Method for x-ray inspection of power turbine rotor combined blade roots

Abstract

The application discloses a power turbine rotor combination blade root X-ray detection method. The power turbine rotor combination comprises a long rod and a wheel disc located on two sides of a blade respectively, and the wheel disc has a bottom recess at the center. The X-ray directional penetration is implemented on all blade roots of the power turbine rotor combination in the circumferential direction, and a film is tightly attached to the circular arc surface of the annular structure during the X-ray directional penetration. The detection method creatively regards the blade root as an annular structure, reduces the penetration thickness, can significantly reduce energy loss and improve detection sensitivity, realizes complete image of the detected part, improves the contrast of the film, and guarantees stable and reliable detection quality of the blade root. The directional penetration device is used for auxiliary detection, can quickly clamp and stabilize the power turbine rotor combination, guarantees that the ray beam is perpendicular to the blade root, and tightly attaches the film and the effective penetration area, and improves the image contrast and the detection sensitivity.

Description

Technical Field

[0001] This invention relates to the field of precision hole wear repair technology for aero-engine components, specifically to an X-ray inspection method for the root of a power turbine rotor assembly blade. Background Technology

[0002] In the machinery manufacturing industry, X-ray inspection technology is one of the main methods for assessing the internal quality of inspected parts. Castings are generally inspected using X-ray directional radiography technology.

[0003] Instruction manual attached Figure 4 A power turbine rotor assembly is shown, with the blade root as indicated by the arrow in the figure. Defect detection at the blade root is generally carried out using a vertical disc directional X-ray method. The blade root is the X-ray inspection area. Due to the structural reasons of the parts and the requirements to ensure sensitivity, only the single-wall single-image X-ray method with the source on the outside can be used.

[0004] by Figure 4 Taking the case size as an example, because the depth of the area to be inspected is only 5.9 mm and has a curved shape with a diameter of 80 mm, and the intensifying film wrapped in it has a certain thickness, placing it in this groove requires the use of traditional temporary fixing tools such as wooden T-shaped blocks, corner blocks, cardboard, sponges, rubber foam, and clips for radiography. Often, the film will detach from the groove at the root of the blade, and most of the film that does not detach cannot guarantee that it is tightly attached to the inspected area. This results in incomplete images of the inspected area, significant geometric unclearness, and severe image distortion on the film, leading to numerous rework attempts, time-consuming placement, and a limited number of parts that can be placed within the effective exposure range. Furthermore, although the sensitivity of the film obtained in this way meets the standard requirements, the large thickness of the radiograph makes it difficult to detect small images, easily leading to missed detections.

[0005] Statistics show that all the defects such as cracks and porosity found during over-revving, commissioning, and troubleshooting of the power turbine rotor assembly, as discovered through fluorescent inspection, occurred in [location missing]. Figure 4 The location indicated by the arrow at the root of the middle leaf.

[0006] Patent CN108593762A discloses a defect detection process for gas turbine blades, relating to the field of gas turbine blade inspection technology. The process includes: Step 1, preparing an auxiliary sample with multiple simulated defects; Step 2, using an array eddy current detector to inspect the auxiliary sample and recording the detection signals obtained during the inspection; Step 3, using the array eddy current detector to inspect the gas turbine blade, recording the detection signals obtained during the observation and inspection, comparing the detection signals of the gas turbine blade with those of the auxiliary sample, and analyzing the location and size of defects on the gas turbine blade. While this gas turbine blade defect detection process can achieve non-destructive testing of gas turbine blades, it primarily targets blade defects. It can clearly identify the location of blade defects, quantify the size of defects, and qualitatively characterize defects, but it still cannot overcome the problem of missed defects at the blade root. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide an X-ray inspection method for the root of the combined blade of a power turbine rotor that can achieve complete images of the inspected area and avoid missed defects.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] An X-ray inspection method for the root of a power turbine rotor assembly blade is disclosed. The power turbine rotor assembly includes a long rod and a disk located on both sides of the blade. The disk has a concave bottom at its center. The inspection method mainly targets the connection between the blade root and the disk for X-ray inspection. Specifically, the root of all blades in the circumferential direction of the power turbine rotor assembly is regarded as a ring structure and X-ray directional radiography is performed. During X-ray directional radiography, a film is tightly attached to the arc surface of the ring structure.

[0010] Furthermore, the X-ray machine used for the X-ray directional radiography employs an exposure dose of 20 mA × 1.5 min.

[0011] Furthermore, the X-ray machine uses a focal length of 1400mm, and the radiography is divided into multiple segments, with a tube voltage of 110KV.

[0012] Furthermore, during radiography, there is an overlap between adjacent films. The principle for selecting the width of the film is: excluding the overlap, the product of the remaining width of each film segment and the number of radiography segments matches the length of the arc surface of the annular structure.

[0013] Furthermore, the surface of the film away from the leaf root is provided with lead plate anti-scattering lines.

[0014] Furthermore, the lead plate is 1 mm thick.

[0015] Furthermore, the beam deflection angle during X-ray directional irradiation is no greater than 5°.

[0016] Furthermore, the power turbine rotor assembly is clamped using a directional imaging device, which includes a base, a first support and a second support spaced apart on the base. The first support and the second support are used to support the power turbine rotor assembly in parallel. The first support is used to place the long rod of the power turbine rotor assembly. The end of the second support away from the base has an arc structure. The arc of the arc structure is adapted to the machining inner diameter of the disc. The film is close to the root of the blade of the power turbine rotor assembly along the arc structure of the second support.

[0017] Furthermore, a pressure plate is provided above the arc structure of the second support to stabilize the position of the film.

[0018] Furthermore, the second support has a protrusion on the end face facing the first support, the protrusion being used to press against the bottom recess at the center of the wheel.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] This detection method creatively treats the leaf root as a ring structure, reducing the thickness of the film, which can significantly reduce energy loss and improve detection sensitivity, achieve complete images of the inspected area, improve film contrast, and ensure stable and reliable leaf detection quality.

[0021] The use of a directional transillumination device for auxiliary detection enables rapid clamping and stabilization of the power turbine rotor assembly, ensuring that the X-ray beam is perpendicular to the blade root and that the film and the effective transillumination area are in close contact, thereby improving image contrast and detection sensitivity.

[0022] Using this detection method can improve detection efficiency by more than 50%. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the root of the combined blades of the power turbine rotor as described in Embodiment 1 of the present invention;

[0024] Figure 2 This is a schematic diagram of the directional radiography device described in Embodiment 3 of the present invention;

[0025] Figure 3 For mounting the power turbine rotor assembly in Figure 2 A schematic diagram of the directional radiography device shown;

[0026] Figure 4 This is a schematic diagram of the power turbine rotor assembly described in the background art;

[0027] Figure 5This is a schematic diagram of the defective part of the power turbine rotor assembly described in the background art. Detailed Implementation

[0028] To clearly illustrate the technical features of this solution, the following detailed description, in conjunction with the accompanying drawings, will explain the technical solution in detail.

[0029] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0030] Furthermore, it should be understood in the description of this application that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0032] In this application, unless otherwise expressly specified and limited, the "above" or "below" of the second feature 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. In the description of this specification, references to terms such as "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples.

[0033] Example 1

[0034] A method for X-ray inspection of the root of combined blades in a power turbine rotor is provided, such as... Figure 4 As shown, the power turbine rotor assembly includes a long rod 12 and a disk 13 located on both sides of the blade 11. The disk has a concave bottom at its center. The parts to be inspected are as follows: Figure 5 As indicated by the arrow in the "Radiation Inspection Area" section, this mainly refers to the connection between the blade root and the rotor disk. This inspection method treats the circumferential blade roots of the power turbine rotor assembly as a ring structure and performs directional X-ray radiography (using an external source, single-wall, single-image method). Figure 1 As shown, during X-ray directional radiography, film 2 is placed tightly against the arc surface of the annular structure (i.e., the area to be inspected by X-rays). This directional radiography method ensures the reliability of X-ray inspection quality at the blade root, thereby guaranteeing the stability and reliable lifespan of the engine.

[0035] Specifically, radiography is divided into multiple segments, meaning the film is also divided into multiple segments for radiography; in this embodiment, it is divided into six segments. During radiography, adjacent film segments overlap (industry standards stipulate that each side of the film must have an overlap of at least 10mm). The specific principle for selecting the film width is: excluding the overlap, the product of the remaining width of each film segment and the number of radiography segments matches the length of the arc surface of the annular structure. For example... Figure 5 If the diameter of the arc at the base of the middle leaf blade is 80mm, then the film size can be cut to [size missing]. In this embodiment, a 62mm × 150mm film is used (where the 62mm width is flush with the Φ80 arc, and the 150mm length is used to place the marking 3, which marks the segment blade number, part sequence number, and exposure date on the power turbine rotor assembly blades), to facilitate close contact between the film and the effective exposure area; in addition, a lead plate 4 is provided on the surface of the film away from the blade root to prevent scattering rays, thereby improving the contrast of the film (the film becomes a negative after exposure and darkroom processing) and the completeness of the image on the film, thus improving image contrast and detection sensitivity; the thickness of the lead plate is preferably 1mm.

[0036] Furthermore, X-ray directional radiography uses an X-ray machine with a high tube current, employing a larger exposure dose and a lower tube voltage. A larger exposure dose (higher tube current) is beneficial for improving detection efficiency, image contrast, and detection sensitivity. Specifically, the X-ray machine used has an exposure dose of 20mA × 1.5min and a tube voltage of 110KV. The beam deflection angle during X-ray directional radiography should not exceed 5°.

[0037] When performing X-ray directional radiography, other items such as image quality meter 5 and marking 3 should be performed in accordance with standard requirements, which is conducive to quality assessment and archiving for future reference.

[0038] The detection method in this embodiment can ensure the angle of the central ray beam during the detection process, reduce the thickness of the light transmission, reduce energy loss, control the detection rate of porosity and cracks in precision castings, improve image contrast and detection sensitivity, and ensure the stable and reliable quality of the engine while reducing unnecessary machining work.

[0039] Example 2

[0040] A method for X-ray inspection of the root of combined blades in a power turbine rotor is provided, such as... Figure 4 As shown, the power turbine rotor assembly includes long rods and a disk located on both sides of the blades. The disk has a concave bottom at its center. The parts to be inspected are as follows: Figure 5 The arrow indicates the "X-ray Inspection Location". This inspection method treats the roots of all blades in the circumferential direction of the power turbine rotor assembly as a ring structure and performs directional X-ray radiography. During directional X-ray radiography, film is placed tightly against the arc surface of the ring structure. This directional radiography method ensures the reliability of the X-ray inspection quality at the blade roots, thereby guaranteeing the stability and reliable lifespan of the engine.

[0041] The difference between this embodiment and Embodiment 1 is that the film size can also be slightly smaller than the length of the arc surface, for example... Figure 5 If the diameter of the arc at the root of the blade is 80mm, the film size can be cut to 64mm×150mm (where the width of 64mm fits tightly against the Φ80 arc, and the length of 150mm is used for marking, which is to mark the segment blade number, part number and exposure date on the power turbine rotor assembly blade), so that the film and the effective exposure area can fit tightly. In fact, the film size can be between 70mm and 80mm. In addition, a lead plate is provided on the surface of the film away from the blade root to prevent scattering, thereby improving the contrast of the film and the completeness of the image on the film, improving image contrast and detection sensitivity. The thickness of the lead plate is preferably 1mm.

[0042] Furthermore, X-ray directional radiography uses an X-ray machine with a high tube current, employing a larger exposure dose and a lower tube voltage. A higher exposure dose improves detection efficiency, image contrast, and detection sensitivity. Specifically, the X-ray machine used has an exposure dose of 20mA × 1.5min and a tube voltage of 110kV. The beam deflection angle during X-ray directional radiography should not exceed 5°.

[0043] When performing X-ray directional radiography, other aspects such as image quality meters and markings should be carried out in accordance with standard requirements, which is conducive to quality assessment and archiving for future reference.

[0044] Example 3

[0045] This embodiment provides a directional radiographic device applied to the one in Embodiment 1 for clamping and testing the power turbine rotor assembly, such as... Figure 2 and Figure 3 As shown, the directional radiography device includes a base 61, a first support 62 and a second support 63 spaced apart on the base, the first support 62 and the second support 63 arranged in parallel for horizontally supporting the power turbine rotor assembly. The first support 62 is used to hold the long rod 12 of the power turbine rotor assembly, and the portion of the long rod extending beyond the end face of the first support facilitates manual rotation of the parts during segmented radiography. The first support 62 has a "7"-shaped opening 621 through which the long rod 12 is inserted; this "7"-shaped opening facilitates the loading, unloading, and stabilization of the parts. The end of the second support 63 furthest from the base has an arc-shaped structure 631. The arc of the arc structure is adapted to the inner diameter of the rotary disc. The wrapped film 2 is close to the root of the power turbine rotor assembly blades along the arc structure, which helps to ensure that the inspected area (root of the turbine rotor assembly blades) is in close contact with the film, ensuring the completeness of the image in the inspected area and improving the detection contrast and sensitivity. The second support 63 has a protrusion 632 on the end face facing the first support. The protrusion 632 is used to press against the bottom recess of the center of the rotary disc and control the rotor assembly to prevent it from moving up, down, left, or right. A pressure plate 64 is also provided above the arc structure of the second support 63. The pressure plate 64 helps to ensure the stability of the film position and ensure the completeness of the image in the inspected area.

[0046] The aforementioned directional radiography device can quickly clamp and stabilize the casting under inspection, ensure the X-ray beam is perpendicular to the blade root, and fix the relative position of the inspection area and the film. It offers good stability, ensuring the angle of the central X-ray beam during inspection, controlling the detection rate of porosity and cracks in precision castings, and improving image contrast and detection sensitivity. The angle rotation of the inspected casting during segmented radiography is quick and convenient. Using this directional radiography device for radiography setup results in high inspection efficiency and allows for systematic control of the inspection process quality.

[0047] Example 4

[0048] This embodiment describes the specific detection process step by step:

[0049] S1. Mark the segment blade numbers on the combined blades of the power turbine rotor, and write the part sequence number on the long rod;

[0050] S2. After the marked power turbine rotor assembly is clamped onto the directional radiography device of Example 3, it is placed firmly in the radiographic field (controlling the ray beam offset angle to be no more than 5°). The cut film (with a lead plate placed on the back) is tightly attached to the Φ80 arc, and the pressure plate is used to press the film firmly.

[0051] S3. Display the image quality monitor, label, date, etc., as required;

[0052] S4. Close the machine room door and perform X-ray fluoroscopy according to the parameters on the inspection card;

[0053] S5. After the exposed film is processed in a darkroom, the quality of the root of the turbine rotor assembly blades can be evaluated.

[0054] It should be noted that some dimensions in the accompanying drawings are for illustrative purposes only and do not constitute a limitation on this technical solution.

[0055] Obviously, the above embodiments are merely examples to clearly illustrate the technical solutions of the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for X-ray inspection of the root of a turbine rotor assembly blade, the turbine rotor assembly comprising a long rod and a disk located on both sides of the blade, the disk having a concave bottom at its center, characterized in that, The root of all blades in the circumferential direction of the power turbine rotor assembly is regarded as a ring structure and X-ray directional radiography is performed. During X-ray directional radiography, film is used to be closely attached to the arc surface of the ring structure. The power turbine rotor assembly is clamped using a directional imaging device, which includes a base, a first support and a second support spaced apart on the base. The first and second supports are used to support the power turbine rotor assembly in parallel. The first support is used to place the long rod of the power turbine rotor assembly. The first support has a "7"-shaped opening through which the long rod is inserted. The end of the second support away from the base has an arc structure. The arc of the arc structure is adapted to the inner diameter of the rotor. The film is placed close to the root of the blades of the power turbine rotor assembly along the arc structure of the second support. A pressure plate is also provided above the arc structure of the second support to stabilize the position of the film; The second support has a protrusion on the end face facing the first support, the protrusion being used to press against the bottom recess at the center of the wheel.

2. The X-ray detection method for the root of the combined blades of a power turbine rotor according to claim 1, characterized in that, The X-ray machine used for the X-ray directional radiography employed an exposure dose of 20 mA × 1.5 min.

3. The X-ray detection method for the root of the combined blades of a power turbine rotor according to claim 2, characterized in that, The X-ray machine uses a focal length of 1400mm, and the radiography is divided into multiple segments, with a tube voltage of 110KV.

4. The X-ray detection method for the root of the combined blades of a power turbine rotor according to claim 3, characterized in that, During radiography, there is an overlap between adjacent films. The principle for selecting the width of the film is: excluding the overlap, the product of the remaining width of each film segment and the number of radiograph segments should match the length of the arc surface of the annular structure.

5. The X-ray detection method for the root of the combined blades of a power turbine rotor according to claim 1, characterized in that, The surface of the film away from the leaf root is provided with lead plate anti-scattering lines.

6. The X-ray detection method for the root of the combined blades of a power turbine rotor according to claim 5, characterized in that, The lead plate is 1 mm thick.

7. The X-ray detection method for the root of the combined blades of a power turbine rotor according to claim 1, characterized in that, The beam offset angle during X-ray directional radiography should not exceed 5º.

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