A guiding structure for a borescope guiding wire and a borescope inspection method

Abstract

The present invention discloses a guiding structure for a borescope guiding wire and a borescope inspection method. The guiding structure includes a guiding tube, and the guiding tube includes: a straight tube portion; and a bent tube portion; the bent tube portion is located downstream of the straight tube portion and is connected to the straight tube portion, and the axis of the straight tube portion is arranged non-coincidentally with the extending direction of the outlet end of the bent tube portion. The beneficial effect of the present invention is that the guiding tube can guide the guiding wire to the measured point, without the need for the operator to keep holding it all the time, which plays a protective role for both the detection head and the inside of the engine and prevents collision damage.

Description

Technical Field

[0001] The present invention relates to a guiding tool for a borescope guiding wire, and more particularly to a guiding structure for a borescope guiding wire and a borescope inspection method. Background Art

[0002] In the field of aero-engines, after the aero-engine is assembled or undergoes stage-by-stage test runs, it is necessary to use a borescope device to perform auxiliary inspections through the "borescope hole" on the casing to observe whether there are damages to the internal components of the engine. Common borescope devices include a guiding wire, a detection head, and a display. The detection head is located at the front end of the guiding wire and is used to photograph the internal area of the engine casing. The guiding wire is used to transmit data, and the display shows the photographed area of the detection head.

[0003] Generally, it is necessary for the inspection personnel to insert the detection head deep into the "borescope hole" on the casing for inspection. The inner diameter of the "borescope hole" on the casing is much larger than the outer diameter of the detection head. During the whole process, the position of the "detection head" is completely manually controlled by the inspection personnel. When encountering a double-layer casing, it is difficult for the guiding wire of the detection head to penetrate. Being completely manually controlled by the inspection personnel, it is impossible to judge the depth of the guiding wire penetrating into the casing or the twisting direction. If it is necessary to accurately locate the fault point during the whole process, there are very high requirements for the operation accuracy of the operator. During the whole operation process, the personnel operating the "borescope guiding wire" need to always hold the "guiding wire" by hand and cannot perform other work, which is both laborious and prone to misoperation. During the test process, it is easy to damage the "detection head" of the borescope equipment and even cause damage to the engine. Summary of the Invention

[0004] The object of the present invention is to provide a guiding structure for a borescope guiding wire.

[0005] Another object of the present invention is to provide a borescope inspection method.

[0006] According to one aspect of the present invention, a guiding structure for a borescope guiding wire includes a guiding tube, and the guiding tube includes: a straight tube portion; and a bent tube portion; the bent tube portion is located downstream of the straight tube portion and is connected to the straight tube portion, and the axis of the straight tube portion is arranged non-coaxially with the extending direction of the outlet end of the bent tube portion.

[0007] In one or more specific embodiments of the guiding structure, a plane formed by the extending direction of the straight pipe portion and the extending direction of the bent pipe portion is defined as the first plane. The straight pipe portion has a fixed position so that the straight pipe portion is fixed to the casing at the fixed position. The guiding structure includes: a first guiding pipe, the bending direction of the first guiding pipe being located in a plane perpendicular to the first plane; the bent pipe portion of the first guiding pipe having a wavy extending section, the bending radius of the wave crest and wave trough of the wavy extending section being 2-5 times the outer diameter of the guiding pipe, and the bending angle of the wave crest and wave trough being 45°-170°; and / or a second guiding pipe, the bending direction of the second guiding pipe being located in the first plane, the bent pipe portion of the second guiding pipe having a second hook section, the included angle between the end and the starting end of the second hook section being 30°-80°, and the bending radius of the second hook section being 2-5 times the outer diameter of the guiding pipe; and / or a third guiding pipe, the bending direction of the third guiding pipe being located in the first plane, the bent pipe portion of the third guiding pipe having a third hook section, the included angle between the end and the starting end of the third hook section being 100°-170°, and the bending radius of the third hook section being 2-5 times the outer diameter of the guiding pipe.

[0008] In one or more specific embodiments of the guiding structure, the bent pipe portion of the second guiding pipe includes a straight pipe section, and the included angle between the straight pipe section and the straight pipe portion of the second guiding pipe is 45°-180°; the bent pipe portion of the third guiding pipe includes a straight pipe section, and the included angle between the straight pipe section and the straight pipe portion of the third guiding pipe is 45°-180°.

[0009] In one or more specific embodiments of the guiding structure, the fixed position further includes a handle. The handle is fixedly connected to the straight pipe portion, and the handle and the straight pipe portion define a positioning plane. The first plane of the first guiding pipe coincides with the positioning plane, the included angle between the first plane of the second guiding pipe and the positioning plane is 0-90°, and the included angle between the first plane of the third guiding pipe and the positioning plane is 0-90°.

[0010] In one or more specific embodiments of the guiding structure, the handle has an asymmetric structure on both sides, and has a first blind hole, a second blind hole, a rectangular side, and an arc side on both sides respectively.

[0011] In one or more specific embodiments of the guiding structure, the material of the guiding pipe is a thermoplastic material.

[0012] According to another aspect of the present invention, a borescope inspection method includes using the guide structure as described above, and the borescope inspection method includes: step A. for the inspection position being the root of the stator blade of the gas turbine engine or the area inside the rotor hub, the second guide tube of the guide structure is selected; for the inspection position being the rotor blade of the gas turbine engine or the end surface area of the rotor that needs to be viewed across the stage after passing through a farther borescope hole, the first guide tube of the guide structure is selected; for the inspection position being the circumferential blade area of the gas turbine engine, the third guide tube of the guide structure is selected; step B. extending the guide tube from the exploration hole of the casing until it is fixed to the casing, and the guide tube does not collide with the components inside the casing; step C. extending the guide wire and the detection head of the borescope into the guide tube until the detection head reaches the inspection position.

[0013] In one or more specific embodiments of the borescope inspection method, in step A, for inspection positions of turbine rotor blades of a gas turbine engine of different stages, the first guide tube of the guide structure is selected, and for inspection of rotor blades of the Nth stage, the extended length of the bent tube portion of the first guide tube is selected as a first length, and for inspection of rotor blades of the N+1th stage, the extended length of the bent tube portion of the first guide tube is selected as a second length, and the second length is greater than the first length.

[0014] In one or more specific embodiments of the borescope inspection method, the guide tube is made of thermoplastic material. In step B, if the guide tube collides with components inside the casing, the guide tube is heated and the structure of the bent tube portion is adjusted until there is no collision between the guide tube and components inside the casing.

[0015] In one or more specific embodiments of the borescope inspection method, the guide structure also includes a handle, and the handle and the straight tube portion define a positioning plane, the first plane of the first guide tube coincides with the positioning plane, the angle between the first plane of the second guide tube and the positioning plane is 0°-90°, and the angle between the first plane of the third guide tube and the positioning plane is 0°-90°. In step B, the guide tube is extended from the exploration hole of the receiver, and the guide structure is straightened by adjusting the position of the handle.

[0016] The beneficial effects of the present invention are:

[0017] The guide tube can guide the guide wire to the test point, so the operator does not need to hold it all the time and can do other work, saving physical energy and making it less likely to make operating errors, thus improving the detection efficiency. At the same time, it protects the detection head and the inside of the engine, preventing damage and saving detection costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above-mentioned and other features, properties and advantages of the present invention will become more apparent from the following description in conjunction with the accompanying drawings and embodiments, in which the same reference numerals always denote the same features. It should be noted that these drawings are only examples and are not drawn according to the condition of equal scale, and should not be used to limit the actual scope of protection required by the present invention, where:

[0019] Figure 1 Schematic diagram of a guiding structure of an embodiment;

[0020] Figure 2 Schematic diagram of a first guiding tube of an embodiment;

[0021] Figure 3 According to Figure 2 A - A cross-sectional view of the first guiding tube according to the schematic diagram;

[0022] Figure 4 Schematic diagram of a second guiding tube of an embodiment;

[0023] Figure 5 Top view of a second guiding tube of an embodiment;

[0024] Figure 6 According to Figure 5 B - B cross-sectional view of the second guiding tube according to the top view;

[0025] Figure 7 Schematic diagram of a third guiding tube of an embodiment;

[0026] Figure 8 Top view of a third guiding tube of an embodiment;

[0027] Figure 9 According to Figure 8 C - C cross-sectional view of the third guiding tube according to the top view;

[0028] Figure 10 Schematic diagram of the guiding structure of an embodiment in another direction;

[0029] Figure 11 Schematic diagram of a handle of an embodiment;

[0030] Figure 12 Schematic diagram of the steps of a borescope inspection method of an embodiment;

[0031] Figure 13 Partial schematic diagram of the cooperation between the guiding structure and the casing of an embodiment;

[0032] Figure 14 Partial schematic diagram of the inspection of the root of the stator blade of a gas turbine engine of an embodiment;

[0033] Figure 15 Partial schematic view of circumferential blade area inspection of a gas turbine engine according to an embodiment;

[0034] Figure 16 Partial front view of circumferential blade area inspection of a gas turbine engine according to an embodiment;

[0035] Figure 17 Partial schematic view of rotor blade inspection of a gas turbine engine according to an embodiment;

[0036] Figure 18 Partial top view of rotor blade inspection of a gas turbine engine according to an embodiment.

[0037] Reference numerals:

[0038] 1001 - straight pipe section, 10011 - fixed position, 1002 - bent pipe section;

[0039] 1 - first guide pipe, 102 - bent pipe section, 1020 - wavy extension section, 1021 - wave crest, 1022 - wave trough;

[0040] 2 - second guide pipe, 202 - bent pipe section, 2021 - second hook section, 2022 - straight pipe section;

[0041] 3 - third guide pipe, 302 - bent pipe section, 3021 - third hook section, 3022 - straight pipe section;

[0042] 4 - handle, 401 - first blind hole, 402 - second blind hole, 403 - rectangular side, 404 - arc side;

[0043] 5 - casing, 501 - casing hole, 502 - flange surface, 5021 - bolt;

[0044] 6 - inner area of the rotor disk hub of the gas turbine engine, 601 - first exploration point, 602 - next exploration point;

[0045] 7 - circumferential blade area of the gas turbine engine, 701 - first exploration point, 702 - next exploration point;

[0046] 8 - rotor blades of different stages of the gas turbine engine, 801 - first exploration point, 802 - next exploration point. Detailed implementation manners

[0047] Reference will now be made in detail to various embodiments of the present invention, examples of which are shown in the accompanying drawings and described as follows. Although the present invention will be described in conjunction with exemplary embodiments, it should be understood that this specification is not intended to limit the present invention to those exemplary embodiments. On the contrary, the present invention is intended to cover not only these exemplary embodiments, but also various alternative forms, modifications, equivalents and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0048] In the following description, the orientation or positional relationship indicated by terms such as "circumferential", "inner", "outer", "downstream" or other orientation terms is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. At the same time, specific terms are used in this application to describe the embodiments of this application. For example, "one embodiment" or "an embodiment" means a certain feature, structure or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more at different positions in this specification is not necessarily the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of this application can be appropriately combined.

[0049] Reference Figure 1 As shown, in one embodiment, a specific structural example of the guiding structure of the borescope guiding wire may include a guiding tube, and the guiding tube includes a straight tube portion 1001 and a bent tube portion 1002. The bent tube portion 1002 is located downstream of the straight tube portion 1001 and is connected to the straight tube portion 1001. The axis a of the straight tube portion 1001 is arranged non-coincidentally with the extending direction b of the outlet end of the bent tube portion 1002. In some embodiments, the size of the inner diameter D of the guiding tube is 6≤D≤7mm, and the size of the outer diameter d of the guiding tube is 8≤d≤9mm. The guiding tube can guide the guiding wire to the measured point, eliminating the need for the operator to hold it all the time, allowing the operator to perform other tasks, saving physical strength and reducing the occurrence of operation errors, thereby improving the detection efficiency. At the same time, it protects both the detection head and the interior of the engine, preventing damage and saving the detection cost.

[0050] Reference Figure 1 Combined Figure 2 、 Figure 4 、 Figure 7As shown, in one embodiment, a specific structural example of the guiding structure of the borescope guiding wire may be that a plane formed by the extending direction of the straight pipe portion 1001 and the extending direction of the bent pipe portion 1002 is defined as the first plane α. Specifically, the first plane α is formed by the intersection of the axis a of the straight pipe portion 1001 and the extending direction b of the outlet end of the bent pipe portion 1002. The straight pipe portion 1001 has a fixed position 10011 so that the straight pipe portion 1001 is fixed to the casing at the fixed position 10011. The guiding structure includes the first guiding pipe 1 and / or the second guiding pipe 2 and / or the third guiding pipe 3.

[0051] Reference Figure 2 Combined with Figure 3 As shown, specifically, an example of the specific structure of the first guiding pipe 1 may be that the bending direction of the first guiding pipe 1 is located in a plane β perpendicular to the first plane α. The bent pipe portion 102 of the first guiding pipe 1 has a wavy extension section 1020. The bending radius R2 of the wave crest 1021 of the wavy extension section 1020 is 2-5 times the outer diameter d of the first guiding pipe 1. The bending radius R3 of the wave trough 1022 of the wavy extension section 1020 is 2-5 times the outer diameter d of the first guiding pipe 1. The bending angle f1 of the wave crest and the wave trough is 45°-180°.

[0052] Reference Figure 4 Combined with Figure 6 As shown, specifically, an example of the specific structure of the second guiding pipe 2 may be that the bending direction of the second guiding pipe 2 is located in the first plane α. The bent pipe portion 202 of the second guiding pipe 2 has a second hook section 2021. The included angle f2 between the end and the starting end of the second hook section 2021 is 30°-80°. The bending radius R4 of the second hook section 2021 is 2-5 times the outer diameter d of the second guiding pipe 2;

[0053] Reference Figure 7 Combined with Figure 9 As shown, specifically, an example of the specific structure of the third guiding pipe 3 may be that the bending direction of the third guiding pipe 3 is located in the first plane α. The bent pipe portion 302 of the third guiding pipe 3 has a third hook section 3021. The included angle f3 between the end and the starting end of the third hook section 3021 is 100°-170°. The bending radius of the third hook section 3021 is 2-5 times the outer diameter d of the third guiding pipe 3.

[0054] By setting three guiding pipes with different structures, it can meet the guiding of the guiding wire for borescope inspection of different areas of the engine. When it is necessary to detect the blade bodies of multiple-stage low-pressure turbine blades, the first guiding pipe 1 can be selected for cooperative positioning. When it is necessary to detect the roots of the turbine stator blades, the second guiding pipe 2 can be selected for cooperative positioning. When it is necessary to observe the blade area in the circumferential direction of the engine, the third guiding pipe 3 can be selected for cooperative positioning.

[0055] Reference Figure 6 、Figure 9 As shown, in one embodiment, an example of the specific structure of the second guiding tube 2 may further be that the bent tube portion 202 of the second guiding tube 2 includes a straight tube section 2022, and the included angle g between the straight tube section 2022 and the straight tube portion 201 of the second guiding tube 2 is 45° - 180°; an example of the specific structure of the third guiding tube 3 may further be that the bent tube portion 302 of the third guiding tube 3 includes a straight tube section 3022, and the included angle e between the straight tube section 3022 and the straight tube portion 301 of the third guiding tube 3 is 45° - 180°. The included angle between the bent tube portion and the straight tube portion can enable the guiding tube to better avoid the internal components of the engine, prevent collision damage, prevent the introduction of redundant impurities, and reduce additional maintenance costs.

[0056] Reference Figure 10 As shown, in one embodiment, an example of the specific structure of the guiding tube may be that the fixed position 10011 further includes a handle 4, the handle 4 is fixedly connected to the straight tube portion 1001, and the handle 4 and the straight tube portion 1001 define a positioning plane γ. Specifically, the axis a of the straight tube portion intersects with the center line x of the handle 4 to form the positioning plane γ. As Figure 10 Combined with Figure 2 shown, the first plane α of the first guiding tube 1 coincides with the positioning plane γ. As Figure 10 Combined with Figure 5 shown, the included angle c between the first plane α of the second guiding tube 2 and the positioning plane γ is 0 - 90°. As Figure 10 Combined with Figure 8 shown, the included angle h between the first plane α of the third guiding tube 3 and the positioning plane γ is 0 - 90°. Setting the angles between the first plane α of the three guiding tubes and the positioning plane γ to be different can better meet the requirements for guiding the three guiding tubes to different positions for borescope inspection. Without excessive manual operation and judgment by the operator, the guiding tube can be placed at the inspection position without collision.

[0057] Reference Figure 11 As shown, in one embodiment, an example of the specific structure of the handle 4 may be that there are a first blind hole 401 and a second blind hole 402 on both sides respectively. The two sides have an asymmetric structure, one side is a rectangular edge 403, and the other side is an arc edge 404. The diameter of the arc edge 404 is R1. The width W of the handle 4 is greater than the diameter of the casing hole to prevent it from falling into the engine. The handle is provided with blind holes and an asymmetric structure, which helps to refer to and identify the direction of the guiding tube to identify the position of the outlet. In addition, for different types of ducts, such as the above-mentioned first guiding tube 1, second guiding tube 2, and third guiding tube 3, markings can be made on the handle to prevent misidentification. Without manual judgment by the operator, the inspection point can be quickly and accurately positioned without abrasion or collision.

[0058] In another embodiment, the material of the guiding tube is a thermoplastic material with good thermoplasticity. After heating at 70°C - 120°C, the three-dimensional structure of the guiding tube can be adjusted and formed. On the premise of effectively protecting the "detection line / guiding line" and preventing it from rubbing against the internal components of the engine, the three-dimensional structure of the guiding tube can be adjusted by preheating according to the actual situation, so that the guiding tube can match more inspection positions and has a higher utilization rate.

[0059] Reference Figure 12 As shown, in one embodiment, a specific step example of the method for borescope inspection using the guiding structure described above may include the following:

[0060] Step A. For the inspection position at the root of the stator blade or the inner side area of the rotor hub of the gas turbine engine, select the second guiding tube of the guiding structure; for the inspection position at the rotor blade of the gas turbine engine or the end face area of the rotor that needs to view across stages through a relatively far borescope hole, select the first guiding tube of the guiding structure; for the inspection position at the circumferential blade area of the gas turbine engine, select the third guiding tube of the guiding structure.

[0061] Step B. Insert the guiding tube into the inspection hole of the casing until it is fixed to the casing, and there is no collision between the guiding tube and the components inside the casing.

[0062] Step C. Insert the guiding wire and the detection head of the borescope into the guiding tube until the detection head reaches the inspection position.

[0063] In an alternative embodiment, the specific step example of Step B may further include that if there is a collision between the guiding tube and the internal components of the casing, the guiding tube made of thermoplastic material can be heated to adjust the structure of the bent tube part of the guiding tube until there is no collision between the guiding tube and the internal components of the casing, preventing the introduction of foreign objects.

[0064] In another alternative embodiment, the specific step example of Step B may further include inserting the guiding tube into the inspection hole of the casing, identifying the direction of the guiding tube through the blind holes, rectangular edges, and arc edges of the handle, and adjusting the handle to align the guiding structure correctly with the inspection position.

[0065] Reference Figure 13 As shown, in another embodiment, a casing hole 501 is opened on the casing 5, and a flange surface 502 is provided on the casing hole 501. The flange surface 502 is square and is fixedly connected to the casing 5 by bolts 5021 at the four corners. The handle 4 cooperates with the flange surface 502, and the direction of the guiding tube can be more accurately identified through the positions of the blind holes 401, 402, rectangular edge 403, and arc edge 404 of the handle 4 relative to the flange surface 502, for reference to determine the inspection position. When borescope inspection is not required, the flange surface 502 is in a blocked state.

[0066] Specifically, as Figure 14 shown in the example, the second guiding tube 2 is selected to inspect the inner region 6 of the rotor disk hub of a gas turbine engine. First, the second guiding tube 2 is inserted into the interior of the casing 5 through one or more casing holes 501 of the casing 5. The handle 4 is adjusted to make the positioning plane γ perpendicular to the engine axis i. The second guiding tube 2 is aligned, and after the first inspection point 601 is positioned, the second guiding tube 2 is fixed. Then, the guiding wire and the detection head of the borescope are inserted into the second guiding tube 2 until the detection head reaches the inspection position. After the inspection of the first inspection point 601 is completed, the guiding wire is pulled back so that the detection head is inside the second guiding tube 2. By adjusting the positions of the rectangular edge, arc edge, and blind holes on the handle 4 relative to the flange surface, the next inspection point 602 is positioned. After aligning and fixing the second guiding tube 2, the detection head is extended out of the second guiding tube 2 to reach the inspection position. The above steps are repeated until all inspection points are inspected. After pulling back the guiding wire and placing the detection head outside the second guiding tube 2, the second guiding tube 2 is removed from the casing 5. There is no bumping throughout the process to prevent introducing excessive impurities into the engine interior.

[0067] As Figure 15 combined with Figure 6 shown in the example, the third guiding tube 3 is selected to inspect the circumferential blade region 7 of a gas turbine engine, and the fine structural features thereon can be inspected. First, the third guiding tube 3 is inserted into the interior of the casing 5 through one or more casing holes of the casing 5. The handle 4 is adjusted to make the positioning plane γ perpendicular to the engine axis i. The third guiding tube 3 is aligned, and after the first inspection point 701 is positioned, the third guiding tube 3 is fixed. Then, the guiding wire and the detection head of the borescope are inserted into the third guiding tube 3 until the detection head reaches the inspection position. After the inspection of the first inspection point 701 is completed, the guiding wire is pulled back so that the detection head is inside the third guiding tube 3. By adjusting the positions of the rectangular edge 403, arc edge 404, blind holes 401, 402 on the handle 4 relative to the flange surface 502, the next inspection point 702 is positioned. After aligning and fixing the third guiding tube 3, the detection head is extended out of the third guiding tube 3 to reach the inspection position. The above steps are repeated until all inspection points are inspected. After pulling back the guiding wire and placing the detection head outside the third guiding tube 3, the third guiding tube 3 is removed from the casing 5. There is no bumping throughout the process to prevent introducing excessive impurities into the engine interior.

[0068] As Figure 17With reference to the example shown in 18, the first guiding tube 1 is selected to inspect the rotor blades 8 of different stages of a gas turbine engine. First, the first guiding tube 1 is inserted into the interior of the casing 5 through one or more casing holes of the casing 5. The handle 4 is adjusted to make the positioning plane γ parallel to the engine axis i. The first guiding tube 1 is aligned, and after the first inspection point, the first-stage rotor blade 801, is positioned, the first guiding tube 1 is fixed. Then, the guiding wire and the detection head of the borescope are inserted into the first guiding tube 1 until the detection head reaches the inspection position. After the inspection of the first inspection point 801 is completed, the guiding wire is pulled back so that the detection head is located inside the first guiding tube 1. The handle 4 adjusts the positions of its rectangular edge 403, arc edge 404, blind holes 401, 402 relative to the flange surface 502. After positioning the next inspection point, aligning and fixing the first guiding tube 1, the detection head is extended out of the first guiding tube 1 to reach the inspection position. The above steps are repeated until all inspection points are inspected. After pulling back the guiding wire to place the detection head outside the first guiding tube 1, the first guiding tube 1 is removed from the casing 5. There is no bumping throughout the process to prevent introducing extra impurities into the engine. For inspecting the rotor blades of the Nth stage, the extension length of the bent tube portion of the first guiding tube 1 selected is the first length, and for inspecting the rotor blades of the (N + 1)th stage, the extension length of the bent tube portion of the first guiding tube 1 selected is the second length, and the second length is greater than the first length.

[0069] In summary, the beneficial effects of the guiding structure of the borescope guiding wire and the borescope inspection method introduced in the above embodiments include but are not limited to one or a combination of the following:

[0070] 1. The guiding tube can guide the guiding wire to the measured point, eliminating the need for the operator to always hold it by hand, allowing the operator to perform other tasks, saving physical strength and reducing the likelihood of operation errors, thus improving the detection efficiency. At the same time, it protects both the detection head and the interior of the engine from being bruised, saving the detection cost.

[0071] 2. Three guiding tubes with different structures are provided to meet the guiding of the guiding wire for borescope inspection of different regions of the engine. When it is necessary to detect the blade bodies of multiple stages of low-pressure turbine blades, the first guiding tube can be selected for positioning; when it is necessary to detect the roots of the turbine stator blades, the second guiding tube can be selected for positioning; when it is necessary to observe the blade regions in the circumferential direction of the engine, the third guiding tube can be selected for positioning.

[0072] 3. The angle between the bent tube portion and the straight tube portion enables the guiding tube to better avoid the internal components of the engine, preventing bruising, preventing the introduction of extra impurities, and reducing additional maintenance costs.

[0073] 4. The blind holes and the asymmetric structure of the handle help to identify the direction of the guiding tube by reference, allowing the operator to quickly and accurately position the inspection point without manual judgment and without abrasion or collision.

[0074] 5. The guiding tube has good thermoplasticity. By preheating, the three-dimensional structure of the guiding tube is adjusted, enabling the guiding tube to match more detection positions and having a higher utilization rate.

[0075] 6. The method of borescope inspection using the guiding structure as described above is efficient and convenient, and can avoid the probe head from colliding with the internal parts of the engine.

[0076] Although the present invention is disclosed above in a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and decoration made to the above embodiment based on the technical essence of the present invention without departing from the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A guiding structure for a borescope guiding wire, characterized in that, Comprising a guide tube, the guide tube comprising: A straight tube portion; and A bent tube portion; The bent tube portion is located downstream of the straight tube portion and connected to the straight tube portion, and the axis of the straight tube portion is arranged non-coincidentally with the extending direction of the outlet end of the bent tube portion; Defining the plane formed by the extending direction of the straight tube portion and the extending direction of the bent tube portion as the first plane, the straight tube portion has a fixed position so that the straight tube portion is fixed to the casing at the fixed position; the guiding structure comprises: A first guide tube, the bending direction of the first guide tube being in a plane perpendicular to the first plane; the bent tube portion of the first guide tube has a wavy extension section, the bending radii of the wave crests and wave troughs of the wavy extension section being 2-5 times the outer diameter of the guide tube, and the bending angles of the wave crests and wave troughs being 45°-170°; and / or A second guide tube, the bending direction of the second guide tube being in the first plane, the bent tube portion of the second guide tube having a second hook section, the included angle between the end and the start of the second hook section being 30°-80°, and the bending radius of the second hook section being 2-5 times the outer diameter of the guide tube; And / or A third guide tube, the bending direction of the third guide tube being in the first plane, the bent tube portion of the third guide tube having a third hook section, the included angle between the end and the start of the third hook section being 100°-170°, and the bending radius of the third hook section being 2-5 times the outer diameter of the guide tube.

2. The guiding structure according to claim 1, characterized in that, The bent tube portion of the second guide tube includes a straight tube section, and the included angle between the straight tube section and the straight tube portion of the second guide tube is 45°-180°; the bent tube portion of the third guide tube includes a straight tube section, and the included angle between the straight tube section and the straight tube portion of the third guide tube is 45°-180°.

3. The guiding structure according to claim 1, wherein, The fixed position further includes a handle, the handle being fixedly connected to the straight tube portion, and the handle and the straight tube portion defining a positioning plane, the first plane of the first guide tube coinciding with the positioning plane, the included angle between the first plane of the second guide tube and the positioning plane being 0-90°, and the included angle between the first plane of the third guide tube and the positioning plane being 0-90°.

4. The guiding structure according to claim 3, characterized in that, The handle has an asymmetric structure on both sides, with a first blind hole, a second blind hole, a rectangular edge, and an arc edge on both sides respectively.

5. The guiding structure according to claim 1, characterized in that The material of the guide tube is a thermoplastic material.

6. A borescope inspection method, characterized in that, Comprising adopting the guiding structure according to any one of claims 1-5, the borescope inspection method comprising: Step A. For the area where the inspection position is the root of the stator blade or the inner side of the rotor hub of a gas turbine engine, select the second guide tube of the guiding structure; for the inspection position being the rotor blade of a gas turbine engine or the end face area of the rotor that needs to view across stages after passing through a relatively far borescope hole, select the first guide tube of the guiding structure; for the inspection position being the circumferential blade area of a gas turbine engine, select the third guide tube of the guiding structure; Step B. Insert the guide tube into the inspection hole of the casing until it is fixed to the casing, and there is no collision between the guide tube and the components inside the casing; Step C. Insert the guiding wire and the detection head of the borescope into the guide tube until the detection head reaches the inspection position.

7. The borescope inspection method according to claim 6, wherein In step A, for inspecting turbine rotor blades of a gas turbine engine with different stages in the inspection position, the first guide tube of the guide structure is selected, and for inspecting rotor blades of the Nth stage, the extended length of the bent tube portion of the first guide tube is selected to be a first length, and for inspecting rotor blades of the N+1th stage, the extended length of the bent tube portion of the first guide tube is selected to be a second length, and the second length is greater than the first length.

8. The borescope inspection method according to claim 6, characterized in that, The guide tube is made of thermoplastic material. In step B, if the guide tube collides with components inside the casing, the guide tube is heated and the structure of the bent tube portion is adjusted until there is no collision between the guide tube and components inside the casing.

9. The borescope inspection method according to claim 6, wherein, The guide structure also includes a handle, and the handle and the straight tube portion define a positioning plane. The first plane of the first guide tube coincides with the positioning plane, the angle between the first plane of the second guide tube and the positioning plane is 0°-90°, and the angle between the first plane of the third guide tube and the positioning plane is 0°-90°. In step B, the guide tube is extended from the exploration hole of the casing, and the guide structure is straightened by adjusting the position of the handle.

Images