Device for equalizing wall thickness of large-diameter seamless stainless steel pipe

Abstract

The present application relates to wall thickness processing device technical field, specifically disclose equal wall thickness processing device of large diameter seamless stainless steel pipe, including: base, stand, cutting assembly, control management unit, the base is fixedly connected with support plate, the support plate is V-shaped structure, the outside of support plate is rotatably connected with multiple groups of ball, the stand is fixedly connected on base, the stand is equipped with drive assembly, the drive assembly is used for driving the rotation of pipeline on support plate, the cutting assembly is set on base, is used for cutting to steel pipe, the control management unit controls cutting assembly, also carries out diameter and wall thickness detection to pipeline, completes wall thickness deviation calculation. The present application effectively solves the problem of low automation degree, insufficient precision of traditional equipment, improves the quality and efficiency of wall thickness processing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wall thickness processing devices, in particular to an equal wall thickness processing device for large-diameter seamless stainless steel pipes. BACKGROUND

[0002] In the modern industrial field, large-diameter seamless stainless steel pipes are widely used in key industries such as petroleum and chemical industry, water conservancy engineering, power transmission, aerospace, etc. due to their excellent corrosion resistance, high strength and good sealing performance. These application scenarios have high requirements for the quality of large-diameter seamless stainless steel pipes, and the uniformity of pipe wall thickness is one of the core indicators for measuring the quality of the pipes. However, during the production and manufacturing process of large-diameter seamless stainless steel pipes, due to the influence of various factors, the problem of uneven pipe wall thickness often occurs, thus requiring a wall thickness processing device.

[0003] The traditional large-diameter seamless stainless steel pipe wall thickness processing device has many limitations in dealing with the above problems. The automation degree of the traditional device is low, and most of the adjustment and control rely on manual operation, which not only has low efficiency, but also has difficulty in ensuring the processing accuracy, and is easily affected by human factors, resulting in unstable product quality. SUMMARY

[0004] In view of the technical problems that the existing stainless steel pipe wall thickness processing device mostly relies on manual operation for adjustment and control, which not only has low efficiency, but also has difficulty in ensuring the processing accuracy, the present application provides an equal wall thickness processing device for large-diameter seamless stainless steel pipes.

[0005] The technical solution adopted by the present application is: an equal wall thickness processing device for large-diameter seamless stainless steel pipes, comprising:

[0006] a base, the base is fixedly connected with a support plate, the support plate is a V-shaped structure, and the outer part of the support plate is rotatably connected with a plurality of groups of ball bearings;

[0007] a stand, the stand is fixedly connected to the base, and the stand is provided with a driving assembly, the driving assembly is used to drive the pipe on the support plate to rotate;

[0008] a cutting assembly, the cutting assembly is arranged on the base and is used to cut the steel pipe;

[0009] a control management unit, the control management unit controls the cutting assembly and also detects the diameter and wall thickness of the pipe in all directions to complete the wall thickness deviation calculation.

[0010] The further setting of the application is that the driving assembly comprises a first motor and friction wheels, the friction wheels are provided with two groups and are rotatably connected to the two sides of the mounting seat, the first motor is fixedly connected to the outside of the mounting seat, the output end of the first motor is fixedly connected with the friction wheels, a first cylinder is fixedly connected to the stand, and the output end of the first cylinder is fixedly connected with the mounting seat

[0011] The further setting of the application is that a second cylinder is fixedly connected to the base, the output end of the second cylinder is fixedly connected with a lifting plate, the top of the lifting plate is fixedly connected with a second motor on both sides, the output end of the second motor is fixedly connected with a first threaded rod, the outside of the first threaded rod is threadedly connected with a first nut block, the top of the lifting plate is fixedly connected with a first limiting rod, the first limiting rod penetrates through the first nut block, the top of the first nut block is rotatably connected with a rotating roller, and the bottom of the supporting plate is provided with a first sliding opening, and the rotating roller penetrates through the first sliding opening.

[0012] The further setting of the application is that the outside of the stand is fixedly connected with a side frame, the outside of the side frame is fixedly connected with a third motor, the output end of the third motor is fixedly connected with a second threaded rod, the outside of the second threaded rod is threadedly connected with a second nut block, the outside of the side frame is provided with a second sliding opening, the second nut block is slidably connected in the second sliding opening, and the outside of the second nut block is fixedly connected with an ultrasonic probe.

[0013] The further setting of the application is that the cutting assembly comprises a moving frame and a cutting tool fixedly connected to the outside of the moving frame, a fixed frame is fixedly connected to the base, the outside of the fixed frame is fixedly connected with a servo motor, the output end of the servo motor is fixedly connected with a third threaded rod, the outside of the third threaded rod is threadedly connected with a third nut block, the outside of the fixed frame is fixedly connected with a second limiting rod, the second limiting rod penetrates through the third nut block, and the outside of the third nut block is fixedly connected with an electric push rod, and the output end of the electric push rod is fixedly connected with the moving frame.

[0014] The further setting of the application is that a rotating speed sensor is further fixedly installed on the supporting plate.

[0015] The further setting of the application is that the control management unit comprises a control system, a pipeline detection module, a wall thickness adjustment module and a quality detection module, and the rotating speed sensor, the pipeline detection module, the wall thickness adjustment module and the quality detection module are controlled by the control system.

[0016] The further setting of the application is that the pipeline detection module carries out multi-point measurement on the outer diameter, the inner diameter and the wall thickness geometric parameters of the pipeline through an ultrasonic detection probe, carries out wall thickness deviation calculation, material performance parameter detection and data analysis and processing at the same time.

[0017] Wherein, the distribution of measuring points should evenly cover the whole length and circumferential direction of the pipeline;

[0018] Suppose the nominal outer diameter of the pipeline is D0, the nominal inner diameter is d0, and the nominal wall thickness is t0, wherein t0=(D0-d0) / 2;

[0019] In the measurement, the outer diameter of each measuring point of the pipeline is D i , i=1, 2, …, n, n is the total number of measuring points, the inner diameter is d i , and the actual wall thickness of each point is t i =(D i -d i ) / 2;

[0020] Calculate the wall thickness deviation:

[0021] According to the actual wall thickness t i obtained by measurement, the wall thickness deviation of each point is calculated, and the wall thickness deviation Δt i is defined as the difference between the actual wall thickness and the nominal wall thickness, that is:

[0022] Δt i =t i -t0;

[0023] At the same time, the maximum wall thickness deviation Δt max and the minimum wall thickness deviation Δt min are calculated, that is:

[0024] Δt max =max(Δt i );

[0025] Δt min =min(Δt i );

[0026] Calculate the wall thickness deviation rate η i , the formula is:

[0027] η i =(Δt i / t0)×100%;

[0028] Material performance parameter detection:

[0029] The mechanical properties of the pipeline material are detected, including yield strength σ s , tensile strength σ b , elastic modulus E, Poisson's ratio μ, etc.

[0030] Data analysis and processing:

[0031] The measured geometric parameters and material performance parameters are organized and analyzed, and wall thickness distribution curves and wall thickness deviation curves are plotted to identify the areas and degrees of uneven pipe wall thickness. Based on the analysis results, it is determined whether the pipe needs to be treated with equal wall thickness and to identify the key areas for treatment. If the absolute value of the maximum wall thickness deviation rate exceeds the preset allowable range (e.g., 5%), then equal wall thickness treatment of the pipe is required.

[0032] A further provision of the present invention is that the wall thickness adjustment module includes calculating the wall thickness adjustment amount and selecting processing parameters;

[0033] Wall thickness adjustment calculation:

[0034] For areas with thicker walls, the excess wall thickness needs to be removed by cutting.

[0035] Let the target wall thickness be t. target For areas where wall thickness needs to be removed, the theoretical removal amount δ i理论 ;

[0036] δ i理论 =t i -t target ;

[0037]

[0038] Where, λ i k1 is the wall thickness correction coefficient for the i-th measurement point; k2 is the wall thickness deviation influence coefficient, obtained through fitting experimental data, with a value range of 0.01-0.05; k3 is the cutting speed and elastic modulus influence coefficient, with a value range of 10. -6 -5×10 -6 ; The dimensions of k2 and The dimensions of k2 and k2 are reciprocals of each other, that is, the dimension of k2 is M·L. -2 ·T -1 k3 is the influence coefficient between feed rate and actual wall thickness, with a value range of 0.1-0.5; Δt i Let v be the wall thickness deviation at the i-th measurement point; v is the cutting speed, with dimensions L·T. -1 E is the elastic modulus, with dimensions M·L. -1 ·T -2 f is the feed rate; t i The actual wall thickness at the i-th measurement point;

[0039] Corrected actual removal amount δ i for:

[0040] δ i =δ i理论 ×λ i ;

[0041] For the thin-walled pipe subjected to internal pressure, the wall thickness calculation formula is:

[0042]

[0043] Wherein, t is the calculated wall thickness, p is the design internal pressure, D is the pipe inner diameter, σ allow is the allowable stress of the material, when determining the target wall thickness t target , it is ensured that it meets the above strength condition, that is, t target ≥t;

[0044] Processing parameter selection:

[0045] The determined process parameters include cutting speed v, feed amount f, cutting depth a p , the calculation formula of cutting speed v is:

[0046]

[0047] Wherein, D is the diameter of the pipe during turning, n is the speed of the pipe, the feed amount f refers to the distance that the cutting tool moves along the feed direction per revolution of the pipe, and the cutting depth a p refers to the depth of the cutting tool cutting into the pipe, in the wall thickness processing, a p is equal to or less than the wall thickness removal amount δ i ;

[0048] Design cutting force prediction formula:

[0049]

[0050] Wherein, F c is the main cutting force, the dimension is M·L·T -2 ; C F is the cutting force coefficient, which is related to the tool material and the workpiece material, for stainless steel material and hard alloy cutting tool, the value range is 500-800; x F is the cutting depth index, the value range is 0.8-1.0; y F is the feed amount index, the value range is 0.6-0.8; n F is the cutting speed index, the value is 0; m F is the tensile strength index, the value is 1; p F is the wall thickness correction coefficient index, the value range is 0.2-0.4; a is the cutting depth; f is the feed amount; v is the cutting speed; σ b is the tensile strength of the pipe; λ i is the wall thickness correction coefficient of the ith measuring point; and x F +y F =2.

[0051] Finite element analysis software was used to simulate and analyze the processing, a three-dimensional finite element model of the pipeline was established, material properties, boundary conditions and load parameters were set, and the stress-strain distribution and temperature field changes of the pipeline under different processing parameters were simulated.

[0052] A further provision of the present invention is that the quality inspection module performs quality inspection on the pipe after wall thickness treatment, and performs wall thickness accuracy inspection.

[0053] Wall thickness accuracy inspection:

[0054] The thickness of the pipe wall after treatment was measured again using an ultrasonic probe.

[0055] Calculate the actual wall thickness t′ at each measurement point. i With target wall thickness t target Deviation;

[0056] Where, Δt′ i =t′ i -t target ;

[0057] And calculate the maximum deviation Δt′ max and minimum deviation Δt′ min and deviation rate η′ i ;

[0058] η′ i =(Δt′) i / t target )×100%;

[0059] The absolute value of the wall thickness deviation rate after processing does not exceed the preset allowable range; otherwise, secondary processing is required.

[0060] The beneficial effects of this invention are as follows: This invention effectively solves the problems of low automation and insufficient precision in traditional equipment, comprehensively improving the quality and efficiency of wall thickness processing; by using a support plate in conjunction with ball bearings to reduce friction, it achieves stable support and precise positioning of the pipeline, avoiding the shaking problem caused by traditional manual fixing. The drive component enables the pipeline to rotate smoothly, replacing the cumbersome process of traditional manual adjustment, ensuring uniform force and stable rotation of the pipeline during processing. The control and management unit performs comprehensive diameter and wall thickness detection of the pipeline, completing tasks such as wall thickness deviation calculation and material performance analysis, providing accurate data support for cutting, and eliminating the lag and error of traditional manual detection. The cutting component can perform targeted cutting on areas with wall thickness deviation. Attached Figure Description

[0061] Figure 1 This is a schematic diagram of the structure of the present invention;

[0062] Figure 2 yes Figure 1The enlarged structural schematic diagram of the middle A area;

[0063] Figure 3 The structural schematic diagram of the base in the application;

[0064] Figure 4 The structural schematic diagram of the first nut block in the application;

[0065] Figure 5 The structural schematic diagram of the support plate in the application;

[0066] Figure 6 The structural schematic diagram of the cutting assembly in the application.

[0067] The figure is marked as:

[0068] 1, base; 2, stand; 3, first air cylinder; 4, mounting seat; 5, friction wheel; 6, first motor; 7, support plate; 8, ball; 9, first sliding port; 10, second air cylinder; 11, lifting plate; 12, second motor; 13, first threaded rod; 14, first limiting rod; 15, first nut block; 16, rotating roller; 17, third motor; 18, second threaded rod; 19, second nut block; 20, side frame; 21, second sliding port; 22, ultrasonic probe; 23, fixing frame; 24, third threaded rod; 25, second limiting rod; 26, third nut block; 27, electric push rod; 28, moving frame; 29, cutting tool. DETAILED DESCRIPTION

[0069] In the description of the application, it should be noted that the terms "front", "upper", "lower", "left", "right", "vertical", "horizontal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0070] The following will be described in conjunction with the accompanying Figures 1-6 The application is further described.

[0071] Example one:

[0072] In order to solve the problems in the background art, the technical scheme is proposed as follows: the equal wall thickness processing device for large-diameter seamless stainless steel pipe comprises a base 1, a stand 2, a cutting assembly, and a control management unit. The base 1 is fixedly connected with a support plate 7, which is in a V-shaped structure. A plurality of groups of rolling balls 8 are rotatably connected to the outside of the support plate 7. The stand 2 is fixedly connected to the base 1 and is provided with a driving assembly for driving the pipe on the support plate 7 to rotate. The cutting assembly is arranged on the base 1 and is used for cutting the steel pipe. The control management unit controls the cutting assembly and also detects the diameter and wall thickness of the pipe in all directions to complete the wall thickness deviation calculation. The base 1 serves as the foundation of the entire device and provides stable mounting support for each component to ensure stable operation of the equipment during the processing. The V-shaped support plate 7 can fit the arc-shaped outer wall of the large-diameter seamless stainless steel pipe and stably hold the pipe from below to prevent the pipe from shaking or deviating during processing. The plurality of groups of rolling balls 8 on the outside of the support plate 7 can reduce the friction between the pipe and the support plate 7. When the pipe rotates, the rolling balls 8 roll along with it, reducing the risk of wear on the surface of the pipe and allowing the pipe to rotate more smoothly.

[0073] The stand 2 is fixed to the base 1 and provides a mounting carrier for the driving assembly. The driving assembly drives the pipe to rotate, allowing the cutting assembly to uniformly process the pipe in the circumferential direction. The cutting assembly is responsible for accurately cutting the wall thickness of the steel pipe to achieve equal wall thickness processing. The control management unit is the core control part of the device. It analyzes the real-time detection data of the pipe and accurately controls the action of the cutting assembly to ensure that the wall thickness of the cut pipe is uniform and meets the processing precision requirements. The overall structure has clear division of labor, forming a complete process from pipe support, driving to detection and cutting, providing reliable protection for equal wall thickness processing of large-diameter seamless stainless steel pipes.

[0074] In this embodiment, the driving assembly includes a first motor 6 and a friction wheel 5. The friction wheel 5 is provided with two groups, which are rotatably connected to the two sides of the mounting seat 4. The first motor 6 is fixedly connected to the outside of the mounting seat 4. The output end of the first motor 6 is fixedly connected with the friction wheel 5. The stand 2 is fixedly connected with a first air cylinder 3. The output end of the first air cylinder 3 is fixedly connected with the mounting seat 4. When the pipe needs to be driven to rotate, the first air cylinder 3 pushes the mounting seat 4 to move downward, so that the friction wheel 5 tightly abuts against the outer wall of the pipe to ensure sufficient friction. After processing is completed, the first air cylinder 3 drives the mounting seat 4 to rise, and the friction wheel 5 is separated from the pipe, facilitating the taking and placing of the pipe. This pneumatic control mode is flexible to operate and can quickly realize the contact and separation of the friction wheel 5 and the pipe. The contact force can be adjusted by the pressure of the air cylinder to avoid damaging the surface of the pipe due to excessive pressure or causing slipping due to insufficient pressure, ensuring stable and reliable rotation of the pipe.

[0075] In this embodiment, the base 1 is fixedly connected with the second cylinder 10, the output end of the second cylinder 10 is fixedly connected with the lifting plate 11, the top of the lifting plate 11 is fixedly connected with the second motor 12 on both sides, the output end of the second motor 12 is fixedly connected with the first threaded rod 13, the first threaded rod 13 is externally threaded with the first nut block 15, the top of the lifting plate 11 is fixedly connected with the first limiting rod 14, the first limiting rod 14 penetrates through the first nut block 15, and the top of the first nut block 15 is rotatably connected with the rotating roller 16. The bottom of the supporting plate 7 is provided with the first sliding port 9, and the rotating roller 16 penetrates through the first sliding port 9. The second cylinder 10 on the base 1 drives the lifting plate 11 to move up and down through the telescopic belt, and then adjusts the height position of the rotating roller 16. The second motor 12 on both sides of the top of the lifting plate 11 provides power for the position adjustment of the rotating roller 16. When the first threaded rod 13 connected with the output end of the motor rotates, the first nut block 15 externally threaded with the threaded rod will move along the axial direction of the threaded rod. The first limiting rod 14 penetrates through the first nut block 15, limits the rotation of the nut block with the threaded rod, ensures that the nut block only moves linearly, and guarantees the moving direction of the rotating roller 16 to be accurate.

[0076] The rotating roller 16 rotatably connected with the top of the nut block penetrates through the first sliding port 9 in the bottom of the supporting plate 7 and can contact the side wall of the pipeline. The threaded rod is driven to rotate by the second motor 12, the distance between the rotating rollers 16 on both sides can be adjusted, the rotating roller 16 is tightly abutted against the side wall of the pipeline, the pipeline is fixed and limited from both sides, the V-shaped supporting plate 7 below is matched, a three-point positioning structure is formed, the stability of the pipeline in the self-rotation process is further enhanced, the radial deviation or jumping of the pipeline is prevented, and the accuracy of subsequent cutting processing is guaranteed. The height adjustment of the lifting plate 11 can adapt to pipelines with different diameters and improve the universality of the device.

[0077] In this embodiment, the outer side of the stand 2 is fixedly connected with the side frame 20, the outer side of the side frame 20 is fixedly connected with the third motor 17, the output end of the third motor 17 is fixedly connected with the second threaded rod 18, the outer side of the second threaded rod 18 is externally threaded with the second nut block 19, the outer side of the side frame 20 is provided with the second sliding port 21, the second nut block 19 is slidingly connected in the second sliding port 21, and the outer side of the second nut block 19 is fixedly connected with the ultrasonic probe 22; the side frame 20 outside the stand 2 provides mounting support for the detection assembly, the third motor 17 drives the second threaded rod 18 to rotate, and the second nut block 19 externally threaded with the threaded rod moves along the threaded rod. The second sliding port 21 outside the side frame 20 guides and limits the second nut block 19, ensures that the nut block slides stably, and avoids shaking to affect the detection accuracy.

[0078] The ultrasonic probe 22 outside the second nut block 19 moves with the nut block and can scan and detect the pipe surface in multiple directions. The ultrasonic probe 22 can accurately measure the diameter and wall thickness of the pipe. The third motor 17 is driven to realize axial movement along the pipe, and in combination with the self-rotation of the pipe, the uniform detection of the entire surface of the pipe can be completed, and comprehensive wall thickness data can be obtained. This moving detection method can cover every area of the pipe, avoid detection blind spots, provide accurate raw data for the control management unit, and ensure that the subsequent cutting process can be targeted to handle the wall thickness deviation parts.

[0079] In the embodiment, the cutting assembly includes a moving frame 28 and a cutting tool 29 fixedly connected outside the moving frame 28. A fixed frame 23 is fixedly connected to the base 1. A servo motor is fixedly connected outside the fixed frame 23. A third threaded rod 24 is fixedly connected to the output end of the servo motor. A third nut block 26 is threadedly connected to the outside of the third threaded rod 24. A second limiting rod 25 is fixedly connected outside the fixed frame 23 and penetrates the third nut block 26. An electric push rod 27 is fixedly connected to the outside of the third nut block 26. The output end of the electric push rod 27 is fixedly connected to the moving frame 28. The cutting tool 29 in the cutting assembly is fixed to the moving frame 28 and is an execution component for cutting the pipe wall thickness. The fixed frame 23 on the base 1 provides a mounting basis for the adjustment structure of the cutting assembly. The servo motor drives the third threaded rod 24 to rotate, so that the third nut block 26 outside moves along the threaded rod. The second limiting rod 25 penetrates the nut block to ensure stable linear motion without deviation.

[0080] The electric push rod 27 outside the third nut block 26 can drive the moving frame 28 and the cutting tool 29 to move radially and accurately adjust the distance between the cutting tool 29 and the pipe surface. The axial movement driven by the servo motor and the radial movement driven by the electric push rod 27 are combined, so that the cutting tool 29 can perform cutting work at any position on the pipe surface. The servo motor has high-precision control characteristics and can accurately control the movement distance of the cutting tool 29. The electric push rod 27 can accurately adjust the cutting depth. The combination of the two ensures accurate and controllable cutting process, realizes uniform processing of the pipe wall thickness, and meets the precision requirements of equal wall thickness.

[0081] The use method of the embodiment is as follows:

[0082] When using the device, first place the large-diameter seamless stainless steel pipe to be processed on the V-shaped support plate 7, and the ball bearings 8 of the support plate 7 reduce friction when placing. Start the first air cylinder 3 to drive the mounting seat 4 and the friction wheel 5 to move downward, so that the friction wheel 5 tightly abuts against the outer wall of the pipe to provide driving force for the self-rotation of the pipe. Then start the second air cylinder 10, and the lifting plate 11 rises to drive the rotating rollers 16 to pass through the first sliding port 9. Then, the first threaded rod 13 is driven to rotate by the second motor 12, the positions of the rotating rollers 16 on both sides are adjusted, the rotating rollers 16 abut against the pipe from both sides, and the support plate 7 forms stable clamping to prevent the pipe from deviating when rotating.

[0083] Subsequently, the second threaded rod 18 is driven to rotate by the third motor 17, the ultrasonic probe 22 is moved along the side frame 20 by the second nut block 19, and the pipe is detected in all directions in terms of diameter and wall thickness in combination with the subsequent self-rotation of the pipe. The detection data is transmitted to the control management unit in real time. After detection is completed, the first motor 6 is started, and the friction wheel 5 is rotated to drive the pipe to stably self-rotate by friction.

[0084] Finally, the third threaded rod 24 is driven to rotate by the servo motor, the third nut block 26 drives the cutting tool 29 to move along the axial direction of the pipe, and the radial position of the cutting tool 29 is adjusted by the electric push rod 27. According to the detection data, the pipe wall thickness deviation part is precisely cut to realize equal wall thickness processing. The entire process has high automation degree, and is continuously performed from fixing, detection to cutting, which ensures machining precision and efficiency.

[0085] Embodiment two:

[0086] The support plate 7 is also fixedly installed with a rotating speed sensor, and the rotating speed sensor is used for detecting the self-rotation speed of the pipe.

[0087] The control management unit includes a control system, a pipe detection module, a wall thickness adjustment module, and a quality detection module. The ultrasonic probe 22, the rotating speed sensor, the pipe detection module, the wall thickness adjustment module, and the quality detection module are controlled by the control system.

[0088] The pipe detection module measures the outer diameter, the inner diameter, and the wall thickness of the pipe by the ultrasonic detection probe, calculates the wall thickness deviation, detects the material performance parameters, and analyzes and processes the data.

[0089] In embodiment two, the rotating speed sensor on the support plate 7 can detect the self-rotation speed of the pipe in real time and feed back the data to the control system, so as to ensure that the rotation speed of the pipe is stable within the set range and avoid that the fluctuation of the rotation speed affects the cutting precision. If the rotation speed is abnormal, the control system can timely adjust the output of the first motor 6 to ensure the machining stability.

[0090] The control management unit integrates multi-module functions, and the control system as the core coordinates the work of each component. The pipeline detection module obtains the outer diameter, inner diameter, wall thickness and other parameters of the pipeline through the ultrasonic probe 22, performs multi-point measurement to ensure comprehensive data, calculates the wall thickness deviation, detects the material performance, and analyzes and processes the data to provide accurate basis for cutting. The wall thickness adjustment module controls the action of the cutting assembly according to the detection data, and accurately adjusts the cutting amount. The quality detection module performs secondary detection on the cut pipeline to ensure that the wall thickness is uniform and up to standard. The modules work together to make the entire processing process intelligent and accurate, greatly improving the quality and efficiency of the wall thickness processing of large-diameter seamless stainless steel pipes.

[0091] The control system in the above technical solution can be selected from the Siemens S7-1200 series PLC, such as the S7-1214CDC / DC / DC model.

[0092] It can receive detection signals such as ultrasonic probe 22 and speed sensor through digital and analog modules, process and output control instructions to servo motors, cylinders and other execution components. This model supports multiple communication protocols, facilitates data interaction with each module, and has rich programming software functions, which can realize complex control logic, meet the high-precision control requirements of the device for pipeline wall thickness detection and cutting adjustment, and adapt to the operation requirements of the device automation and intelligence.

[0093] Among them, the distribution of measurement points should uniformly cover the entire length and circumferential direction of the pipeline. For a long pipeline, measurement sections can be set at certain intervals (such as every 100 mm), and at least 8 measurement points are set for each section.

[0094] Let the nominal outer diameter of the pipeline be D0, the nominal inner diameter be d0, and the nominal wall thickness be t0, where t0 = (D0 - d0) / 2;

[0095] In the measurement, the outer diameter of each measurement point of the pipeline is D i , i = 1, 2, …, n, n is the total number of measurement points, the inner diameter is d i , and the actual wall thickness of each point is t i = (D i -d i ) / 2;

[0096] Calculate the wall thickness deviation:

[0097] According to the actual wall thickness t i obtained by measurement, the wall thickness deviation of each point is calculated, and the wall thickness deviation Δt i is defined as the difference between the actual wall thickness and the nominal wall thickness, that is:

[0098] Δt i = t i -t0;

[0099] At the same time, the maximum wall thickness deviation Δt max and the minimum wall thickness deviation Δt min , that is:

[0100] Δt max = max(Δt i );

[0101] Δt min = min(Δt i );

[0102] In order to more intuitively reflect the uneven degree of wall thickness, the wall thickness deviation rate η i is calculated, and the formula is:

[0103] η i = (Δt i / t0) × 100%;

[0104] Material performance parameter detection:

[0105] The mechanical property parameters of the pipe material are detected by tensile test, hardness test and other methods, including yield strength σ s , tensile strength σ b , elastic modulus E, Poisson's ratio μ, etc.; these parameters will be used for mechanical analysis and calculation in the subsequent wall thickness adjustment process.

[0106] Data analysis and processing:

[0107] The measured geometric parameters and material performance parameters are sorted and analyzed, the wall thickness distribution curve and the wall thickness deviation curve are drawn, and the uneven area and degree of the pipe wall thickness are determined. According to the analysis results, it is judged whether the pipe needs to be processed to have equal wall thickness and the key area of processing is determined. If the absolute value of the maximum wall thickness deviation rate exceeds the preset allowable range (such as 5%), the pipe needs to be processed to have equal wall thickness.

[0108] The technical solutions are explained as follows: the comprehensive pipeline parameter detection and analysis lay a precise data foundation for subsequent equal wall thickness processing, and have a significant early guarantee effect. In this step, high-precision measuring instruments are used to detect the pipeline geometric parameters at multiple points, covering the full length and circumferential direction of the pipeline, so as to ensure that the obtained data are comprehensive and representative. Through calculation of wall thickness deviation and deviation rate and the like, the uneven areas and degree of pipeline wall thickness can be intuitively reflected, and the blindness caused by insufficient data in traditional processing is avoided. The detection of material mechanical property parameters provides a key basis for subsequent mechanical analysis and process design, and ensures that the core mechanical properties of the pipeline are not affected in the processing process. In the data analysis link, the wall thickness distribution curve is drawn to clearly locate the problem area, so that the subsequent processing is more targeted. When the maximum wall thickness deviation rate exceeds the preset range, the processing flow is started, which effectively avoids the problems of excessive processing or insufficient processing, ensures the product quality, reduces unnecessary cost consumption, and lays a solid foundation for the scientificity and effectiveness of the entire processing scheme.

[0109] The wall thickness adjustment module includes wall thickness adjustment amount calculation and processing process parameter selection;

[0110] Wall thickness adjustment amount calculation:

[0111] For the area with relatively thick wall thickness, the excess wall thickness needs to be removed by cutting;

[0112] Let the target wall thickness be t target , which is usually the nominal wall thickness t0 or determined according to actual use requirements, and the theoretical removal amount δ i理论 for the area where the wall thickness needs to be removed;

[0113] δ i理论 = t-t target ;

[0114]

[0115] In the actual wall thickness processing process, due to the elastic deformation of the pipeline itself and various factors in the processing process, the actual removal amount may deviate from the theoretically calculated removal amount. In order to improve the accuracy of wall thickness processing,

[0116] A wall thickness correction coefficient calculation formula is designed: where λ i is the wall thickness correction coefficient of the i th measurement point; k1 is a wall thickness deviation influence coefficient, which is obtained by experimental data fitting, and the value range is 0.01-0.05; k2 is a cutting speed and elastic modulus influence coefficient, and the value range is 10 -6 -5×10 -6 ; the dimension of k2 is the reciprocal of the dimension of λ , that is, the dimension of k2 is: M·L -2 ·T-1 , k3 is the feed rate and the actual wall thickness influence coefficient, the value range is 0.1-0.5; Δt i is the wall thickness deviation of the i-th measuring point; v is the cutting speed, the dimension is: L·T -1 ; E is the elastic modulus, the dimension is: M·L -1 ·T -2 ; f is the feed rate; t i is the actual wall thickness of the i-th measuring point;

[0117] The function is to calculate the corresponding wall thickness correction coefficient according to the wall thickness deviation of different measuring points, cutting speed, material elastic modulus, feed rate and actual wall thickness, which is used to correct the theoretical removal amount,

[0118] The actual removal amount δ i after correction is:

[0119] δ i = δ i理论 × λ i ;

[0120] So that the actual removal amount is closer to the target value, thereby improving the accuracy of the wall thickness treatment. When calculating the removal amount, the mechanical performance requirements of the pipeline need to be considered. According to the strength theory in material mechanics, the wall thickness of the pipeline under internal pressure should meet the strength condition. For thin-walled pipelines under internal pressure, the wall thickness calculation formula is:

[0121]

[0122] Where t is the calculated wall thickness, p is the design internal pressure, D is the internal diameter of the pipeline, σ allow is the allowable stress of the material, and when determining the target wall thickness t target , it is ensured that it meets the above strength condition, that is, t target ≥ t;

[0123] Process parameter selection:

[0124] The determined process parameters include cutting speed v, feed rate f, cutting depth a p , and the calculation formula of cutting speed v is:

[0125]

[0126] Where D is the diameter of the pipeline during turning, n is the speed of the pipeline, the feed rate f is the distance that the cutting tool moves along the feed direction per revolution of the pipeline, and the cutting depth a p is the depth of the cutting tool into the pipeline. In the wall thickness treatment, a p is equal to or less than the wall thickness removal amount δ i ;

[0127] The magnitude of cutting force directly affects the stability of the machining process and the quality of the pipe machining. In order to more accurately control the cutting process, a cutting force prediction formula is designed:

[0128]

[0129] where F c is the main cutting force, with the dimension of M·L·T -2 ; C F is the cutting force coefficient, related to the tool material and workpiece material, and for stainless steel material and carbide tool, the value range is 500-800; x F is the cutting depth index, with the value range of 0.8-1.0; y F is the feed rate index, with the value range of 0.6-0.8; n F is the cutting speed index, with the value of 0; m F is the tensile strength index, with the value of 1; p F is the wall thickness correction coefficient index, with the value range of 0.2-0.4; a p is the cutting depth; f is the feed rate; v is the cutting speed; σ b is the tensile strength of the pipe; λ i is the wall thickness correction coefficient of the i-th measurement point.

[0130] Through this formula, the cutting force under different process parameter combinations can be predicted, so as to select appropriate process parameters, avoid pipe deformation or tool damage due to excessive cutting force, and at the same time ensure machining efficiency and quality. According to the cutting performance of stainless steel material, the recommended cutting speed is 80-150 m / min, the feed rate is 0.1-0.3 mm / r, and the cutting depth is reasonably selected according to the removal amount, but it should not be too large, otherwise it will cause large cutting force and cutting heat, affecting the performance of the pipe.

[0131] In order to verify the feasibility and reasonableness of the wall thickness adjustment scheme, finite element analysis software (such as ANSYS, ABAQUS, etc.) is used to simulate and analyze the processing process, a three-dimensional finite element model of the pipe is established, material properties, boundary conditions and load parameters are set, and stress and strain distribution, temperature field change of the pipe under different processing parameters are simulated. Through finite element simulation, possible problems in the processing process can be predicted, such as excessive residual stress, surface damage, etc., and the processing scheme can be optimized and adjusted according to the simulation results. For example, by adjusting the cutting parameters, the cutting force and cutting heat are reduced, and the generation of residual stress is reduced.

[0132] The above technical solution is explained as follows: By combining theoretical removal amount calculation with an innovative wall thickness correction coefficient formula, the shortcomings of traditional calculations that do not consider elastic deformation and processing factors are effectively compensated for, making the actual removal amount closer to the target value and significantly improving the wall thickness processing accuracy. The introduction of a cutting force prediction formula allows for advance prediction of the cutting force under different combinations of process parameters, providing a quantitative basis for process parameter selection and avoiding pipe deformation or tool damage due to excessive cutting force. The target wall thickness is determined based on the theory of material mechanics strength, ensuring that the processed pipe meets the internal pressure requirements and guaranteeing safety in use. The application of finite element simulation analysis can predict potential residual stress, surface damage, and other problems that may occur during the processing, reducing risks by optimizing parameters and decreasing trial-and-error costs in actual processing. This step combines theoretical calculation, innovative formulas, and simulation analysis, making the solution both accurate and feasible, providing reliable guidance for subsequent processing implementation.

[0133] The quality inspection module performs quality inspection on the pipes that have undergone wall thickness treatment, including wall thickness accuracy testing.

[0134] Wall thickness accuracy inspection:

[0135] The thickness of the pipe wall after treatment was measured again using an ultrasonic probe.

[0136] Calculate the actual wall thickness t′ at each measurement point. i With target wall thickness t target Deviation;

[0137] Where, Δt′ i =t′ i -t target ;

[0138] And calculate the maximum deviation Δt′ max and minimum deviation Δt′ min and deviation rate η′ i ;

[0139] η′ i =(Δt′) i / t target )×100%;

[0140] The absolute value of the wall thickness deviation rate after processing must not exceed the preset allowable range (e.g., 3%); otherwise, secondary processing is required.

[0141] It also includes surface quality inspection.

[0142] The surface quality of the pipeline is detected by visual inspection, surface roughness instrument and the like. The visual inspection mainly observes whether there are cracks, scratches, depressions, pores and the like on the surface of the pipeline; the surface roughness instrument is used to measure the roughness parameter Ra of the surface of the pipeline, and the value of Ra is required to be not greater than the design requirement (such as 1.6 μm). For slight defects on the surface, polishing and the like can be used for repair; for serious defects, the causes are analyzed and corresponding remedial measures are taken, and if necessary, the pipeline is scrapped.

[0143] The mechanical property detection also includes:

[0144] The sample is cut on the treated pipeline, and the tensile test, hardness test and the like are carried out to detect whether the mechanical property of the pipeline changes. The detection result is compared with the mechanical property parameter before the treatment to evaluate the influence of the treatment process on the mechanical property of the pipeline. The mechanical property indexes such as yield strength and tensile strength of the treated pipeline are required to be not less than 90% of those before the treatment, and meet the relevant standards and design requirements. If the mechanical property decreases too much, the causes are analyzed, such as whether the material is overheated and softened due to cutting heat and the like, and corresponding improvement measures are taken.

[0145] The nondestructive testing also includes:

[0146] The nondestructive testing methods such as ultrasonic flaw detection and ray flaw detection are used to detect the defects inside and on the surface of the pipeline. The ultrasonic flaw detection can detect the internal cracks, interlayer, incomplete penetration and the like of the pipeline; the ray flaw detection can detect the volume defects such as pores and slag inclusion inside the pipeline. The nondestructive testing result is required to meet the requirements of the relevant standards, and defects affecting the safe use of the pipeline are not allowed. If defects are found, the position, size and nature of the defects are determined, and corresponding treatment measures are taken.

[0147] The above technical solutions are explained as follows: by using the same measurement method as in the previous stage, the wall thickness deviation before and after the treatment is compared, the treatment effect can be accurately evaluated, the wall thickness deviation rate after the treatment is controlled in the preset range, and the high-precision engineering requirement is met. The surface quality detection discovers the surface cracks, scratches and the like defects in time through visual inspection and roughness measurement, and guarantees the appearance and use performance of the pipeline through repair or scrapping treatment. The mechanical property detection ensures that the treatment process does not significantly affect the mechanical property of the pipeline by comparing the yield strength, tensile strength and the like indexes before and after the treatment, and guarantees the structural safety of the pipeline. The nondestructive testing technology can deeply detect the internal defects of the pipeline, and avoids the safety hidden danger caused by hidden defects. The step forms a multi-dimensional quality verification system, and through strict detection standards and standardized detection process, unqualified products flowing into the market is effectively prevented, and the final guarantee for the safe use of the pipeline is provided.

[0148] In the description of the application, it is necessary to point out that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "linking" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium, can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0149] Although embodiments of the application have been shown and described, the scope of the application is defined by the appended claims and their equivalents.

Claims

1. An apparatus for equalizing wall thickness of a large-diameter seamless stainless steel pipe, characterized by comprising: The utility model relates to a kind of steel pipe cutting device, including: Base (1), support plate (7) is fixedly connected on the base (1), the support plate (7) is V-shaped structure, the outside rotationally connected of support plate (7) has multiple groups of ball (8); Stand (2), the stand (2) is fixedly connected on base (1), drive assembly is equipped on the stand (2), the drive assembly is used to drive the rotation of pipeline on support plate (7), rotation speed sensor is also fixedly installed on support plate (7); Cutting assembly, the cutting assembly is arranged on base (1), for cutting steel pipe; Control management unit, the control management unit controls cutting assembly, also detects the diameter and wall thickness of pipeline, completes wall thickness deviation calculation; The control management unit includes control system, pipeline detection module, wall thickness adjustment module, quality detection module, rotation speed sensor, pipeline detection module, wall thickness adjustment module, quality detection module are controlled by control system; Wall thickness adjustment module includes wall thickness adjustment amount calculation and process parameter selection; Wall thickness adjustment amount calculation: For the area of thicker wall thickness, need to remove excess wall thickness by cutting; Let the target wall thickness be t target , for the area that needs to remove the wall thickness, its theoretical removal amount δ i理论 ; delta i理论 = t i - t target ; wherein, λ i is the wall thickness correction coefficient of the i-th measuring point; k1 is the wall thickness deviation influence coefficient, with a value range of 0.01-0.05; k2 is the cutting speed and elastic modulus influence coefficient, with a value range of 10 -6 -5×10 -6 ; the dimension of k2 and the dimension of are reciprocal, that is, the dimension of k2 is M·L ; the dimension of k2 is M·L -2 ·T -1 ; k3 is the feed amount and actual wall thickness influence coefficient, with a value range of 0.1-0.5; Δt i is the wall thickness deviation of the i-th measuring point; v is the cutting speed; the dimension is L·T -1 ; E is the elastic modulus, with a dimension of: M·L -1 ·T -2 ; f is the feed amount; t i is the actual wall thickness of the i-th measuring point; Corrected actual removal δ i is: δ i = δ i理论 x λ i ; For thin-walled pipeline that bears internal pressure, its wall thickness calculation formula is: Where t is the calculated wall thickness, p is the design internal pressure, D is the pipe inner diameter, and σ allow Given the allowable stress of the material, and the target wall thickness t is determined... target At that time, ensure that it meets the strength condition, i.e., t target ≥t; Process parameter selection: The determined process parameters include a cutting speed v, a feed amount f, and a cutting depth a p A calculation formula of the cutting speed v is wherein D is the diameter of the pipe at the time of turning, n is the rotational speed of the pipe, the feed amount f is the distance that the cutting tool moves in the feed direction per one revolution of the pipe, and the cutting depth a p is the depth at which the cutting tool cuts into the pipe, and in the wall thickness processing, a p is equal to or less than the wall thickness removal amount δ i ; Design cutting force prediction formula: wherein F c is the main cutting force dimensioned as M·L·T -2 ; C F is the cutting force coefficient, which is related to the tool material and the workpiece material, and for stainless steel material and a carbide tool has a value range of 500-800; x F is the cutting depth index, which has a value range of 0.8-1.0; y F is the feed rate index, which has a value range of 0.6-0.8; n F is the cutting speed index, which has a value of 0; m F is the tensile strength index, which has a value of 1; p F is the wall thickness correction coefficient index, which has a value range of 0.2-0.4; a p is the cutting depth; f is the feed rate; v is the cutting speed; σ b is the tensile strength of the pipe; λ i is the wall thickness correction coefficient of the i-th measuring point; and x F +y F = 2. Finite element analysis software is used to simulate analysis on treatment process, to establish the three-dimensional finite element model of pipeline, to set material attribute, boundary condition and load parameter, to simulate the stress and strain distribution of pipeline under different treatment process parameters, temperature field changes.

2. The apparatus for equalizing wall thickness of a large-diameter seamless stainless steel pipe according to claim 1, characterized by The drive assembly includes first motor (6) and friction wheel (5), the friction wheel (5) is equipped with two groups, rotationally connected on the both sides of mounting seat (4) respectively, the first motor (6) is fixedly connected on the outside of mounting seat (4), the output end of first motor (6) is fixedly connected with friction wheel (5), the stand (2) is fixedly connected with first air cylinder (3), the output end of first air cylinder (3) is fixedly connected with mounting seat (4).

3. The apparatus for equalizing wall thickness of a large-diameter seamless stainless steel pipe according to claim 2, characterized by Second air cylinder (10) is fixedly connected on the base (1), the output end of second air cylinder (10) is fixedly connected with lifting plate (11), the top of lifting plate (11) is fixedly connected with second motor (12) on both sides, the output end of second motor (12) is fixedly connected with first threaded rod (13), the outside of first threaded rod (13) is threadedly connected with first nut block (15), the top of lifting plate (11) is fixedly connected with first limiting rod (14), first limiting rod (14) penetrates first nut block (15), the top of first nut block (15) is rotationally connected with rotating roller (16), the bottom of support plate (7) is equipped with first sliding port (9), rotating roller (16) passes through first sliding port (9).

4. The apparatus for equalizing wall thickness of a large-diameter seamless stainless steel pipe according to claim 3, characterized by The outer part of the stand (2) is fixedly connected with a side frame (20), the outer part of the side frame (20) is fixedly connected with a third motor (17), the output end of the third motor (17) is fixedly connected with a second threaded rod (18), the outer part of the second threaded rod (18) is threadedly connected with a second nut block (19), the outer part of the side frame (20) is provided with a second sliding opening (21), the second nut block (19) is slidingly connected in the second sliding opening (21), and the outer part of the second nut block (19) is fixedly connected with an ultrasonic probe (22).

5. The apparatus for equalizing wall thickness of a large-diameter seamless stainless steel pipe according to claim 4, characterized by The cutting assembly comprises a moving frame (28) and a cutting tool (29) fixedly connected to the outer part of the moving frame (28), the base (1) is fixedly connected with a fixed frame (23), the outer part of the fixed frame (23) is fixedly connected with a servo motor, the output end of the servo motor is fixedly connected with a third threaded rod (24), the outer part of the third threaded rod (24) is threadedly connected with a third nut block (26), the outer part of the fixed frame (23) is fixedly connected with a second limiting rod (25), the second limiting rod (25) penetrates through the third nut block (26), and the outer part of the third nut block (26) is fixedly connected with an electric push rod (27), and the output end of the electric push rod (27) is fixedly connected with the moving frame (28).

6. The apparatus for equalizing wall thickness of a large-diameter seamless stainless steel pipe according to claim 5, characterized by The pipeline detection module measures the outer diameter, inner diameter and wall thickness of the pipeline by the ultrasonic detection probe, and simultaneously performs wall thickness deviation calculation, material performance parameter detection and data analysis and processing; The distribution of the measuring points should uniformly cover the entire length and circumferential direction of the pipeline; Supposing that the nominal outer diameter of the pipeline is D0, the nominal inner diameter is d0, and the nominal wall thickness is t0, wherein t0=(D0-d0) / 2; In the measurement, the outer diameter of each measuring point of the pipeline is D i , i = 1, 2, …, n, n is the total number of measuring points, the inner diameter is d i , the actual wall thickness of each point is t i = (D i -d i ) / 2; The wall thickness deviation calculation is performed: The actual wall thickness t is measured i The wall thickness deviation Δt i at each point is calculated as the difference between the actual wall thickness and the nominal wall thickness, i.e. Δt i = t i - t0; At the same time, the maximum wall thickness deviation At is calculated max and the minimum wall thickness deviation At min i.e.: Δt max = max(Δt i ); Δt min = min(Δt i ); The wall thickness deviation rate η is calculated i The formula is: η i = (At i / t0) x 100%; The material performance parameter detection is performed: The mechanical property parameters of the pipe material are detected, including yield strength σ s , tensile strength σ b , elastic modulus E, and Poisson's ratio μ; The data analysis and processing are performed: The measured geometric parameters and material performance parameters are sorted and analyzed, the wall thickness distribution curve and the wall thickness deviation curve are drawn, the uneven wall thickness area and degree of the pipeline are determined, according to the analysis result, whether the pipeline needs to be processed to have uniform wall thickness and the key area of the processing is determined, and if the absolute value of the maximum wall thickness deviation rate exceeds the preset allowable range, the pipeline needs to be processed to have uniform wall thickness.

7. The apparatus for equalizing wall thickness of a large-diameter seamless stainless steel pipe according to claim 6, characterized by The quality detection module detects the quality of the pipeline processed to have uniform wall thickness, and the wall thickness precision detection is performed; The wall thickness precision detection is performed: The ultrasonic probe is used to measure the wall thickness of the processed pipeline again; calculating the actual wall thickness t' of each measurement point i deviation from the target wall thickness t target ; where Δt' = t' - t i = t' - t i = t' - t target ; and the maximum deviation Δt' max and the minimum deviation Δt' min and the deviation rate η' i ; η' i = (Δt' i / t target ) x 100%; The absolute value of the wall thickness deviation rate of the processed pipeline does not exceed the preset allowable range, otherwise, the pipeline needs to be processed again.

Images