A series of pipe reactors with flexible jacket closing

Abstract

The present invention relates to the technical field of serial tube reactors, and specifically to a serial tube reactor with a flexible closing of a jacket, comprising a straight sleeve, a jacket connecting pipe, an elbow and a mounting support, wherein the straight sleeve comprises an inner tube and an outer tube, the elbow and the inner tube are sequentially connected in series to form a medium flow channel for conveying reaction materials and reacting, the jacket connecting pipe near the end of the jacket connects the jacket flow channel formed between the inner tube and the outer tube in series to form a cooling flow channel for conveying cooling medium, the mounting support is arranged at the lower part of the outer tube to divide the straight sleeve into an upper pipe section of the straight sleeve and a lower pipe section of the straight sleeve, and the closed connection of the inner tube and the outer tube at both ends of the straight sleeve is a flexible closing structure. Compared with the prior art, the flexible closing structure of the jacket has the functions of absorbing thermal expansion and contraction displacement, buffering lifting bending displacement, reducing the stress of the pipe section expansion joint, and optimizing the overall utility of the equipment; it provides conditions for reducing the outer dimensions of the lower pipe section expansion joint and even the mounting support, optimizing the equipment installation foundation, and reducing engineering investment.

Description

Technical Field

[0001] The invention relates to the technical field of serial tube reactors, and in particular to a serial tube reactor with a flexible jacket closing. Background Art

[0002] Polypropylene and polyethylene are the most produced and consumed types of general synthetic resins. There are three production technologies for them, namely slurry polymerization, gas phase polymerization and solution polymerization. Slurry process is the main method, which can be divided into stirred tank reactor and series pipe reactor according to the reactor form. The series pipe reactor is also called loop reactor.

[0003] The traditional series pipe reactor is composed of several straight sleeves, jacket connecting pipes, elbows, mounting supports and connecting beams, etc., depending on the capacity. Every two straight pipe cylinders and two elbows form a cycle. Because the polymerization reaction will generate heat, the reaction heat is taken away by the cooling water in the jacket. The outer pipe of the straight sleeve is provided with a corrugated expansion joint, mounting support and support beam seat. There is no sleeve on the elbow. The elbow is connected to the inner pipe of the straight sleeve through a flange to connect the straight sleeves into a whole process. The jacket connecting pipe connects the jacket of the straight sleeve into a whole process. The connecting beam is connected to the support beam seat through bolts to combine the straight sleeves into a three-dimensional frame. The string pipe reactor is supported by multiple foundations, that is, each straight sleeve has its own installation support. The errors in the length, axis position, orientation, elevation, spacing, etc. of the straight sleeve, as well as the parallelism of the straight sleeve, the verticality of the flange, the manufacturing error of the elbow and many other factors will affect the sealing performance of the annular pipe installation at the same time. The installation of the string pipe reactor can be divided into two types: upright and inclined. The latter occupies a slightly larger area and its overall structure is more stable than the former.

[0004] For example Figure 1As shown, the vertically installed series tube reactor is mainly composed of six straight sleeves (R1-R6), five 180° large elbows (A1, A2, A3, B1, B2), and a 90° elbow connected in sequence to form a circulation whole, and is located on a higher platform foundation through five jacket connecting pipes C1, C2, C3, C4, and C5 connected to the outer pipe at the elbow. An axial flow pump is provided at the elbow at the bottom of the ring pipe. The reaction material enters the series tube reactor from the reaction material inlet 1A, is stirred and circulated in the pipe under the drive of the axial flow pump, reacts to form slurry polypropylene under the action of the catalyst, and is discharged from the reaction material outlet 1B into the granulation system; the cooling medium enters from the cooling medium inlet 2A of the jacket flow channel and flows out to the cooling medium outlet 2F of the jacket flow channel. Six mounting supports D1, D2, D3, D4, D5, and D6 are located at the lower part of each straight sleeve R1, R2, R3, R4, R5, and R6. The jackets are connected to each other by five jacket connecting pipes. The cooling water in the jacket takes away the heat released by the reaction in the inner tube through the partition wall to maintain the normal operation of the reaction process. In order to coordinate the difference in thermal expansion displacement caused by the different temperatures of the inner and outer tubes, expansion joints are attached to the jackets. Support beam seats and supports are also attached to the jackets. Adjacent jackets are connected by steel sections to form several space platforms.

[0005] Basic structural issues

[0006] With the scarcity of oil resources, in order to adapt to the huge market demand and development of ethylene special materials, new and more stringent requirements have been put forward for the structure, production capacity and quality of string tube reactor equipment. Chemical companies hope to reduce costs and improve the market competitiveness of prices through the scale effect of high production capacity. In 1996, the production capacity of a single string tube reactor for the first time in China was 70,000 tons / year. In 2009, the production capacity of the first domestic solution polymerization polypropylene circulation reactor reached 450,000 tons / year, which posed a challenge to the traditional slurry polymerization string tube reactor. At present, the string tube reactor urgently needs to gradually increase its production capacity from 300,000 tons / year to 350,000 tons / year, 400,000 tons / year and 450,000 tons / year or more.

[0007] As the production capacity scale is further expanded, the above-mentioned conventional serial pipe reactor, because the straight sleeve adopts an integrated slender vertical structure, when the length of the straight sleeve exceeds 60 meters or even reaches 70 meters, many problems will arise. Here are only the following shortcomings:

[0008] First, the difference in thermal expansion and contraction displacement between the inner and outer tubes of the serial tube reactor increases, and the number of corrugations of the expansion joint on the jacket increases to more than 6. The design, manufacture and quality assurance of multi-wave expansion joints become new challenges, and their manufacturing accuracy is getting lower and lower.

[0009] Secondly, the traditional corrugated expansion joint structure cannot achieve the best effect when absorbing and buffering the difference, and the number of waves required is increasing, which is not conducive to the stability of the tall structure, and its operation function is becoming increasingly difficult to guarantee;

[0010] Third, in the process of loading, unloading, transferring and assembling the extra-long straight casing, it is more difficult to keep the entire straight casing in a straight state. The inventors found that the bending displacement in the middle of the straight casing is often the largest, which causes great damage to the expansion joints arranged therein, while the bending displacement at both ends of the straight casing jacket is generally the smallest, which is more suitable for setting a flexible structure.

[0011] Fourthly, the earliest jacket closing structures are traditionally rigid ring structures. During stress analysis and design verification, these structures are often high-level stress concentration points caused by various loads including thermal displacement differences, making it difficult to pass safety assessments.

[0012] Fifth, for the jacket structure, the difference in thermal expansion displacement between the inner and outer tubes and the origin of the thermal stress caused by them is the joint between the two. When the rigid ring joint structure cannot be designed, an expansion joint is added to the jacket. As the straight sleeve jacket gradually grows, the expansion joints that need to be set in the jacket also develop from one waveform, two waveforms to five waveforms and six waveforms. This is a technical means of conventional mechanical thinking of those skilled in the art.

[0013] Sixth, as the number of expansion joint waveforms in the jacket increases, the contribution of each wave in the operation of the multi-wave expansion joint is different. The waveforms at both ends contribute more, while the waveform in the middle contributes less, or the waveform at one end contributes more, while the waveform at the other end contributes less. As a result, one waveform fails quickly while the other waveforms are still intact.

[0014] Seventh, traditional structural design positions the expansion joint that deals with this problem in the middle of the casing length away from the closing end, far from the origin of displacement difference and thermal stress. It is believed that as long as the expansion joint is set up, it will definitely work 100%. In fact, there are difficulties in transmitting the expected effect, transmission failure or hysteresis effect, which is not conducive to the expansion joint to play its role in a timely and effective manner. This is a reflection of idealized thinking without any practical experience.

[0015] In summary, in order to quickly adapt to the current market environment of large demand for high-capacity and large-structure string tube reactors in the new construction and expansion of petrochemical industry, to meet the needs of capacity expansion, capacity expansion and upgrading of traditional string tube reactors, and high-capacity demand of polypropylene production capacity of more than 400,000 tons / year, the development of new structure high-capacity string tube reactors has far-reaching and significant industrial and economic significance. Summary of the invention

[0016] In view of the above technical problems in the prior art, the present invention provides a series tube reactor with a flexible jacket, which has a good effect of absorbing thermal expansion and contraction displacement.

[0017] To achieve the above object, the present invention provides the following technical solutions:

[0018] Provided is a series tube reactor with a jacketed flexible closing, comprising a straight sleeve, a jacketed connecting pipe, an elbow and a mounting support, wherein the straight sleeve comprises an inner tube and an outer tube, the elbow and the inner tube are sequentially connected in series to form a medium flow channel for conveying reaction materials and reacting, the jacketed connecting pipe is located at the elbow and connected to the outer tube, and the jacket flow channel formed between the inner tube and the outer tube is connected in series to form a cooling flow channel for conveying cooling medium, the mounting support is arranged on the outer side of the outer tube to divide the straight sleeve into a straight sleeve upper tube section and a straight sleeve lower tube section, and is characterized in that: the closed connection position between the inner tube and the outer tube at the end of the straight sleeve is a flexible closing structure that can be elastically deformed by heat.

[0019] Optionally, the closed connection positions of the inner tube and the outer tube of all the straight sleeves of the series tube reactor are provided with flexible closing structures.

[0020] Optionally, only the closed connection position between the inner tube and the outer tube of a portion of the straight tubes of the series tube reactor is provided with a flexible closing structure.

[0021] Optionally, ends of the upper pipe section of the straight casing and the lower pipe section of the straight casing are both provided with a flexible closing structure at a closed connection position between the inner pipe and the outer pipe.

[0022] Optionally, only one of the straight casing upper pipe section and the straight casing lower pipe section has a flexible closing structure at the end portion at the closed connection position between the inner pipe and the outer pipe.

[0023] Optionally, the flexible closing structure includes a thin-walled annular plate and a corrugated closing section, the thin-walled annular plate is vertically welded to the outer wall of the inner tube, one end of the corrugated closing section is welded to the end of the outer tube, and the other end of the corrugated closing section is welded to the thin-walled annular plate.

[0024] Optionally, the flexible closing structure includes a thin-walled arc plate and a corrugated closing section, one end of the thin-walled arc plate is welded to the outer wall of the inner tube and arched away from the inner tube, one end of the corrugated closing section is welded to the end of the outer tube, and the other end of the corrugated closing section is welded to the other end of the thin-walled arc plate.

[0025] Optionally, the flexible closing structure includes a corrugated closing section, one end of the corrugated closing section is welded to the end of the outer tube, and the other end of the corrugated closing section radially extends and is welded to the outer wall of the inner tube.

[0026] Optionally, an extended lap edge is provided at the end of the corrugated closing section, and the extended lap edge and the outer wall of the inner tube are welded to each other.

[0027] Optionally, the flexible closing structure is a thin-walled annular arc plate, one end of which is welded to the outer wall of the inner tube and arched away from the inner tube, and the other end of the thin-walled annular arc plate is welded and fixed to the end of the outer tube.

[0028] Optionally, the flexible closing structure is a single-layer structure, a multi-layer structure or a variable thickness structure.

[0029] Optionally, the flexible closing structure is a structure of the same material or a structure of different materials.

[0030] Optionally, the flexible closing structure is in the shape of a cone, a corrugated shape, a ring shell shape or a ring flat plate shape.

[0031] Optionally, the flexible closing structure at the end of the straight sleeve jacket includes an overall flexible structure and a local flexible structure.

[0032] Beneficial effects of the present invention:

[0033] The serial pipe reactor with flexible closing of the jacket of the present invention is provided with a flexible closing structure at the end of the straight sleeve, replacing the original thick-walled rigid ring jacket closing structure, so that the two functions of the newly provided flexible closing structure at the end of the jacket and the traditional expansion joint provided in the middle of the straight sleeve section are combined into one, replacing the original two old structures, and the overall structure is simplified. Compared with the prior art, it not only has the triple effects of jacket closing function, absorbing thermal expansion and contraction displacement, and buffering lifting bending displacement, but also because of the provision of a flexible closing structure, the traditional lower pipe section expansion joint can be reduced or even eliminated, so that the fourth effect of engineering device optimization can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of a series tube reactor in the prior art.

[0035] Figure 2 It is a structural schematic diagram of Example 1 of a series tube reactor with a flexible jacket closing according to the present invention.

[0036] Figure 3 It is a structural schematic diagram of Example 2 of a series tube reactor with a flexible jacket closing according to the present invention.

[0037] Figure 4 It is a structural schematic diagram of Example 3 of a series tube reactor with a flexible jacket closing according to the present invention.

[0038] Figure 5 It is a structural schematic diagram of Example 4 of a series tube reactor with a flexible jacket closing according to the present invention.

[0039] Figure 6 It is a structural schematic diagram of Example 5 of a series tube reactor with a flexible jacket closing according to the present invention.

[0040] Figure 7 It is a structural schematic diagram of Example 6 of a series tube reactor with a flexible jacket closing according to the present invention.

[0041] Figure 8 It is a structural schematic diagram of Example 7 of a series tube reactor with a flexible jacket closing according to the present invention.

[0042] Fig. 9 It is a structural schematic diagram of Example 8 of a series tube reactor with a flexible jacket closing according to the present invention.

[0043] Reference numerals:

[0044] exist Figure 1 Included are:

[0045] R1, R2, R3, R4, R5, R6 - straight casing;

[0046] A1, A2, A3, B1, B2, B3 - elbows;

[0047] C1, C2, C3, C4, C5——jacket connecting pipes;

[0048] D1, D2, D3, D4, D5, D6 - installation support;

[0049] 2A——Cooling medium inlet of jacket flow channel; 2F——Cooling medium outlet of jacket flow channel;

[0050] 1A——reaction material inlet; 1B——reaction material outlet.

[0051] exist Figures 2 to 9 Included are:

[0052] 101——outer tube, 102——inner tube;

[0053] 11——upper section of straight casing, 12——lower section of straight casing;

[0054] 21——Multi-wave expansion joint of the upper pipe section, 22——Expansion joint of the lower pipe section;

[0055] 30——Installation support;

[0056] 31——Flexible closing structure of the upper pipe section;

[0057] 301——corrugated closing section;

[0058] 41——Flexible closing structure of the lower pipe section;

[0059] 501——Thin-walled ring plate;

[0060] 502——thin-walled arc plate;

[0061] 51 – girth weld;

[0062] 61——Installation platform of serial pipe reactor;

[0063] 62 – Support pillars for mounting platforms;

[0064] H——The lower pipe section of the series tube reactor is inserted into the mounting hole of the mounting platform. DETAILED DESCRIPTION

[0065] The present invention is described in detail below in conjunction with specific embodiments and drawings.

[0066] Example 1

[0067] One of the specific embodiments of the series pipe reactor with flexible jacket closing of the present invention is as follows: Figure 2 and Fig. 9 As shown, it includes a straight sleeve, a jacket connecting pipe, an elbow and a mounting support 30, the straight sleeve includes an outer tube 101 and an inner tube 102, the elbow and the inner tube 102 are sequentially connected in series to form a medium flow channel for transporting and reacting reaction materials, the jacket connecting pipe is located at the elbow and connected to the outer tube 101, and the jacket flow channel formed between the inner tube 102 and the outer tube 101 is connected in series to form a cooling flow channel for transporting cooling medium, the mounting support 30 is arranged on the outer wall of the outer tube 101 to divide the straight sleeve into a straight sleeve upper pipe section 11 and a straight sleeve lower pipe section 12, and the above technical features are the same as the structure of the series pipe reactor in the prior art. The straight sleeve upper pipe section 11 is provided with a multi-wave expansion joint 21, and the straight sleeve lower pipe section 12 is provided with an expansion joint 22 (in order to reflect the difference between the front and the back, the drawings of this embodiment still show the expansion joint). The main innovation of the present invention is that the closed connection position between the inner tube 102 and the outer tube 101 at the end of the straight sleeve is a flexible closing structure 31 and 41 that can be elastically deformed by heat.

[0068] The present invention provides a flexible closing structure at the end of the straight sleeve to replace the original thick-walled rigid ring jacket closing structure, so that the two functions of the newly arranged flexible closing structure at the jacket end and the traditional expansion joint arranged in the middle part of the straight sleeve section are combined into one, replacing the original two old structures, and the overall structure is simplified.

[0069] Compared with the prior art, the flexible closing structure not only has the triple effects of jacket closing function, absorbing thermal expansion and contraction displacement, and buffering lifting bending displacement, but also can reduce the traditional lower pipe expansion joint or even eliminate the lower pipe expansion joint due to the flexible closing structure, thus achieving the fourth effect of engineering device optimization. Specifically, it reduces the installation foundation hole H, the installation platform 61, the platform support 62 and other related structures, reduces the external dimensions of the installation support 30, and optimizes the overall utility of the equipment, such as Fig. 9 As shown; it also provides conditions for optimizing the equipment installation foundation and reducing engineering investment, because the installation platform 61, platform pillars 62 and other related structures are constructed of reinforced cement stone concrete. The larger the opening H, the more the platform structure is weakened, and special reinforcement is required to support the huge tonnage and withstand the strong hurricane load. For a long time, this has also been a technical difficulty and a hard bone in the civil engineering profession in the construction of polyolefin plants. If the multi-wave expansion joints in the lower pipe section can be reduced or even eliminated, it will not only be a significant equipment technology advancement, but also because it enables the cross-border and related civil engineering profession to optimize the reactor support foundation structure, which is a technical advancement of the entire engineering plant.

[0070] Comparisons in other aspects include: the original thick-walled rigid ring jacket closing structure is difficult to pass the stress analysis design verification, because the thick-walled rigid ring jacket closing structure has a serious disadvantage, that is, in comparison, the inner tube 102 and the outer tube 101 welded thereto have become thin-walled weak structures (thickness is relative). Under the action of various complex load stresses, the thin-walled weak structure, especially the inner tube 102, is deformed, destroying the stability of the medium flow state, increasing the friction between the medium and the inner wall to accelerate erosion and corrosion, and also affecting the flange seal at the side end; even if the wall thickness of the connector is increased and passed, the welding groove structure design between the rigid ring and the inner and outer sleeves is difficult, and the penetration groove welding volume is large, which causes welding deformation of the thin-walled weak structure of the inner and outer tubes 101, and the thick weld is not convenient for non-destructive testing of the weld quality; the change in the wall thickness of the structural parts makes the material specifications and types diversified, and the materials with special sizes and small quantities cause procurement difficulties and cost increases, which is not conducive to engineering construction. For example, the prior art has patent number ZL201220468579 and its name is “A series pipe reactor with a jacketed expansion joint”.

[0071] In comparison, the flexible closing structure of the present invention can solve all the above problems:

[0072] First of all, the activeness of its efficacy. The flexible closing structure is thin-walled (compared with the inner tube 102 and the outer tube 101). In contrast, the inner tube 102 and the outer tube 101 welded thereto are both thick-walled and strong structures. Under various loads, the thin-walled flexible closing structure is easily deformed, absorbing and dissolving complex stresses, and protecting the inner tube 102 and the outer tube 101.

[0073] Secondly, the timeliness of its effect. The flexible closing structure is located at a key position, which is the origin of displacement difference and thermal stress. The generated displacement difference and thermal stress problems are solved synchronously in the local structure, without difficulty, failure or lag in effect transmission, and can play a role in a timely and effective manner.

[0074] The third is the durability of its effect. When (one or more layers) of thin steel plates are used to manufacture the closing structure, the quality of thin steel plates is inherently more guaranteed than that of thick steel plates. During the structural forming process, thin steel plates have low deformation resistance and are very convenient to form. The manufacturing energy consumption is low, and the structural shape and size accuracy is easy to guarantee. The excellent nature of the flexible closing structure lays the foundation for its long-term performance.

[0075] Fourth, the reliability of its assembly welding. Thin-walled structures are easy to weld through, and it is also suitable for flexible use of various welding methods such as manual arc welding, argon arc welding, submerged arc automatic welding, etc., to improve work efficiency;

[0076] The fifth is the operability of its detection. It is easy to achieve satisfactory results by applying various detection methods to detect thin-walled welds, especially because they are easily penetrated by rays, RT detection can also be used.

[0077] These are incomparable to the original thick-walled rigid ring jacket closing structure. The technical principle of the flexible closing structure is to go from the traditional extreme to the other extreme in the opposite direction, which is a significant innovation in the direction of the technical path.

[0078] In practice, the closed connection positions between the inner tube 102 and the outer tube 101 of all the straight tubes in the series of tubes reactor are provided with a flexible closing structure; or only the closed connection positions between the inner tube 102 and the outer tube 101 of some of the straight tubes in the series of tubes reactor are provided with a flexible closing structure.

[0079] In practical applications, the ends of the straight casing upper pipe section 11 and the straight casing lower pipe section 12 are both provided with a flexible closing structure at the closed connection position between the inner pipe 102 and the outer pipe 101; or only one of the straight casing upper pipe section 11 and the straight casing lower pipe section 12 is provided with a flexible closing structure at the closed connection position between the inner pipe 102 and the outer pipe 101.

[0080] In practical applications, the flexible closing structure is a single-layer structure, a multi-layer structure or a variable thickness structure. While the outer diameter is gradually reduced to achieve the closing, the wall thickness of the structure is appropriately gradually increased to form an optimized structure so that each part of the entire ring shell shape evenly shares the thermal expansion displacement stress of the jacket.

[0081] In practical applications, the flexible closing structure is made of the same material or a different material than the inner tube 102 or the outer tube 101. The inner layer with anti-corrosion function and the outer layer with excellent elasticity are combined.

[0082] Optionally, the flexible closing structure at the end of the straight sleeve jacket includes an overall flexible structure or a local flexible structure.

[0083] Optionally, the flexible closing structure is in the shape of a cone, a corrugated shape, a ring shell shape or a ring flat plate shape.

[0084] Example 2

[0085] A second specific embodiment of a series of pipe reactors with flexible jacket closing of the present invention is as follows: Figure 3 As shown, the main technical scheme of this embodiment is the same as that of embodiment 1. For features not explained in this embodiment, the explanation in embodiment 1 is adopted and no further description is given here. The difference between this embodiment and embodiment 1 is that the flexible closing structure includes a thin-walled annular plate 501 and a corrugated closing section 301, the thin-walled annular plate 501 is vertically welded to the outer wall of the inner tube 102, one end of the corrugated closing section 301 is welded to the end of the outer tube 101 through a grommet 51, and the other end of the corrugated closing section 301 is welded to the thin-walled annular plate 501 through a grommet 51.

[0086] Example 3

[0087] A third specific embodiment of a series of pipe reactors with flexible jacket closing of the present invention is as follows: Figure 4 As shown, the main technical scheme of this embodiment is the same as that of embodiment 1. For features not explained in this embodiment, the explanation in embodiment 1 is adopted and will not be repeated here. The difference between this embodiment and embodiment 1 is that the flexible closing structure includes a thin-walled annular arc plate 502 and a corrugated closing section 301. One end of the thin-walled annular arc plate 502 is welded to the outer wall of the inner tube 102 through an annular weld 51 and arches in the direction away from the inner tube 102. One end of the corrugated closing section 301 is welded to the end of the outer tube 101 through an annular weld 51, and the other end of the corrugated closing section 301 is welded to the other end of the thin-walled annular arc plate 502 through an annular weld 51. The multiple corrugations of the corrugated closing section 301 are also welded and formed by annular welds 51.

[0088] Example 4

[0089] A fourth specific implementation of a series of pipe reactors with flexible jacket closing of the present invention is as follows: Figure 5 As shown, the main technical scheme of this embodiment is the same as that of embodiment 1. For features not explained in this embodiment, the explanation in embodiment 1 is adopted and will not be repeated here. The difference between this embodiment and embodiment 1 is that the flexible closing structure only includes a corrugated closing section 301, one end of the corrugated closing section 301 is welded to the end of the outer tube 101 through a ring weld 51, and the other end of the corrugated closing section 301 radially extends through the ring weld 51 and is welded to the outer wall of the inner tube 102. Further, as Figure 6 As shown, an extended lap edge is provided at the end of the corrugated closing section 301 , and the extended lap edge and the outer wall of the inner tube 102 are welded to each other through a circumferential weld 51 .

[0090] For the flexible closing structure of the corrugated closing section, Figure 6 In addition to the two waveforms having equal outer diameters as shown, the outer diameters of the two or more waveforms may be unequal and gradually reduced to form a double flexible structure with a closed end. The double flexibility is the superposition of waveform flexibility and diameter reduction flexibility.

[0091] For the flexible closing structure of the corrugated closing section, Figure 6 In addition to the two structures shown in which the outer diameter of the waveform is larger than the outer diameter of the outer tube 101 of the straight sleeve, there is also a structure in which the outer diameter of the waveform is equal to or smaller than the outer diameter of the outer tube 101 of the straight sleeve. Because this is a closing structure located at the end, it is feasible that the outer diameter of the waveform is smaller than the outer diameter of the outer tube 101 of the straight sleeve.

[0092] Example 5

[0093] A fifth specific embodiment of a series of pipe reactors with flexible jacket closing of the present invention is as follows: Figure 7 As shown, the main technical scheme of this embodiment is the same as that of Embodiment 1. The features not explained in this embodiment are explained in Embodiment 1 and will not be described again here. The difference between this embodiment and Embodiment 1 is that the flexible closing structure is a thin-walled annular arc plate 502, one end of the thin-walled annular arc plate 502 is welded to the outer wall of the inner tube 102 through an annular weld 51, and is arched in the direction away from the inner tube 102, and the other end of the thin-walled annular arc plate 502 is welded and fixed to the end of the outer tube 101 through an annular weld 51. There is no corrugated closing 301, and there is no thin-walled flat plate 501. Further as Figure 8 As shown, the end of the thin-walled annular arc plate 502 extends and overlaps the outer wall of the inner tube.

[0094] For the ring shell flexible closing structure, Figure 7 and Figure 8 In addition to the structure with equal wall thickness as shown in the figure, it also includes a structure in which the outer diameter gradually decreases and the wall thickness gradually increases appropriately, so that the various parts of the entire annular shell shape can evenly share the thermal expansion displacement stress of the jacket.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A series of pipe reactors with a jacketed flexible closing, comprising a straight sleeve, a jacketed connecting pipe, an elbow and a mounting support, wherein the straight sleeve comprises an inner pipe and an outer pipe, the elbow and the inner pipe are sequentially connected in series to form a medium flow channel for transporting reaction materials and reacting, the jacketed connecting pipe is located at the elbow and connected to the outer pipe, and the jacket flow channel formed between the inner pipe and the outer pipe is connected in series to form a cooling flow channel for transporting cooling medium, the mounting support is arranged on the outer side of the outer pipe to divide the straight sleeve into a straight sleeve upper pipe section and a straight sleeve lower pipe section, characterized in that: The closed connection position between the inner tube and the outer tube at the end of the straight sleeve is a flexible closing structure that can be elastically deformed by heat; the flexible closing structure includes a corrugated closing section, and the two or more corrugated outer diameters of the corrugated closing section are not equal, and the closing is gradually reduced, thereby forming a double flexible structure of corrugated flexibility superimposed on reduced diameter flexibility.

2. A series of pipe reactors with flexible jacket closing according to claim 1, characterized in that: The closed connection positions of the inner tube and the outer tube of all the straight sleeves of the series tube reactor are all provided with flexible closing structures.

3. A series of pipe reactors with flexible jacket closing according to claim 1, characterized in that: Only the closed connection positions between the inner tube and the outer tube of a part of the straight tubes of the series tube reactor are provided with a flexible closing structure.

4. A series of pipe reactors with flexible jacket closing according to claim 1, characterized in that: The ends of the upper pipe section of the straight casing and the lower pipe section of the straight casing are both provided with flexible closing structures at the closed connection positions of the inner pipe and the outer pipe.

5. A series of pipe reactors with flexible jacket closing according to claim 1, characterized in that: Only one of the straight casing upper pipe section and the straight casing lower pipe section has a flexible closing structure at the end portion at the closed connection position between the inner pipe and the outer pipe.

6. A series of pipe reactors with flexible jacket closing according to claim 1, characterized in that: The flexible closing structure includes a thin-walled annular plate and a corrugated closing section. The thin-walled annular plate is vertically welded to the outer wall of the inner tube, one end of the corrugated closing section is welded to the end of the outer tube, and the other end of the corrugated closing section is welded to the thin-walled annular plate.

7. A series of pipe reactors with flexible jacket closing according to claim 1, characterized in that: The flexible closing structure includes a thin-walled annular arc plate and a corrugated closing section. One end of the thin-walled annular arc plate is welded to the outer wall of the inner tube and arches in the direction away from the inner tube. One end of the corrugated closing section is welded to the end of the outer tube, and the other end of the corrugated closing section is welded to the other end of the thin-walled annular arc plate.

8. The serial pipe reactor with flexible jacket closing according to claim 1, characterized in that: The flexible closing structure comprises a corrugated closing section, one end of which is welded to the end of the outer tube, and the other end of which is radially extended and welded to the outer wall of the inner tube.

9. A series of pipe reactors with flexible jacket closing according to claim 8, characterized in that: An extended lap edge is provided at the end of the corrugated closing section, and the extended lap edge and the outer wall of the inner pipe are fitted and welded to each other.

10. The serial pipe reactor with flexible jacket closing according to claim 1, characterized in that: The flexible closing structure is a thin-walled annular arc plate, one end of which is welded to the outer wall of the inner tube and arched away from the inner tube, and the other end of the thin-walled annular arc plate is welded and fixed to the end of the outer tube.

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