A storage tank for fluorine chemical production

Abstract

The utility model relates to a storage tank technical field especially relates to a storage tank for fluorine chemical production, including jar body, the jar body includes the first layer in outside and the second layer in inside, the first layer is the impact -resistant layer of greater hardness, the second layer is the corrosion -resistant layer, still include the intermediate layer for connecting the first layer and the second layer, the intermediate layer still is used for buffering the shear force that the first layer and the second layer produced due to different thermal expansion coefficients, the thermal expansion coefficient of intermediate layer is between the first layer and the second layer, make the thermal expansion coefficient of jar body's first layer, intermediate layer and second layer change in steps or the intermediate layer realizes stress isolation of the first layer and the second layer through the elastic deformation of itself, it increases the intermediate layer between the outer layer and the inner layer of existing composite storage tank to realize the problem that the problem of the inner layer cracking appears due to the different expansion coefficient of outer layer and inner layer leads to the larger shear force at the connecting interface.

Description

Technical Field

[0001] This utility model relates to the field of storage tank technology, and in particular to a storage tank for fluorochemical production. Background Technology

[0002] To ensure rigidity and corrosion resistance, existing fluorochemical storage tanks often employ a double-layered composite structure. The outer layer is made of stainless steel to guarantee sufficient rigidity and impact resistance, while the inner layer uses polytetrafluoroethylene (PTFF) to ensure corrosion resistance. During manufacturing, the stainless steel outer layer is first welded, and then sandblasting is used to remove rust from the steel shell surface, achieving Sa2 cleanliness. Residual impurities and grease are then thoroughly removed with a cleaning agent to provide a clean substrate for subsequent bonding. The sodium-treated PTFF is then bonded to the inner wall of the stainless steel outer layer, thus forming a double-layered structure that ensures sufficient rigidity on the outside and adequate corrosion resistance on the inner layer. However, a problem with this type of storage tank is that due to the difference in thermal expansion coefficients between the inner and outer layers, significant shear forces are generated at the junction when heated, leading to cracking of the inner layer. Therefore, a new storage tank for fluorochemical production needs to be designed to address this issue. Utility Model Content

[0003] This utility model provides a storage tank for fluorochemical production. By adding an intermediate layer between the outer and inner layers of the existing composite storage tank, it alleviates the problem of cracking of the inner layer caused by large shear force at the connection interface due to the difference in expansion coefficients between the outer and inner layers.

[0004] The technical problem solved by this utility model is achieved by the following technical solution: This utility model provides a storage tank for fluorochemical production, including a tank body. The tank body includes an outer first layer and an inner second layer. The first layer is an impact-resistant layer with high hardness, and the second layer is a corrosion-resistant layer. It also includes an intermediate layer for connecting the first layer and the second layer. The intermediate layer is also used to buffer the shear force generated by the different thermal expansion coefficients of the first layer and the second layer.

[0005] Preferably, the coefficient of thermal expansion of the intermediate layer is between that of the first layer and the second layer, so that the coefficients of thermal expansion of the first layer, the intermediate layer and the second layer of the tank change in a stepwise manner.

[0006] Preferably, the intermediate layer achieves stress isolation between the first layer and the second layer through its own elastic deformation.

[0007] Preferably, there are multiple intermediate layers, and after the multiple intermediate layers connect the first layer and the second layer, the coefficient of thermal expansion of the tank gradually increases from the outside to the inside in a stepwise manner.

[0008] Preferably, the intermediate layer is connected only to a portion of the first and second layers.

[0009] Preferably, the intermediate layer completely fills the cavity formed between the first layer and the second layer or occupies only a portion of the cavity to achieve relative positional stability between the first layer and the second layer.

[0010] The beneficial effect of this utility model is that by setting an intermediate layer to buffer the shear force generated by the difference in thermal expansion coefficients between the first layer and the second layer, the problem of easy cracking of the inner layer is overcome.

[0011] The middle layer is made of a material with a thermal expansion coefficient greater than that of the outer layer and less than that of the inner layer, which can reduce shear force.

[0012] The middle layer is made of a highly elastic material, which can isolate the stress between the first and second layers, thereby avoiding the problem of the inner layer being prone to cracking. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, 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 from these drawings without creative effort.

[0014] Figure 1 This is a perspective view of the present utility model; Figure 2 This is a structural diagram of the prior art of this utility model; Figure 3 This is a structural diagram of the first embodiment of the present invention; Figure 4 This is a structural diagram of the second embodiment of the present invention; Figure 5 This is a structural diagram of the third embodiment of the present invention; Figure 6 This is a schematic diagram illustrating the use of multiple intermediate layers in this utility model.

[0015] In the diagram, 1 represents the first layer; 2 represents the middle layer; and 3 represents the second layer. Detailed Implementation

[0016] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below with reference to specific illustrations.

[0017] refer to Figures 1-5This utility model provides a storage tank for fluorochemical production, which, compared to the existing double-layer structure, adds an intermediate layer 2. In the existing storage tank, such as... Figure 2 As shown, the first layer 1 (outer layer) and the second layer 3 (inner layer) of the tank are often directly connected. When the temperature changes, for example during production when fluorochemical products at over 100 degrees Celsius are urgently introduced into the storage tank for preservation, the temperature of the outer and inner layers of the tank will rise sharply. Due to the different coefficients of thermal expansion of the first layer 1 and the second layer 3, the first layer 1 and the second layer 3 will expand to different degrees, resulting in large shear forces at the connection point, which can cause the less rigid inner layer to crack. To address this problem, this invention adds an intermediate layer 2 between the first layer 1 and the second layer 3.

[0018] like Figure 3 As shown, this utility model provides a storage tank for fluorochemical production. The tank body includes an outer first layer 1, an inner second layer 3, and an intermediate layer 2 between the first layer 1 and the second layer 3. The first layer 1 is often made of a metal material with high hardness (such as stainless steel), while the second layer 3 is made of a corrosion-resistant layer with good corrosion resistance (such as polytetrafluoroethylene). The intermediate layer 2 is located between the two to ensure a stable connection between them. At the same time, it also needs to buffer the shear force generated by the different thermal expansion coefficients of the first layer 1 and the second layer 3.

[0019] Based on the above scheme, this utility model provides a specific embodiment of the first intermediate layer 2. The coefficient of thermal expansion of the intermediate layer 2 should be between that of the first layer 1 and the second layer 3, so that the coefficients of thermal expansion of the first layer 1, intermediate layer 2 and the second layer 3 of the tank body change in a stepwise manner. When the tank body is subjected to temperature, different layers expand at different rates. Since the coefficient of expansion of the intermediate layer 2 is between that of the first layer 1 and the second layer 3, it mainly applies the gradient matching principle: by designing the intermediate layer 2, the coefficient of thermal expansion is made to be between that of the metal outer shell, such as steel, 12×10⁻⁻⁻⁶. 6 The temperature gradually transitions to an inner lining such as polyethylene, 200×10⁻ 6 / ℃, forming a continuous gradient change. For example, a three-layer structure is used: 12×10⁻ steel. 6 / ℃→Transition layer 110×10⁻ 6 / ℃→Polyethylene 200×10⁻ 6 / ℃, to avoid sudden changes in interface stress, stress dispersion mechanism: the gradient layer gradually absorbs the expansion difference through its own small deformation, and disperses the concentrated stress into small stresses at the multi-layer interface, avoiding cracks caused by local stress concentration.

[0020] Based on the above solutions, such as Figure 6As shown, in order to make the thermal expansion coefficient between the first layer 1 and the second layer 3 transition more smoothly, there are multiple intermediate layers 2. After multiple intermediate layers 2 connect the first layer 1 and the second layer 3, the thermal expansion coefficient of the tank gradually increases from the outside to the inside in a stepwise manner. This makes the transition between the multiple layers of the tank more smooth after being subjected to temperature.

[0021] Furthermore, this utility model also provides a second specific embodiment of the intermediate layer 2. The difference between this embodiment and the first embodiment is that the intermediate layer 2 is made of an elastic material (such as high-temperature resistant rubber or silicone as the intermediate layer 2) to achieve a soft connection between the first layer 1 and the second layer 3. That is, the intermediate layer 2 achieves stress isolation between the first layer 1 and the second layer 3 through its own elastic deformation. Specifically, when the first layer 1 and the second layer 3 expand differently due to the temperature of the tank, the intermediate layer 2 is squeezed. After being squeezed, the intermediate layer 2 will deform, thereby avoiding the interaction shear force between the first layer 1 and the second layer 3 during the expansion process, which would cause the second layer 3 to crack.

[0022] Furthermore, based on the two schemes mentioned above, the intermediate layer 2 can be connected only to a portion of the first layer 1 and the second layer 3, or it can be connected to the entire inner wall of the first layer 1 and the entire outer wall of the second layer 3 (i.e., the cavity formed between the first layer 1 and the second layer 3 is entirely occupied by the intermediate layer 2, or the intermediate layer 2 only occupies the cavity formed by the first layer 1 and the second layer 3), as long as the relative stability of the position between the first layer 1 and the second layer 3 can be guaranteed. Specifically, for example... Figure 4 The intermediate layer 2 is a support ring made of a material with a coefficient of thermal expansion greater than that of the first layer 1 but less than that of the second layer 3. For example, the coefficient of thermal expansion of metals such as tungsten, molybdenum, and tantalum is greater than that of stainless steel but less than that of polytetrafluoroethylene. This support ring has sufficient rigidity to not only achieve a gradient transition in the coefficient of thermal expansion but also ensure a strong connection between the first layer 1 and the second layer 3. Two or more support rings occupy only the cavity portion of the first layer 1 and the second layer 3 (i.e., the first layer 1 and the second layer 3 are only partially connected to the intermediate layer 2). At the point where the first layer 1 and the second layer 3 are connected to the intermediate layer 2, they do not contact each other during expansion, thus avoiding shear forces generated by expansion. The portion that does contact the intermediate layer 2 avoids direct contact and large shear forces through the gradient transition of the intermediate layer 2. Further, refer to... Figure 5 When the intermediate layer 2 is made of an elastic material, it can also only contact part of the first layer 1 or the second layer 3. For example, the intermediate layer 2 has grooves on the side near the second layer 3. When the intermediate layer 2 is compressed, the grooves can provide more deformation space. Alternatively, the elastic intermediate layer 2 can be placed between the second layer 3 and the first layer 1 by spiral winding, as long as the first layer 1 and the second layer 3 can be stably connected.

[0023] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above-described embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A storage tank for fluorochemical production, comprising a tank body, the tank body comprising an outer first layer (1) and an inner second layer (3), the first layer (1) being an impact-resistant layer made of stainless steel, and the second layer (3) being a corrosion-resistant layer made of polytetrafluoroethylene, characterized in that, It also includes an intermediate layer (2) for connecting the first layer (1) and the second layer (3), the intermediate layer (2) also for buffering the shear force generated by the first layer (1) and the second layer (3) due to their different coefficients of thermal expansion.

2. The storage tank for fluorochemical production according to claim 1, characterized in that, The coefficient of thermal expansion of the intermediate layer (2) is between that of the first layer (1) and the second layer (3), so that the coefficients of thermal expansion of the first layer (1), the intermediate layer (2) and the second layer (3) of the tank body change in a stepwise manner.

3. A storage tank for fluorochemical production according to claim 1, characterized in that, The intermediate layer (2) achieves stress isolation between the first layer (1) and the second layer (3) through its own elastic deformation.

4. A storage tank for fluorochemical production according to claim 2, characterized in that, The number of intermediate layers (2) is multiple, and after the multiple intermediate layers (2) connect the first layer (1) and the second layer (3), the coefficient of thermal expansion of the tank gradually increases from the outside to the inside in a stepwise manner.

5. A storage tank for fluorochemical production according to claim 2, characterized in that, The intermediate layer (2) is only connected to a portion of the first layer (1) and the second layer (3).

6. A storage tank for fluorochemical production according to claim 3, characterized in that, The intermediate layer (2) completely fills the cavity formed between the first layer (1) and the second layer (3) or occupies only a part of the cavity to achieve relative positional stability between the first layer (1) and the second layer (3).

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