used between the floating roof and the tank wall; common sealing devices are tape seals and metal plate seals. Tape seals use tape filled with internal sponge to wrap around the floating roof; metal plate seals consist of overlapping thin, elastic metal plates installed around the outside of the floating roof. The disadvantages of tape seals are small sealing gaps and high friction; the advantages of metal plate seals are large sealing gaps, but gaps at the overlapping metal plates result in lower sealing performance than tape seals. Another disadvantage is the susceptibility to metal plate flipping, causing seal failure. To overcome the shortcomings of these two methods, this invention designs a metal plate seal with a sealing strip. Summary of the Invention

[0003] The purpose of this invention is to provide a secondary composite seal for a tank floating roof with high sealing performance. Its structure is based on a metal plate seal, but with a reduction in the number of metal plates and the addition of a continuous rubber sealing membrane behind the metal plates. Because rubber has low hardness and is easily deformable, it can easily fill the gaps between the metal plates, thereby improving the sealing performance. The basic structure is as follows: the sealing diaphragm is an annular sealing strip. The upper edge of the sealing diaphragm presses against the folded edge at the upper end of an elastic plate, and bolts are used to fix the sealing diaphragm to the folded edge at the upper end of the elastic plate, maintaining a seal. The lower edge of the sealing diaphragm overlaps with the lower end of the elastic plate and presses against the edge member, and bolts are used to fix the sealing diaphragm to the edge member, maintaining a seal. The elastic plates are installed at intervals. Where there are elastic plates, a diaphragm pressure plate is used to press on the diaphragm. Since the diaphragm is pressed against the tank wall by the elastic plates, the frictional resistance between the sealing diaphragm and the tank wall is mainly the frictional force between the elastic plate and the tank wall. The friction coefficient between the elastic plate and the tank wall is much smaller than that between the sealing diaphragm and the tank wall, thus greatly reducing the overall frictional force of the sealing diaphragm. An additional pressure plate is added on top of the diaphragm pressure plate to reduce the bending radius of the diaphragm pressure plate during deformation, thereby increasing the elastic pressure of the diaphragm pressure plate on the diaphragm. Attached Figure Description

[0004] Figure 1This is a schematic diagram of a secondary composite seal installed on a floating roof. The outer ring of the seal contacts the tank wall. To highlight the sealing structure, the tank wall is omitted from the diagram.

[0005] In the diagram: 1. Edge component, 2. Floating plate / buoy, 3. Sealing component, 11. Sealing diaphragm, 12. Elastic plate, 13. Diaphragm pressure plate, 14. Upper pressure plate.

[0006] Figure 2 This is a structural schematic diagram of the sealing component.

[0007] In the diagram: 1. Edge component, 4. Tank body, 11. Sealing diaphragm, 12. Elastic plate, 13. Diaphragm pressure plate, 14. Upper pressure plate, 15. Bottom pressure plate, 16. Pressure plate, 17. Lower pressure plate. Detailed Implementation

[0008] Figure 1 This is a schematic diagram of the secondary composite seal installed on the floating roof. As shown in the figure, the sealing diaphragm (11) is a continuous annular sealing strip. The tank (4) is omitted from the view of the sealing structure on the contact surface with the tank wall (4). Elastic plates (12) are installed at intervals. On the inner surface of the sealing diaphragm (11), a diaphragm pressure plate (13) is installed at the position corresponding to the elastic plate (12). The function of the diaphragm pressure plate (13) is to press the sealing diaphragm (11) onto the elastic plate (12) and together with the elastic plate (12) form an annular seal. An upper pressure plate (14) is installed on top of the sealing diaphragm (11). The upper pressure plate (14) is a nearly rectangular long plate with an arc edge on the outside that has the same radius as the tank wall. The function of the upper pressure plate (14) is twofold: firstly, to fix the sealing diaphragm (11) and the elastic plate (12) together; and secondly, to maintain the shape of the sealing diaphragm (11) so that the sealing diaphragm (11) can maintain a good seal with the tank wall (4) in the part without the elastic plate (12). When the elastic plate (12) is not fixed, it is a straight plate with a 90-degree bend at the top. After being fixed to the edge member (1), it bends upward and presses against the tank wall.

[0009] Figure 2 This is a schematic diagram of the sealing component. As shown in the figure, the elastic plate (12), the sealing diaphragm (11), and the diaphragm pressure plate (13) are pressed onto the tank wall (4) in sequence to form a sealing structure. The sealing with the edge component (1) is achieved by pressing the elastic plate (12) onto the edge component (1), and then stacking the sealing diaphragm (11), the lower pressure plate (17), the diaphragm pressure plate (13), and the pressure plate (16) in sequence.

[0010] In the actual installation process, the edge component (1) is first installed at the edge of the floating roof (2). Then, the elastic plate (12) is installed on the edge component (1) at intervals according to the design requirements, and the elastic plate (12) is bent upward and pressed against the tank wall. Then, the sealing diaphragm (11) is installed, with the upper edge of the sealing diaphragm (11) pressed under the folded edge of the upper end of the elastic plate (12). Then, the upper pressure plate (14) is installed on the elastic pressure plate (12), and the bottom pressure plate (15) is installed under the sealing diaphragm (11). Bolts are used to pass through the upper pressure plate (14), elastic plate (12), sealing diaphragm (11) and bottom pressure plate (15) in sequence, and nuts are used to tighten and fix them. The following installation sequence of the sealing diaphragm (11) is as follows: the lower edge of the elastic plate (12) is pressed on the edge member (1), and the sealing diaphragm (11), the lower pressure plate (17) and the pressure plate (16) are stacked in sequence. Bolts are then passed through the pressure plate (16), the lower pressure plate (17), the sealing diaphragm (11), the elastic plate (12) and the edge member (1) in sequence, and nuts are used to tighten and fix them.

[0011] The diaphragm pressure plate (13) is a rectangular plate, one end of which is fixed to the edge member (1) with bolts, and the other end is pressed on the sealing diaphragm (11). There is a pressure plate (16) on the diaphragm pressure plate. The pressure plate (16) is a rectangular plate, and its function is to prevent the reduction of the bending radius of the diaphragm pressure plate (13) and increase the pressure.

Claims

1. A secondary composite seal for a storage tank floating roof, characterized in that: Elastic plates (12) are installed at intervals on the edge members (1). The top of the elastic plates (12) is bent upwards and pressed against the tank wall. The sealing diaphragm (11) is a continuous annular sealing strip. Its upper edge is pressed below the folded edge of the upper end of the elastic plate (12), and its lower edge overlaps with the lower end of the elastic plate (12) and is pressed against the edge members (1). The diaphragm pressure plate (13) is installed on the inner side of the sealing diaphragm (11) at a position corresponding to the elastic plate (12). The sealing diaphragm (11) is pressed onto the elastic plate (12); the upper pressure plate (14) fixes the sealing diaphragm (11) and the elastic plate (12) together, while maintaining the shape of the sealing diaphragm (11); the bottom pressure plate (15) is installed below the sealing diaphragm (11) and fixed to the upper pressure plate (14); the lower pressure plate (17) and the pressure plate (16) are stacked below the sealing diaphragm (11) in sequence and fixed to the edge member (1).

2. The secondary composite seal for the floating roof of the storage tank according to claim 1, characterized in that, The sealing diaphragm (11) is made of rubber and is used to fill the gap between the elastic plates (12) to improve the sealing performance.

3. The secondary composite seal for the floating roof of the storage tank according to claim 1, characterized in that, The diaphragm plate (13) is a rectangular plate, with one end fixed on the edge member (1) and the other end pressed on the sealing diaphragm (11).

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