Method for securing a spring washer to a combustion chamber housing

Abstract

The invention relates to a method for securing a spring washer (05) to a combustion chamber housing (02). The combustion chamber housing (02) has a cylindrical receiving portion (03) at least at the downstream end. The spring washer (05) comprises a cylindrical fastening portion (06) and a plurality of spring tabs (07) distributed over the circumference. First, a solder material is applied to the inner face of the fastening portion (06). Then, the spring washer (05) is joined onto the combustion chamber housing (02) such that the fastening portion (06) is located on the receiving portion (03). A connection of the fastening portion (06) to the receiving portion (03) is achieved by heating the fastening portion (06) and / or the receiving portion (03). According to the invention, the spring tabs (07) are cooled at the same time.

Description

Description TITLE L Method for attaching a spring ring to a combustion chamber housing TECHNICAL BOROUGH

[0001] The invention relates to a method for attaching a spring ring to a combustion chamber housing. BACK ROUND

[0002] In gas turbines, it is common practice to arrange a transition channel to the expansion turbine following the combustion chamber casing. The combustion chamber casing is inserted section by section into the transition channel, with elastically deformable spring tabs often used in the connection between the combustion chamber casing and the transition channel; these tabs are attached to the combustion chamber casing at a distribution around its circumference.

[0003] The spring tabs are usually attached to the combustion chamber housing individually or in groups by welding.

[0004] The spring tabs are subject to high dynamic and thermal stress, so they usually need to be repaired or replaced during the service life of the gas turbine. This involves mechanically removing them and then welding on new parts.

[0005] One disadvantage is the effort required to weld on the spring tabs. Another is that the welding process causes deformation of the combustion chamber housing, which in turn negatively affects its service life. SUMMARY OF THE INVENTION

[0006] The task is therefore to provide an improved repair process.

[0007] The problem is solved by a method according to the invention as described in claim 1. Advantageous embodiments are the subject of the dependent claims.

[0008] The method serves to attach a spring ring to a combustion chamber housing. The combustion chamber housing has a cylindrical receiving section at least at the downstream end. The spring ring (05) comprises a cylindrical mounting section and a plurality of spring tabs distributed around its circumference.

[0009] First, a soldering compound is applied to the inside of the mounting section. The spring ring is then fitted onto the combustion chamber housing so that the mounting section is positioned on the receiving section. A bond is created between the mounting section and / or the receiving section by heating them. The spring tabs are simultaneously cooled during this process. DESCRIPTION OF THE INVENTION

[0010] This method is used to attach a spring ring to a combustion chamber housing. The shape of the combustion chamber housing is initially irrelevant. At a minimum, it is required that it has a cylindrical receiving section at the downstream end. The spring ring comprises, as its essential elements, a cylindrical mounting section and a plurality of spring tabs.

[0011] Preferably, the inner diameter of the mounting section corresponds substantially to the outer diameter of the receiving section. Considering the intended mounting and fastening method, a A slight difference between the inner diameter of the mounting section and the outer diameter of the receiving section may be advantageous.

[0012] The design of the spring tabs is initially irrelevant for the method. With regard to their function as a subsequent connection between the combustion chamber housing and a transition section, these preferably extend in the flow direction with an increasing distance from the central axis of the spring ring upstream. In order to ensure the elastic properties of the spring tabs, they are separated from each other by a gap and are only connected on the side of the fastening section.

[0013] For the fastening according to the invention, it is necessary to apply a solder material to the inside of the fastening section. How the application is carried out is initially irrelevant. At the very least, it should be applied evenly distributed around the circumference.

[0014] The solder material is particularly advantageously applied by weld overlay, resulting in a coating-like appearance. In the next step, the spring ring is mounted onto the combustion chamber housing, so that the mounting section surrounds the receiving section. It can be advantageous to preheat the spring ring, or at least the mounting section, before joining. Alternatively or additionally, the combustion chamber housing, or at least the receiving section, can be cooled. Care must be taken to ensure that the temperature of the spring ring is not too high, so that the solder material remains in the applied area and the spring tabs are not thermally damaged. At the very least, the temperature difference leads to different expansion rates of the components, thus simplifying the joining process.

[0017] After the spring ring is positioned in the intended location, the fastening section and / or the receiving section is heated, so that at least part of the solder material melts.

[0018] After the assembly has cooled down, a firm connection between the spring ring and the combustion chamber housing is then present.

[0019] The advantageous method for attaching the spring ring prevents thermal deformation of the combustion chamber housing and the spring ring itself. This results in a better fit of the assembly during subsequent use in the transition channel and thus a longer service life.

[0020] It is advantageously provided that the heating is inductive.

[0021] Furthermore, it is advantageously provided that active cooling of the spring tabs is carried out simultaneously with the heating process, so that they are not thermally damaged and do not lose some of their elasticity. For this purpose, cooling air is directed to the spring tabs in a simple and advantageous manner.

[0022] For this purpose, a joining tool is used to a particularly advantageous extent, which is positioned over the spring ring and contains at least one induction coil. Care should be taken to ensure that the joining tool allows the cooling air to flow along the spring tabs, while shielding it from the fastening section. SHORT DESCRIPTION OF THE SIGNS

[0023] FIG 1 sketches an exemplary combustion chamber housing 02.

[0024] FIG 2 schematically sketches a spring ring 05 during the application of the solder material.

[0025] FIG 3 schematically outlines the process of attaching the spring ring 05 to the combustion chamber housing 01.

[0026] FIG 4 sketches a combustion chamber arrangement 01 with the combustion chamber housing 02 and the spring ring 05. DESCRIPTION OF THE EXECUTION FORM EN

[0027] Figure 1 shows an example of a combustion chamber housing 02. This 02 has a cylindrical receiving section 03 at its downstream end.

[0028] Figure 2 shows an exemplary spring ring 05, which has a cylindrical fastening section 06 and a plurality of spring tabs 07 arranged around the circumference.

[0029] Furthermore, the application of the solder material to the inside of the fastening section 06 is schematically sketched.

[0030] Figure 3 shows the combustion chamber housing 02 with the spring ring 05 mounted on it, wherein the fastening section 06 of the spring ring 05 is surrounded by a joining tool 11. An induction coil for heating the fastening section 06 is arranged in the joining tool 11.

[0031] Figure 3 also shows a cooling air supply 12, which is provided for cooling the spring tabs 07. Preferably, the cooling air is shielded from the fastening section 06 and directed away from the joining tool 11.

[0032] Figure 4 shows the completed combustion chamber assembly 01 with the combustion chamber housing 02 and the spring ring 05 attached to it.

Claims

Claims 1. Method for attaching a spring washer (05) to a Combustion chamber housing (02), wherein the combustion chamber housing (02) has at least at its downstream end a cylindrical receiving section (03) and the spring ring (05) has a cylindrical mounting section (06) and a plurality of circumferentially distributed spring tabs (07); with the steps - Application of a solder material to the inside of the fastening section (06), - Fitting the spring ring (05) onto the combustion chamber housing (02) with the positioning of the mounting section (06) on the receiving section (03), - Heating of the fastening section (06) and / or the receiving section (03) while simultaneously cooling the spring tabs (07).

2. Method according to claim 1, wherein the solder material is applied by means of weld overlay.

3. Method according to claim 1 or 2, wherein at least the receiving section (03) of the combustion chamber housing (02) and / or the spring ring (05) and / or the solder material is based on a nickel-based alloy.

4. Method according to any one of claims 1 to 3, wherein the heating is carried out inductively.

5. Method according to any one of claims 1 to 4, wherein cooling is carried out by active air cooling.

6. Method according to one of claims 1 to 5, wherein a joining tool (11 ) is arranged on the spring ring (05) for heating and cooling, the joining tool (11 ) comprising an induction coil and cooling air guide. Method according to any one of claims 1 to 6, wherein the fastening section (06) is heated and / or the receiving section (03) is cooled before the spring ring (05) is fitted onto the combustion chamber housing (02).

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