A wrinkle standard part and a measuring method applied to the measurement of the bending deformation quality of a catheter

Abstract

This invention discloses a wrinkle standard and measurement method for measuring the quality of catheter bending deformation. The standard includes a cylindrical body with several annular grooves along its circumference on its outer surface. Each annular groove has a different depth and is coaxial with the cylindrical body. Each annular groove is used to measure wrinkle degree, and the cylinder with annular grooves of unequal depth is a standard with unequal wrinkle degree. A coordinate measuring machine (CMM) is used to calibrate the standard: First, coordinate points are collected on the end face of the standard and fitted to obtain a reference plane; then, coordinate points are collected on the side face and the surface of the annular groove, and projected onto the reference plane along the central axis to obtain the nominal diameter of the standard body and the diameter of the annular groove; finally, the wrinkle degree corresponding to each annular groove is calculated, completing the fabrication of the wrinkle standard. This invention establishes a wrinkle degree detection and evaluation standard for catheter bending deformation, solving the problem that coordinate measuring equipment cannot measure catheter wrinkle degree. It has good versatility and strong practicality.

Description

Technical Field

[0001] This invention relates to the field of aerospace manufacturing and discloses a wrinkle standard and measurement method for measuring the quality of duct bending deformation. Background Technology

[0002] In the aerospace manufacturing industry, due to limitations in application scenarios and assembly space, conduit components are bent into various lengths, angles, and spatial shapes. During the bending deformation process, due to the poor tangential stability of the pipe wall, wrinkles of varying degrees easily appear on the conduit surface when the tangential stress is too high and external disturbances are present. These wrinkles not only affect the transmission speed of the internal fluid medium but also lead to a reduction in the thickness and strength of the outer wall of the bent section, and may even cause the pipe body to crack, seriously affecting the manufacturing quality of the product. Therefore, the degree of wrinkling has become an important indicator for evaluating the quality of conduit bending deformation.

[0003] Methods for measuring catheter wrinkle degree are mainly divided into contact-based fixture measurement and non-contact optical measurement. Fixture measurement typically uses vernier calipers and special templates, relying on manual judgment. Optical measurement calculates the wrinkle degree by collecting and analyzing the three-dimensional surface data of the wrinkled area. Because the two methods operate on different principles, their measurement performance varies when applied to different types of catheter wrinkles. Therefore, to evaluate the measurement capabilities of different equipment or methods for catheter bending deformation quality, it is necessary to design a standard component for wrinkle degree measurement, enabling parameter traceability and improving the catheter manufacturing quality evaluation system. Furthermore, since catheter wrinkles are usually small in size and indistinct, commonly used coordinate measuring machines (CMMs) cannot measure the wrinkle degree of catheters; therefore, designing a standard component preparation method for catheter wrinkle degree is particularly important. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the technical problem to be solved by this invention is to provide a wrinkle standard for measuring the quality of catheter bending deformation, which is calibrated using a coordinate measuring machine to evaluate the catheter bending deformation quality measurement performance of the testing equipment.

[0005] The technical solution adopted by the present invention to achieve the above objectives is as follows:

[0006] A wrinkle standard for measuring the bending deformation quality of a conduit includes a cylindrical body. Several annular grooves are formed along the circumference of the outer surface of the cylindrical body. The depth of each annular groove is different, and the annular groove is coaxial with the cylindrical body. Each annular groove is used to measure the wrinkle degree. The cylinder with annular grooves of unequal depth is a standard for unequal wrinkle degree.

[0007] The cylinder is made of metal.

[0008] The cylinder is made of aluminum alloy, and the surface roughness is less than 3.2 mm.

[0009] One end face of the cylinder is perpendicular to the central axis of the cylinder and serves as the fitting reference plane of the standard part, denoted as end face 1.

[0010] The axial width w of each annular groove on the surface of the cylinder is equal, and w ∈ {0 < w < 20 mm}, and the depths h of each annular groove are not equal, and h ∈ {0 < h < 10 mm}.

[0011] The surface of the standard part is deburred and anodized.

[0012] The multi-segment unequal waviness standard part is used to measure the accuracy of the waviness measurement value of the measured object. If the measurement value exceeds the standard value error range, it is determined that the measured waviness is inaccurate.

[0013] A waviness standard part measurement method applied to the measurement of the bending deformation quality of a catheter. The waviness of each unequal waviness standard part is measured by collecting the coordinate points of the data points on the surface of the standard part by a coordinate measuring machine, and the standard value of the parameters of the standard part is calculated, including the following steps:

[0014] (1) Using a metrological coordinate measuring machine, after completing the probe calibration, place the standard part within the measurement range to ensure that all points on the surface of the standard part can be measured.

[0015] (2) On end face 1 of the standard part, collect l equally spaced position points around the axis, denoted as p tk , s ,

[0018] ,

[0017] , sj , , (i = 1,..., l), and use the least squares plane fitting method to calculate the normal vector ν of end face 1 and a point p x .

[0016] (3) Take an annular area s on the side surface of the standard part where there is no annular groove, and collect m equally spaced position points around the axis on its surface, denoted as p sj (s = 1,..., z)(j = 1,..., m); on the surface of the annular groove t, collect n equally spaced position points around the axis, denoted as p tk (k = 1,..., n); project the position points p sj and p tk , along the normal vector ν onto end face 1, and calculate the projection points p′ sj and p′ tk ;

[0017] (4) Based on the three-dimensional coordinates of the collected position points p′ sj , use the least squares circle fitting method to calculate the diameter of the annular area s, denoted as D s ; The nominal diameter D of the standard part is calculated as:

[0018]

[0019] Based on the acquisition location point p′ tk Using the three-dimensional coordinates of the annular groove t, the diameter of the groove, denoted as d, is calculated using the least squares circle fitting method. t ;

[0020] (5) Each annular groove of the standard part represents a wrinkle, and its wrinkle degree δ t The calculation is as follows:

[0021]

[0022] Here, the wrinkle measurement value of the standard part is the standard value of the wrinkle measurement of that standard part.

[0023] The present invention has the following beneficial effects and advantages:

[0024] 1. The present invention designs a wrinkle standard part for measuring the bending deformation quality of conduits. It adopts a cylindrical structure, which is simple in structure, easy to machine, and has good versatility.

[0025] 2. The method of the present invention designs a wrinkle standard for measuring the bending deformation quality of catheters. It adopts a segmented groove structure, which covers a variety of wrinkle depths and can evaluate the measurement capability of catheter testing equipment for different types of wrinkles.

[0026] 3. The wrinkle degree standard part measurement method described in this invention solves the problem that coordinate measuring equipment cannot measure the wrinkle degree of the catheter, traces the index accuracy of the standard part to the three coordinate measuring equipment, and improves the manufacturing quality evaluation system of the catheter. Attached Figure Description

[0027] Figure 1 This is a front view of a wrinkle standard component used for measuring the bending deformation quality of a conduit, as described in this invention.

[0028] Figure 2 This is a top view of a wrinkle standard component used for measuring the bending deformation quality of a conduit, as described in this invention.

[0029] Figure 3 This is a schematic diagram of data acquisition using a coordinate measuring machine in a method for measuring the wrinkle degree of a standard part used to measure the bending deformation quality of a conduit. Detailed Implementation

[0030] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of the specific implementation methods of the present invention in conjunction with the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the invention. Therefore, the present invention is not limited by the specific implementations disclosed below.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0032] As Figures 1-2 shown, a waviness standard part for measuring the quality of catheter bending deformation includes a cylinder as the main body of the standard part, with a standard cylindrical shape. A number of annular grooves are machined on the surface of the cylinder along the circumference. The depth of each annular groove is different, and the annular groove and the cylinder have the same central axis. Each of the annular grooves is used to measure the waviness, and the cylinder with annular grooves of unequal depths is a standard part of unequal waviness.

[0033] The material of the cylinder is aluminum alloy, with a length of 300 mm, an outer surface diameter of 62 mm, a surface roughness less than 3.2 mm, and chamfers are provided at both ends. The angle of the chamfer is 45°, and the length of the right-angle side is 1 mm. One end face of the cylinder is required to be perpendicular to the central axis of the cylinder, serving as the fitting reference plane in the preparation method of the standard part, denoted as end face 1.

[0034] Four annular grooves are machined on the surface of the cylinder, arranged at equal intervals along the central axis, with an interval of 10 mm. The first annular groove is in the axial direction and is 20 mm away from the perpendicular end face. The axial width w of the annular groove is equal, w ∈ {0 < w < 20 mm}, and the depths h of the annular grooves are all unequal, h ∈ {0 < h < 10 mm}. As an example, the specific data is as follows: the axial width of the annular grooves is all 12 mm, and the radial depths are 0.1 mm, 0.2 mm, 1 mm, and 1.5 mm respectively, that is, the outer surface diameters are 61.9 mm, 61.8 mm, 61 mm, and 60.5 mm respectively, the depth tolerance is 0.02 mm, and the surface roughness is less than 1.6 mm.

[0035] The surface of the waviness standard part is deburred and an anodic oxidation treatment is performed.

[0036] As Figure 3 shown, a method for manufacturing a waviness standard part for measuring the quality of catheter bending deformation in the present invention includes the following steps:

[0037] (1) After completing the stylus calibration using a metrology-grade coordinate measuring machine, fix the standard part within the measurement range to ensure that all points on the surface of the standard part can be measured.

[0038] (2) On the end face 1 of the standard part, collect l equally spaced position points around the axial direction, denoted as p. i (i = 1, ..., l), using the least squares plane fitting method, the normal vector ν of end face 1 and a point p on the face are calculated. x .

[0039] (3) On the side of the standard part (non-annular groove), take annular area 1 and annular area 2. On the surface of the two annular areas, collect m position points at equal intervals around the axial direction, denoted as p. sj (s=1,2)(j=1,…,m); n position points are collected at equal intervals around the axial direction on the surfaces of annular grooves 1-4, denoted as p. tk (t=1,2,3,4)(k=1,…,n). Position point p sj and p tk Projecting along the normal vector onto end face 1, the projection point is calculated according to the following formulas (1)-(8) and denoted as p′. sj and p′ tk :

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048] (4) Based on the acquisition location point p′ sj Using the three-dimensional coordinates of the annular region 1 and annular region 2, the diameters are calculated using the least squares circle fitting method (at least two annular regions are measured), and denoted as D. s (s=1,2). Therefore, the nominal diameter D of the standard part is calculated as follows:

[0049]

[0050] Based on the acquisition location point p′ tkUsing the three-dimensional coordinates of the annular groove t, the diameter of the groove, denoted as d, is calculated using the least squares circle fitting method. t (t = 1, 2, 3, 4).

[0051] (5) Each annular groove of a standard part can represent one wrinkle, and its wrinkle degree δ t (t=1,2,3,4) can be calculated as:

[0052]

[0053] Here, the wrinkle measurement value of the standard part is the standard value of the wrinkle measurement of that standard part.

[0054] Example:

[0055] A wrinkle standard part was manufactured according to the method of the present invention, with the relevant calibration parameters l set to 20, m set to 50, and n set to 50. After manufacturing, the standard part had a diameter of 62.0136 mm, and the standard values ​​for the annular groove diameters were 61.9133 mm, 61.8132 mm, 60.9884 mm, and 60.4591 mm, respectively, with wrinkle standards of 0.0809%, 0.1616%, 0.8266%, and 1.2534%, respectively.

[0056] The wrinkle degree standard of this invention is a calibrator for evaluating wrinkle degree measurement equipment or methods. It is used to verify the accuracy of wrinkle degree measurement equipment or methods and does not realistically mimic a bent conduit. When this wrinkle degree standard is used as the measurement object, and the obtained measurement value is within the error range (exceeding this range indicates non-compliance), it can be determined that the conduit testing equipment or method is sufficiently accurate, and the measuring equipment or method can be used to measure the wrinkle degree of bent conduits with actual bending deformation.

[0057] In summary, the present invention provides a standard part for measuring the wrinkle degree of catheter bending deformation and a method for manufacturing it. It has good versatility and traceability and can be used to evaluate the ability of catheter testing equipment to measure wrinkle degree.

Claims

1. A wrinkle index standard for measuring the quality of duct bending deformation, characterized in that, It includes a cylindrical body. Along the circumference of the outer surface of the cylindrical body, several annular grooves are provided. The depth of each annular groove is different, and the annular grooves are coaxial with the cylindrical body. Each annular groove is used to measure the waviness. The cylinder with annular grooves of different depths is a standard part with different waviness.

2. The wrinkle degree standard component for measuring the bending deformation quality of a conduit according to claim 1, characterized in that, The material of the cylinder is metal.

3. A wrinkle degree standard component for measuring the bending deformation quality of a conduit according to claim 2, characterized in that, The material of the cylinder is aluminum alloy, and the surface roughness is less than 3.2 mm.

4. A wrinkle standard component for measuring the bending deformation quality of a conduit according to claim 1, characterized in that, One end face of the cylinder is perpendicular to the central axis of the cylinder, serving as the fitting reference plane of the standard part, denoted as end face 1.

5. A wrinkle standard component for measuring the bending deformation quality of a conduit according to claim 1, characterized in that, The axial width w of each annular groove on the surface of the cylinder is equal, and w ∈ {0 < w < 20 mm}. The depth h of each annular groove is not equal, and h ∈ {0 < h < 10 mm}.

6. A wrinkle standard component for measuring the bending deformation quality of a conduit according to claim 1, characterized in that, The surface of the standard part is deburred and anodized.

7. The ellipticity standard component for measuring the bending deformation quality of conduits according to claim 1, characterized in that, Multiple standard parts with different waviness are used as the measured object to measure the accuracy of its waviness measurement value. If the measurement value exceeds the error range of the standard value, it is determined that the measured waviness is inaccurate.

8. The method for measuring wrinkleness using a standard component for measuring the bending deformation quality of a conduit, as described in claim 1, is characterized in that... For the waviness of each standard part with different waviness, the coordinate measuring machine is used to collect the coordinate data points on the surface of the standard part, and the standard value of the parameters of the standard part is calculated, including the following steps: (1) Using a metrological coordinate measuring machine, after the probe is calibrated, the standard part is fixed within the measurement range to ensure that all points on the surface of the standard part can be measured; (2) On the end face 1 of the standard part, equidistantly collect l position points around the axis, denoted as p i (i = 1, …, l), the normal vector v of the end face 1 and a point p on the face are calculated by using the least square plane fitting method x; (3) Take an annular region s on the side of the standard part, and collect m position points at equal intervals around the axial direction on its surface, denoted as p. sj (s=1,…,z)(j=1,…,m); On the surface of the annular groove t, n position points are collected at equal intervals around the axial direction, denoted as p. tk (k = 1, ..., n); Set the position point p sj and p tk Project the vector along the normal vector ν onto end face 1, and calculate the projection point p′. sj and p′ tk ; (4) Based on the acquisition location point p′ sj Using the three-dimensional coordinates of the annular region s, the diameter of the annular region s is calculated using the least squares circle fitting method, denoted as D. s The nominal diameter D of a standard part is calculated as follows: Based on the acquisition location point p′ tk Using the three-dimensional coordinates of the annular groove t, the diameter of the groove, denoted as d, is calculated using the least squares circle fitting method. t ; (5) Each annular groove of the standard part represents a wrinkle, and its wrinkle degree δ t The calculation is as follows: Here, the waviness measurement value of the standard part is the standard value of this waviness standard part.

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