A tube sheet with an arched transverse arc plate and an industrial furnace having the tube sheet

Abstract

The present invention relates to the technical field of petrochemical industrial furnaces, and specifically to a tube sheet with arched transverse arc plates and an industrial furnace having the tube sheet, comprising vertical panels, transverse arc plates, frame plates, and support legs. The vertical panels are provided with a plurality of support holes for the peripheral furnace tubes to pass through, and the side walls of each vertical panel are provided with a plurality of transverse arc plates. The transverse arc plates are arranged transversely and are curved in a longitudinally arched shape, with the support holes on the transverse arc plates and the vertical panels staggered. The frame plates surround the vertical panels, and the support legs are fixed to the outside of the frame plates. The longitudinally arched tube sheet has a more reasonable stress-bearing condition. On the one hand, the transverse arc plates can transfer the load borne on the arch to the two ends of the arch, distributing it to the frame plates at both ends, and more directly to the support legs at both ends, thereby reducing the stress on the middle portion of the vertical panels. On the other hand, the transverse arc plates can withstand the thrust applied to the tube sheet by friction between the tube holes and the furnace tubes when they expand and elongate due to heat, thereby compensating for the lack of stress-bearing function of the vertical panels in this direction.

Description

Technical Field

[0001] The present invention relates to the technical field of petrochemical industrial furnaces, and particularly to equipment for heat exchange of fluid media in petroleum refining, petrochemical, coal chemical and other chemical process, and specifically to a tube sheet with an arched transverse arc plate and an industrial furnace with the tube sheet. Background Art

[0002] (1) Structure design and function of traditional heating furnace

[0003] The heating furnace is the heart of oil refining and petrochemical plants. The function of the tubular heating furnace is to heat the medium (oil or gas) in the tube to the temperature required by the process.

[0004] The four sides of the furnace body are surrounded by tall furnace walls to form a furnace chamber. The furnace walls are composed of steel frames such as I-beams with steel plates welded on them. Heat preservation nails are distributed and welded on the steel plates, and heat insulation and wear-resistant materials are cast between the heat preservation nails. The supporting ears installed on both sides of the furnace walls support the tube sheet. The furnace tubes pass through the perforated tube sheet and are supported by the tube sheet. The oil to be heated flows through the furnace tubes, and high-temperature flue gas or hot air flows vertically from bottom to top (or horizontally from left to right, from right to left) outside the furnace tubes in the furnace chamber. Heat is transferred to the oil in the tubes through the tube walls.

[0005] Generally speaking, in order to fully balance and utilize various heat sources, a heating furnace usually consists of a radiation section at the bottom, a convection section above, a chimney at the top and peripheral auxiliary facilities. The convection section is composed of multiple modules with the same structure stacked up and down. In order to save the internal space of the heating furnace and reduce the overall height of the heating furnace, the convection section modules usually have a cuboid structure. The distance between the tube sheet supporting ears on both sides of the furnace walls is the span. For n tube sheets with a thickness of b, the span B is basically equal to the distance between the furnace walls. In structural design and strength checking, the industry usually simplifies the tube sheet into a simply supported beam with a constant span and thickness, an equivalent height of h, and a uniformly distributed line load of G / B. Then the tensile stress at the bottom of the tube sheet caused by the gravity of the furnace tubes and the medium inside is the largest, and it is proportional to the span B.

[0006] (2) Tube sheet of traditional heating furnace and its existing problems

[0007] With the long-term development of the social economy, on the one hand, the quality of crude oil being mined has become increasingly degraded, and oil refining and chemical process technologies have developed towards high-temperature and high-pressure deep processing. As industrial furnaces have evolved from heating functions to reaction functions, the temperatures experienced by tube sheets have become increasingly higher. On the other hand, energy demand has surged, and industrial furnaces have developed towards scale. Large-scale production capacity requires industrial furnaces to become larger and larger. Large-span furnaces require wide tube sheets to support the furnace tubes. The overall stress characteristics of wide tube sheets in the width direction are compressive stress on the upper part and tensile stress on the lower part. Tube sheets designed according to traditional structures are difficult to meet the requirements of economic construction. In 2015, the article "High-level development of large heating furnaces promotes the advancement of modular manufacturing technology [J]. Petrochemical Equipment Technology, 2015, 36(1): 28-33" reported that there are already cast tube sheets with a width of 4.6m, a height of 2.0m, and a height of 0.25m on both sides of the horizontal arc plate in China.

[0008] Therefore, improving the existing tube sheet structure can not only improve its stress mode, but also improve the casting conditions of the casting process, which can improve the economic benefits of the industrial furnace and has strong practical significance. Summary of the Invention

[0009] In view of the above technical problems in the prior art, the present invention provides a tube sheet with an arched transverse arc plate and an industrial furnace having the tube sheet.

[0010] To achieve the above objectives, the present invention provides the following technical solutions:

[0011] Provided is a tube sheet with arched transverse arc plates, comprising vertical plates, transverse arc plates, frame plates and support legs. The vertical plates are provided with a plurality of support holes for the peripheral furnace tubes to pass through. The side walls of each vertical plate are provided with a plurality of transverse arc plates, which are arranged transversely and in a longitudinally arched curved shape. The support holes on the transverse arc plates and the vertical plates are staggered. The frame plates surround the circumference of the vertical plates, and the support legs are fixed to the outer sides of the frame plates.

[0012] As a further preferred solution, the transverse arc plates are respectively provided on both sides of the vertical frame plate, or the transverse arc plate is provided on only one side of the vertical frame plate.

[0013] As a further preferred solution, the transverse arc plate is a continuous whole-section curved structure with the same curvature.

[0014] As a further preferred solution, transition arc plates are provided at the edges of the support holes of the vertical panels that intersect with the transverse arc plates, and the transverse arc plates and the transition arc plates form a continuous whole-piece structure.

[0015] As a further preferred solution, the transition arc plate is located above or below the corresponding support hole.

[0016] As a further preferred solution, the transition arc plate and the transverse arc plate are equal height structures.

[0017] As a further preferred solution, the transverse arc plate is a discontinuous segmented structure, which includes multiple arched segments.

[0018] As a further preferred solution, the curvatures of the multiple arched segments are different, and the positions of the arched centers are different.

[0019] As a further preferred solution, the vertical plate and the transverse arc plate are integrally cast together; or the vertical plate and the transverse arc plate are formed by welding steel plates.

[0020] An industrial furnace includes a furnace wall, end tube plates, support lugs, intermediate tube plates and coil tubes. The end tube plates are fixed at both ends of the furnace wall, the support lugs are fixed at the top of the furnace wall, the intermediate tube plates are distributed along the inner part of the furnace wall, the coil tubes include multiple furnace tubes and multiple elbows, the furnace tubes pass through the support holes of the intermediate tube plates and the end tube plates, and the elbows connect the multiple furnace tubes. Its characteristics are: the intermediate tube plate is a tube plate with an arched transverse arc plate as described above.

[0021] Advantages of the present invention:

[0022] For the tube plate with an arched transverse arc plate of the present invention and the industrial furnace having this tube plate, compared with the prior art, the longitudinally arched and bent tube plate has a more reasonable stress condition. On the one hand, the transverse arc plate can transfer the load borne above the arch to both ends of the arch, distribute it to the frame plates at both ends, and more directly transfer it to the supporting feet at both ends, reducing the stress on the middle part of the vertical plate. On the other hand, the transverse arc plate can bear the thrust applied to the tube plate by the friction between the furnace tubes during thermal expansion and elongation, making up for the deficiency of the vertical plate in the stress function in this direction. The present invention not only improves its stress mode but also can improve the casting conditions of the casting process, and can improve the economic benefits of the industrial furnace. Description of the drawings

[0023] Figure 1 It is a schematic structural diagram of a group of modules of the industrial furnace in the embodiment.

[0024] Figure 2 It is a schematic structural diagram of a tube plate under conventional thinking. Generally, it is thought to re-plan the flat distribution of the tube holes and set straight plates on the side walls.

[0025] Figure 3 It is the second structural form of a tube plate with a transverse arc plate in the embodiment.

[0026] Figure 4 It is the third structural form of a tube plate with a transverse arc plate in the embodiment, which is Figure 3 the A-A view schematic diagram in

[0027] Figure 5 It is the fourth structural form of a tube plate with a transverse arc plate in the embodiment, showing Figure 3 the transition arc plate structure at C.

[0028] Figure 6 This is the fifth structural form of a tube sheet with a transverse arc plate in the embodiment.

[0029] Figure 7 This is the sixth structural form of a tube sheet with a transverse arc plate in the embodiment. DETAILED DESCRIPTION

[0030] The present invention is described in detail below with reference to specific embodiments and accompanying drawings.

[0031] The industrial furnace of this embodiment, such as Figures 1 to 7 As shown, it includes a furnace wall 1, end tube sheets 3, lugs, an intermediate tube sheet 5, and a coil 2. The end tube sheets 3 are fixed to both ends of the furnace wall, the lugs are fixed to the top of the furnace wall 1, and the intermediate tube sheets 5 are distributed along the interior of the furnace wall. The coil 2 includes multiple furnace tubes 4 and multiple elbows 6. The furnace tubes 4 pass through the support holes of the intermediate tube sheet 5 and the end tube sheet 3. The elbows 6 connect the multiple furnace tubes. As an improvement:

[0032] The middle tube sheet 5 is a tube sheet with an arched transverse arc plate. It is a flat plate-frame structure with a rectangular front. Figure 3 , including vertical webs 7, transverse arc panels 9, frame panels 10 and support legs 11. The vertical webs 7 are provided with a plurality of support holes 8 for the outer furnace tubes to pass through. The side walls of each vertical web 7 are provided with a plurality of transverse arc panels 9. The transverse arc panels 9 are arranged horizontally and are in a longitudinally arched curved shape. The transverse arc panels 9 are staggered with the support holes 8 on the vertical webs 7. The frame panels 10 surround the circumference of the vertical webs 7. The support legs 11 are welded and fixed to the outside of the frame panels 10. The two ends of the transverse arc panels 9 are welded and fixed to the frame panels 10. Compared with the existing technology, the longitudinally arched intermediate tube panel 5 has a more reasonable stress condition. On the one hand, the transverse arc panels 9 can transfer the load borne on the arch to the two ends of the arch and distribute it to the frame panels 10 at both ends, and more directly transfer it to the support legs 11 at both ends, thereby reducing the stress on the middle part of the vertical webs 7. On the other hand, the transverse arc plates 9 can withstand the thrust applied to the tube sheets by friction with the tube holes when the furnace tubes expand and elongate due to heat, thus compensating for the lack of force-bearing capacity of the vertical webs 7 in this direction. This invention not only improves the force distribution pattern but also enhances the casting conditions during the casting process, thereby increasing the economic efficiency of the industrial furnace.

[0033] It should be noted that, since the existing intermediate tube plate is provided with dense support holes (tube holes), the support holes need to allow the furnace tubes to pass through without obstruction, so generally no additional plate is provided on both sides of the intermediate tube plate. If a plate is required, it is generally as follows Figure 2What comes to mind is to re-plan the layout of the support holes and set up the straight plate 51. However, the present invention breaks through this thinking. By setting the horizontally arched cross-arc plate, the force-bearing aspect is further optimized, and the service life of the tube sheet and the industrial furnace is extended. The cross-arc plate structure is a reasonable structure for supporting the pressure applied from above. Compared with the horizontal plate, it can greatly improve the load-bearing capacity of the tube sheet and extend the operation cycle of the industrial furnace.

[0034] In this embodiment, the cross-arc plates 9 are respectively provided on both sides of the vertical amplitude plate 7, or the cross-arc plate 9 is provided only on one side of the vertical amplitude plate 7. In practice, in addition to the arched cross-arc plate 9 provided on the side wall of the vertical amplitude plate 7, there may also be a straight plate coexisting. The cross-arc plates with equal heights on both sides have symmetry in structure and force-bearing. Combining Figure 4 As shown, it includes the symmetric cross-arc plates 91 symmetrically arranged on both sides of the vertical amplitude plate 7. Combining as Figure 5 As shown, the asymmetric cross-arc plates 92 on both sides, or the cross-arc plates arranged alternately on both sides can better conform to the principle of equal flow area of the molten steel flow path during the casting process of the casting tube sheet.

[0035] In this embodiment, the cross-arc plate 9 is a continuous integral bending structure with the same curvature. It enables the structure to have an effective load transfer path, as Figure 1 shown.

[0036] In this embodiment, combining Figure 6 As shown, at the hole edge of the support hole 8 where the vertical amplitude plate 7 intersects with the cross-arc plate 9, a transition arc plate 93 is provided, and the cross-arc plate 9 and the transition arc plate 93 form a continuous integral structure. The transition arc plate 93 is located above or below the corresponding support hole 8. The transition arc plate 93 and the cross-arc plate 9 are of the same height structure, enabling the structure to have an effective load transfer path.

[0037] In this embodiment, combining Figure 7 As shown, the cross-arc plate is a discontinuous segmented structure, which includes multiple arched segments. 94 and 95 are two arc plates with the same curvature but different arch centers and are connected together in the middle of the tube sheet. 94 and 9 are two arc plates with different curvatures and arch centers. It enables all tube holes to maintain the consistency of the structure. The curvatures of the multiple arched segments are different, and the positions of the arch centers are different. It enables the structure to have an effective load transfer path.

[0038] In this embodiment, the vertical amplitude plate 7 and the cross-arc plate 9 are a common integral casting structure; the integral structure is tightly connected, and the original structure of the cast steel has good high-temperature strength stability. Or the vertical amplitude plate 7 and the cross-arc plate 9 are formed by welding steel plates. The steel plate welding framework is prone to deformation. Even after adjusting and shaping to be flat, the residual internal stress in the structure will gradually be released under the high temperature of the industrial furnace and cause secondary deformation. Therefore, the steel plate welding type tube sheet is another structure when the casting conditions are not available.

[0039] In practice, it can be further improved as follows: the thickness of the lower section of the vertical plate is greater than that of the upper section. Further, the width of the horizontal plate located in the lower section of the vertical plate is greater than the width of the horizontal plate located in the upper section of the vertical plate, and this width refers to the range where the horizontal plate protrudes from the vertical plate. The width of the frame plate located in the lower section of the vertical plate is greater than the width of the frame plate located in the upper section of the vertical plate, and the width direction of the frame plate is the same as that of the horizontal plate, both referring to the protruding amplitude from the vertical plate. In this way, it fully adapts to the characteristic that the lower part of the tube sheet bears a large tensile stress in the width direction (the transverse direction perpendicular to the furnace tubes), and requires a large structural strength; while the upper part of the tube sheet bears a compressive stress in the width direction and only requires a small structural strength. On the other hand, among the several layers of furnace tubes supported by the tube holes on the tube sheet, the furnace tubes in the tube holes at the lower part of the tube sheet have a higher temperature, and the displacement of the furnace tubes due to thermal expansion and elongation is greater, and the thrust applied to the tube sheet through the friction with the tube holes is also greater. Therefore, the thicker thickness of the lower section of the vertical plate of the tube sheet can make up for the need to bear a greater thrust. The high-strength tube sheet is freely supported at both ends on the lugs inside the two-side furnace walls. The tube sheet can be equivalent to a simply supported beam, and the length of the beam is the width of the tube sheet. The beam is mainly subjected to an approximately uniform gravity, and the gravity comes from the furnace tube coils supported by the tube holes of the tube sheet and the medium inside them. The upper side of the beam is also subjected to a certain thermal expansion thrust of the furnace tubes. The high-strength tube sheet structure is a reasonable structure for supporting the pressure applied from above. Compared with the tube sheet structure with equal width up and down, it can greatly improve the load-bearing capacity of the tube sheet and extend the operation cycle of the industrial furnace.

[0040] In the description of the present invention, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", and "fixation" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0041] The standard parts used in the present invention can all be purchased from the market. The special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part all adopt conventional means such as bolts, rivets, and welding that are mature in the prior art. The machines, parts, and equipment all adopt conventional models in the prior art, and the circuit connection adopts the conventional connection method in the prior art, which will not be elaborated here.

[0042] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirits of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A tube sheet with an arched transverse arc plate, characterized in that: It includes vertical panels, transverse arc panels, frame panels and support legs. The vertical panels are provided with multiple support holes for the peripheral furnace tubes to pass through. The side walls of each vertical panel are provided with multiple transverse arc panels. The transverse arc panels are arranged horizontally and are curved in a longitudinally arched shape. The support holes on the transverse arc panels and the vertical panels are staggered. The frame panels surround the circumference of the vertical panels, and the support legs are fixed to the outer sides of the frame panels.

2. The tube sheet with an arched transverse arc plate according to claim 1, characterized in that: The transverse arc plates are respectively provided on both sides of the vertical frame plate, or the transverse arc plate is provided on only one side of the vertical frame plate.

3. A tube sheet with an arched transverse arc plate according to claim 1, characterized in that: The transverse arc plate is a continuous whole-section curved structure with the same curvature.

4. A tube sheet with an arched transverse arc plate according to claim 1, characterized in that: A transition arc plate is provided at the edge of the support hole of the vertical plate that intersects the transverse arc plate, and the transverse arc plate and the transition arc plate form a continuous whole structure.

5. The tube sheet with an arched transverse arc plate according to claim 4, characterized in that: The transition arc plate is located above or below the corresponding support hole.

6. A tube sheet with an arched transverse arc plate according to claim 4, characterized in that: The transition arc plate and the transverse arc plate are equal height structures.

7. A tube sheet with an arched transverse arc plate according to claim 1, characterized in that: The transverse arc plate is a discontinuous segmented structure, which includes multiple arched segments.

8. A tube sheet with an arched transverse arc plate according to claim 7, characterized in that: The curvatures of the multi-segment arch segments are different, and the arch center positions are different.

9. A tube sheet with an arched transverse arc plate according to claim 1, characterized in that: The vertical plate and the transverse arc plate are a common integrated casting structure; or the vertical plate and the transverse arc plate are welded together by steel plates.

10. Industrial furnace, comprising a furnace wall, end tube sheets, support lugs, intermediate tube sheets and coiled tubes, the end tube sheets are fixed at both ends of the furnace wall, the support lugs are fixed at the top of the furnace wall, the intermediate tube sheets are distributed inside the furnace wall, the coiled tubes include a plurality of furnace tubes and a plurality of elbows, the furnace tubes pass through the support holes of the intermediate tube sheets and the end tube sheets, and the elbows connect the plurality of furnace tubes. It is characterized in that: The intermediate tube sheet is a tube sheet with an arched transverse arc plate as described in any one of claims 1 to 9.

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