An apparatus and method for welding, sag testing and installation of radiant coils.

Abstract

This invention discloses an apparatus and method for welding, sag testing, and installation of radiant coils. The radiant coils are used in ethylene cracking furnaces and include straight pipes and bent pipes. The invention relates to the field of radiant coil construction technology. The apparatus includes: guide rails disposed on both sides of the top of the ethylene cracking furnace; and a trolley slidably mounted on the guide rails. The trolley has an internal receiving cavity for accommodating the straight pipes. The trolley is equipped with a lifting adjustment component and a horizontal adjustment component. The lifting adjustment component adjusts the height of the straight pipes, and the horizontal adjustment component adjusts the horizontal movement of the straight pipes. The apparatus features a trolley capable of sliding along the guide rails. The straight pipes of the radiant coils can be installed in the receiving cavity together with the positioning packaging frame without disassembling it. The entire assembly is lifted, causing the straight pipes to sag. This allows for welding of the bent pipes while suspended, facilitates sag testing, and facilitates the installation of the radiant furnace tubes.

Description

Technical Field

[0001] This invention belongs to the field of radiant coil construction technology, and more specifically, relates to an apparatus and method for radiant coil assembly welding, suspension testing and installation. Background Technology

[0002] Radiant coils are the core component of ethylene cracking furnaces. The ethylene cracking reaction is completed within the radiant coil cavity, and the radiant coils operate under high-temperature conditions. The radiant coils are located inside the radiant section of the furnace, and their upper part is connected to the quench heat exchanger. Due to the connection between the quench boiler and complex stress pipelines such as riser and downcomer pipes, they are generally not temporarily removed after initial installation.

[0003] For the welding of radiant coils in pyrolysis furnaces, welding is generally carried out in a horizontal orientation in the factory workshop, with each radiant tube section and bend welded one by one. The disadvantages of this method are: (1) The horizontal welding of each tube section is affected by gravity, and the coil is prone to lateral deformation, which affects the accuracy of coil assembly and requires high precision in furnace tube straightening and deformation control; (2) After horizontal assembly and welding, the furnace tube is dropped to a vertical position, and the welding deformation of the furnace tube is large, which affects the uniformity of heating and the distribution of heat intensity.

[0004] For the suspension test of radiant coils in a cracking furnace, the entire coil assembly is typically suspended directly to verify its suspension status. The drawback of this method is that the radiant coils are subjected to external suspension forces and are not in a free state, thus failing to achieve the precise verification purpose of the suspension test.

[0005] For the initial installation of the cracking furnace, the radiant coil is usually hoisted into the furnace from the slot in the top steel section before the quench heat exchanger is installed. The disadvantages of this method are: (1) Hoisting the radiant coil is the immediate preceding process to hoisting the quench heat exchanger, and is located on the critical path, which requires a high degree of coordination between the project procurement and installation schedule; (2) Hoisting the radiant coil into the furnace too early makes it easy for the surface of the radiant coil to be contaminated during the construction of refractory materials later; (3) It is difficult to adjust the position of the radiant coil, and welding deviation is easy to occur when welding it with the TLE pipeline of the ethylene cracking furnace.

[0006] Because radiant coils operate at high temperatures, they must be replaced as a whole after a certain number of years of use. There are generally two methods for replacing coils after a certain period: One method involves the coils entering the furnace as sections through the manhole and then being welded together inside the furnace. The disadvantages of this method are the large amount of on-site welding work, difficulty in controlling welding quality and assembly precision, and a long construction period. The other method involves the entire radiant coil assembly entering the furnace from the bottom. The disadvantages of this method are the need to temporarily dismantle the burners and related pipelines at the bottom of the pyrolysis furnace, the air preheater and related pipelines, and the coking pipelines returning to the furnace, and then restore them after the furnace tubes are in place. This makes the construction plan complex and technically difficult; furthermore, this method requires rotating the coils from horizontal to vertical within the furnace, which is not feasible in the confined space of the furnace. Summary of the Invention

[0007] The purpose of this invention is to address at least one deficiency in the prior art by providing an apparatus and method for welding, sag testing, and installation of radiant coils. This apparatus has a trolley capable of sliding along a guide rail. The straight tube of the radiant coil can be installed in the receiving cavity together with the positioning packaging frame without disassembling it, and the entire assembly is lifted to sag the straight tube. This allows for welding of bent tubes while suspended, and also facilitates sag testing. Furthermore, whether during initial installation or replacement installation, this apparatus facilitates the installation of the radiant furnace tubes and their connection to the TLE pipeline of the ethylene cracking furnace by placing the guide rail on top of the furnace.

[0008] To achieve the above objectives, the present invention provides an apparatus for welding, sag testing, and installation of radiant coils, wherein the radiant coils are used in an ethylene cracking furnace, and the radiant coils include straight pipes and bent pipes. The apparatus includes:

[0009] Guide rails are provided on both sides of the top of the ethylene cracking furnace;

[0010] A trolley is slidably mounted on the guide rail. The trolley has an internal receiving cavity for accommodating the straight tube. The trolley is equipped with a lifting adjustment component and a horizontal adjustment component. The lifting adjustment component is used to adjust the height of the straight tube, and the horizontal adjustment component is used to adjust the horizontal movement of the straight tube.

[0011] Optionally, the cross-section of the guide rail is L-shaped.

[0012] Optionally, the trolley includes a rectangular frame, the frame having an open-side receiving cavity, and a limiting beam detachably provided on the open side of the receiving cavity.

[0013] Optionally, a first roller is provided below the trolley to roll into contact with the bottom surface of the guide rail, and second rollers are provided on both sides of the trolley to engage with the sides of the guide rail.

[0014] Optionally, the lifting adjustment assembly includes a lifting screw, which is threadedly connected to the trolley. The lower end of the lifting screw is connected to the first roller, and the upper end of the lifting screw is provided with a handwheel.

[0015] Optionally, a plurality of the straight tubes are connected to a positioning packaging frame, the positioning packaging frame including two positioning beams arranged in parallel, the plurality of the straight tubes being fixed between the two positioning beams, the two positioning beams being connected by a connecting beam, and the two ends of the positioning beams being able to overlap the cavity wall of the receiving cavity.

[0016] Optionally, the leveling assembly includes an adjusting nut and a first adjusting bolt, the adjusting nut being fixed to the cavity wall, and each of the first adjusting bolts passing through the two positioning beams and one adjusting nut and threadedly engaging with the adjusting nut.

[0017] Optionally, the leveling assembly further includes a second adjusting bolt, which is threaded to both sides of the trolley, and the stud portion of the second adjusting bolt can penetrate the trolley and extend outward from the trolley.

[0018] Optionally, an elastic component is provided between the second roller and the side wall of the trolley.

[0019] The present invention also provides a method for welding, sag testing, and installing radiant coils, utilizing the aforementioned apparatus for welding, sag testing, and installing radiant coils, the method comprising:

[0020] Multiple straight tubes fixed in the positioning packaging frame are installed in the receiving cavity of the trolley;

[0021] The trolley and multiple straight tubes fixed in the positioning packaging frame are lifted up, so that the multiple straight tubes are in a suspended state;

[0022] The bent pipe is welded to the straight pipe to form a radiant coil and a suspension test is performed.

[0023] The guide rail is set on top of the ethylene cracking furnace and the positioning packaging rack with the radiant coil and the trolley are placed on the guide rail;

[0024] The multiple radiant coils are adjusted vertically and horizontally to connect with the TLE piping of the ethylene cracking furnace.

[0025] This invention provides an apparatus and method for welding, sag testing, and installation of radiant coils. Its advantages include: the apparatus has a trolley that can slide along a guide rail; the straight tube of the radiant coil can be installed in the receiving cavity together with the positioning packaging frame without disassembling it, and the entire assembly is lifted to sag the straight tube. This allows for welding of bent tubes while suspended, and also facilitates sag testing. Furthermore, whether during initial installation or replacement, the apparatus facilitates the installation of the radiant furnace tubes and their connection to the TLE pipeline of the ethylene cracking furnace by placing the guide rail on top of the furnace. The method, utilizing the aforementioned apparatus for welding, sag testing, and installation of radiant coils, enables the welding of straight and bent tubes of the radiant coil, sag testing, and installation into the ethylene cracking furnace as needed. This not only improves work efficiency but also enhances the accuracy of welding, sag testing, and installation.

[0026] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0027] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the invention.

[0028] Figure 1 A schematic diagram of an apparatus for welding, sag testing and installation of radiant coils according to an embodiment of the present invention is shown.

[0029] Figure 2 A top view schematic diagram of an apparatus for welding, sag testing and installation of radiant coils according to an embodiment of the present invention is shown.

[0030] Figure 3 A schematic diagram of the end face structure of an apparatus for radiant coil assembly welding, suspension testing and installation according to an embodiment of the present invention is shown.

[0031] Figure 4 A schematic diagram of the structure of an apparatus for welding, suspending, and installing radiant coils according to an embodiment of the present invention is shown before jacking.

[0032] Figure 5 A schematic diagram of the structure of an apparatus for welding, suspending, and installing radiant coils according to an embodiment of the present invention is shown after being lifted.

[0033] Figure 6 A flowchart is shown for a method of welding, sag testing and installation of radiant coils according to an embodiment of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Straight pipe; 2. Bend; 3. Guide rail; 4. Trolley; 5. Receiving cavity; 6. Frame; 7. Limiting beam; 8. First roller; 9. Second roller; 10. Lifting screw; 11. Handwheel; 12. Positioning packaging rack; 13. Positioning beam; 14. Adjusting nut; 15. First adjusting bolt; 16. Second adjusting bolt; 17. LTE pipeline. Detailed Implementation

[0036] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0037] This invention provides an apparatus for welding, sag testing, and installation of radiant coils used in ethylene cracking furnaces. The radiant coils include straight pipes and bent pipes. The apparatus includes:

[0038] Guide rails are installed on both sides of the top of the ethylene cracking furnace;

[0039] The trolley is slidably mounted on the guide rail. The trolley has an internal receiving cavity for accommodating the straight tube. The trolley is equipped with a lifting adjustment component and a horizontal adjustment component. The lifting adjustment component is used to adjust the height of the straight tube, and the horizontal adjustment component is used to adjust the horizontal movement of the straight tube.

[0040] Specifically, during assembly welding, the straight pipe fixed on the positioning packaging frame is placed in the receiving cavity of the trolley, and then the trolley and the straight pipe are lifted together to a vertically suspended state. The bend and straight pipe are then assembled and welded in this suspended state, and a suspension test can also be performed. When assembling with the TLE pipeline of the ethylene cracking furnace, the trolley and the welded bend of the straight pipe are placed together on the guide rail. The distance between the top of the straight pipe of the radiant coil and the TLE pipeline is adjusted using the lifting and horizontal adjustment components, thus achieving assembly welding in a free-suspension state. This device is used for factory and on-site assembly welding of radiant coils for ethylene cracking furnaces. It can closely approximate the working state of the radiant coils, resulting in low assembly stress and high precision, which facilitates improved assembly quality, suspension testing, and installation efficiency, while reducing the need for radiant coil straightening work.

[0041] Optionally, the guide rail has an L-shaped cross-section.

[0042] Specifically, the bottom and side surfaces of the guide rails are connected to form an L-shape, which is used to support the trolley and to horizontally limit the trolley, respectively.

[0043] Optionally, the trolley includes a rectangular frame with an open-side receiving cavity inside the frame, and a limit beam is detachably provided on the open side of the receiving cavity.

[0044] Specifically, the frame includes a rectangular frame and two beams set within the rectangular frame, forming an accommodating space between the two beams. Multiple reinforcing ribs can also be set between the beams and the rectangular frame. One side of the rectangular frame has an opening, forming an open accommodating cavity. The limiting beam is detachably connected to the opening. When it is necessary to put multiple straight tubes fixed in the positioning packaging frame into the accommodating cavity, the limiting beam can be removed to facilitate the insertion of the multiple straight tubes fixed in the positioning packaging frame. After insertion, the limiting beam is reinstalled to close the accommodating cavity, and the limiting beam can support the positioning packaging frame.

[0045] Optionally, a first roller is provided below the trolley to roll in cooperation with the bottom surface of the guide rail, and second rollers are provided on both sides of the trolley to cooperate with the sides of the guide rail.

[0046] Specifically, the first roller rolls with the bottom surface of the guide rail to support the trolley, while the second roller rolls with the side of the guide rail to limit and guide movement of the trolley.

[0047] Optionally, the lifting adjustment assembly includes a lifting screw, which is threadedly connected to the trolley. The lower end of the lifting screw is connected to the first roller, and the upper end of the lifting screw is provided with a handwheel.

[0048] Specifically, multiple first rollers and second rollers are respectively provided on both sides of the frame. Among the multiple first rollers, at least two rollers on one side of the frame are connected to the lower end of the lifting screw. The rollers are rotatably mounted on the roller frame, and the roller frame is rotatably connected to the lower end of the lifting screw.

[0049] In one example, the lifting height of the trolley is 10-600mm.

[0050] Optionally, multiple straight tubes are connected to a positioning packaging frame, which includes two parallel positioning beams. Multiple straight tubes are fixed between the two positioning beams, and the two positioning beams are connected by a connecting beam. The two ends of the positioning beams can overlap the cavity wall of the receiving cavity.

[0051] Specifically, the positioning packaging frame can firmly fix the straight pipe and prevent it from tilting during the welding process.

[0052] Optionally, the leveling assembly includes an adjusting nut and first adjusting bolts. The adjusting nut is fixed to the cavity wall, and each first adjusting bolt passes through two positioning beams and an adjusting nut and is threaded into the adjusting nut.

[0053] Specifically, turning the first adjusting bolt allows the positioning packaging frame to move horizontally relative to the trolley through its threaded engagement with the adjusting nut.

[0054] In one example, adjusting the first adjusting bolt allows the trolley to move horizontally a distance b of 5-20 mm.

[0055] Optionally, the leveling assembly also includes a second adjusting bolt, which is threaded to both sides of the trolley, and the stud portion of the second adjusting bolt can penetrate the trolley and extend to the outside of the trolley.

[0056] Specifically, by turning the second adjusting bolt, the stud portion of the second adjusting bolt extends outward from the trolley and contacts the side of the guide rail, allowing the trolley to move horizontally relative to the guide rail.

[0057] In one example, the gap between the second roller and the side of the guide rail is 0-9.9 mm.

[0058] Optionally, an elastic component is provided between the second roller and the side wall of the trolley.

[0059] Specifically, the elastic component can be a compression spring, and a guide post can be installed inside the compression spring to improve the stability of the trolley when sliding relative to the slide rail.

[0060] The present invention also provides a method for welding, sag testing, and installing radiant coils, utilizing the aforementioned apparatus for welding, sag testing, and installing radiant coils, the method comprising:

[0061] Multiple straight tubes fixed in the positioning packaging frame are installed in the receiving cavity of the trolley;

[0062] The trolley and multiple straight tubes fixed in the positioning packaging frame are lifted up, so that the multiple straight tubes are in a suspended state;

[0063] The bent pipe is welded to the straight pipe to form a radiant coil and a suspension test is conducted.

[0064] The guide rail is set on top of the ethylene cracking furnace and the positioning packing rack and trolley with radiant coils are placed on the guide rail;

[0065] Multiple radiant coils are adjusted vertically and horizontally to connect with the TLE piping of the ethylene cracking furnace.

[0066] Example

[0067] like Figures 1 to 5 As shown, the present invention provides an apparatus for welding, sag testing, and installation of radiant coils. The radiant coils are used in an ethylene cracking furnace. The radiant coils include a straight pipe 1 and a bent pipe 2. The apparatus includes:

[0068] Guide rails 3 are installed on both sides of the top of the ethylene cracking furnace;

[0069] The trolley 4 is slidably mounted on the guide rail 3. The trolley 4 has a receiving cavity 5 inside, which is used to receive the straight tube 1. The trolley 4 is equipped with a lifting adjustment component and a horizontal adjustment component. The lifting adjustment component is used to adjust the height of the straight tube 1, and the horizontal adjustment component is used to adjust the horizontal movement of the straight tube 1.

[0070] In this embodiment, the cross-section of the guide rail 3 is L-shaped.

[0071] In this embodiment, the trolley 4 includes a rectangular frame 6, and the frame 6 has an open cavity 5 inside, with a limiting beam 7 detachably provided on the open side of the cavity 5.

[0072] In this embodiment, a first roller 8 is provided below the trolley 4 to roll and engage with the bottom surface of the guide rail 3, and second rollers 9 are provided on both sides of the trolley 4 to engage with the sides of the guide rail 3.

[0073] In this embodiment, the lifting adjustment assembly includes a lifting screw 10, which is threadedly connected to the trolley 4. The lower end of the lifting screw 10 is connected to the first roller 8, and the upper end of the lifting screw 10 is provided with a handwheel 11.

[0074] In this embodiment, multiple straight tubes 1 are connected to a positioning packaging frame 12. The positioning packaging frame 12 includes two positioning beams 13 arranged in parallel. Multiple straight tubes 1 are fixed between the two positioning beams 13. The two positioning beams 13 are connected by a connecting beam. The two ends of the positioning beams 13 can overlap the cavity wall of the receiving cavity 5.

[0075] In this embodiment, the horizontal adjustment assembly includes an adjusting nut 14 and a first adjusting bolt 15. The adjusting nut 14 is fixed to the cavity wall, and each first adjusting bolt 15 passes through two positioning beams 13 and an adjusting nut 14 and is threadedly engaged with the adjusting nut 14.

[0076] In this embodiment, the horizontal adjustment assembly also includes a second adjusting bolt 16, which is threadedly connected to both sides of the trolley 4. The stud portion of the second adjusting bolt 16 can penetrate the trolley 4 and extend to the outside of the trolley 4.

[0077] In this embodiment, an elastic component is provided between the second roller 9 and the side wall of the trolley 4.

[0078] The present invention also provides a method for welding, sag testing, and installing radiant coils, utilizing the aforementioned apparatus for welding, sag testing, and installing radiant coils, the method comprising:

[0079] Multiple straight tubes 1, which are fixed in the positioning packaging frame 12, are installed in the receiving cavity 5 of the trolley 4;

[0080] The trolley 4 and the multiple straight tubes 1 fixed in the positioning packaging frame 12 are lifted up, so that the multiple straight tubes 1 are in a suspended state;

[0081] Weld the bend 2 to the straight pipe 1 to form a radiant coil and conduct a suspension test;

[0082] The guide rail 3 is set on top of the ethylene cracking furnace and the positioning packaging rack 12 with radiant coil and the trolley 4 are placed on the guide rail 3.

[0083] Multiple radiant coils are adjusted vertically and horizontally to connect with the TLE piping of the ethylene cracking furnace.

[0084] In summary, when implementing the method for welding, sag testing, and installation of radiant coils provided by this invention, taking the welding of straight pipes 1 and bent pipes 2 of a radiant coil as an example, multiple straight pipes 1 fixed on the positioning packaging frame 12 can be placed in the receiving groove of the trolley 4, and then lifted as a whole so that the multiple straight pipes 1 are in a suspended state. At this time, the welding of bent pipes 2 can be carried out below the multiple straight pipes 1. During the welding process, the straight pipes 1 are always in a vertically suspended state, eliminating the adverse effects of gravity and welding thermal stress on coil forming. After the welding is completed, a sag test can be performed on the radiant coil in the suspended state to verify the welding accuracy of the coil.

[0085] Taking the installation of radiant coils in an ethylene cracking furnace as an example: First, fix two guide rails 3 on the top two sides of the ethylene cracking furnace respectively. Then, lift the welded radiant coils and trolleys 4 together after the suspension test and place them on the two guide rails 3, so that all the load during the installation process is transferred to the structural frame of the ethylene cracking furnace through the guide rails 3. In this process, the trolleys 4 can also be placed first, and the limiting beam 7 can be opened to open one side of the receiving cavity 5. Then, the radiant coils fixed in the positioning packaging frame 12 can be installed into the receiving cavity 5, and the limiting beam 7 can be installed. After that, the height of the trolleys 4 and radiant coils can be adjusted by turning the handwheel 11 through the lifting screw 10, and the horizontal position of the trolleys 4 and radiant coils can be adjusted by the first adjusting bolt 15 and the second adjusting bolt 16, so that the upper end of the straight pipe 1 can be connected to the LTE pipeline 17 of the ethylene cracking furnace, and the radiant coils can be accurately positioned.

[0086] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. An apparatus for welding, sag testing, and installation of radiant coils, the radiant coils being used in an ethylene cracking furnace, the radiant coils comprising straight pipes and bends, characterized in that, The device includes: Guide rails are provided on both sides of the top of the ethylene cracking furnace; A trolley is slidably mounted on the guide rail. The trolley has an internal receiving cavity for accommodating the straight tube. The trolley is equipped with a lifting adjustment component and a horizontal adjustment component. The lifting adjustment component is used to adjust the height of the straight tube, and the horizontal adjustment component is used to adjust the horizontal movement of the straight tube. The trolley is provided with a first roller that rolls with the bottom surface of the guide rail, and the trolley is provided with second rollers that roll with the sides of the guide rail on both sides. An elastic component is provided between the second roller and the side wall of the trolley. The lifting adjustment assembly includes a lifting screw, which is threadedly connected to the trolley. The lower end of the lifting screw is connected to the first roller, and the upper end of the lifting screw is provided with a handwheel. Multiple straight tubes are connected to a positioning packaging frame, which includes two parallel positioning beams. Multiple straight tubes are fixed between the two positioning beams, and the two positioning beams are connected by a connecting beam. The two ends of the positioning beams can overlap the cavity wall of the receiving cavity. The horizontal adjustment assembly includes an adjusting nut and a first adjusting bolt. The adjusting nut is fixed to the cavity wall, and each of the first adjusting bolts passes through two positioning beams and one adjusting nut and is threaded into the adjusting nut. The leveling assembly also includes a second adjusting bolt, which is threaded to both sides of the trolley, and the stud portion of the second adjusting bolt can penetrate the trolley and extend outward from the trolley.

2. The apparatus for welding, sag testing, and installation of radiant coils according to claim 1, characterized in that, The guide rail has an L-shaped cross-section.

3. The apparatus for welding, sag testing, and installation of radiant coils according to claim 1, characterized in that, The trolley includes a rectangular frame, and the frame has an internal receiving cavity that is open on one side. A limiting beam is detachably provided on the open side of the receiving cavity.

4. A method for welding, sag testing, and installation of radiant coils, utilizing the apparatus for welding, sag testing, and installation of radiant coils according to any one of claims 1-3, characterized in that, The method includes: Multiple straight tubes fixed in the positioning packaging frame are installed in the receiving cavity of the trolley; The trolley and multiple straight tubes fixed in the positioning packaging frame are lifted up, so that the multiple straight tubes are in a suspended state; The bent pipe is welded to the straight pipe to form a radiant coil and a suspension test is performed. The guide rail is set on top of the ethylene cracking furnace and the positioning packaging rack with the radiant coil and the trolley are placed on the guide rail; The multiple radiant coils are adjusted vertically and horizontally to connect with the TLE piping of the ethylene cracking furnace.

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