Disassembling method of aero-engine fuel control module sealing device

Abstract

The invention discloses a disassembling method of an aero-engine fuel control module sealing device. The disassembling method comprises the following steps that a low-pressure turbine pressing ring is screwed out of an oil pump end and then pulled out of a low-pressure turbine pressing plate; taking out the graphite ring; a spline shaft of the main transmission shaft is fixed through a wrench so as to fix the driving gear, a hexagon nut of the low-pressure turbine is rotated, and the low-pressure turbine is decomposed from the driving gear. By adopting the method, the crushing damage and sealing rubber ring damage conditions can be reduced, and the decomposition efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of sealing device disassembly, and in particular relates to a method for disassembling a sealing device of an aircraft engine fuel control module. Background Art

[0002] The aircraft engine fuel control system provides the engine with clean fuel of a certain pressure and flow rate, and controls the engine power to ensure the full implementation of the engine control plan, maximize its performance under the premise of safety and reliability, and protect the engine from exceeding its usage limits. When the engine has an excessive oil leakage fault during the test run, the engine fuel control system needs to be troubleshooted. In this control system, the fuel control module serves as the actual actuator, and is composed of two parts: a regulator and an oil pump. The oil pump part includes components such as a low-pressure turbine 71, a high-pressure gear, a fuel filter, and an oil filter bypass valve. A graphite sealing device is also provided at the low-pressure turbine to prevent fuel from flowing out of the oil pump, such as Figure 1 Therefore, to solve the problem of excessive oil leakage, the graphite ring 72 and the low-pressure turbine 71 need to be disassembled, and the two sealing contact surfaces need to be repaired and tested for sealing properties.

[0003] The current method of disassembling the sealing device is: first separate the regulator part and the oil pump part, then find the main drive shaft equipped with the low-pressure turbine 71 by disassembling the upper and lower end bearings, the driving gear 73 and other components, and finally manually force the gear to unscrew the low-pressure turbine.

[0004] However, there are two problems with the existing method: 1. During the disassembly process, excessive torque will cause serious compression damage to the gear tooth surface, which will seriously affect the torque transmission of the driving gear while generating excess material. The damage rate is as high as 60%, which greatly affects the test pass rate and thus the delivery progress; 2. The disassembly process involves the disassembly of multiple components. There is currently no corresponding standard in China for the original assembly parameters between the components, and there is also a risk of damage to the sealing rubber ring; 3. Long decomposition time. The average decomposition time of the existing method is about 180 minutes, and the highest decomposition time even exceeds 240 minutes. Summary of the invention

[0005] In order to solve the problems of existing sealing device disassembly methods causing compression damage to gear tooth surfaces, damage to sealing rubber rings, and long disassembly time, the present invention proposes a disassembly method for a sealing device of an aircraft engine fuel control module, which can reduce compression damage and damage to the sealing rubber ring and improve disassembly efficiency.

[0006] The objective of the present invention is achieved through the following technical solutions: The present invention discloses a method for disassembling a sealing device of an aircraft engine fuel control module, comprising the following steps: Unscrew the low-pressure turbine pressure ring from the oil pump end and then pull out the low-pressure turbine pressure plate; Remove the graphite ring; Use a wrench to fix the spline shaft of the main drive shaft to fix the driving gear, turn the hexagonal nut of the low-pressure turbine, and disassemble the low-pressure turbine from the driving gear.

[0007] Furthermore, the wrench includes a spline sleeve tooth matching the spline shaft, a fixed handle, and a wrench connecting arm connected between the spline sleeve tooth and the fixed handle.

[0008] Furthermore, the hexagonal nut for rotating the low-pressure turbine is: After installing the hexagonal rocker arm on the hexagonal nut, the hexagonal rocker arm is rotated to rotate the hexagonal nut of the low-pressure turbine.

[0009] Furthermore, the hexagonal rocker arm includes a rocker arm, a hexagonal socket gear and a rocker arm connecting arm connected between the rocker arm and the hexagonal socket gear.

[0010] Furthermore, the minimum inner diameter of the hexagonal socket teeth is greater than the outer diameter of the spline socket teeth.

[0011] The beneficial effects of the present invention are: 1. The present invention fixes the driving gear by a wrench, and the force point of the wrench is at the spline of the main transmission shaft. The spline has a large contact area, is not easy to damage the tooth surface of the main transmission shaft, and reduces the damage to the sealing rubber ring.

[0012] 2. The method of this scheme has high decomposition efficiency and short time consumption, and the average decomposition time can be shortened to less than 30 minutes.

[0013] 3. This solution only disassembles a few parts in a targeted manner, greatly reducing the number of sealing rubber rings involved and greatly reducing the risk of damage to the overall sealing rubber ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 It is a schematic diagram of the structure of graphite ring and low-pressure turbine; Figure 2 It is a schematic diagram of the hexagonal rocker arm structure; Figure 3is a schematic diagram of the wrench structure; Figure 4 This is a schematic diagram of the use of the hexagonal rocker arm and wrench. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0017] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0019] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0020] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use, or the positions or positional relationships commonly understood by those skilled in the art, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] The inventor has designed a method for disassembling the sealing device of the fuel control module of an aircraft engine by studying the installation characteristics of the external structure of the oil pump part of the fuel control module, the low-pressure turbine structure and the graphite sealing device structure, which solves the problem that the original method of disassembly is time-consuming and inefficient, especially causing surface damage to other related components. In order to prevent damage to related components, reduce the disassembly time of the sealing device and improve efficiency, when the regulator and the oil pump are not separated, the method directly disassembles the low-pressure turbine pressure plate and the pressure ring from the oil pump end, and then uses a special disassembly device to remove the graphite sealing device and the low-pressure turbine without damage. Specifically, the method includes steps S01 to S03. It should be noted that the step identification in this scheme is only for the convenience of explaining the method, and does not constitute a limitation on the order of precedence. The order of each step is based on its language description and the order of each signal.

[0023] Step S01, unscrew the low-pressure turbine pressure ring from the oil pump end and then pull out the low-pressure turbine pressure plate.

[0024] Step S02: Take out the graphite ring.

[0025] Take out the graphite ring to avoid being crushed or falling off during the decomposition process.

[0026] Step S03: Use a wrench to fix the spline shaft of the main transmission shaft to fix the driving gear, turn the hexagonal nut of the low-pressure turbine, and disassemble the low-pressure turbine from the driving gear.

[0027] This step uses a wrench and an internal hexagon rocker arm. The structures of the internal hexagon rocker arm and the wrench are detailed in Figure 2 , 3 shown.

[0028] like Figure 2 As shown, the hexagonal rocker arm includes a rocker arm 1, a hexagonal socket gear 3 and a rocker arm connecting arm 2 connected between the rocker arm 1 and the hexagonal socket gear 3.

[0029] like Figure 3 As shown, the wrench includes a spline sleeve tooth 4 matched with the spline shaft, a fixed handle 6 and a wrench connecting arm 5 connected between the spline sleeve tooth 4 and the fixed handle 6 .

[0030] The minimum inner diameter of the hexagon socket teeth 3 is greater than the outer diameter of the spline socket teeth 4. Figure 4 As shown, the hexagon socket teeth 3 can be placed in the spline socket teeth 4 when in use.

[0031] Specifically, first, the spline sleeve teeth 4 of the wrench are sleeved on the spline shaft of the main transmission shaft, and the fixing handle 6 is stabilized to prevent the main transmission shaft from rotating and thus fix the driving gear; then, the hexagonal rocker arm is installed on the hexagonal nut and the hexagonal rocker arm is rotated to rotate the hexagonal nut of the low-pressure turbine, that is, the hexagonal sleeve teeth 3 are sleeved on the hexagonal nut of the low-pressure turbine, and the low-pressure turbine is connected to the driving gear through a thread, and the rocker handle 1 of the hexagonal rocker arm is rotated to disassemble the low-pressure turbine from the driving gear.

[0032] By adopting the above method, the wrench is connected to the spline sleeve teeth through the connecting arm, so that the force point of the spline sleeve teeth is at the spline of the main drive shaft, and it is fixed by the internal and external splines. The spline contact area is large and it is not easy to damage the tooth surface of the main drive shaft. The internal hexagonal sleeve teeth 3 of the internal hexagonal rocker arm penetrate into the hexagonal nut of the oil pump sleeve on the low-pressure turbine. The low-pressure turbine is an integrated structure. By shaking the crank handle of the internal hexagonal rocker arm, the torque can be transmitted to the entire low-pressure turbine, and the threaded low-pressure turbine can be decomposed from the driving gear. Because the main drive shaft spline is above the low-pressure turbine, the wrench acts on the upper part of the internal hexagonal rocker arm. Within this height difference range, the rotational movement of the internal hexagonal rocker arm is not affected by the spline wrench.

[0033] By adopting the above method, the average decomposition time of the graphite sealing device was reduced to less than 30 minutes, and the damage rate of related components was reduced to 0.

[0034] After using the tooling, only a few parts can be disassembled in a targeted manner, the number of sealing rubber rings involved is greatly reduced, and the risk of damage to the overall sealing rubber ring is greatly reduced.

[0035] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A method for disassembling a sealing device of an aircraft engine fuel control module, characterized in that: The following steps are involved: Unscrew the low-pressure turbine pressure ring from the oil pump end and then pull out the low-pressure turbine pressure plate; Remove the graphite ring; Use a wrench to fix the spline shaft of the main drive shaft to fix the driving gear, turn the hexagonal nut of the low-pressure turbine, and disassemble the low-pressure turbine from the driving gear.

2. The method for disassembling the sealing device of the fuel control module of an aircraft engine according to claim 1, characterized in that: The wrench comprises a spline sleeve tooth (4) matched with the spline shaft, a fixed handle (6), and a wrench connecting arm (5) connected between the spline sleeve tooth (4) and the fixed handle (6).

3. The method for disassembling the sealing device of the fuel control module of an aircraft engine according to claim 2, characterized in that: The hexagonal nut for rotating the low-pressure turbine is: After installing the hexagonal rocker arm on the hexagonal nut, the hexagonal rocker arm is rotated to rotate the hexagonal nut of the low-pressure turbine.

4. A method for disassembling a sealing device of an aircraft engine fuel control module according to claim 3, characterized in that: The hexagonal rocker arm comprises a rocker arm (1), a hexagonal sleeve tooth (3), and a rocker arm connecting arm (2) connected between the rocker arm (1) and the hexagonal sleeve tooth (3).

5. A method for disassembling a sealing device of an aircraft engine fuel control module according to claim 4, characterized in that: The minimum inner diameter of the hexagonal socket teeth (3) is greater than the outer diameter of the spline socket teeth (4).

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