Method for manufacturing combustor gas manifold and improved manifold obtained thereby
By forming grooves on the gas manifold wall and using laser welding to fix the partition components, the problems of high energy consumption and space occupation in the prior art are solved, enabling the manufacture of a low-cost, compact burner with smaller nozzle spacing and support for multi-stage flame generation.
Patent Information
- Application Number
- CN202480039875.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-06-20
- Filing Date
- 2024-06-12
- Publication Date
- 2026-01-13
AI Technical Summary
Existing methods for manufacturing burner gas manifolds suffer from high energy consumption, large space requirements, high costs, and inflexible nozzle arrangement. In particular, the brazing process is complex and not conducive to compact design.
A groove is formed on the wall of the gas manifold using laser welding or other self-fusion welding methods, and a partition component is inserted. The partition component is melted and fixed by a laser beam, avoiding material diffusion and achieving high-precision partitioning and compact design.
It reduces manufacturing energy consumption, space occupation, and costs, and allows for nozzle spacing of less than 17mm, enabling the design of a compact burner and multi-stage flame generation.
Smart Images
Figure CN121336072A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present invention relates to a method for manufacturing a gas manifold for a gas burner and a manifold made thereby. BACKGROUND
[0002] As is known, a burner gas manifold is a component for a product, for example a gas boiler, which distributes the gas to the various nozzles of the burner through this component.
[0003] This manifold can adopt various shapes, such as for example a tubular shape (with a circular or polygonal cross section), and its inside contains a longitudinal chamber which receives the gas from at least one pipe fixed outside the body of the manifold. Connected in this longitudinal chamber are the nozzles which allow the gas present in the chamber of the manifold to reach the various elements of the burner which generate the flame, for example the burner plates.
[0004] The nozzles are usually uniformly spaced apart by a certain distance, for example 17 mm, which is also usually present between the burner plates (or similar elements).
[0005] In order to divide the use of the burner and to allow the use of only some of the burner plates in this burner when required and desired to generate the flame, it is known to divide this chamber into a plurality of sections (each of which receives the gas from the pipe in the chamber) for example by using one or more dividing partitions or baffles arranged in the chamber of the manifold. This allows the gas to be delivered only into a section or portion of the chamber of the manifold and therefore to supply the gas only to part of the nozzles of the burner; this is done (by the burner control member) in order to achieve a low power operation of the burner when the user selects a certain temperature, for example to have a certain temperature condition required in the environment heated by a heating system which has a boiler with a split burner, or a certain temperature of the water heated by a water heater provided with this burner.
[0006] In order to divide the chamber of the manifold into two or more sections (as in the example below into two sections), it is known to insert a dividing partition or baffle into the manifold at the open end of the manifold (before arranging the corresponding bracket which closes the end and allows to support the manifold at both ends thereof). This insertion is performed using a suitable manipulator. The dividing partition or baffle is therefore brazed to the manifold.
[0007] This operation has many drawbacks. Primarily: the manipulator which introduces the dividing partition must have a certain configuration in order to obtain the correct movement of the partition of the chamber of the manifold in order to prevent the partition from jamming or being arranged incorrectly in this chamber.
[0008] In addition, the brazing welding operation can cause the material used for welding to diffuse in the chamber, possibly affecting the holes designed for the nozzles and thus making it difficult to arrange the nozzles in the desired manner.
[0009] In addition to this, the brazing welding is a high energy consumption process, since it requires the use of a furnace (usually gas heated) suitable for heating the material used for brazing welding to high temperatures (about 1000°C). This furnace is continuously running and even when it is not running (for example because it is undergoing maintenance) it should be kept at a minimum temperature to avoid the need for a long heating process when it is started.
[0010] All these factors result in a high consumption of energy and gas.
[0011] In addition, the above-mentioned furnace is a tunnel furnace which occupies a considerable area in the plant where the manifold is produced. In addition to this, the brazing welding itself presents intrinsic difficulties, so it must be performed in a non-oxidizing protective atmosphere and therefore by using facilities and gases which affect the operating costs.
[0012] Finally, this furnace requires a considerable maintenance of the internal system for moving the workpieces being processed and, for the above-mentioned reasons, the brazing welding must use a considerable number of workpieces. Therefore, it is important to provide said furnace with a refined but expensive management. SUMMARY
[0013] The object of the present invention is to provide a method for manufacturing a burner gas manifold which is improved with respect to the manufacturing methods of the prior art.
[0014] In particular, the object of the present invention is to provide a method of the above type whose implementation costs are significantly lower than those currently envisaged for the welding operations for manufacturing gas manifolds.
[0015] Another object of the present invention is to provide a method of the above type which allows to produce an arbitrary number of manifolds without generating economic level impacts and without the need to occupy a considerable space in the manufacturing plant.
[0016] Another object is to provide a method of the above type which allows to obtain a gas manifold for supplying a burner in which the flame is also able to be generated automatically at three sections of the burner.
[0017] Another object of the present invention is to provide a burner gas manifold which is more cost-effective than the manifolds currently obtained using the brazing welding method and in which the nozzles are able to approach each other in order to allow to provide a combustion chamber for the corresponding gas burner which is highly compact.
[0018] These and other objectives will become more apparent to those skilled in the art by means of the method for manufacturing a gas manifold and the manifold thereby obtained, as described in the corresponding appended claims. Attached Figure Description
[0019] To better understand the invention, the following figures are provided by way of non-limiting example only, wherein:
[0020] Figure 1 An exploded view shows the gas manifold according to the invention;
[0021] Figure 2 The assembled Figure 1 The gas manifold;
[0022] Figure 3 It shows that according to Figure 2 A cross-sectional view of line 3-3, in which a portion of the manifold is shown in an exploded view;
[0023] Figure 4 It shows that according to Figure 2 The cross-sectional view of line 3-3;
[0024] Figure 5 It shows that according to Figure 1 The cross-sectional view of line 5-5; and
[0025] Figure 6 It shows Figure 5 The view as seen from the left. Detailed Implementation
[0026] Referring to the figures mentioned above, the gas manifold according to the invention is generally designated 1. The gas manifold includes a tubular body 2 with a polygonal cross-section as shown, having two opposite ends 3 and 4, and walls 5, 6, 7, and 8 defining an internal cavity 9. A plurality of first through-holes 10 are provided in the walls 5 for corresponding nozzles 11, which are connected to the tubular body 2 of the manifold in any known manner and deliver gas from the gas manifold to the burner.
[0027] A second through hole 15 is provided in the wall 6, which is adapted to receive the end 16 of the pipe 17, which is adapted to introduce gas into the manifold 1. This end 16 of the pipe 17 is fixed to the body 2 of the manifold.
[0028] Members 19 are provided at the ends 3 and 4 of the tubular body 2. Members 19 are adapted to close the aforementioned (opening) ends 3 and 4 with a portion 20 thereof, and members 19 have brackets 21 for fixing to any known support (not shown).
[0029] Moreover, in the wall 6 there is provided a through slot 22 (arranged with its longitudinal axis K lying on a plane orthogonal to the longitudinal axis W of the tubular body 2) which preferably reaches the adjacent walls 5 and 6. This slot 22 is suitable for housing a partition member 23 which is suitable for partitioning the cavity (or chamber) 9 of the manifold into two portions 24 and 25, the respective holes 15 and therefore the ducts 17 opening into each of the two portions 24 and 25.
[0030] In the walls 5, 7 and 8 there are provided recesses (recesses 305, 307, 308, respectively) at the through slot or opening 22; such recesses define seats 30 for the partition member 23 which is inserted in a slidable manner into the seats 30, penetrating into the cavity or chamber 9 of the tubular body 2 through the slot 22.
[0031] This insertion is performed when implementing the method according to the present application, the first step of which provides, in particular, for forming said slot 22 in the wall 6, the ends 65, 67 of which are proximate to the walls 5 and 7 of the tubular body 2.
[0032] Therefore, the recesses 305, 307 and 308 are formed, that is to say, the seats 30 for the partition member 23 are provided. These recesses are required for the gas seal proximate to the partition member. However, these recesses can also be absent if such a seal is achieved due to suitable internal tolerances of the tubular body 2.
[0033] Obviously, the slot 22 and said seats 30 are provided according to the dimensions of such a partition member 23 and are in place in the tubular body 2 so as to define (along the longitudinal axis W of the tubular body 2) the portions 24 and 25 having the desired axial length according to the division desired for the generation of the flame by the burner.
[0034] After the above steps have been completed, the partition member is introduced into the slot 22 by sliding it in the recesses 305 and 307 until it reaches the recess 308. At this point, the partition member 23 is fixed, that is to say, welded, to the tubular body 2. This fixing or welding is performed by means of a self-fusible welding such as laser welding, electric arc welding, or by any other method falling within said definition (plasma welding, TIG welding, MIG welding or MAG welding).
[0035] By way of example, considering, for instance, the use of a laser to perform such a self-fusible welding, the laser welding operation is performed "by transmission" at the sides 5, 7 and 8, that is to say, the laser beam penetrates from the outside of the tubular body 2 according to a butt joint on the side 6. This causes the (metal) material with which such a body is made to locally melt and immediately cool. This fixes the partition member 23 in the seats 30.
[0036] The above operation (i.e. the action of the laser) also causes the peripheral portion of the partition member 23 in the seat 30 to melt, followed by the cooling of this material, which, in the cooling step, bonds with the material of the tubular body 2. This causes the partition member to be laser-welded in the seat 30.
[0037] Subsequently, the laser passes along the edge of the slot 22 on the wall 6 and at its ends 65, 67, causing the material of the partition member and the material of the tubular body 9 to locally melt and the slot to be closed, thus obtaining a butt strap.
[0038] Obviously, the material of the tubular body 2 and the material of the partition member 23 are identical (for example, they are steel) or are compatible so as to be tightly melted.
[0039] The laser used for the welding (penetrating or transmissive) is, for example, a fiber laser.
[0040] The advantage of the laser welding is that only the area to be melted and thus welded is heated; this avoids any subsequent positioning errors of the tubular body 2 and thus any deformation of the tubular body. Moreover, by means of the local laser welding, the melted material does not spread along the wall 5 of the tubular body 2, thus preventing the melted material from penetrating into the holes 10 closest to the welding area and at least partially clogging them (as can happen in the case of brazing welding).
[0041] In particular, thanks to the accuracy and precision of the laser welding and in view of the fact that the melted material does not spread along the wall 5 of the tubular body 2, the holes 10 can be approached for the seats 30 of the partition members 23. This allows to provide that the spacing between the holes 10 is less than the 17 mm commonly used in the prior art solutions, with a minimum of 10 mm. This leads to a reduction in the length of the manifold 1 along its longitudinal axis W and to a longitudinally compact burner, which is more compact than the burners containing partitions fixed therein for brazing welding.
[0042] Moreover, having the option of approaching the nozzles also allows to arrange a plurality of partition members in the tubular body 2 and, for example, to form three portions of the cavity or chamber of the manifold 9; this allows to have a further option of dividing the operation of the burner.
[0043] The method for manufacturing the gas manifold described allows to provide a method for dividing the cavity or chamber of the manifold into at least two portions 24 and 25, which is much less energy-consuming than the brazing welding process in the prior art. Moreover, the present invention does not require the preheating of the laser device of the prior art that performs the welding, just as this device does not occupy the space of the brazing furnace, which is advantageous for the size of the manufacturing plant.
[0044] Finally, a limited number of gas manifolds can be produced for use, for example, for manufacturing samples, using the method according to the present application.
[0045] A preferred embodiment of the present application has been described, in which the method of the present application is performed using a laser. However, as shown, other autogenous welding methods known to the skilled person can also be used, such as gas welding, arc welding, plasma welding, TIG welding, MIG welding and MAG welding.
[0046] Furthermore, according to the description, in any case other solutions can be obtained (such as one in which the slots 22 are formed in walls of the tubular body 2 other than the wall 6), which still fall within the protective scope of the present application as defined by the subsequent claims.
Claims
1. A method for manufacturing a gas manifold for a burner, the gas manifold (1) having a tubular body (2) having walls (5, 6, 7, 8), a first wall (5) having a plurality of first through holes (10) for corresponding nozzles (11) of the burner, and a second through hole (15) for a conduit (17) in a second wall (6), the conduit (17) being used to introduce gas into a cavity (9) inside the tubular body (2) of the gas manifold, the first through holes (10) for the nozzles (11) of the burner also opening into the cavity (9), the internal cavity (9) being divided into at least two parts (24, 25), characterized in that, The method provides: a) At least one through groove (22) is formed in the wall (6) of the wall (5, 6, 7, 8) of the tubular body (2) of the gas manifold. b) Insert the partition member (23) into the through groove (22) such that the partition member divides the internal cavity (9) of the tubular body (2) of the gas manifold into the two parts (24, 25). c) Performing a self-fusion welding of such a partition member (23) to the wall (5, 6, 7, 8) of the inner cavity (9) of the tubular body (2) of the aforementioned gas manifold. d) Perform autofusion welding of the partition member (23) along the aforementioned through groove (22), wherein the autofusion welding is selected as laser welding, arc welding, gas welding, TIG welding, MIG welding, MAG welding or plasma welding.
2. The method according to claim 1, characterized in that, Inside the cavity (9) of the tubular body (2) of the gas manifold, at least one of the walls (5, 7, 8) other than the wall with the through groove (22) is provided with a recess (305, 307, 308) suitable for receiving the partition member (23), the partition member (23) being slidably inserted into the at least one recess and the through groove and welded therein.
3. The method according to claim 2, characterized in that, A recess (305, 307, 308) is provided in each wall (5, 7, 8) that defines the recess (9) at the through groove (22), each recess (305, 307, 308) defining a seat (30) for the partition member (23), and such partition member is welded in the seat (30).
4. The method according to claim 1, characterized in that, The longitudinal axis (K) of the through groove (22) is located on a plane perpendicular to the longitudinal axis (W) of the tubular body (2) of the gas manifold.
5. The method according to claim 1, characterized in that, The burner nozzle (11) is associated with the through hole (10) of the tubular body (2) of the gas manifold, thereby maintaining the burner nozzle at a distance equal to or greater than 10 mm.
6. A burner gas manifold comprising a tubular body (2) having an internal cavity (9) having a longitudinal axis (W), the tubular body (2) having walls (5, 6, 7, 8), in which a plurality of first holes (10) for a nozzle (11) of a burner are provided in a first wall (5) of such walls (5, 6, 7, 8), and in a second wall (6) a plurality of second walls (15) for connecting a conduit (17) adapted to deliver gas to the aforementioned internal cavity (9), the nozzle (11) of the burner also opening into the internal cavity (9), the internal unit being divided into at least two parts (24, 25), and in which a partition member (23) is provided, the partition member (23) being adapted to divide such internal cavity (9) into said two parts (24, 25), characterized in that, The wall (6) of the walls (5, 6, 7, 8) of the tubular body (2) has a through groove (22) adapted to accommodate the partition member (23), which is welded to the wall (5, 6, 7, 8) of the tubular body (2) of the gas manifold by self-fusion welding, wherein the welding is selected as laser welding or arc welding, gas welding, plasma welding, TIG welding, MIG welding or MAG welding.
7. The gas manifold according to claim 6, characterized in that, The separating member (23) is welded along the through groove (22).
8. The gas manifold according to claim 6, characterized in that, Inside the internal cavity (9), in each wall (5, 7, 8) that defines the cavity except for the wall where the through groove (22) is provided, there are recesses (305, 307, 308), each recess (305, 307, 308) defining a seat (30) for the partition member, and the partition member is welded in the seat (30) by autofusion welding.
9. The gas manifold according to claim 6, characterized in that, The nozzles (11) of the burner are spaced apart by a distance equal to or greater than 10 mm.