An inner surface detection device and method for a solid propellant combined charge

Abstract

The present invention discloses a detection device and method for the inner surface of a solid propellant combined charge. A handheld device is provided, and an optical fiber transmission component for signal transmission is connected to the handheld device. A transfer disk is arranged at the end of the optical fiber transmission component, and at least one branch probe is installed on the transfer disk. The device of the present invention can install different numbers of branch probes according to different combined charge structures, reducing the operation times and steps of the endoscope inside the combined charge propellant, improving safety, and reducing the damage probability of the combined charge propellant.

Description

Technical Field

[0001] The present invention belongs to the technical field of solid propellants, and relates to an inner surface detection device and method for a solid propellant combined charge. Background Art

[0002] During the development process and tests of propellants, whether it is the screw extrusion process, the grain casting process or the casting process, micro-cracks, scratches, depressions, or defects such as poor plasticization may occur on the inner surface of the grain. These defects are not easily detected by conventional X-ray inspections, but they seriously affect the combustion performance of the propellant, causing abnormal working curves and even explosions.

[0003] In terms of technical means, the detection of the inner surface performance is completed by an industrial endoscope. At present, it is mainly used for the inspection of industrial pipelines, the inner cavities of equipment, and closed containers at home and abroad. The domestic propellant industry also only uses it for qualitative detection. By detecting the inner surface performance and measuring the quality of the propellant, its combustion performance can be estimated, and at the same time, relevant measurement data can be transmitted to designers and developers to solve quality problems that may affect the inner surface performance during the R & D process.

[0004] However, when an endoscope with a single probe is used to detect the combined charge of a multi-star hole engine, it will take a long operation time and have many operation steps. It is necessary to insert the probe into each star hole tooth for detection in turn. During this operation process, since the operation of the probe completely depends on manual work, it may scratch the inner surface of the propellant, thus affecting the combustion performance of the combined charge propellant. Summary of the Invention

[0005] In order to overcome the deficiencies of the prior art, the present invention aims to use multi-probe endoscopic optical imaging detection technology to detect the inner surface performance of the propellant charge, reduce the operation steps and operation time during the detection process, reduce the probability of damage to the combined charge propellant, discover various defects affecting the inner surface performance of the propellant charge, and conduct qualitative and quantitative analysis of the defects, so as to achieve the purpose of quality control during the development process of the propellant charge; thus, an inner surface detection device and method for a solid propellant combined charge are provided.

[0006] To achieve the above object, the technical solutions adopted by the present invention include:

[0007] An inner surface detection device for a solid propellant combined charge is provided with a handheld machine, a fiber optic transmission member for signal transmission is connected to the handheld machine, a transfer disk is provided at the end of the fiber optic transmission member, and at least one branch probe is installed on the transfer disk.

[0008] Optionally, the transfer disk is a disk member embedded with a plurality of fiber optic adapters.

[0009] Optionally, at least circumferentially, a plurality of fiber optic adapters are uniformly arranged on the transfer disk.

[0010] Optionally, an optical fiber adapter is also provided at the central position of the adapter plate.

[0011] Optionally, the branch probe includes an optical fiber adapter, a branch optical fiber, a camera, and an objective adapter connected in sequence.

[0012] Optionally, the optical fiber adapter is an ST optical fiber interface.

[0013] Optionally, the optical fiber transmission member is composed of a plurality of optical fibers corresponding to the adapter plate; the outer layer of the optical fiber is a tungsten wire braided layer, and the optical fiber body is wrapped inside; one end of the optical fiber transmission member is connected to the handheld device, and the other end is connected to the adapter plate.

[0014] Optionally, the adapter plate is a cylindrical cavity structure made of titanium alloy. A plurality of optical fiber adapters are buried in the adapter plate, and the optical fiber adapters are FC optical fiber interfaces; the adapter plate adopts the FC protocol to transmit the image data captured by the branch probe via the optical fiber transmission member.

[0015] A method for detecting the inner surface of a composite charge of solid propellant, which is implemented by using the inner surface detection device of the composite charge of solid propellant according to any one of the present inventions, includes the following steps:

[0016] Step 1: Install an unequal number of branch probes according to the grain structure of the composite charge propellant.

[0017] Step 2: Take a photo above the star holes of the composite charge propellant to observe the damage condition of the star hole orifices.

[0018] Step 3: Insert the installed branch probe and the adapter plate into the center of the charge star hole and slowly push it inward. Observe the flaw detection situation on the display screen of the handheld device and mark the image.

[0019] Step 4: Take a photo of the bottom of the star holes of the composite charge propellant to observe the damage condition of the star hole bottoms; when a defect is found during conventional detection and close observation is required, change the telephoto lens to a close-focus lens; store the taken pictures in the handheld device and export them.

[0020] Optionally, the obtained images are judged for results as follows:

[0021] (1) Import the taken images into the image analysis software in JPG format. The pictures are black and white pictures with a gray scale distribution.

[0022] (2) The image analysis software automatically identifies the gray values of the pictures and judges the types of propellant defects, including cracks, pits, protrusions, scratches, as well as foreign objects and dirt.

[0023] The crack defect is a long strip defect with a width greater than 1 mm, and the gray level difference between the center line of the defect and 60% of the pixel points at the defect edge is more than 20;

[0024] The pit defect is a quasi-circular defect with a diameter greater than 1 mm, and the gray level of 60% of the pixel points in the defect is more than 30 higher than that at the defect edge;

[0025] The protrusion defect is a quasi-circular defect with a diameter greater than 1 mm, and the gray level of 60% of the pixel points in the defect is less than 30 lower than that at the defect edge;

[0026] The scratch defect is a long strip defect with a width less than 1 mm, and the gray level difference between the center line of the defect and 60% of the pixel points at the defect edge is more than 20;

[0027] The foreign object defect is an irregular defect with an area greater than 2 mm 2 , and the gray level of 60% of the pixel points in the defect is more than 30 higher than that at the defect edge;

[0028] The dirt defect is an irregular defect with an area greater than 2 mm 2 , and the gray level of 60% of the pixel points in the defect is less than 30 lower than that at the defect edge;

[0029] (3) The software exports the recognized results for secondary screening by humans; when a crack defect is detected on the inner surface, this propellant charge is rejected; when pits, protrusions, and scratches are detected on the inner surface, according to the technical document requirements of the specific product, the number of various defects is counted, and the size of the collected defect images is measured for comprehensive result evaluation; when foreign objects or dirt are detected on the inner surface, first determine whether they can be cleaned. If they can be cleaned cleanly, they are not judged as defects. If they cannot be cleaned, according to the technical document requirements of the specific product, result evaluation is carried out.

[0030] The beneficial effects of the present invention are reflected in:

[0031] A multi-probe inner surface detection device and detection method are invented. Before detection, the structure and quantity of the probes are adjusted according to the grain shape of the composite charge propellant, and the detection of all star hole teeth of the composite charge propellant can be completed in one operation, greatly reducing the operation steps and operation time in the detection process, reducing the probability of damaging the composite charge propellant, and improving the quality stability of the composite charge propellant and the safety of the operation process. Description of the Drawings

[0032] Figure 1 is a schematic structural diagram of the inner surface detection device for the solid propellant composite charge of the present invention;

[0033] Figure 2 is Figure 1 a schematic structural diagram of the adapter plate in

[0034] Figure 3 is Figure 1 a schematic diagram of the branch probe structure in

[0035] Figure 4 is the star hole structure diagram of the combined charge propellant described in Embodiments 1 and 2 of the present invention, where Fig. a is for Embodiment 1 and Fig. b is for Embodiment 2;

[0036] Figure 5 is a scratch diagram of the propellant surface generated by the internal surface detection device of the solid propellant combined charge;

[0037] Figure 6 is a crack defect diagram of the internal surface of the solid propellant combined charge;

[0038] Figure 7 is a pit defect diagram of the internal surface of the solid propellant combined charge;

[0039] Figure 8 is a protrusion defect diagram of the internal surface of the solid propellant combined charge;

[0040] Figure 9 is a foreign object defect diagram of the internal surface of the solid propellant combined charge;

[0041] Figure 10 is a dirt defect diagram of the internal surface of the solid propellant combined charge;

[0042] The meanings of the various labels in the figure are: 1 - handheld device, 2 - optical fiber transmission component, 3 - adapter plate, 31 - optical fiber adapter, 4 - branch probe, 41 - optical fiber adapter, 42 - branch optical fiber, 43 - camera, 44 - objective adapter. Specific embodiments

[0043] The present invention will be further described in detail below in conjunction with specific embodiments.

[0044] In combination with Figure 1-3The solid propellant combined charge inner surface detection device of the present invention is provided with a handheld device 1, and an optical fiber transmission component 2 for signal transmission is connected to the handheld device 1, and an adapter plate 3 is provided at the end of the optical fiber transmission component 2, and at least one branch probe 4 is installed on the adapter plate 3. The handheld device 1 is provided with components such as an LCD display screen, function keys and LED lighting lamps. Correspondingly, the display screen on the handheld device 1 can be divided by numbers according to the number of branch probes 4, and the image captured by each individual branch probe 4 can be displayed separately to achieve accurate observation; the LED lighting lamp is integrated inside the handheld device 1, and the optical fiber transmission component 2 transmits the light source to the branch probe 4; the adapter plate 3 and the branch probe 4 are connected by an optical fiber interface, and multiple optical fibers corresponding to the branch probe 4 are provided in the optical fiber transmission component 2, and images are captured for each branch probe 4 respectively; before the detection, the structure and number of the probes are adjusted according to the medicine type of the combined charge propellant, and the detection of all the star hole teeth of the combined charge propellant can be completed in one operation, which greatly reduces the operation steps and operation time in the detection process, reduces the probability of damage to the combined charge propellant, and improves the quality stability of the combined charge propellant and the safety of the operation process.

[0045] In the embodiment of the present disclosure, the adapter plate 3 is a disk component in which multiple optical fiber transfer ports 31 are buried. One end of the adapter plate 3 is a disk surface, on which the optical fiber transfer ports 31 can be set as needed to meet the detection requirements of multiple channels. At the same time, the other end of the adapter plate 3 is closed to gather multiple optical fibers at the closing point, thereby facilitating installation and transfer.

[0046] In the embodiment of the present disclosure, a plurality of optical fiber adapter ports 31 are evenly arranged on the adapter plate 3 at least around the circumference. The peripheral arrangement can achieve regular entry into the inner channel of the drug column to avoid mutual influence.

[0047] In the embodiment of the present disclosure, a fiber optic adapter 31 is also provided at the center position of the adapter plate 3. The fiber optic adapter 31 at the center position is mainly used for obtaining images of the bottom of the large hole in the center of the drug column and the mouth of the drug column at the beginning.

[0048] In the embodiment of the present disclosure, the branch probe 4 includes an optical fiber adapter 41, a branch optical fiber 42, a camera 43, and an objective lens adapter 44, which are sequentially connected. The branch probe 4 is 200 mm long, the branch optical fiber 42 is 6.1 mm in diameter, has a tungsten braided layer on the outside, an optical fiber adapter 41 on the upper end, and a camera 43 and an objective lens adapter 44 on the lower end; the optical fiber adapter 41 is an ST optical fiber interface, and the ceramic ferrule diameter of the ST optical fiber interface is 2.499 mm; the image data taken by the camera 43 is transmitted to the optical fiber transmission component 2 by the ST optical fiber interface, and is stored by the handheld device 1; the objective lens adapter 44 includes a near-focus adapter and a far-focus adapter, and is made of titanium alloy.

[0049] In an embodiment of the present disclosure, the optical fiber transmission member 2 is composed of a plurality of optical fibers corresponding to the adapter plate 3; the outer layer of the optical fiber is a tungsten wire braided layer, and the optical fiber body is wrapped inside; one end of the optical fiber transmission member 2 is connected to the handheld device 1, and the other end is connected to the adapter plate 3. For example, the optical fiber has a length of 4.5 m, a diameter of 6.1 mm, and a tungsten wire braided layer on the outside, which is used to protect the electrical circuit and the optical fiber.

[0050] In an embodiment of the present disclosure, the adapter plate 3 has a cylindrical cavity structure and is made of titanium alloy. A plurality of optical fiber adapters 31 are buried in the adapter plate 3, and the optical fiber adapter 31 is an FC optical fiber interface; the adapter plate 3 adopts the FC protocol to transmit the image data captured by the branch probe 4 via the optical fiber transmission member 2. For example, the adapter plate 3 is a cylindrical structure with a diameter of 50 mm and a thickness of 50 mm, made of titanium alloy. The upper end is connected to the optical fiber transmission member 2, and there are nine FC optical fiber interfaces at the lower end. The interface diameter is 6.1 mm. An interface is also provided at the center of the adapter plate 3, and the circumferential interfaces are equally distributed on a circle with a radius of 15 mm centered on the central interface.

[0051] The method for detecting the inner surface of the solid propellant combined charge of the present invention is realized by using the device for detecting the inner surface of the solid propellant combined charge of the present invention, and includes the following steps:

[0052] Step 1: Install an unequal number of branch probes 4 according to the grain structure of the combined charge propellant;

[0053] Step 2: Take a photo above the star holes of the combined charge propellant and observe the damage condition of the star hole orifices;

[0054] Step 3: Insert the installed branch probes 4 and the adapter plate 3 into the center of the charge star holes and slowly push them inward. Observe the flaw detection condition on the handheld device 1 and mark the images;

[0055] Step 4: Take a photo of the bottom of the star holes of the combined charge propellant and observe the damage condition of the star hole bottoms; when defects are found in the conventional detection and close observation is required, change the telephoto lens to a close-up lens; store the taken pictures in the handheld device 1 and export them.

[0056] In addition, the obtained images are also judged for results, and the steps are as follows:

[0057] (1) Import the taken images into the image analysis software in JPG format. The pictures are black and white pictures with a gray scale distribution;

[0058] (2) The image analysis software automatically identifies the gray scale values of the pictures and judges the types of propellant defects, including cracks, pits, protrusions, scratches, as well as foreign objects and dirt;

[0059] The crack defect is a long strip defect with a width greater than 1 mm, and the gray level difference between the center line of the defect and 60% of the pixel points on the defect edge is more than 20, as Figure 6 shown;

[0060] The pit defect is a circular defect with a diameter greater than 1 mm, and the gray level of 60% of the pixel points in the defect is 30 or more higher than that of the defect edge, as Figure 7 shown;

[0061] The protrusion defect is a circular defect with a diameter greater than 1 mm, and the gray level of 60% of the pixel points in the defect is 30 or more smaller than that of the defect edge, as Figure 8 shown;

[0062] The scratch defect is a long strip defect with a width less than 1 mm, and the gray level difference between the center line of the defect and 60% of the pixel points on the defect edge is more than 20, as Figure 5 shown;

[0063] The foreign object defect is an irregular defect with an area greater than 2 mm 2 , and the gray level of 60% of the pixel points in the defect is 30 or more higher than that of the defect edge, as Figure 9 shown;

[0064] The dirt defect is an irregular defect with an area greater than 2 mm 2 , and the gray level of 60% of the pixel points in the defect is 30 or more smaller than that of the defect edge, as Figure 10 shown;

[0065] (3) The software exports the recognized results for secondary screening by humans; when a crack defect is detected on the inner surface, this propellant column is rejected (since the depth and direction of the crack are uncertain, when the propellant with crack defects is working, the burning surface will change greatly, seriously affecting the combustion performance of the propellant and even causing an engine disintegration and explosion accident, so when there are crack defects on the inner surface of the propellant, it is directly determined as unqualified); when pits, protrusions, and scratches are detected on the inner surface, according to the technical document requirements of the specific product, the number of various defects can be counted, and the size of the collected defect images can be measured for comprehensive result evaluation; when foreign objects or dirt are detected on the inner surface, first determine whether they can be cleaned. If they can be cleaned cleanly, there is no need to determine them as defects. If they cannot be cleaned, according to the technical document requirements of the specific product, the result evaluation is carried out.

[0066] Example 1:

[0067] The schematic diagram of the star hole structure of a certain composite charge propellant is as Figure 4 shown in a, which is an eight-tooth star hole charge structure and is used to test the multi-probe inner surface detection device and method of this patent.

[0068] The implementation device is carried out by using the inner surface detection device for solid propellant composite charges of the present invention;

[0069] The detection method includes the following steps:

[0070] Step 1: Standardize the numbering of the propellant to be inspected, identify it with a suitable method, clean the inner surface of the propellant to be inspected, keep it clean, and place it on the workbench.

[0071] Step 2: According to the grain structure of the large combined charge propellant in this embodiment, install the nine branch probes 4 on the adapter plate 3 and debug to confirm that the instrument is normal.

[0072] Step 3: Take a photo above the star hole of the combined charge propellant and observe the damage condition of the star hole orifice.

[0073] Step 4: Insert the installed branch probe 4 and the adapter plate 3 into the center of the charge star hole and slowly push it inward. Observe the flaw detection situation on the display screen of the handheld unit and mark the image.

[0074] Step 5: Take a photo of the bottom of the star hole of the combined charge propellant and observe the damage condition of the star hole bottom.

[0075] Step 6: When a defect is found during routine detection and close observation is required, change the long-focus lens of the objective lens adapter 44 to a short-focus lens.

[0076] Step 7: Store the taken pictures in the handheld unit and export them through a USB flash drive.

[0077] Step 8: Result judgment, the steps are as follows:

[0078] Import the taken photos into the image analysis software in JPG format, perform grayscale analysis and recognition, and the results are as follows:

[0079] There is 1 pit defect with a diameter of 0.5 mm, as Figure 7 shown.

[0080] There is 1 protrusion defect with a diameter of 3 mm, as Figure 8 shown.

[0081] Combined with the requirements of the technical document, the number and size of the defects are within the specified range, and it is judged as qualified.

[0082] Example 2:

[0083] The schematic diagram of the star hole structure of a certain combined charge propellant is as Figure 4 shown in b, which is a four-tooth star hole charge structure and is used to test the multi-probe inner surface detection device and method of this patent.

[0084] The results are as follows:

[0085] There is 1 crack defect with a length of 5 cm, asFigure 6 as shown

[0086] Combined with the requirements of the technical documents, if the number and size of defects are not within the specified range, it is determined as unqualified.

[0087] The above preferred embodiments are described in detail with reference to the accompanying drawings, which are not intended to limit the present invention. For each of the specific technical features described above, they can be combined in any suitable form without contradiction, and the present invention will not be elaborated one by one. Any person skilled in the art can, without departing from the scope of the technical solution, take means such as arbitrary combination or equivalent replacement of the technical solution, or make simple modifications or decorations, which do not affect the essence of the technical solution and still fall within the protection scope of the technical solutions represented by the embodiments of the present invention.

Claims

1. A device for detecting the inner surface of a solid propellant combined charge, characterized in that, A handheld device (1) is provided, and an optical fiber transmission component (2) for signal transmission is connected to the handheld device (1). A transfer disk (3) is provided at the end of the optical fiber transmission component (2), and at least one branch probe (4) is installed on the transfer disk (3). The transfer disk (3) is a disk member in which a plurality of optical fiber adapters (31) are embedded. At least circumferentially, a plurality of optical fiber adapters (31) are evenly provided on the transfer disk (3). An optical fiber adapter (31) is also provided at the center position of the transfer disk (3). The branch probe (4) includes an optical fiber adapter (41), a branch optical fiber (42), a camera (43), and an objective adapter (44) connected in sequence. The optical fiber adapter (41) is an ST optical fiber interface. The optical fiber transmission component (2) is composed of a plurality of optical fibers corresponding to the transfer disk (3); the outer layer of the optical fiber is a tungsten wire braided layer, and the optical fiber body is wrapped inside; one end of the optical fiber transmission component (2) is connected to the handheld device (1), and the other end is connected to the transfer disk (3). The transfer disk (3) is a cylindrical cavity structure made of titanium alloy. A plurality of optical fiber adapters (31) are embedded in the transfer disk (3), and the optical fiber adapters (31) are FC optical fiber interfaces. The transfer disk (3) adopts the FC protocol to transmit the image data captured by the branch probe (4) via the optical fiber transmission component (2).

2. A method for detecting the inner surface of a solid propellant combined charge, characterized in that, The method is implemented by using the inner surface detection device of the solid propellant combined charge described in claim 1, and includes the following steps: Step 1: Install an unequal number of branch probes (4) according to the grain configuration of the combined charge propellant. Step 2: Take a photo above the star holes of the combined charge propellant to observe the damage condition of the star hole orifices. Step 3: Insert the installed branch probes (4) and the transfer disk (3) into the center of the charge star holes and slowly push them inward, observe the flaw detection condition on the handheld device (1), and mark the images. Step 4: Take a photo of the bottom of the star holes of the combined charge propellant to observe the damage condition of the star hole bottoms; when defects are found in conventional inspections and close observations are required, change the telephoto lens to a close-up lens; store the captured pictures in the handheld device (1) and export them. The result determination of the obtained images is as follows: (1) Import the captured images into image analysis software in JPG format. The pictures are black and white pictures with a gray scale distribution. (2) The image analysis software automatically identifies the gray scale values of the pictures to judge the types of propellant defects, including cracks, pits, protrusions, scratches, as well as foreign objects and dirt. A crack defect is a long strip-shaped defect with a width greater than 1 mm, and the gray scale difference between the center line of the defect and 60% of the pixel points at the defect edge is more than 20. A pit defect is a circular defect with a diameter greater than 1 mm, and the gray scale of 60% of the pixel points in the defect is 30 or more higher than that at the defect edge. A protrusion defect is a circular defect with a diameter greater than 1 mm, and the gray scale of 60% of the pixel points in the defect is 30 or more smaller than that at the defect edge. A scratch defect is a long strip-shaped defect with a width less than 1 mm, and the gray scale difference between the center line of the defect and 60% of the pixel points at the defect edge is more than 20. Foreign object defect is an irregular defect with an area greater than 2 mm 2 , and the gray level of 60% of the pixels in the defect is more than 30 higher than that of the defect edge; The dirt defect is an irregular defect with an area larger than 2 mm 2 , and the gray level of 60% of the pixels in the defect is at least 30 less than that of the defect edge; (3)The software exports the recognized results for secondary screening by humans; when cracks are detected on the inner surface, this medicine delivery column is rejected; when pits, protrusions, and scratches are detected on the inner surface, the number of various defects can be counted according to the technical document requirements of the specific product, and the sizes of the collected defect images are measured for comprehensive result evaluation; when foreign objects or dirt are detected on the inner surface, first determine whether they can be cleaned. If they can be cleaned cleanly, they are not judged as defects. If they cannot be cleaned, result evaluation is carried out according to the technical document requirements of the specific product.

Images