A modular construction method for coil heat exchangers suitable for various types of boilers

Abstract

The present invention discloses a modular construction method for coil heat exchangers for various models of boilers, comprising the following steps: designing and manufacturing a packaging frame for the coil heat exchanger, modularly manufacturing the coil heat exchanger, installing a combined lifting tool, and modularly installing the coil heat exchanger. The modular construction method is applicable to the overall manufacturing, transportation, and overturning and hoisting of coil heat exchangers for various models of boilers, effectively solving the problems of large coil heat exchangers being inconvenient for overturning and hoisting, high-altitude assembly of hangers, high-altitude welding of headers, and pressure testing, thereby optimizing the construction process, saving costs, and effectively improving construction safety.

Description

Technical field

[0001] The present invention relates to the manufacturing and installation technology of waste heat boilers for thermal power plants, waste incineration plants, etc., and in particular to a modular construction method for coil heat exchangers suitable for various types of boilers. [Background Technology]

[0002] In the horizontal section of waste heat boilers in large power plants and waste incineration stations, there are a large number of coil heat exchangers, such as Figure 1 As shown, the existing coil heat exchanger consists of an upper suspension beam 1', elastic hangers 2', two headers 3', and a lower coil heat exchanger 4' (tube bundle). The header 3' on one side is provided with an inlet 30', and the header 3' on the other side is provided with an outlet 31'. Each coil heat exchanger has approximately 20 elastic hangers 2', and has approximately 60 small-diameter pressure pipe welds with the header 3'. Each elastic hanger 2' is provided with a basket bolt 20'.

[0003] In the traditional construction process, the lower coil heat exchanger 4' (tube bundle) is first manufactured and hoisted into the boiler, and then the suspension beam 1' and the elastic hanger 2' are bolted together and the lower coil heat exchanger 4' and the header 3' are welded together. This process has many problems: (1) The coil heat exchanger is built horizontally and installed vertically, and needs to be turned over before installation. In the traditional construction method, the lower coil heat exchanger lacks a fulcrum, making it difficult to fix the lock. Moreover, since the coil heat exchanger is composed of small-diameter steel pipes, it is very easy to cause damage to the pipes. (2) The lower coil heat exchanger is hoisted first, and the elastic hanger and the welding header are assembled at high altitude. The construction is difficult, requires large-scale hoisting resources, and is costly. (3) After the lower coil heat exchanger 4' and the header 3' are welded at high altitude, a water pressure test is required.

[0004] The traditional construction method of coil heat exchangers requires high-altitude assembly of hangers, welding of headers and water pressure testing of coil heat exchangers, which makes the construction difficult and costly. There is an urgent need to improve the existing construction technology. [Summary of the invention]

[0005] In view of the problem that existing coil heat exchangers require high-altitude assembly of hangers, welding of headers and water pressure testing, which makes construction difficult and costly, the present invention provides a modular construction method suitable for coil heat exchangers for various models of boilers. By producing modular tooling, the welding quality and production efficiency are improved, and costs are effectively saved, thereby improving the lifting efficiency and achieving the goal of reducing costs and increasing efficiency.

[0006] The technical solution adopted by the present invention to solve its technical problem is:

[0007] A modular construction method for coil heat exchangers for various types of boilers, comprising the following steps:

[0008] Step S1: Design and manufacture a packaging frame for the coil heat exchanger, wherein the packaging frame is suitable for manufacturing, transporting, and hoisting various types of heat exchangers and is reusable;

[0009] Step S2, modular production of the coil heat exchanger, the coil heat exchanger is directly produced in the cradle produced in step S1;

[0010] Step S3: Install the modular hoisting tool. Install the modular hoisting tool on the upper part of the coil heat exchanger. After installation, the modular production of the coil heat exchanger is completed. The same modular hoisting tool can be used to hoist coil heat exchangers of different models.

[0011] The combined lifting fixture includes an upper lifting lug, a lifting frame, a lower lifting lug, a connecting plate, and a combined self-locking latch assembly. The upper lifting lug, the lifting frame, and the lower lifting lug are fixed by welding, and the lower lifting lug is distributed according to the layout characteristics of the upper suspension beam of the coil heat exchanger.

[0012] The connecting plate is detachably connected to the lower lifting ear through a combined self-locking latch assembly. According to the layout number and spacing characteristics of the upper suspension beams of the coil heat exchanger, different numbers of connecting plates are connected to realize the connection between the overall lifting device and coil heat exchangers of different models, thereby performing the overturning and lifting of the coil heat exchanger.

[0013] Step S4: modularly installing the coil heat exchanger. During the installation, the coil heat exchanger's lifting force points are all on the temporary packaging frame.

[0014] Furthermore, the step S1 further includes:

[0015] Step S1.1: During the design, the maximum load-bearing weight and maximum dimensions of the packaging frame should be determined after comprehensive consideration of all types of coil heat exchangers.

[0016] Step S1.2: Determine the number and spacing of the suspension support beams and the spacing of the tube bundles based on the coil heat exchanger components. Also determine the length of the support beams and the bolt hole spacing of the heat exchanger packaging frame.

[0017] Step S1.3, and determining the position of the lifting lugs in the heat exchanger packaging frame according to the weight and center of gravity of the packaging frame.

[0018] Furthermore, the step S2 further includes welding the elastic hanger rods and the header, leaving only one pipe inlet and outlet, and completing the hydraulic pressure test as a whole before leaving the factory; specifically, the following steps are included:

[0019] Step S2.1: Horizontally weld and integrate the pipes and headers of the coil heat exchanger in the packaging frame. Sleepers are required to secure the coils to ensure spacing between the upper and lower pipes. After the coil heat exchanger is erected, the sleepers must be removed.

[0020] Step S2.2: Install the suspension beams. Use bolts to secure the suspension beams corresponding to the tube bundles to the supporting beams of the packaging frame corresponding to the coil heat exchanger.

[0021] Step S2.3: Install the elastic hangers. Connect all single-row hangers to the header and the suspension beam from bottom to top, and tighten the elastic hangers with turnbuckles.

[0022] Step S2.4: hydraulic pressure test. The assembled coil heat exchanger has only one outlet and one inlet, and the hydraulic pressure test is started.

[0023] Furthermore, the step S3 further includes:

[0024] The combined self-locking pin assembly includes a connecting pin, a retaining ring, a limiting pin and a self-locking ring. The retaining ring is welded to one end of the connecting pin to form a limiting structure. The other end of the connecting pin has a hole for connecting the limiting pin and the retaining ring to form a detachable self-locking structure.

[0025] The self-locking ring is inserted into the upper part of the fiber pin and can be flipped. When installing the self-locking ring, the self-locking ring needs to be flipped downward to pass through the connecting pin to achieve the self-locking function. When removing the structure corresponding to the self-locking ring, the self-locking ring needs to be flipped upward to release the self-locking relationship with the connecting pin, so that the combined self-locking pin assembly can be gradually removed as a whole.

[0026] Furthermore, in step S4, the entire coil heat exchanger is hoisted into the boiler using a primary crane and hung on the upper part of the boiler steel structure; during installation, two cranes are used to turn the horizontal coil heat exchanger over and erect it, using locks, hanging beams, and pulleys; the process specifically includes the following steps:

[0027] Step S4.1: Two cranes simultaneously raise the hooks and lift the coil heat exchanger about 800 mm off the ground;

[0028] Step S4.2: The tail crane remains stationary, the main crane slowly rises and approaches the tail crane, and the equipment begins to reverse until the heat exchanger module stands upright and rests on the ground;

[0029] Step S4.3: Unhook the tail crane and remove the tail crane lock;

[0030] Step S4.4: Use guy ropes to fix the packaging frame to the ground to prevent the coil heat exchanger from being affected by wind and tilting;

[0031] Step S4.5: After removing the detachable portion of the upper portion of the packaging frame, the main crane lifts the coil heat exchanger out of the packaging frame;

[0032] Step S4.6: Lift the coil heat exchanger to the module height and place it inside the module boiler. Place the suspension beam on the upper part of the coil heat exchanger above the steel structure.

[0033] Furthermore, the step S4 also includes: during installation, using a wheel-changing assembly to increase the lifting force points, reducing the deformation of the coil heat exchanger during the lifting process, thereby reducing the strength requirements for the packaging frame and reducing material consumption.

[0034] The beneficial effects of the present invention are:

[0035] The modular construction method provided by the present invention, first, reduces the assembly work on the construction site, making the production of coil heat exchangers more flexible, and can be produced simultaneously at different locations, speeding up the construction progress through modular installation; secondly, it reduces a large number of high-altitude operations, such as the assembly of elastic hangers, the welding of tube bundles and headers, high-altitude water pressure testing, etc.; and the combined boiler coil heat exchanger lifting tooling is reusable. Under normal circumstances, a boiler has 10 to 30 heat exchangers. By designing universal tooling, the tooling utilization rate is improved, and labor input is reduced, a large amount of material costs can be saved, the lifting efficiency is improved, and the lifting safety is improved.

Brief Description of the Drawings

[0036] Figure 1 It is a schematic diagram of the three-dimensional structure of a coil heat exchanger in the prior art;

[0037] Figure 2 is a schematic diagram of the three-dimensional structure of the packaging frame in step S1 of the present invention;

[0038] Figure 3 This is a schematic diagram of the main structure of the packaging frame in step S1 of the present invention;

[0039] Figure 4 This is a schematic diagram of the three-dimensional structure of the coil heat exchanger and the packaging frame after assembly in step S2 of the present invention, with the elastic suspension rod omitted;

[0040] Figure 5 This is a schematic diagram of the main structure of the coil heat exchanger and the packaging frame after assembly in step S2 of the present invention;

[0041] Figure 6 It is a schematic diagram of the three-dimensional structure of the lifting tool in step S3 of the present invention;

[0042] Figure 7 It is an enlarged schematic diagram of the three-dimensional structure of the lower lifting ear in step S3 of the present invention;

[0043] Figure 8This is an enlarged schematic diagram of the main structure of the connecting pin in step S3 of the present invention;

[0044] Figure 9 This is an enlarged schematic diagram of the main structure of the retaining ring in step S3 of the present invention;

[0045] Figure 10 yes Figure 9 A schematic diagram of the side structure of the retaining ring;

[0046] Figure 11 is an enlarged schematic side view of the limit latch structure in step S3 of the present invention;

[0047] Figure 12 It is an enlarged schematic diagram of the assembly of the combined self-locking latch assembly in step S3 of the present invention;

[0048] Figure 13 This is a schematic diagram of the front view of the horizontal placement of the modularized production and installation tooling in step S3 of the present invention;

[0049] Figure 14 It is a schematic diagram of modular hoisting in step S4 of the present invention;

[0050] Figure 1 5 is a schematic diagram of the hoisting process in step S4 of the present invention;

[0051] Figure 1 6 is a schematic diagram of the process of hoisting and placing the component into the boiler for fixing in step S4 of the present invention. [Specific implementation method]

[0052] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0053] A modular construction method for coil heat exchangers for various types of boilers, comprising the following steps:

[0054] Step S1, such as Figure 2 and Figure 3 As shown in the figure, a packaging frame a for coil heat exchanger is designed and manufactured. The packaging frame is suitable for manufacturing, transporting and hoisting various types of heat exchangers and can be recycled. Figure 2 and Figure 3 In the figure, it is the packaging frame corresponding to one type of coil heat exchanger. Different types of coil heat exchangers have different numbers of coil heat exchangers (tube bundles) and different hanging beams. Figure 3In the figure, the upper virtual frame part of the packaging frame a is a detachable part.

[0055] Step S1.1: During the design, the maximum load-bearing weight and maximum dimensions of the packaging frame should be determined after comprehensive consideration of all types of coil heat exchangers;

[0056] Step S1.2: Based on the coil heat exchanger components, determine the number and spacing of the suspension support beams, as well as the spacing of the coil heat exchangers (tube bundles). Also determine the lengths and bolt hole spacing of the support beams a1 and a2 of the heat exchanger packaging frame a.

[0057] Step S1.3, and determining the positions of the main lifting lug a3 and the spare lifting lug a4 in the heat exchanger packaging frame according to the weight and the center of gravity of the packaging frame.

[0058] Step S2, such as Figures 2 to 5 As shown, the coil heat exchanger is modularly manufactured. The coil heat exchanger is directly manufactured in the cradle manufactured in step S1. The elastic hangers and headers are all welded together, leaving only one pipe inlet and outlet. The whole unit is subjected to a hydraulic pressure test before being shipped out. Compared with the existing technology, the modular manufacturing method has a high manufacturing integrity, which is conducive to improving the quality of the heat exchanger and reducing the work of assembling the elastic hangers, welding, and testing at high altitude on the construction site. The method specifically includes the following steps:

[0059] Step S2.1, as Figure 5 As shown, in the packaging frame a, the pipes and header b1 of the coil heat exchanger are horizontally welded and integrated. The coils need to be fixed with sleepers b2 to ensure the spacing between the upper and lower pipes. After the coil heat exchanger is erected, the sleepers need to be removed.

[0060] Step S2.2: Install the suspension beams. Use bolts to secure the suspension beams b4 corresponding to the tube bundle b3 (coil heat exchanger) to the support beams a1 and a2 of the packaging frame a corresponding to the coil heat exchanger.

[0061] Step S2.3: Install the elastic hangers b5. Connect all single-row hangers from bottom to top to the header b1 and the suspension beam b4. Use the turnbuckles b6 to tighten the elastic hangers b5.

[0062] Step S2.4, hydraulic pressure test: the assembled coil heat exchanger has only one outlet and one inlet. Compared with the traditional construction process, the hydraulic pressure test can be started.

[0063] Step S3, such as Figure 6 to Figure 1 As shown in Figure 3, install the combined lifting fixture and install it on the upper part of the coil heat exchanger. After installation, the modular production of the coil heat exchanger is completed, and the same combined lifting fixture can be used to lift different types of coil heat exchangers.

[0064] In this embodiment, Figure 6 to Figure 1 As shown in Figure 3, the combined lifting tooling includes an upper lifting ear 1, a lifting frame 2, a lower lifting ear 3, a connecting plate 4 and a combined self-locking pin assembly 5. The upper lifting ear 1, the lifting frame 2 and the lower lifting ear 3 are fixed by welding, and the lower lifting ear 3 is distributed according to the layout characteristics of the upper suspension beam of the coil heat exchanger; the connecting plate 4 is detachably connected to the lower lifting ear 3 through the combined self-locking pin assembly 5, and different numbers of connecting plates 4 are connected according to the layout number and spacing characteristics of the upper suspension beam of the coil heat exchanger to realize the connection between the overall lifting device and different types of coil heat exchangers, thereby performing the overturning and lifting of the coil heat exchanger.

[0065] The combined self-locking latch assembly 5 includes a connecting latch 5.1, a retaining ring 5.2, a limiting latch 5.3 and a self-locking ring 5.4. The retaining ring 5.2 is welded to one end of the connecting latch 5.1 to form a limiting structure, and the other end of the connecting latch 5.1 has a hole and is used to connect the limiting latch 5.3 and the retaining ring 5.2 to form a detachable self-locking structure; the self-locking ring 5.4 is inserted into the upper part of the fiber latch 5.3 and can be flexibly flipped. When installing the self-locking ring 5.4, the self-locking ring 5.4 needs to be flipped downward to pass through the connecting latch 5.1 to achieve the self-locking function. When removing the structure corresponding to the self-locking ring 5.4, the self-locking ring 5.4 needs to be flipped upward to release the self-locking relationship with the connecting latch 5.1, so that the combined self-locking latch assembly 5 can be gradually dismantled as a whole.

[0066] Step S4, as Figures 14 to 16 As shown, the modular installation of the coil heat exchanger involves hoisting the entire coil heat exchanger into the boiler using a single crane and hanging it on the upper part of the boiler steel structure. During installation, two cranes are used to turn the horizontal coil heat exchanger over and erect it, using locks, lifting beams, and pulleys. The specific steps include:

[0067] Step S4.1, as Figure 14 and Figure 1 As shown in Figure 5, two cranes simultaneously lift the hooks and lift the coil heat exchanger about 800mm off the ground;

[0068] Step S4.2, such as Figure 1 As shown in Figure 5, the tail crane 6 does not move, the main crane 7 slowly rises and approaches the tail crane, and the equipment begins to reverse until the heat exchanger module is upright and placed on the ground;

[0069] Step S4.3: Unhook the tail crane and remove the tail crane lock;

[0070] Step S4.4: Use guy ropes to fix the packaging frame to the ground to prevent the coil heat exchanger from being affected by wind and tilting;

[0071] Step S4.5: After removing the detachable portion of the upper portion of the packaging frame, the main crane lifts the coil heat exchanger out of the packaging frame;

[0072] Step S4.6: Lift the coil heat exchanger to the module height and place it inside the module boiler. Place the suspension beam on the upper part of the coil heat exchanger above the steel structure.

[0073] During installation, the coil heat exchanger's lifting load points are all on the temporary packaging frame, which minimizes damage to the coil heat exchanger. In addition, during installation, the use of a wheel changer increases the lifting load points, reducing deformation of the coil heat exchanger during the lifting process, thereby reducing the strength requirements of the packaging frame and reducing material consumption.

[0074] In this embodiment, the construction method can effectively reduce the assembly work on the construction site, making the production of the coil heat exchanger more flexible. It can be produced simultaneously at different locations, and the construction progress can be accelerated through modular installation. It can also reduce a large amount of high-altitude operations, such as the assembly of elastic hangers, welding of tube bundles and headers, high-altitude water pressure testing, etc.; moreover, the corresponding coil heat exchanger lifting tooling can be reused. Under normal circumstances, a boiler has 10 to 30 heat exchangers. By designing universal tooling, a large amount of material costs can be saved and the safety of lifting can be effectively improved.

[0075] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Any equivalent changes made based on the shape, structure and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A modular construction method for coil heat exchangers for various types of boilers, characterized in that: The modular construction method includes the following steps: Step S1, designing and manufacturing a packaging frame for the coil heat exchanger, wherein the packaging frame is suitable for manufacturing, transporting, and hoisting various types of heat exchangers and is reusable; Step S2, modular production of the coil heat exchanger, the coil heat exchanger is directly produced in the cradle produced in step S1; Step S2.1: Horizontally weld and integrate the pipes and headers of the coil heat exchanger in the packaging frame. Sleepers are required to secure the coils to ensure spacing between the upper and lower pipes. After the coil heat exchanger is erected, the sleepers must be removed. Step S2.2: Install the suspension beams. Use bolts to secure the suspension beams corresponding to the tube bundles to the supporting beams of the packaging frame corresponding to the coil heat exchanger. Step S2.3: Install the elastic hangers. Connect all single-row hangers to the header and the suspension beam from bottom to top, and tighten the elastic hangers with turnbuckles. Step S2.4: Hydrostatic test. The assembled coil heat exchanger has only one outlet and one inlet. Hydrostatic test is started. Step S3: Install the modular hoisting tool. Install the modular hoisting tool on the upper part of the coil heat exchanger. After installation, the modular production of the coil heat exchanger is completed. The same modular hoisting tool can be used to hoist coil heat exchangers of different models. The combined lifting fixture comprises an upper lifting lug (1), a lifting frame (2), a lower lifting lug (3), a connecting plate (4) and a combined self-locking latch assembly (5); the upper lifting lug (1), the lifting frame (2) and the lower lifting lug (3) are fixed by welding, and the lower lifting lug (3) is distributed according to the layout characteristics of the upper suspension beam of the coil heat exchanger; The connecting plate (4) is detachably connected to the lower lifting lug (3) via a combined self-locking latch assembly (5), and different numbers of connecting plates (4) are connected according to the layout number and spacing characteristics of the upper suspension beams of the coil heat exchanger to achieve connection between the overall lifting device and coil heat exchangers of different models, thereby performing the overturning lifting of the coil heat exchanger; Step S4: modular installation of the coil heat exchanger, during which the coil heat exchanger hoisting force points are all on a temporary packaging frame; Step S4.1: Two cranes simultaneously raise the hooks and lift the coil heat exchanger 800 mm off the ground; Step S4.2: The tail crane remains stationary, the main crane slowly rises and approaches the tail crane, and the equipment begins to reverse until the heat exchanger module stands upright and rests on the ground; Step S4.3: Unhook the tail crane and remove the tail crane lock; Step S4.4: Use guy ropes to fix the packaging frame to the ground to prevent the coil heat exchanger from being affected by wind and tilting; Step S4.5: After removing the detachable portion of the upper portion of the packaging frame, the main crane lifts the coil heat exchanger out of the packaging frame; Step S4.6: Lift the coil heat exchanger to the module height and place it inside the module boiler. Place the suspension beam on the upper part of the coil heat exchanger above the steel structure.

2. The modular construction method for coil heat exchangers for various types of boilers according to claim 1, characterized in that: The step S1 further includes: Step S1.1: During the design, the maximum load-bearing weight and maximum dimensions of the packaging frame should be determined after comprehensive consideration of all types of coil heat exchangers. Step S1.2: Determine the number and spacing of the suspension support beams and the spacing of the tube bundles based on the coil heat exchanger components. Also determine the length of the support beams and the bolt hole spacing of the heat exchanger packaging frame. Step S1.3, and determining the position of the lifting lugs in the heat exchanger packaging frame according to the weight and center of gravity of the packaging frame.

3. The modular construction method for coil heat exchangers for various types of boilers according to claim 1, characterized in that: The step S2 also includes welding the elastic suspension rods and the header, leaving only one pipe inlet and outlet, and completing the water pressure test as a whole before leaving the factory.

4. The modular construction method for coil heat exchangers for various types of boilers according to claim 1, characterized in that: The step S3 further includes: The combined self-locking latch assembly (5) comprises a connecting latch (5.1), a retaining ring (5.2), a limiting latch (5.3) and a self-locking ring (5.4); a retaining ring (5.2) is welded to one end of the connecting latch (5.1) to form a limiting structure; and a hole is opened at the other end of the connecting latch (5.1) and is used to connect the limiting latch (5.3) and the retaining ring (5.2) to form a detachable self-locking structure. The self-locking ring (5.4) is inserted into the upper part of the limit pin (5.3) and can be flexibly flipped. When installing the self-locking ring (5.4), the self-locking ring (5.4) needs to be flipped downward to pass through the connecting pin (5.1), thereby realizing the self-locking function. When removing the structure corresponding to the self-locking ring (5.4), the self-locking ring (5.4) needs to be flipped upward to release the self-locking relationship with the connecting pin (5.1), thereby gradually removing the combined self-locking pin assembly (5) as a whole.

5. The modular construction method for coil heat exchangers for various types of boilers according to claim 1, characterized in that: In step S4, the entire coil heat exchanger is hoisted into the boiler using a primary crane and hung on the upper part of the boiler steel structure; during installation, locks, hanging beams and pulleys are used, and two cranes are used to turn the horizontal coil heat exchanger over and erect it.

6. The modular construction method for coil heat exchangers for various types of boilers according to claim 5, characterized in that: The step S4 also includes: during installation, using a wheel-changing assembly to increase the lifting force points, reducing the deformation of the coil heat exchanger during the lifting process, thereby reducing the strength requirements for the packaging frame and reducing material consumption.

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