Cross-linked cable eccentricity adjusting process and cross-linking production line thereof

Abstract

The invention discloses a crosslinked cable eccentricity adjusting process and a crosslinking production line thereof. The adjusting process comprises the following steps: S1, setting the number of cable extrusion layers; s2, setting a marking notch; s3, sampling the material and carrying out layer number sequence number calibration; s4, carrying out multi-layer co-extrusion and moving a crude product; s5, acquiring a thickness parameter set 1; s6, vulcanizing and cooling; s7, acquiring a thickness parameter set 2; s8, thickness solving is carried out, and xi is stored in a standard thickness parameter; s9, dynamically solving the thickness xi of each layer and performing time parameter derivation to obtain a trend derivative d1 and a trend derivative d2; and S10, judging a trend derivative d1 and a trend derivative d2, and carrying out feedback adjustment. By adopting the process, the thickness data of each layer can be accurately acquired, the deformation reason of the extrusion layer can be judged, the data acquisition mode is simpler, the acquisition cost is lower, the hysteresis of parameter adjustment can be effectively overcome, and the product yield is greatly improved.

Description

Technical Field

[0001] The invention relates to a cross-linked cable eccentricity adjustment process and a cross-linked production line thereof, belonging to the technical field of cable production. Background Art

[0002] Cables are important infrastructure in modern industry and daily life. They are widely used in power transmission, communication, data transmission, control signal transmission and other fields. Cable eccentricity is an important indicator that affects important performances such as cable impedance, capacitance imbalance performance, electromagnetic interference performance, stress, and thermal stability. In the cable production process, it is generally necessary to extrude the cross-linked polyethylene insulation shielding layer onto the conductor surface through head heating. After the cable passes through the vulcanizing tube, neutral tube and cooling tube, due to the influence of factors such as pipeline temperature, traction speed, cooling temperature, cable position (tension), etc., the eccentricity of the cable is still unknown. Before winding the cable, it is generally necessary to scan and inspect the cable cross section, and then make a judgment based on the scanning results, and adjust the production process according to the scanning results.

[0003] In the existing production process, the eccentricity scanning process is generally at the end of the production link and plays the role of finished product inspection. This process adjustment process is relatively long and requires special imported cross-sectional scanning equipment. This equipment is generally expensive, and due to factory settings, a separate adjustment system needs to be configured during the automated adjustment process. The adjustment process is long, the production line configuration cost is extremely high, and the technical level of production personnel is also required to be relatively high.

[0004] Furthermore, in the cable production process, it is often necessary to extrude multiple rubber layers. The above-mentioned cross-sectional scanning device can only scan the cross-sectional shape. In the cable co-extrusion process, due to the different performances of each layer, complex deformations such as interlayer torsion and inconsistent deformation of each layer will occur in the processing process. These problems make it impossible for simple cross-sectional scanning to timely determine the specific eccentricity of each layer of the cable, which brings greater difficulties to actual production. Summary of the invention

[0005] The purpose of the present invention is to provide a cross-linked cable eccentricity adjustment process and a cross-linked cable production line to solve the above technical problems.

[0006] The technical solution to achieve the purpose of the present invention is: a cross-linked cable eccentricity adjustment process for adjusting the extrusion speed of a cross-linked extruder and the cooling parameters of a cooling pipe, comprising the following steps:

[0007] S1: Set the number of cable extrusion layers;

[0008] S2: Setting the marking positions of different extrusion layers and setting the marking notches on the outermost extrusion die so that the extrusion layers get corresponding marking lines;

[0009] S3: Sampling different extrusion layer materials, using X-ray transmission instrument to measure the linear attenuation coefficient of the material and calibrating the layer number i;

[0010] S4: Multi-layer co-extrusion is performed to move the conductor-containing rough product along the production line;

[0011] S5: continuously collecting first thickness data at the cable extrusion outlet to obtain thickness parameter set 1;

[0012] S6: passing the crude product through the vulcanizing pipe, neutral pipe and cooling pipe in sequence;

[0013] S7: continuously collecting second thickness data at the cooling pipe outlet to obtain thickness parameter set 2;

[0014] S8: Solve the thickness according to thickness parameter set 1 and thickness parameter set 2 to obtain the thickness x of each layer i , and x i Stored as standard thickness parameters;

[0015] S9: According to parameter set 1 and thickness parameter set 2, x i Perform dynamic solution and calculate x i Derivative the time parameter to obtain the trend derivative d1 and trend derivative d2 respectively;

[0016] S10: Determine the values ​​of the trend derivative d1 and the trend derivative d2, and return the determined values ​​to the extrusion cross-linking extruder and the cooling pipe control device for reverse adjustment.

[0017] The above-mentioned cross-linked cable eccentricity adjustment process can accurately collect the thickness data of each extruded layer and determine the deformation cause of the extruded layer. Compared with the existing process, its data collection method is simpler, it does not need to use imported cross-sectional scanners, the collection cost is lower, and it can perform instant feedback adjustment at key deformation nodes, which can effectively overcome the lag of parameter adjustment and greatly improve product yield.

[0018] Further or optionally, in step S2, the inner layer of the extrusion die is a circle concentric with the conductor, the marking notch is an arc attached to the circumference, there are two arcs, and the line connecting the midpoints of the two arcs relative to the center of the conductor is perpendicular to each other.

[0019] The vertical design adopted in the above-mentioned marking gap design can effectively expand the parameter difference, thereby improving the accuracy of data collection, and separately disassemble each layer of data.

[0020] Further or optionally, the collection method of the thickness parameter set 1 and the thickness parameter set 2 in steps S5 and S7 is two-point penetration sampling.

[0021] And solve;

[0022] in:

[0023] i is the number of extrusion layers;

[0024] I is the X-ray intensity after penetration;

[0025] I0 is the initial X-ray intensity;

[0026] μ i is the linear attenuation coefficient of the ith material;

[0027] x i is the thickness of the ith material;

[0028] The two-point penetration sampling is defined as: aligning the X-ray transmission instrument with the marking line corresponding to the extruded marking notch, and performing continuous sampling along the marking line.

[0029] The above sampling method can be used to sample the thickness data of each layer separately; the significance of sampling along the marking line is that when deflection occurs, due to the inconsistency of the extrusion layer thickness corresponding to each part of the arc of the outer marking line, the thickness parameters obtained by sampling will change dramatically, thereby effectively amplifying the sensitivity of deflection data collection.

[0030] Further or optionally, the determination method in step S9 is:

[0031] When the trend derivative d1 and the trend derivative d2 are both constant at 0, no adjustment is performed;

[0032] When the trend derivative d1 is not equal to 0, the thickness parameter set 1 is retrieved, the trend of the data of the thickness parameter set 1 is determined and reversely adjusted;

[0033] When the trend derivative d2 is not equal to 0, the thickness parameter set 1 is called, the trend of the data of the thickness parameter set 2 is determined and reversely adjusted;

[0034] Compare the trend derivative d1 and the trend derivative d2. When the trend derivative d1=0 but d1≠0, it is determined that the extrusion has deflected at least in the middle section of the cooling process, and the relevant parameters affecting the deflection are adjusted.

[0035] The above determination method does not involve the cable cross-section modeling process, and the number of key parameters is small, which can effectively shorten the determination process and thus improve the sensitivity of parameter adjustment, accurately locate the cause of the fault and thus improve the accuracy of feedback adjustment.

[0036] Further or optionally, in order to obtain accurate deflection parameters, the method for determining the data trend derivative d1 and the trend derivative d2 of the thickness parameter set 1 and the thickness parameter set 2 is:

[0037] Compare 3 to 5 consecutive sampling point data x i 'Size, when xi 'With standard thickness parameter x i If there is any inconsistency, scan the cable circumferentially and collect x i 'Corresponding to the scanning angle, x at different time points i ' and angle data are incorrect. When the angle does not change, it is judged as uneven thickness and the thickness affecting parameters are adjusted; when the angle deflects, the deflection affecting parameters are adjusted.

[0038] In order to improve the yield rate of cross-linked cables, the present application also proposes a cross-linked cable production line, which adopts any of the above-mentioned eccentricity adjustment processes, and specifically includes a cross-linking extruder, a first X-ray transmission instrument, a vulcanizing tube, a neutral tube, a cooling tube, a second X-ray transmission instrument, a cable winding machine, and a feedback adjustment system for controlling the aforementioned equipment.

[0039] Further or optionally, in order to reduce the energy consumption of the cable winding machine, in the above-mentioned cross-linked cable production line, the cross-linking extruder, the first X-ray transmission instrument, the vulcanizing tube, the neutral tube, the cooling tube, and the second X-ray transmission instrument are laid on one platform, and the cable winding machine is laid on another platform. There is a height difference between the two and the cable winding machine is lower than the second X-ray transmission instrument, and a ramp transition is adopted between the two in time.

[0040] The above structure can be referred to as a catenary structure, which can effectively utilize the gravity of the cable itself and reduce the energy consumption of the cable winding machine.

[0041] By adopting the above technical solution, the present invention has the following beneficial effects:

[0042] (1) The cross-linked cable eccentricity adjustment process of the present application can accurately collect the thickness data of each extruded layer and determine the deformation cause of the extruded layer. Compared with the existing process, its data collection method is simpler and does not require the use of imported cross-sectional scanners. The collection cost is lower and instant feedback adjustment can be performed at key deformation nodes, which can effectively overcome the lag of parameter adjustment and greatly improve product yield.

[0043] (2) The vertical design used in the marking notch design of the present application can effectively expand the parameter difference and thus improve the accuracy of data collection.

[0044] (3) The sampling method of the present application can sample the thickness data of each layer separately; the significance of sampling along the marking line is that when deflection occurs, since the thickness of the extruded layer corresponding to each part of the arc of the marking line is inconsistent, the thickness parameter obtained by sampling will change dramatically, thereby effectively amplifying the sensitivity of deflection data collection.

[0045] (4) The key parameter determination method of the present application does not involve the cable cross-section modeling process. The number of key parameters is small, which can effectively shorten the determination process and thus improve the sensitivity of parameter adjustment, accurately locate the cause of the fault and thus improve the accuracy of feedback adjustment.

[0046] (5) The present application can obtain accurate deflection parameters under the premise of compressing the number of samples.

[0047] (6) The present application also provides a cross-linked cable production line that can perform rapid feedback adjustment and significantly improve the yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments and in conjunction with the accompanying drawings, wherein

[0049] Figure 1 It is a flow chart of the adjustment method of the present invention.

[0050] Figure 2 It is a schematic diagram of the device connection relationship of the present invention. DETAILED DESCRIPTION

[0051] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0052] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0053] All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0054] (Example 1)

[0055] A cross-linked cable eccentricity adjustment process according to this embodiment, wherein the specific adjustment method is as follows: Figure 1 As shown, the specific steps include:

[0056] S1: Set the number of cable extrusion layers;

[0057] S2: Setting the marking positions of different extrusion layers and setting the marking notches on the outermost extrusion die so that the extrusion layers get corresponding marking lines;

[0058] S3: Sampling different extrusion layer materials, using X-ray transmission instrument to measure the linear attenuation coefficient of the material and calibrating the layer number i;

[0059] S4: Multi-layer co-extrusion is performed to move the conductor-containing rough product along the production line;

[0060] S5: continuously collecting first thickness data at the cable extrusion outlet to obtain thickness parameter set 1;

[0061] S6: passing the crude product through the vulcanizing pipe, neutral pipe and cooling pipe in sequence;

[0062] S7: continuously collecting second thickness data at the cooling pipe outlet to obtain thickness parameter set 2;

[0063] S8: Solve the thickness according to thickness parameter set 1 and thickness parameter set 2 to obtain the thickness x of each layer i , and x i Stored as standard thickness parameters;

[0064] S9: According to parameter set 1 and thickness parameter set 2, x i Perform dynamic solution and calculate x i Derivative the time parameter to obtain the trend derivative d1 and trend derivative d2 respectively;

[0065] S10: Determine the values ​​of the trend derivative d1 and the trend derivative d2, and return the determined values ​​to the extrusion cross-linking extruder and the cooling pipe control device for reverse adjustment.

[0066] In step S2, the inner layer of the extrusion die is a circle concentric with the conductor, the marking notch is an arc attached to the circumference, there are two arcs, and the line connecting the midpoints of the two arcs relative to the center of the conductor is perpendicular to each other.

[0067] The collection method of thickness parameter set 1 and thickness parameter set 2 in steps S5 and S7 is two-point penetration sampling.

[0068] And solve;

[0069] in:

[0070] i is the number of extrusion layers;

[0071] I is the X-ray intensity after penetration;

[0072] I0 is the initial X-ray intensity;

[0073] μ i is the linear attenuation coefficient of the ith material;

[0074] x i is the thickness of the ith material;

[0075] The two-point penetration sampling is defined as: aligning the X-ray transmission instrument with the marking line corresponding to the extruded marking notch, and performing continuous sampling along the marking line.

[0076] The determination method in step S9 is:

[0077] When the trend derivative d1 and the trend derivative d2 are both constant at 0, no adjustment is performed;

[0078] When the trend derivative d1 is not equal to 0, the thickness parameter set 1 is retrieved, the trend of the data of the thickness parameter set 1 is determined and reversely adjusted;

[0079] When the trend derivative d2 is not equal to 0, the thickness parameter set 1 is called, the trend of the data of the thickness parameter set 2 is determined and reversely adjusted;

[0080] Compare the trend derivative d1 and the trend derivative d2. When the trend derivative d1=0 but d1≠0, it is determined that the extrusion has deflected at least in the middle section of the cooling process, and the relevant parameters affecting the deflection are adjusted.

[0081] The method for determining the data trend derivative d1 and trend derivative d2 of thickness parameter set 1 and thickness parameter set 2 is:

[0082] Compare 3 to 5 consecutive sampling point data x i 'Size, when x i 'With standard thickness parameter x i If there is any inconsistency, scan the cable circumferentially and collect x i 'Corresponding to the scanning angle, x at different time points i ' and angle data are incorrect. When the angle does not change, it is judged as uneven thickness and the thickness affecting parameters are adjusted; when the angle deflects, the deflection affecting parameters are adjusted.

[0083] A cross-linked cable production line adopts a catenary structure and the above-mentioned eccentricity adjustment process, wherein the cross-linked extruder, the first X-ray transmission instrument, the vulcanizing tube, the neutral tube, the cooling tube, the second X-ray transmission instrument, the cable winding machine, and the feedback adjustment system for controlling the above-mentioned devices are connected in sequence, and the specific device connection method is as follows Figure 2 shown.

[0084] By adopting the above cross-linked cable eccentricity adjustment process, the product yield can be increased from 90% to 97%.

[0085] It should be understood that the present invention is described by some embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the scope of protection of the present invention.

Claims

1. A cross-linked cable eccentricity adjustment process, used to adjust the extrusion speed of a cross-linked extruder and the cooling parameters of a cooling tube, characterized in that: The steps include: S1: Set the number of cable extrusion layers; S2: Setting the marking positions of different extrusion layers and setting the marking notches on the outermost extrusion die so that the extrusion layers get corresponding marking lines; S3: Sampling different extrusion layer materials, using X-ray transmission instrument to measure the linear attenuation coefficient of the material and calibrating the layer number i; S4: Multi-layer co-extrusion is performed to move the conductor-containing rough product along the production line; S5: continuously collecting first thickness data at the cable extrusion outlet to obtain thickness parameter set 1; S6: passing the crude product through the vulcanizing pipe, neutral pipe and cooling pipe in sequence; S7: continuously collecting second thickness data at the cooling pipe outlet to obtain thickness parameter set 2; S8: Solve the thickness according to thickness parameter set 1 and thickness parameter set 2 to obtain the thickness x of each layer i , and x i Stored as standard thickness parameters; S9: According to parameter set 1 and thickness parameter set 2, x i Perform dynamic solution and calculate x i Derivative the time parameter to obtain the trend derivative d1 and trend derivative d2 respectively; S10: Determine the values ​​of the trend derivative d1 and the trend derivative d2, and return the determined values ​​to the extrusion cross-linking extruder and the cooling pipe control device for reverse adjustment.

2. A cross-linked cable eccentricity adjustment process according to claim 1, characterized in that: In step S2, the inner layer of the extrusion die is a circle concentric with the conductor, the marking notch is an arc attached to the circumference, there are two arcs, and the line connecting the midpoints of the two arcs relative to the center of the conductor is perpendicular to each other.

3. A cross-linked cable eccentricity adjustment process according to claim 1, characterized in that: The collection method of thickness parameter set 1 and thickness parameter set 2 in steps S5 and S7 is two-point penetration sampling. I i =I0e - (+μ i x i +μ i x i ) and solve; in: i is the number of extrusion layers; I is the X-ray intensity after penetration; I0 is the initial X-ray intensity; μ i is the linear attenuation coefficient of the ith material; x i is the thickness of the ith material; The two-point penetration sampling is defined as: aligning the X-ray transmission instrument with the marking line corresponding to the extruded marking notch, and performing continuous sampling along the marking line.

4. A cross-linked cable eccentricity adjustment process according to claim 1, characterized in that: The determination method in step S9 is: When the trend derivative d1 and the trend derivative d2 are both constant at 0, no adjustment is performed; When the trend derivative d1 is not equal to 0, the thickness parameter set 1 is retrieved, the trend of the data of the thickness parameter set 1 is determined and reversely adjusted; When the trend derivative d2 is not equal to 0, the thickness parameter set 1 is called, the trend of the data of the thickness parameter set 2 is determined and reversely adjusted; Compare the trend derivative d1 and the trend derivative d2. When the trend derivative d1=0 but d1≠0, it is determined that the extrusion has deflected at least in the middle section of the cooling process, and the relevant parameters affecting the deflection are adjusted.

5. A cross-linked cable eccentricity adjustment process according to claim 4, characterized in that The method for determining the data trend derivative d1 and trend derivative d2 of thickness parameter set 1 and thickness parameter set 2 is: Compare 3 to 5 consecutive sampling point data x i 'Size, when x i 'With standard thickness parameter x i If there is any inconsistency, scan the cable circumferentially and collect x i 'Corresponding to the scanning angle, x at different time points i ' and angle data are incorrect. When the angle does not change, it is judged as uneven thickness and the thickness affecting parameters are adjusted; when the angle deflects, the deflection affecting parameters are adjusted.

6. A cross-linked cable production line, characterized in that: It adopts the eccentricity adjustment process described in any one of claims 1 to 5, and specifically comprises a cross-linking extruder, a first X-ray transmission device, a vulcanizing tube, a neutral tube, a cooling tube, a second X-ray transmission device, a cable winding machine, and a feedback adjustment system for controlling the aforementioned devices.

7. A cross-linked cable production line according to claim 6, characterized in that: The cross-linking extruder, the first X-ray transmissometer, the vulcanizing tube, the neutral tube, the cooling tube and the second X-ray transmissometer are laid on one platform, and the cable winder is laid on another platform. There is a height difference between the two and the cable winder is lower than the second X-ray transmissometer, and a ramp transition is used between the two.

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