Repair method of gas generator sheet sealing structure

Abstract

The present invention provides a method for repairing a thin-film sealing structure of a gas generator, comprising the following steps: grinding and removing the locating pin, using protective tape for comprehensive protection during grinding; cleaning debris by using a cleaning pin smaller than the size of the locating pin and wrapped with a cloth strip to insert into the pin hole of the locating pin for cleaning, and then blowing air into the pin hole to clean; marking the installation position by first marking the installation position of the thin-film sealing plate and then removing the old thin-film sealing plate; determining the specifications of the locating pin; welding the locating pin: selecting a suitable welding wire based on the material determination results of the locating pin, installing a new thin-film sealing plate and its spare parts at the marked position, and then welding the tail end of the locating pin to the thin-film sealing ring; and inspecting and completing the installation. Using the repair method of the present invention, the locating pin and the thin-film sealing plate are removed by fine grinding at the top of the locating pin to ensure that the thin-film seal can swing freely, meeting the manual requirements of the gas generator.

Description

Technical Field

[0001] The invention relates to the technical field of replacing a thin-sheet sealing plate of a gas generator, and in particular to a method for repairing a thin-sheet sealing structure of a gas generator. Background Art

[0002] The gas generator's lamella seal, located behind the liner of the worm gear's midframe, seals the high-pressure compensating gas within the worm gear's midframe, preventing it from entering the power turbine's airflow path and affecting its operation and sealing effectiveness. This high-pressure compensating gas seal is found on the LM2500+ gas generator.

[0003] After prolonged operation or when operating conditions change, the vibration of the gas generator and the pressure changes across the front and rear of the lamellae seal cause the lamellae seal to swing back and forth. This causes friction between the lamellae seal, the locating pins, and the turbine's first-stage guide vane support, leading to wear. Severe wear can damage and even cause the lamellae seal and locating pins to fall off, posing a safety hazard to the unit. Therefore, the worn lamellae seal and locating pins must be replaced.

[0004] At present, foreign manufacturers do not provide repair technology for the replacement of thin-sheet sealing plates and positioning pins. They can only be packaged and sent to foreign manufacturers for replacement and repair. The repair cycle is long, with a total cycle of up to 90 days, and the transportation and repair costs are high. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: how to realize the replacement and repair of the thin-sheet sealing plate of the gas generator.

[0006] The technical solution of the present invention to solve the above technical problems is as follows:

[0007] The present invention provides a method for repairing a thin-film sealing structure of a gas generator, wherein the thin-film sealing structure of the gas generator comprises a rotating worm gear middle frame, a thin-film sealing ring arranged at an outer ring edge of the worm gear middle frame, and a first-stage guide vane support cylinder arranged at an outer ring edge of the thin-film sealing ring; a thin-film sealing plate is connected to a side of the thin-film sealing ring facing the first-stage guide vane support cylinder via a welded positioning pin; an annular power turbine airflow channel is provided on the first-stage guide vane support cylinder surrounding the worm gear middle frame; a wall plate of the power turbine airflow channel facing the worm gear middle frame contacts and seals the thin-film sealing plate; a spring is sleeved on the positioning pin, one end of the spring abuts against the thin-film sealing plate, so that the thin-film sealing plate is closely attached to the wall plate of the power turbine airflow channel facing the worm gear middle frame;

[0008] The invention is characterized in that the repair method comprises the following steps:

[0009] S1: Grind the weld scar formed by welding the locating pin and the thin sealing ring and remove the locating pin. Use protective tape to seal the gap around the power turbine airflow channel for protection during grinding.

[0010] S2: Clean debris. Wrap a cleaning pin smaller than the locating pin with a cloth and insert it into the locating pin hole for cleaning. Then, blow air into the hole and use a pneumatic vacuum to clean metal debris on the worm gear frame before removing the protective tape.

[0011] S3: Mark the installation position of the lamellae sealing plate on the lamellae sealing ring and the first-stage guide vane support cylinder, then remove the old lamellae sealing plate and count the number of lamellae sealing plates, positioning pins and springs removed.

[0012] S4: Determine the specifications of the positioning pin: Measure the pin hole after the positioning pin is removed to confirm that the pin hole has not been deformed, and select a positioning pin that is suitable for the pin hole;

[0013] S5: Welding the positioning pin: Select the appropriate welding wire according to the positioning pin material test results, install the new sheet sealing plate and its spare parts at the marked position, and weld the tail end of the positioning pin to the sheet sealing ring;

[0014] S6: Check and complete the installation: Perform acid etching and fluorescence inspection on the weld scar area where the tail end of the positioning pin is welded to the thin-sheet sealing ring, and complete the repair after confirming that there are no defects.

[0015] On the basis of the above technical solution, the present invention can also be improved as follows.

[0016] Furthermore, the step of grinding and removing the locating pin also includes: grinding a 0.2mm wide annular groove at the welding connection between the top end of the locating pin and the thin sheet sealing ring to separate the top end of the locating pin from the thin sheet sealing ring.

[0017] This makes it easy to disassemble and install the thin-sheet sealing plate and fully protect the bearing chamber to prevent metal debris from entering the worm gear frame.

[0018] Furthermore, the step of grinding and removing the positioning pin further includes: partially grinding the weld scar at the tail of the positioning pin, and retaining a portion of the weld scar joint on the thin-sheet sealing ring;

[0019] The specific steps for welding the locating pin are as follows: select the appropriate welding wire according to the material measurement results of the locating pin, install the new thin-sheet sealing plate and its spare parts at the marked position, and then weld the tail end of the locating pin to the weld scar joint retained on the thin-sheet sealing ring.

[0020] On the premise of fully ensuring the remaining length of the locating pin, the thin-sheet sealing plate is removed at the top by fine grinding, so as to facilitate subsequent welding and fixation on the basis of the original locating pin; so as to ensure that the thin-sheet sealing plate after welding can swing back and forth normally along the radial direction of the thin-sheet sealing ring.

[0021] After installing a new thin-film sealing plate and its spare parts at the marked position, the specific steps for welding the tail end of the locating pin to the thin-film sealing ring are as follows: install a new thin-film sealing plate at the marked position, and put the spring on the locating pin, with one end of the spring resting on the thin-film sealing plate, so that the thin-film sealing plate is close to the wall panel of the power turbine airflow channel facing the worm gear middle frame side, and then weld the tail end of the locating pin to the thin-film sealing ring.

[0022] Furthermore, the gas generator is a LM2500+ model gas generator.

[0023] The beneficial effects of the present invention are:

[0024] The repair method of this invention removes the locating pin and the thin-plate seal plate by finely grinding the top of the locating pin, facilitating subsequent welding and securing of the thin-plate seal plate to the original locating pin. The weld scar at the tail of the locating pin is partially ground away, preserving the partial joint on the thin-plate seal ring. The tail of the locating pin is then welded to the thin-plate seal ring, ensuring the thin-plate seal can swing freely, meeting the gas generator manual requirements. Furthermore, comprehensive protection with protective tape and debris cleaning prevent metal debris from entering the interior of the midframe housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the gas generator sheet sealing structure of the present invention.

[0026] Figure 2 Schematic diagram of the installation structure of the thin-sheet sealing plate.

[0027] Figure 3 Schematic diagram of the flow direction of high-pressure compensation gas sealed by the thin-film sealing structure.

[0028] In the accompanying drawings, the technical features represented by the reference numerals are as follows:

[0029] 1-worm gear middle frame; 2-power turbine air flow channel; 3-thin-plate sealing plate; 4-locating pin; 5-first-stage guide vane support tube; 6-thin-plate sealing ring; 7-spring. DETAILED DESCRIPTION

[0030] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0031] The present invention refers to Figure 1-3 .

[0032] The present invention provides a method for repairing a thin-film sealing structure of a gas generator, wherein the thin-film sealing structure of the gas generator includes a rotating worm gear middle frame 1, a thin-film sealing ring 6 arranged at the outer ring edge of the worm gear middle frame 1, and a first-stage guide vane support tube 5 arranged at the outer ring edge of the thin-film sealing ring 6; a thin-film sealing plate 3 is connected to the side of the thin-film sealing ring 6 facing the first-stage guide vane support tube 5 via a welded positioning pin 4; an annular power turbine airflow channel 2 is provided on the first-stage guide vane support tube 5 surrounding the worm gear middle frame 1; a wall panel of the power turbine airflow channel 2 facing the worm gear middle frame 1 contacts and seals the thin-film sealing plate 3; a spring 7 is sleeved on the positioning pin 4, one end of the spring 7 abuts against the thin-film sealing plate 3, so that the thin-film sealing plate 3 is closely attached to the wall panel of the power turbine airflow channel 2 facing the worm gear middle frame 1;

[0033] The invention is characterized in that the repair method comprises the following steps:

[0034] S1: Grind the weld scar formed by welding the positioning pin 4 and the thin-sheet sealing ring 6 and remove the positioning pin 4. During grinding, use protective tape to seal the gap around the power turbine airflow channel 2 for protection;

[0035] Note: The purpose of using protective tape for comprehensive protection is to prevent metal debris from entering the interior of the midframe housing. Gaps around the turbine airflow channel 2, such as the gap between the turbine airflow channel 2 and the thin-film sealing plate 3, and the gap between the thin-film sealing plate 3 and the thin-film sealing ring 6.

[0036] Furthermore, the step of grinding and removing the positioning pin 4 also includes: grinding a 0.2 mm wide annular groove at the welding connection between the top end of the positioning pin 4 and the thin sheet sealing ring 6 to separate the top end of the positioning pin 4 from the thin sheet sealing ring 6.

[0037] This facilitates the disassembly and installation of the sheet sealing plate 3 and provides comprehensive protection for the bearing chamber to prevent metal debris from entering the interior of the worm gear middle frame 1.

[0038] Furthermore, the step of grinding and removing the positioning pin 4 further includes: partially grinding the weld scar at the tail of the positioning pin 4, and retaining a portion of the weld scar joint on the thin-sheet sealing ring 6;

[0039] The specific steps of welding the locating pin 4 are: select a suitable welding wire according to the material measurement results of the locating pin 4, install a new thin-sheet sealing plate 3 and its spare parts at the marked position, and then weld and fix the tail end of the locating pin 4 to the partial weld scar joint retained on the thin-sheet sealing ring 6.

[0040] Note: The purpose of retaining some weld joints on the sheet sealing ring 6 is to ensure that the end of the positioning pin 4 contacts the sheet sealing ring 6 to facilitate welding.

[0041] On the premise of fully ensuring the remaining length of the positioning pin 4, the thin-film sealing plate 3 is removed at the top by fine grinding, so as to facilitate subsequent welding and fixation on the basis of the original positioning pin 4; so as to ensure that the thin-film sealing plate 3 after welding can swing back and forth normally along the radial direction of the thin-film sealing ring 6.

[0042] S2: Clean debris. Wrap a cloth strip around a cleaning pin that is smaller than the size of the positioning pin 4 and insert it into the pin hole of the positioning pin 4 for cleaning. Then, blow air into the pin hole to clean it. Use a pneumatic vacuum cleaner to clean the metal debris on the worm gear middle frame 1, and then remove the protective tape.

[0043] Note: The rear end of the positioning pin 4 is connected to the thin sheet sealing ring 6 by welding. In order to facilitate the subsequent welding of the positioning pin 4, the weld scar at the tail of the positioning pin 4 is partially polished to retain part of the joint on the thin sheet sealing ring 6.

[0044] S3: Mark the installation position of the thin-film sealing plate 3 on the thin-film sealing ring 6 and the first-stage guide vane support cylinder 5, then remove the old thin-film sealing plate 3, and count the number of removed thin-film sealing plates 3, positioning pins 4, and springs 7;

[0045] Note: Before installation, record the entire installation structure and create a blueprint documenting the entire structure to ensure that the new sheet seal 3 is installed in its original position. Count the old sheet seal 3, locating pins 4, and springs 7 as you remove them to ensure that no parts are lost or remain in the housing. When disassembling the sheet seal 3, mark the radial and circumferential position and orientation of the 48 original seals to ensure they are reinstalled in their original positions.

[0046] S4: Determine the specifications of the positioning pin 4: Measure the pin hole after the positioning pin 4 is removed to confirm that the pin hole has not been deformed, and select a positioning pin 4 that is suitable for the pin hole;

[0047] Note: Select the locating pin 4 that fits the pin hole and measure it to ensure that the error between the pin hole and the locating pin 4 is within the standard range to ensure a good overall installation effect.

[0048] S5: Welding the positioning pin 4: Select appropriate welding wire according to the material determination result of the positioning pin 4, install the new sheet sealing plate 3 and its spare parts at the marked position, and weld the tail end of the positioning pin 4 to the sheet sealing ring 6;

[0049] Note: Weld the tail end of the positioning pin 4 to the sheet sealing ring 6 to ensure that the sheet sealing plate 3 can swing back and forth normally along the radial direction of the sheet sealing ring 6 after welding. The preferred welding wire brand is HS188 (AMS5801).

[0050] After installing a new thin-film sealing plate 3 and its spare parts at the marked position, the steps for welding and fixing the tail end of the locating pin 4 to the thin-film sealing ring 6 are as follows: install a new thin-film sealing plate 3 at the marked position, and put the spring 7 on the locating pin 4, with one end of the spring 7 resting on the thin-film sealing plate 3, so that the thin-film sealing plate 3 is close to the wall panel of the power turbine airflow channel 2 facing the worm gear middle frame 1, and then, weld and fix the tail end of the locating pin 4 to the thin-film sealing ring 6.

[0051] S6: Check and complete the installation: Perform acid etching and fluorescence inspection on the weld scar area where the tail end of the positioning pin 4 is welded to the thin-sheet sealing ring 6, and complete the repair after confirming that there are no defects.

[0052] Note: Acid etching and fluorescence inspection are performed on the weld scar area to ensure that the welded positioning pin 4 meets the welding standards. Repairs are completed after inspection and no defects are found.

[0053] Furthermore, the gas generator is a LM2500+ model gas generator.

[0054] Figure 3 The direction of the arrow is the flow direction of the high-pressure compensation gas. The function of the gas generator thin-film sealing structure is to seal the high-pressure compensation gas inside the worm gear frame 1 to prevent the high-pressure gas from entering the power turbine airflow channel 2 and affecting its operating state and sealing effect.

[0055] In summary, the repair method of the present invention removes the locating pin 4 and the thin-film seal plate 3 by finely grinding the top of the locating pin 4, facilitating subsequent welding and securing of the thin-film seal plate 3 to the original locating pin 4. The weld scar at the tail of the locating pin 4 is partially polished, preserving the partial joint on the thin-film seal ring 6. The tail of the locating pin 4 is then welded to the thin-film seal ring 6, ensuring the free swing of the thin-film seal, which meets the manual requirements of the gas generator. Furthermore, comprehensive protection with protective tape and cleaning of debris prevent metal debris from entering the interior of the midframe housing.

[0056] In the description of the present invention, it should be understood that if there appear descriptive terms indicating orientation, direction or positional relationship, such as: "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the orientation or positional relationship indicated in this specification is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of understanding the present invention and simplifying the description, and does not indicate or imply that the part, element or whole referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0057] In addition, if there are order description terms, such as "first", "second", etc., their purpose in this specification is to facilitate understanding or simplify the description. For example, in order to distinguish multiple technical features with the same type or function, but they have to be mentioned separately, this specification may use prefix or suffix order description terms to distinguish them. Therefore, it cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0058] In the present invention, if terms describing the relative functional relationship of structures are used, such as "install", "connect", "connect", "fix", etc., they should be understood in a broad sense unless otherwise clearly specified and limited. For example, "install", "connect", "connect", etc. can be fixed connections, detachable connections, or integrated; can be mechanical connections or electrical connections; can be direct connections or indirect connections through an intermediate medium, can be internal connections between two elements or an interactive relationship between two elements; "fix" can be an integrated fixation or a detachable fixation through fasteners; can be a direct fixation or a fixation through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above-mentioned descriptive terms in the present invention can be understood according to the specific circumstances, the context, the coherence of the preceding and following texts, etc.

[0059] In the present invention, if descriptive terms with subsidiary or connecting meanings appear, for example, a first feature is "on" or "below" a second feature, unless otherwise clearly specified and limited, they should not be understood in a restrictive manner. For example, "on" or "below" can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. For those skilled in the art, the specific meanings of the above descriptive terms in the present invention can be understood based on the specific circumstances, the context, the coherence of the preceding and following texts, etc.

[0060] Furthermore, when a first feature is “above,” “above,” or “above” a second feature, it may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. When a first feature is “below,” “below,” or “below” a second feature, it may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0061] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments, examples and features of different embodiments and examples described in this specification, unless there is any contradiction, and these combinations or combinations should all fall within the scope of the present invention.

[0062] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limiting the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of information available through public channels and in combination with the technical inspiration provided by the present application documents.

Claims

1. A method for repairing a thin-film sealing structure of a gas generator, wherein the thin-film sealing structure of the gas generator comprises a rotating worm wheel middle frame (1), a thin-film sealing ring (6) arranged at the outer ring edge of the worm wheel middle frame (1), and a first-stage guide vane support cylinder (5) arranged at the outer ring edge of the thin-film sealing ring (6); a thin-film sealing plate (3) is connected to the side of the thin-film sealing ring (6) facing the first-stage guide vane support cylinder (5) through a welded positioning pin (4); an annular power turbine airflow channel (2) is provided on the first-stage guide vane support cylinder (5) around the worm wheel middle frame (1); a wall plate of the power turbine airflow channel (2) facing the worm wheel middle frame (1) contacts and seals the thin-film sealing plate (3); a spring (7) is sleeved on the positioning pin (4), one end of the spring (7) abuts against the thin-film sealing plate (3), so that the thin-film sealing plate (3) is in close contact with the wall plate of the power turbine airflow channel (2) facing the worm wheel middle frame (1); Its characteristics are: The repair method includes the following steps: S1: Grind the weld scar formed by welding the positioning pin (4) and the thin-sheet sealing ring (6) and remove the positioning pin (4). During the grinding, use protective tape to seal the gap around the power turbine airflow channel (2) for protection; S2: Clean debris by wrapping a cleaning pin smaller than the size of the positioning pin (4) with a cloth strip and inserting it into the pin hole of the positioning pin (4) for cleaning. Then, blow air into the pin hole to clean it. Use a pneumatic vacuum cleaner to clean the metal debris on the worm gear middle frame (1), and then remove the protective tape. S3: Mark the installation position of the thin-sheet sealing plate (3) on the thin-sheet sealing ring (6) and the first-stage guide vane support cylinder (5), then remove the old thin-sheet sealing plate (3), and count the number of removed thin-sheet sealing plates (3), positioning pins (4), and springs (7); S4: Determine the specifications of the positioning pin (4): Measure the pin hole from which the positioning pin (4) is removed to confirm that the pin hole has not been deformed, and select a positioning pin (4) that is suitable for the pin hole; S5: Welding the positioning pin (4): Select appropriate welding wire according to the material determination result of the positioning pin (4), install the new sheet sealing plate (3) and its spare parts at the marked position, and then weld the tail end of the positioning pin (4) to the sheet sealing ring (6); S6: Check and complete the installation: Acid-etch and fluorescent-check the weld scar area where the tail end of the positioning pin (4) is welded to the thin-sheet sealing ring (6), and the repair is completed after confirming that there are no defects.

2. The method for repairing a gas generator sheet sealing structure according to claim 1, characterized in that: The step of grinding and removing the positioning pin (4) also includes: grinding a 0.2mm wide annular groove at the welding connection between the top end of the positioning pin (4) and the thin sheet sealing ring (6) to separate the top end of the positioning pin (4) from the thin sheet sealing ring (6).

3. The method for repairing the gas generator sheet sealing structure according to claim 2, characterized in that: The step of grinding and removing the positioning pin (4) further includes: partially grinding the weld scar at the tail of the positioning pin (4) and retaining a portion of the weld scar joint on the thin-sheet sealing ring (6); The specific steps of welding the positioning pin (4) are as follows: selecting a suitable welding wire according to the material determination result of the positioning pin (4), installing a new thin-sheet sealing plate (3) and its spare parts at the marked position, and then welding the tail end of the positioning pin (4) to the weld scar joint retained on the thin-sheet sealing ring (6) to fix it.

4. The method for repairing a gas generator sheet sealing structure according to claim 1, characterized in that: After installing a new sheet sealing plate (3) and its spare parts at the marked position, the steps of welding and fixing the tail end of the positioning pin (4) to the sheet sealing ring (6) are specifically as follows: installing a new sheet sealing plate (3) at the marked position, and sleeve the spring (7) on the positioning pin (4), with one end of the spring (7) resting on the sheet sealing plate (3), so that the sheet sealing plate (3) is closely attached to the wall panel of the power turbine airflow channel (2) facing the worm gear middle frame (1), and then welding and fixing the tail end of the positioning pin (4) to the sheet sealing ring (6).

5. The method for repairing a gas generator sheet sealing structure according to claim 1, characterized in that: The gas generator is a LM2500+ model gas generator.

Images