A high sealing corrosion-resistant rotary joint

Abstract

The utility model discloses a kind of high sealing corrosion-resistant rotary joints, belong to equipment sealing technical field, for rotating fluorination furnace HF air intake.It includes rotating male head and rotating female head, rotating male head is provided with recess of fluorine rubber O ring and inlay in rotating female head, both are pure PTFE turning molding and are provided with through ventilation passage inside.Rotating male head has pagoda head, flat square and cylindrical structure, rotating female head has screw structure, the head of female head and middle hollow cylinder and male head corresponding structure form seal.The joint zero corrosion risk, dynamic seal is reliable, adapt 0~30rpm rotational speed and-50~200 ℃ temperature, life is 5 times of traditional metal joint, maintenance is convenient, can prevent HF leakage, guarantee production safety.

Description

Technical Field

[0001] This utility model belongs to the field of equipment sealing technology, and relates to a high-sealing, corrosion-resistant rotary joint. Specifically, it relates to a high-sealing, highly corrosion-resistant rotary joint for introducing the corrosive medium hydrogen fluoride into a rotary fluorination furnace. Background Technology

[0002] In the production of high-quality fluorides (such as lithium hexafluorophosphate for lithium batteries and high-quality rare earth fluorides), the rotary fluorination furnace is the core production equipment. Its gas inlet system needs to continuously introduce highly corrosive hydrogen fluoride gas under dynamic rotation conditions. Stable and safe introduction of hydrogen fluoride gas into the rotary fluorination furnace is a key link to ensure smooth production.

[0003] However, existing rotary joints have many problems and are difficult to meet production needs. (1) Poor corrosion resistance: Traditional rotary joints are mostly made of metal, while hydrogen fluoride is extremely corrosive to metal and will quickly corrode the metal joint, resulting in a short service life. Corrosion damage usually occurs after a short period of use, which greatly increases the risk of gas leakage. This not only affects production efficiency but also poses a serious threat to production safety. (2) Sealing failure: Under the dynamic rotation conditions of the rotary fluorination furnace, the seals of traditional rotary joints are easily worn due to friction, and the sealing performance gradually decreases, eventually leading to sealing failure. Sealing failure will cause hydrogen fluoride gas leakage. Hydrogen fluoride gas is highly toxic and corrosive. After leakage, it will not only harm the health of operators but also cause serious pollution to the surrounding environment and affect the normal operation of production. (3) Frequent maintenance: Due to the poor corrosion resistance and easy sealing failure of traditional metal rotary joints, frequent shutdowns are required for replacement and maintenance. Frequent shutdowns will not only interrupt the production process, reduce production efficiency, and increase production costs, but may also cause other production problems due to improper operation during shutdown and restart.

[0004] Although some joints use PTFE lining, they generally suffer from problems such as a single dynamic sealing structure and the possibility of the sealing structure shifting during the operation of the rotary fluorination furnace. Therefore, there is an urgent need for a rotary joint that combines high sealing performance with resistance to hydrogen fluoride corrosion, ensuring that the sealing structure does not shift during the operation of the rotary fluorination furnace, thus guaranteeing the safe and stable operation of the rotary fluorination furnace. Summary of the Invention

[0005] The purpose of this invention is to provide a highly leak-proof, corrosion-resistant rotary joint for hydrogen fluoride inlet in a rotary fluorination furnace. This aims to solve problems such as corrosion leakage and unreliable dynamic sealing in existing rotary joints. By optimizing the structural design and selecting suitable materials, it achieves leak-proof hydrogen fluoride inlet, ensuring the safe and stable operation of the rotary fluorination furnace, reducing maintenance costs, improving production efficiency, and protecting operator safety and the surrounding environment from pollution. This invention achieves its purpose through the following specific technical solutions.

[0006] A high-sealing, corrosion-resistant rotary joint includes a male rotary head and a female rotary head. The male rotary head has a groove with an O-ring seal inside. The male rotary head is embedded in the female rotary head. Both the male and female rotary heads have internal venting channels that extend through both ends of the joint. By creating a groove with an O-ring seal, a sealing structure is constructed. Combined with the through venting channels, this ensures stable flow of hydrogen fluoride gas while preventing gas leakage.

[0007] Furthermore, the rotating male connector is integrally machined from pure polytetrafluoroethylene (PTFE). Pure PTFE has excellent corrosion resistance, resisting long-term corrosion from hydrogen fluoride, avoiding the problems of short lifespan and high leakage risk caused by corrosion in traditional metal connectors, thus extending the service life of the rotating connector and reducing leakage risks.

[0008] Furthermore, the head of the rotating male connector is equipped with a pagoda-shaped head structure, which is used for a sealed connection with the PTFE hose. The pagoda-shaped head structure facilitates precise mating with the PTFE hose and enables a reliable sealing connection, preventing hydrogen fluoride gas leakage at the joint and hose connection point, and ensuring the airtightness of gas transmission.

[0009] Furthermore, the middle section of the rotating male head has a flat rectangular structure and a cylindrical structure. The two sides of the flat rectangular structure are used for external clamps, and the cylindrical structure is embedded in the head of the rotating female head. The flat rectangular structure, together with the external clamps, can fix the rotating male head and prevent it from rotating during operation; the cylindrical structure, embedded in the head of the rotating female head, can restrict the forward and backward movement of the rotating male head, so that the rotating male head forms a stable static structure, ensuring that the relative position of the two is stable when the rotating female head rotates, and avoiding the impact of the male head movement on the sealing effect and gas transmission.

[0010] Furthermore, the entire rotary female connector is machined from pure polytetrafluoroethylene (PTFE). The rotary female connector and the rotary male connector are made of the same material, pure PTFE, ensuring excellent corrosion resistance of the entire rotary joint and making the entire media flow channel a PTFE structure, providing all-around protection against hydrogen fluoride corrosion.

[0011] Furthermore, the rotating female head is provided with a threaded structure, which is used for threaded connection with the 316L stainless steel rotating shaft. The threaded structure realizes a reliable connection between the rotating female head and the 316L stainless steel rotating shaft, so that the rotating female head rotates synchronously with the rotating shaft, forming a dynamic structure to meet the working requirements of the dynamic rotation of the rotary fluorination furnace.

[0012] Furthermore, the O-ring is a fluororubber O-ring. Fluororubber O-rings have excellent corrosion resistance and high temperature resistance, and can adapt to the corrosive environment of hydrogen fluoride and the temperature fluctuations that may occur during the operation of the rotary fluorination furnace. Compared with ordinary rubber O-rings, they have a longer service life, more stable sealing performance, and effectively prevent gas leakage.

[0013] Furthermore, the head of the rotating female connector is a hollow cylinder, forming a sealing structure with the cylindrical structure in the middle section of the rotating male connector. The precise fit between the hollow cylinder at the head of the rotating female connector and the cylindrical structure in the middle section of the rotating male connector creates an additional sealing surface, further enhancing the sealing performance between the rotating male and female connectors, reducing the possibility of hydrogen fluoride gas leakage, and improving overall sealing reliability.

[0014] Furthermore, the central part of the rotating female head is a hollow cylinder, forming a sealing structure with the tail structure of the rotating male head. This sealing structure, along with the head sealing structure and the O-ring seal within the groove, constitutes a multi-layered sealing system, significantly improving overall sealing performance. Even under dynamic rotation conditions, it effectively prevents hydrogen fluoride gas leakage, adapting to the working environment of the rotary fluorination furnace.

[0015] Furthermore, the rotating male end has two or more grooves, and the O-ring is an ePTFE (expanded polytetrafluoroethylene) fluororubber O-ring. The two or more grooves and corresponding O-rings further enhance the sealing effect, and the ePTFE fluororubber material has better sealing properties.

[0016] This utility model has the following beneficial technical effects: (1) Zero corrosion risk: The medium flow channel is made of PTFE, which is resistant to long-term HF corrosion. (2) Reliable dynamic sealing: The combination of two or more seals (groove with fluororubber O-ring) is suitable for speeds of 0 to 30 rpm and temperature fluctuations of -50 to 200℃. (3) Long service life: The self-lubricating properties of PTFE reduce wear and the service life is more than 5 times that of traditional metal joints. (4) Safe and environmentally friendly: Completely eliminates HF leakage and ensures production safety. (5) Convenient maintenance: Modular design allows for replacement within 30 minutes. Attached Figure Description

[0017] Figure 1 This is a cross-sectional schematic diagram of the rotary joint provided by this utility model.

[0018] Figure 2 This is a schematic diagram of the overall structure of the rotating male connector provided by this utility model.

[0019] Figure 3 This is a schematic diagram of the overall structure of the rotating female head provided by this utility model.

[0020] In the diagram: 1. Head of the male rotating connector; 2. Middle section of the male rotating connector; 3. Tail of the male rotating connector; 4. Vent channel; 5. Head of the female rotating connector; 6. Middle section of the female rotating connector; 7. Tail of the female rotating connector; 8. O-ring seal; 9. Flat square structure; 10. Cylindrical structure; 11. Pagoda head structure; 12. Threaded structure; Detailed Implementation

[0021] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the protection scope of this utility model.

[0022] 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 the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and 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" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance, quantity, or position.

[0023] 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 according to the specific circumstances.

[0024] The rotary joint provided by this utility model is described in detail below from three aspects: component processing, assembly process, and performance testing.

[0025] 1. Parts processing High-quality PTFE rods are selected, and the rotating male head is machined using turning technology according to the design dimensions and precision requirements. During the turning process, the dimensional accuracy and surface finish of the head 1, pagoda head structure 11, middle flat square structure 9, cylindrical structure 10, and the two grooves at the tail 3 of the rotating male head are strictly controlled to ensure that each structure meets the design requirements. In particular, the dimensions of the two grooves must match the O-ring seal 8 that will be installed later to ensure the sealing effect.

[0026] High-quality polytetrafluoroethylene (PTFE) rods are also selected, and the rotating female head is machined using a turning process. During the turning process, the dimensional accuracy, inner wall smoothness, and thread structure accuracy of the head 5 and the central hollow cylinder of the rotating female head are carefully ensured. This ensures that the head hollow cylinder can precisely fit with the cylindrical structure 10 of the central section 2 of the rotating male head, that the central hollow cylinder can fit well with the tail 3 of the rotating male head, and that the thread structure 12 can reliably connect with the 316L stainless steel rotating shaft.

[0027] Select fluororubber materials that meet the standards to process and manufacture O-ring seals 8. ePTFE fluororubber material is preferred to ensure that the dimensional accuracy, elasticity and corrosion resistance of O-ring seals 8 meet the requirements and can perfectly match the groove on the tail 3 of the rotating male head to achieve a reliable seal.

[0028] 2. Assembly process Before assembly, the tail 3 of the finished rotating male head, the head 5 of the rotating female head, and the O-ring 8 are cleaned to remove impurities and oil stains from the surface, so as to prevent impurities from affecting the sealing performance or damaging the components.

[0029] First, insert the two O-rings 8 into the two grooves at the tail 3 of the rotating male head, ensuring that the O-rings 8 are properly installed in the grooves without twisting or deformation, in order to guarantee the sealing effect.

[0030] Next, slowly insert the tail 3 of the rotating male head into the head 5 of the rotating female head. During the insertion process, ensure that the central axis of the rotating male head and the rotating female head are aligned to avoid damage to the components or affect the sealing performance due to misalignment, until the cylindrical structure 10 and the tail structure 3 of the rotating male head are fully engaged with the head 5 and the central hollow cylinder of the rotating female head, respectively.

[0031] Then, connect the PTFE hose to the pagoda head structure 11 of the head 1 of the rotating male connector. When connecting, ensure that the hose fits tightly with the pagoda head structure. You can use clamps or other auxiliary methods to further strengthen the seal and prevent gas leakage.

[0032] Then, the head 5 of the rotating head is threaded to the 316L stainless steel rotating shaft by means of the thread structure 12 on the head 5 of the rotating head. During the connection process, ensure that the threads are tightened to avoid loosening, so as to ensure that the rotating head can rotate synchronously and stably with the rotating shaft.

[0033] Finally, an external clamp is used to hold the flat rectangular structure 9 of the middle section 2 of the rotating male head to prevent the rotating male head from moving during the operation of the rotary fluorination furnace.

[0034] 3. Performance Testing After assembly, an airtightness test was performed on the rotary joint. The venting channel 4 of the rotary joint was connected to a hydrogen fluoride gas supply device, and hydrogen fluoride gas at a pressure of 0.05 MPa was introduced into the venting channel 4. A leak detector was used to perform static leakage detection on each sealing part of the rotary joint.

[0035] Subsequently, dynamic performance tests were conducted on the rotary joint. It was installed on a test bench simulating a rotary fluorination furnace. The rotation speed of the test bench was controlled to vary within the range of 0 to 30 rpm, and the temperature fluctuated within the range of -50 to 200℃. Hydrogen fluoride gas at 0.05 MPa was continuously introduced, and the leakage rate was tested again after a period of operation.

[0036] After passing static leakage detection and dynamic performance testing, it can be used as the hydrogen fluoride inlet for rotary fluorination furnaces.

[0037] Although embodiments of the present invention have been shown and described above, it is understood that these embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and alterations to the above embodiments within the scope of the present invention without departing from its principles and spirit. The scope of protection of the present invention is defined by the claims and their equivalents.

Claims

1. A high containment corrosion resistant rotary union, characterized by, It includes a rotating male head and a rotating female head. The rotating male head has a groove and an O-ring seal (8) is provided in the groove. The rotating male head is embedded in the rotating female head. Both the rotating male head and the rotating female head have ventilation channels (4) inside, and the ventilation channels pass through both ends of the rotating male head and the rotating female head. The head (1) of the rotating male head has a pagoda head structure (11).

2. The high containment corrosion resistant rotary union of claim 1, wherein, The rotating male head is integrally machined from pure polytetrafluoroethylene.

3. The high containment corrosion resistant rotary union of claim 1, wherein, The middle section (2) of the rotating male head is provided with a flat square structure (9) and a cylindrical structure (10), and the cylindrical structure (10) is embedded in the head (5) of the rotating female head.

4. The high containment corrosion resistant rotary union of claim 1, wherein, The rotating head is integrally machined from pure polytetrafluoroethylene.

5. The high containment corrosion resistant rotary union of claim 1, wherein, The rotating female head is provided with a threaded structure (12).

6. The high containment corrosion resistant rotary union of claim 1, wherein, The O-ring (8) is a fluororubber O-ring.

7. The high containment corrosion resistant rotary union of claim 1, wherein, The head (5) of the rotating female head is a hollow cylinder, and forms a sealed structure with the cylindrical structure (10) of the middle section (2) of the rotating male head.

8. The high containment corrosion resistant rotary union of claim 1, wherein, The middle part (6) of the rotating female head is a hollow cylinder, and it forms a sealed structure with the tail part (3) of the rotating male head.

9. The high containment corrosion resistant rotary union of claim 1, wherein, The rotating male head has two or more grooves, and the O-ring (8) is an ePTFE fluororubber O-ring.

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