Novel PTA (pure terephthalic acid) device oxidation drying machine gas loading fan inlet and outlet expansion joint

Abstract

The utility model belongs to the technical field of pipeline compensation equipment, and discloses a novel PTA (pure terephthalic acid) device oxidation drying machine gas loading fan inlet and outlet expansion joint which comprises a corrugated pipe, a guide cylinder and a screw assembly a. The corrugated pipe is sleeved outside the guide cylinder along the medium inlet and outlet direction of the guide cylinder, and a PTEE layer is fixedly arranged on the inner wall surface of the corrugated pipe; the edge of the medium inlet side of the guide cylinder is provided with a guide cylinder flange which is turned outwards, and the edges of the medium inlet side and the medium outlet side of the corrugated pipe are provided with corrugated pipe flanges which are turned outwards; flange rings are arranged on the inner side surfaces of the flangings of the corrugated pipe on the medium inlet side and the medium outlet side; the flangings of the guide cylinder on the medium inlet side, the flangings of the corrugated pipe and the flange rings are fixedly connected through screw assemblies a; and the corrugated pipe turnup and the flange ring on the medium outlet side are fixedly connected through a screw assembly b. The expansion joint can effectively cope with challenges of bromide ions and other corrosive substances, and long-term stable operation of the expansion joint is ensured.

Description

Technical Field

[0001] This utility model belongs to the technical field of pipeline compensation equipment, specifically relating to a novel expansion joint for the inlet and outlet of the carrier gas fan of a PTA unit oxidation dryer. Background Technology

[0002] PTA (Purified Terephthalic Acid) plants are a key component of the chemical industry, specifically used for the production of PTA. This plant converts petrochemical feedstocks into PTA through a series of chemical reactions. In the PTA production process, wet materials must undergo drying to meet specific product quality standards. Oxidation dryers, as highly efficient drying equipment, play a central role in this process. They utilize hot air or steam as the drying medium, exchanging heat with the wet materials to cause the moisture or solvents in the materials to evaporate and be removed, thus achieving the drying of the materials.

[0003] The inlet and outlet expansion joints of the carrier air blower in an oxidation dryer are crucial components connecting the blower to the piping system. They primarily compensate for thermal expansion and contraction of the piping caused by temperature changes, vibration, or equipment displacement, ensuring stable system operation. However, during PTA production, the generation of bromide ions and the presence of acidic gases or liquids in the wet materials pose a significant challenge to commonly used metal bellows expansion joints. These corrosive substances can easily lead to perforation of the bellows, shortening the expansion joint's lifespan and potentially causing environmental pollution or personnel safety risks.

[0004] Although patent CN205560096U proposes an expansion joint design that differentiates the two ends of the expansion joint by adding a flange at one end, preventing installation errors, improving airtightness, reducing the number of parts, and enhancing reliability, this patent does not offer specific optimization measures for the corrosion of metal bellows by bromide ions. Furthermore, the thin steel plate guide tube design used in this patent may actually exacerbate the corrosion risk of the metal bellows. Utility Model Content

[0005] To overcome the shortcomings of existing technologies, this utility model provides a novel expansion joint for the inlet and outlet of the carrier gas fan of a PTA unit oxidation dryer, which can effectively cope with the challenges of bromide ions and other corrosive substances, and ensure the long-term stable operation of the expansion joint.

[0006] The above-mentioned objective of this utility model is achieved through the following technical solution:

[0007] This utility model provides a novel expansion joint for the inlet and outlet of the carrier gas fan in a PTA unit oxidation dryer, comprising a bellows, a guide tube, and screw assembly a. The guide tube is hollow inside for the flow of the drying medium. The bellows is sleeved on the outside of the guide tube along the medium inlet and outlet direction, and a PTEE layer is fixedly provided on the inner wall of the bellows. The guide tube has an outwardly flared edge on the medium inlet side, and the bellows also has outwardly flared edges on both the medium inlet and outlet sides. Flanges are provided on the inner surfaces of the bellows flared edges on both the medium inlet and outlet sides. The guide tube flared edge, bellows flared edge, and flange on the medium inlet side are fixedly connected by screw assembly a. The bellows flared edge and flange on the medium outlet side are fixedly connected by screw assembly b.

[0008] According to one embodiment of the present invention, the screw assembly a includes a hexagonal nut a and a countersunk screw a. The countersunk screw a is used to pass through the flange ring, bellows flange, guide tube flange and external pipe on the medium inlet side. The hexagonal nut a and the countersunk screw a are threadedly connected for locking and fixing.

[0009] According to one embodiment of the present invention, the screw assembly b includes a hexagonal nut b and a countersunk screw b. The countersunk screw b is used to pass through the flange ring, bellows flange and external pipe on the medium outlet side. The hexagonal nut b and the countersunk screw b are threaded together for locking and fixing.

[0010] According to one embodiment of the present invention, it further includes at least one transport component, which includes a lug a, a lug b, a transport rod, and two pairs of hexagonal nuts c. The lug a and lug b are respectively fixed on the side walls of two flange rings on both sides of the medium inlet and outlet. The transport rod passes through the lug a and lug b in sequence to assist the operator in lifting the expansion joint. The two pairs of hexagonal nuts c are respectively provided on the transport rod at lug a and lug b to lock and fix the transport rod to lug a and lug b.

[0011] According to one embodiment of the present invention, the guide tube is made of PTEE material.

[0012] The advantages of this utility model compared with the existing technical solutions are:

[0013] 1. This utility model has a PTEE layer fixedly provided on the inner wall of the bellows. When bromide ions come into contact with the bellows, they first come into contact with the corrosion-resistant PTEE layer, thereby effectively reducing the risk of the bellows being corroded by bromide ions and significantly extending the service life of the expansion joint.

[0014] 2. This utility model involves fitting a corrugated pipe around the outside of the guide tube along the direction of medium inflow and outflow, so that the corrosive medium flows out of the expansion joint along the direction of the guide tube, thereby reducing the chance of the corrosive medium contacting the corrugated pipe and extending the service life of the expansion joint.

[0015] 3. This utility model uses screw assembly a and screw assembly b to fix and connect the bellows, guide tube and flange ring, effectively preventing these three parts from falling off and ensuring safety in use.

[0016] 4. This utility model also includes at least one transport component, which allows the operator to lift the expansion joint simply by lifting the transport lever, thus facilitating the operator's handling and installation.

[0017] 5. The guide tube in this utility model is made of PTEE material, which helps to further improve the overall service life of the expansion joint. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] In the diagram: 1. Bellows; 2. Bellows flange; 3. Flow guide; 4. Flow guide flange; 5. Flange ring; 6. Hex nut a; 7. Countersunk screw a; 8. Hex nut b; 9. Countersunk screw b; 10. Ear plate a; 11. Ear plate b; 12. Transport tie rod; 13. Hex nut c. Detailed Implementation

[0020] The present invention will now be described in detail through specific embodiments, but this does not limit the scope of protection of the present invention.

[0021] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", 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 the present 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 limitations on this utility model.

[0022] Unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] Example 1

[0024] like Figure 1 As shown, this embodiment provides a novel expansion joint for the inlet and outlet of the carrier gas fan in a PTA unit oxidation dryer, including a bellows 1, a bellows flange 2, a guide tube 3, a guide tube flange 4, a flange ring 5, a hexagonal nut a6, a countersunk screw a7, a hexagonal nut b8, and a countersunk screw b9. The bellows 1 is used to absorb axial, lateral, and angular displacements at the inlet and outlet of the carrier gas fan caused by factors such as temperature changes, medium flow, or mechanical vibration, thereby ensuring the stability and safety of the carrier gas fan.

[0025] The bellows 1 adopts a double-layer structure design. The outer layer is made of corrosion-resistant 316L stainless steel, while the inner wall is made of PTEE (polytetrafluoroethylene). PTEE has excellent chemical resistance and can resist the corrosion of various chemicals, including strong acids, strong alkalis, and organic solvents. Especially at the inlet and outlet of the carrier gas blower in the PTA unit's oxidation dryer, the use of PTEE material can greatly extend the service life of the bellows 1. Both the medium inlet and outlet sides of the bellows 1 are provided with outward-flaring bellows flanges 2. The bellows flanges 2 are used to cooperate with screw assemblies a and b to connect and fix the bellows 1, the guide tube 3, and the flange ring 5 to the external pipeline.

[0026] The bellows 1 is fitted onto the outside of the guide tube 3 along the medium inlet / outlet direction, and the axial length of the guide tube 3 is less than the axial length of the bellows 1. The guide tube 3 is used to allow the corrosive medium to flow out of the expansion joint along the direction of the guide tube 3, thereby reducing the probability of the corrosive medium contacting the bellows 1 and extending the service life of the expansion joint. An outwardly flared guide tube flange 4 is provided at the edge of the medium inlet side of the guide tube 3. Providing the guide tube flange 4 on only one side ensures that the guide tube 3 does not affect the displacement absorption of the bellows 1, and effectively guides the corrosive medium to flow out of the expansion joint along the direction of the guide tube. The guide tube flange 4 is used to cooperate with the screw assembly a to connect and fix the bellows 1, guide tube 3, flange ring 5 to the external pipeline.

[0027] Screw assembly a includes a hexagonal nut a6 and a countersunk screw a7, and screw assembly b includes a hexagonal nut b8 and a countersunk screw b9. Flanges 5 are provided on the inner surfaces of the bellows flange 2 on both the medium inlet and outlet sides. The countersunk screw a7 is used to pass through and connect the flange 5, bellows flange 2, guide tube flange 4, and external pipe on the medium inlet side. The hexagonal nut a6 is threaded to the countersunk screw a7 for locking and fixing. The countersunk screw b9 is used to pass through and connect the flange 5, bellows flange 2, and external pipe on the medium outlet side. The hexagonal nut b8 is threaded to the countersunk screw b9 for locking and fixing.

[0028] Since the bellows 1 is susceptible to corrosion during the process of the medium passing through the expansion joint, the guide tube 3 is also susceptible to corrosion. Therefore, the material of the guide tube 3 is PTEE, which can greatly improve the service life of the expansion joint.

[0029] Example 2

[0030] This embodiment adds a transportation component compared to Embodiment 1; the rest of this embodiment is the same as Embodiment 1.

[0031] like Figure 1 As shown, the transport assembly includes ear plate a10, ear plate b11, transport rod 12, and two pairs of hexagonal nuts c13. Ear plates a10 and b11 are fixed to the side walls of two flange rings 5 ​​on both sides of the medium inlet and outlet, respectively. The flange rings 5 ​​are used to assist screw assemblies a and b in connecting the transport assembly to the bellows 1. The transport rod 12 passes through ear plates a10 and b11 sequentially. When the expansion joint needs to be moved, the operator only needs to lift the transport rod 12. There are four hexagonal nuts c13, located on the transport rod 12 on the left, right, left, and right sides of ear plates a10 and b11, respectively. The hexagonal nuts c13 are used to lock and fix the transport rod 12 to ear plates a10 and b11.

[0032] The embodiments described above are merely preferred embodiments of this utility model, and not all feasible embodiments of this utility model. For those skilled in the art, any obvious modifications made without departing from the principles and spirit of this utility model should be considered to be included within the scope of protection of the claims of this utility model.

Claims

1. A novel expansion joint for the inlet and outlet of the carrier gas fan in a PTA unit oxidation dryer, characterized in that, The device includes a bellows (1), a guide tube (3), and a screw assembly a. The guide tube (3) is hollow inside and used to flow the drying medium. The bellows (1) is sleeved on the outside of the guide tube (3) along the medium inlet and outlet direction. A PTEE layer is fixedly provided on the inner wall of the bellows (1). The guide tube flange (4) is provided on the edge of the medium inlet side of the guide tube (3). The bellows flange (2) is provided on the edge of both the medium inlet side and the medium outlet side of the bellows (1). The inner side of the bellows flange (2) on both the medium inlet side and the medium outlet side is provided with a flange ring (5). The guide tube flange (4), the bellows flange (2), and the flange ring (5) on the medium inlet side are fixedly connected by the screw assembly a. The bellows flange (2) and the flange ring (5) on the medium outlet side are fixedly connected by the screw assembly b.

2. The inlet and outlet expansion joint of the carrier gas fan in the oxidation dryer of a novel PTA unit according to claim 1, characterized in that, The screw assembly a includes a hexagonal nut a (6) and a countersunk screw a (7). The countersunk screw a (7) is used to pass through the flange ring (5), bellows flange (2), guide tube flange (4) and external pipe on the inlet side of the connecting medium. The hexagonal nut a (6) is threaded to the countersunk screw a (7) for locking and fixing.

3. The inlet and outlet expansion joint of the carrier gas fan in the oxidation dryer of a novel PTA unit according to claim 2, characterized in that, The screw assembly b includes a hex nut b (8) and a countersunk screw b (9). The countersunk screw b (9) is used to pass through the flange ring (5), bellows flange (2) and external pipe on the outlet side of the connecting medium. The hex nut b (8) is threaded to the countersunk screw b (9) for locking and fixing.

4. The inlet and outlet expansion joint of the carrier gas fan in the oxidation dryer of a novel PTA unit according to claim 1, characterized in that, It also includes at least one transport component, which includes ear plate a (10), ear plate b (11), transport rod (12), and two pairs of hexagonal nuts c (13). Ear plate a (10) and ear plate b (11) are respectively fixed on the side wall of two flange rings (5) on both sides of the medium inlet and outlet. The transport rod (12) passes through ear plate a (10) and ear plate b (11) in sequence to assist the operator in lifting the expansion joint. The two pairs of hexagonal nuts c (13) are respectively located on the transport rod (12) at ear plate a (10) and ear plate b (11) to lock and fix the transport rod (12) to ear plate a (10) and ear plate b (11).

5. The inlet and outlet expansion joint of the carrier gas fan of the oxidation dryer in a novel PTA unit according to any one of claims 1-4, characterized in that, The guide tube (3) is made of PTEE material.

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