Method for optimizing process parameters of stainless steel pipe joint cone rolling strengthening and application

Abstract

This invention discloses a method and application for optimizing the process parameters of the tumbling and strengthening process for conical surfaces of stainless steel pipe joints. The method includes: acquiring key process parameters affecting the surface condition of the tumbling and strengthening process; performing tumbling and strengthening on a batch of conical surfaces of stainless steel pipe joints using a set of tumbling and strengthening process parameters; optimizing the tumbling and strengthening process parameters according to a set fluctuation coefficient; performing tumbling and strengthening on another batch of conical surfaces of stainless steel pipe joints using the optimized tumbling and strengthening process parameters; and detecting the surface condition and performance after tumbling and strengthening. This process is repeated iteratively, using the fluctuation coefficient to optimize the tumbling and strengthening process parameters. The optimal process parameters are determined by analyzing the correlation between surface yellowing and the tumbling and strengthening process parameters and surface performance data. An iterative cyclic analysis method combining key process parameters and surface condition / performance detection is used to iteratively optimize the tumbling and strengthening process parameters, thereby achieving optimization of the tumbling and strengthening process parameters.

Description

Technical Field

[0001] This invention belongs to the field of machining technology, specifically relating to a method and application for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints. Background Technology

[0002] Stainless steel, a metallic material possessing high strength, high plasticity, and excellent corrosion resistance, is commonly used in connectors for various piping systems. Austenitic stainless steel is characterized by high toughness and low thermal conductivity, leading to challenges in its processing, such as large plastic deformation during cutting, severe work hardening, and high cutting heat. This necessitates stringent control of processing parameters.

[0003] Burnishing is a process for strengthening pipe fittings by effectively reducing surface roughness and improving the sealing performance of pipe connections. Burnishing uses high-hardness, smooth rollers in direct contact with the conical surface of the pipe fitting, causing localized micro-plastic deformation on the machined surface. This reduces the height difference between surface protrusions and depressions, achieving ultra-precision machining with reduced surface roughness. Due to contact pressure and friction, heat is inevitably generated during the process. The passive oxide film formed on the surface of stainless steel plays a crucial protective role in improving the alloy's corrosion resistance. High-temperature environments alter the structure and thickness of the oxide film on the stainless steel surface, leading to changes in its density and affecting the material's corrosion resistance.

[0004] Currently, the burnishing strengthening process mainly adopts a combination of ball-bearing burnishing cutters and CNC equipment, focusing on the processing efficiency, cost, and surface strengthening effect of the parts. In the burnishing strengthening process of the conical surface of stainless steel pipe joints, the product will have the problem of yellowing and discoloration of the conical surface of the pipe joint, which affects the surface quality of the product. Summary of the Invention

[0005] The purpose of this invention is to provide a method and application for optimizing the process parameters of the burnishing and strengthening process of the conical surface of stainless steel pipe joints, so as to solve the problem of yellowing and discoloration of the conical surface of pipe joints.

[0006] This invention is achieved through the following technical solution:

[0007] Methods for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints include:

[0008] Obtain the key process parameters that affect the surface condition of the burnishing and strengthening process;

[0009] A set of tumble-hardening process parameters were used to tumble-harden the conical surfaces of a batch of stainless steel pipe joints, and the surface condition and performance after tumble-hardening were tested.

[0010] The tumbling and strengthening process parameters are optimized according to the set fluctuation coefficient. The optimized tumbling and strengthening process parameters are then used to tumble and strengthen the conical surfaces of another batch of stainless steel pipe joints. The surface condition and performance after tumbling and strengthening are then tested. This process is repeated, and the tumbling and strengthening process parameters are iteratively optimized using the fluctuation coefficient until a yellowing problem is found in the surface condition test.

[0011] By comparing the performance test data of different batches of tumble-hardened surfaces, the optimal process parameters were determined by analyzing the correlation between surface yellowing and tumble-hardening process parameters and surface performance data.

[0012] In some embodiments of the present invention, the correlation between surface yellowing and the tumbling strengthening process parameters and surface performance data is that the tumbling strengthening process parameters used are positively correlated with the cutting heat generated during processing and the surface performance data, and negatively correlated with the probability of surface yellowing.

[0013] In some embodiments of the present invention, among the various sets of tumbling strengthening process parameters that are iteratively optimized, the previous set of tumbling strengthening process parameters corresponding to the occurrence of surface yellowing problem is taken as the optimal process parameters.

[0014] In some embodiments of the present invention, key process parameters affecting the surface condition of the burnishing process are obtained based on the force model of the tapered surface hardening process of the pipe joint and the calculation formula of the cutting heat generated during the processing.

[0015] In some embodiments of the present invention, the key process parameters obtained include cutting speed, feed rate, depth of feed, and rolling pressure.

[0016] In some embodiments of the present invention, the cutting speed, feed rate, and feed depth are set machining equipment input parameters, and the rolling pressure is obtained by measurement.

[0017] In some embodiments of the present invention, the fluctuation coefficient is determined based on the accuracy of the processing equipment and the testing equipment.

[0018] In some embodiments of the present invention, the detection of the surface condition after tumble burnishing includes the detection of surface appearance color, surface roughness, and surface damage.

[0019] In some embodiments of the present invention, the testing of the surface properties after tumble finishing includes testing the depth of the surface work-hardened layer, the surface oxygen content, and the hardness of the surface work-hardened layer and the substrate area.

[0020] On the other hand, the present invention also provides an application of the method for optimizing the process parameters of the stainless steel pipe joint conical surface burnishing strengthening process, wherein the obtained optimal process parameters are used to perform burnishing strengthening processing on the conical surface of the stainless steel pipe joint.

[0021] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0022] This invention analyzes the mechanism that causes yellowing on the burnished surface of stainless steel pipe joints, extracts the key process parameters that cause the problem, and uses an iterative cyclic analysis method that combines key process parameters with surface condition / performance testing to iteratively optimize the burnishing process parameters. This optimization of the burnishing process parameters effectively solves the problem of yellowing on the burnished surface of stainless steel pipe joints.

[0023] This invention is based on an iterative optimization path of "quality inspection - failure analysis - parameter optimization", which realizes a closed loop of "problem mechanism - optimization - verification" and ensures the stability of the optimization effect.

[0024] This invention comprehensively considers the impact of cutting heat on the quality of stainless steel pipe joint parts. While eliminating the impact of the burnishing process on the surface quality of the pipe joint, it can also take into account the surface strengthening effect such as surface roughness, and can well guarantee the surface processing quality of burnishing. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a logic diagram of the method for optimizing the process parameters of the tapered surface burnishing strengthening of stainless steel pipe joints according to an embodiment of the present invention.

[0027] Figure 2 This is a flowchart illustrating the optimization method for the tapered surface burnishing strengthening process parameters of stainless steel pipe joints according to an embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0029] This invention employs an iterative cyclical analysis method of "part surface condition - surface properties - tumbling strengthening process parameters - part surface condition". By analyzing the mechanism of yellowing of the conical surface, the tumbling strengthening process parameters are iteratively optimized to obtain a combination of process parameters that ensures the stability of the part condition, thereby solving the problem of yellowing of the surface of stainless steel pipe joints after tumbling strengthening of the conical surface.

[0030] In some embodiments of the present invention, the method for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints is described in reference to... Figure 1 and Figure 2 This includes the following steps:

[0031] 1) Obtaining key process parameters for tumble finishing

[0032] The burnishing process parameters affecting the burnishing performance of the conical surface of stainless steel pipe joints were analyzed, and the key process parameters affecting the burnishing performance of the conical surface of stainless steel pipe joints were determined.

[0033] Analysis revealed that the direct factor affecting the yellowing and discoloration of the conical surface of stainless steel pipe joints during the burnishing process is the cutting heat generated during the burnishing process.

[0034] The interaction in the burnishing strengthening process of pipe fittings is mainly concentrated between the roller cutter and the conical surface of the pipe fitting. Since there is almost no cutting involved in the process, it is suitable for a shear action model. Based on this model, the formula for calculating the cutting heat generated per unit area per unit time on the shear surface during the burnishing strengthening process is as follows:

[0035] ;

[0036] In the formula: F S The shear force is mainly affected by the rolling pressure.

[0037] v S Cutting speed is a process parameter that is directly controllable by the machining equipment.

[0038] A C The contact area is mainly affected by the tool size and the depth of feed.

[0039] The cutting angle is a constant value, determined by the relative position of the roller cutter and the conical surface of the pipe fitting during burnishing.

[0040] According to the above calculation formula, in the process of conical surface burnishing and strengthening of stainless steel pipe joints, cutting speed, feed rate, feed depth and rolling pressure are the key process parameters that affect the generation of cutting heat during the processing, thus causing the surface to turn yellow.

[0041] Among them, cutting speed, feed rate, and depth of feed are parameters that can be directly set in the machining equipment, while rolling pressure is a parameter that can be directly measured during the machining process.

[0042] 2) Setting of burnishing and strengthening process parameters

[0043] Based on the obtained key process parameters, the four basic parameters—cutting speed, feed rate, depth of feed, and rolling pressure—are denoted as follows: v S , v f , H f , F N Establish a four-dimensional vector set that can characterize the effect of cutting heat on burnishing strengthening process. v S , v f , H f , F N ),in, v S , v f , H f These are the initial input parameters for the processing equipment. F N For directly measured parameters.

[0044] For a batch of stainless steel pipe fittings of the same specifications, set a set of initial processing parameters ( v S , v f , H f Using the initial processing parameters, a batch of stainless steel pipe joint tapered surfaces were subjected to burnishing and strengthening, and the corresponding rolling pressure during the burnishing and strengthening process was measured. F N The measured values ​​yielded a set of initial process parameter combinations.

[0045] 3) Surface condition and performance testing of the conical surface of stainless steel pipe joints

[0046] The surface condition of the conical surface of the stainless steel pipe joint is inspected to check whether the key indicators of the burnished and strengthened surface meet the standard requirements, including:

[0047] Use visual inspection or a colorimeter to check whether the color of the parts meets the requirement of being bright and free of discoloration.

[0048] A profilometer is used to check whether the surface roughness of the parts meets the standard requirements.

[0049] Use visual inspection or a magnifying glass to check whether there is any damage on the surface of the parts that exceeds the standard tolerance.

[0050] The surface properties of the conical surface of the stainless steel pipe joint were tested, and the microstructure of the burnished and strengthened surface was characterized, including:

[0051] Metallographic analysis was used to determine the depth of the work-hardened layer on the burnished surface of the pipe joint.

[0052] The oxygen content of the burnished surface of the pipe joint was detected by EDS energy dispersive spectroscopy or XPS.

[0053] The hardness of the work-hardened layer and the substrate area on the burnished and reinforced surface of the pipe joint is tested using a microhardness tester or a nanoindenter.

[0054] 4) Iterative optimization of key process parameters

[0055] Taking into account the precision of processing and testing equipment, and adhering to the principle of controllable small step size fluctuations, the process parameter fluctuation coefficient is set. (Generally, a value of 0.9-1.1 can be used), depending on the set fluctuation parameters. Key process parameters were iteratively optimized.

[0056] When the color, roughness, and surface condition of the tested burnished and strengthened surface all meet the technical requirements, the set fluctuation parameters are used. Iterative optimization of key process parameters, such as fluctuation parameters. maximum value Multiplying by the initial machining parameters yields the iteratively optimized machining parameters, denoted as: .

[0057] The processing parameters were used to perform burnishing and strengthening on the conical surfaces of a batch of stainless steel pipe fittings, and the corresponding rolling pressure was measured during the burnishing and strengthening process. F N The measured values ​​yielded another set of optimized and iteratively combined process parameters, denoted as... , This refers to the measured value of the rolling pressure in this set of process parameters.

[0058] The process is repeated in sequence. When the color, roughness, and surface condition of the tumble-hardened surface meet the technical requirements, the key process parameters are iteratively optimized based on the parameters optimized in the previous iteration with the set fluctuation coefficient, until the color, roughness, and surface condition of the tumble-hardened surface no longer meet the technical requirements.

[0059] For batches of pipe fitting parts exhibiting abnormal yellowing on the surface, failure analysis methods were used to compare the differences between the material hardening layer depth, hardness, oxygen content, and other parameters and qualified materials. The underlying mechanism and process influence of yellowing on the roll-hardened surface of the pipe fittings were analyzed. Through compositional differences and combined with other theoretical studies, the influencing factors causing yellowing on the roll-hardened surface were identified. Based on the analysis results and the roll-hardening process parameters used in each batch, the optimal process parameters were determined.

[0060] Analysis revealed that the depth, hardness, and oxygen content of the yellowed hardened layer on the surface of the tube fittings after tumbling were greater than those of the batches without abnormalities. The cutting speed, feed rate, feed depth, and rolling pressure were all higher in the process parameters used to cause the abnormalities. At this time, the cutting heat generated during the tumbling process was also greater, indicating that the yellowing of the tube fitting surface after tumbling was caused by excessive cutting heat.

[0061] Based on the above analysis, the set of tumbling strengthening process parameters that did not result in localized yellowing of the surface and had the highest parameter values ​​among all batches was selected as the optimal process parameters.

[0062] For example, the combination of process parameters used in the previous round of calendering ( v S0 , v f0 , H f0 , F N0 It can process qualified stainless steel pipe joint conical surfaces, and the next round of burnishing and strengthening process parameter combination will be used. , The measured value of the rolling pressure in this set of burnishing and strengthening process parameters indicates that the surface of the conical surface of the processed stainless steel pipe joint is yellowing. Therefore, the previous set of process parameters ( v S0 , v f0 , H f0 , F N0 The optimal process parameters for laser strengthening of stainless steel pipe joints of this specification can both avoid the influence of cutting heat on the surface condition and ensure the processing effect of the burnishing strengthened surface.

[0063] The process of the method of the present invention will be described in detail below with reference to specific embodiments.

[0064] (1) Setting of process parameters for tumbling strengthening

[0065] Regarding D N For a 12mm 1Cr18Ni9Ti stainless steel pipe fitting, the process parameters affecting the cutting heat generated during the burnishing and strengthening process of this pipe fitting are cutting speed, feed rate, and depth of feed. Based on production experience, ( v S , v f , H fThe initial input values ​​are set to (400 r / min, 0.01 mm / r, 0.03 mm). A force gauge is used to measure the rolling force during the burnishing process. F N The measured value was 826 N, and the initial process parameter combination was obtained as (400 r / min, 0.01 mm / r, 0.03 mm, 800 N).

[0066] (2) First round of surface condition inspection

[0067] The stainless steel pipe joint tapered surface processed according to the initial process parameters is bright and colorless, with an average surface roughness of Ra0.5. No obvious damage was observed on the processed surface, which meets the requirements for the processed surface condition.

[0068] (3) First round of surface performance testing

[0069] Material characterization analysis was conducted on the processed surface of stainless steel pipe joints. Metallographic analysis was used to obtain a work-hardened layer depth of approximately 20 μm. EDS energy dispersive spectroscopy was used to measure the oxygen content of the burnished surface of the pipe joint, which was approximately 0.8%. Microhardness testers were used to measure the hardness of the work-hardened layer and the substrate region of the burnished surface of the pipe joint, which were approximately 216 HV0.1 and 194 HV0.1, respectively.

[0070] (4) First round of process parameter iterative optimization

[0071] Based on the precision of the processing and testing equipment, and adhering to the principle of controllable small step size fluctuations, the process parameter fluctuation coefficient is set. It is 1.1.

[0072] according to Figure 2 The process parameters were optimized and iterated throughout the process. In the first round of part machining, the surface color, roughness, and surface condition all met the technical requirements, with the fluctuation coefficient... =1.1 multiplied by the processing parameters of the first round to obtain the processing parameters for the new round of burnishing and strengthening, and then proceed with the processing of the next batch of parts. That is, the equipment input parameters for the second round of burnishing are set to (440r / min, 0.011mm / r, 0.033mm). In the second round of processing, a force gauge is used to measure the rolling pressure. F N The measured value is 898N, which means that the combination of parameters for the second round of tumbling strengthening process is (440r / min, 0.011mm / r, 0.033mm, 898N).

[0073] (5) Second round of surface condition inspection

[0074] The stainless steel pipe joint parts processed according to the initial process parameters have a bright and colorless surface with an average surface roughness of Ra0.3. No obvious damage was observed on the processed surface, which meets the requirements for the processed surface condition.

[0075] (6) Second round of surface performance testing

[0076] Material characterization analysis was conducted on the processed surface of stainless steel pipe joints. Metallographic analysis was used to obtain a work-hardened layer depth of approximately 33 μm. EDS energy dispersive spectroscopy was used to measure the oxygen content of the burnished surface of the pipe joint, which was approximately 1.1%. The hardness of the work-hardened layer and the substrate area of ​​the burnished surface of the pipe joint were measured to be approximately 236 HV0.1 and 195 HV0.1, respectively, using a microhardness tester.

[0077] (7) Second round of process parameter iterative optimization

[0078] according to Figure 2 The process parameters were optimized and iterated throughout the process. After the second round of part machining, the surface color, roughness, and surface condition all met the technical requirements. A third round of material characterization was then conducted, using the fluctuation coefficient as a metric. =1.1 multiplied by the processing parameters of the second round is used as the processing parameters for the new round of burnishing and strengthening processing, and the next batch of parts is processed. That is, the equipment input parameters for the third round of burnishing process are set as (484r / min, 0.012mm / r, 0.036mm). The rolling pressure is measured using a force gauge in the third round of processing. F N The measured value is 959N, which means that the combination of parameters for the third round of tumbling strengthening process is (484r / min, 0.012mm / r, 0.036mm, 959N).

[0079] (8) Third round of surface condition inspection

[0080] The stainless steel pipe joint parts processed according to the initial process parameters showed localized yellowing on the surface, with an average surface roughness of Ra0.2, and no obvious damage was observed on the processed surface.

[0081] The surface condition of the part does not meet the requirement of a bright and colorless surface.

[0082] (9) Third round of surface performance testing

[0083] Material characterization analysis was conducted on the processed surface of stainless steel pipe joints. Metallographic analysis was used to obtain a work-hardened layer depth of approximately 86 μm. EDS energy dispersive spectroscopy was used to measure the oxygen content of the conical surface of the pipe joint, which was approximately 2.3%. The hardness of the work-hardened layer and the substrate area of ​​the tube joint were measured to be approximately 246 HV0.1 and 195 HV0.1, respectively, using a microhardness tester.

[0084] For the batch of pipe fitting parts exhibiting abnormal yellowing on the surface, failure analysis was used to compare the differences in parameters such as the depth of the hardened layer, hardness, and oxygen content with those of qualified materials. This showed that the yellowed stainless steel pipe fittings with conical surfaces after tumble finishing had a deeper hardened layer, greater hardness, and higher oxygen content. Furthermore, the corresponding process parameters used were higher in terms of cutting speed, feed rate, depth of feed, and rolling pressure, further proving that the yellowing was caused by excessive cutting heat during the tumble finishing process. Compared to the next step of process parameter iteration and optimization, the second round of tumble finishing achieved optimal results while maintaining the integrity of the part's surface condition.

[0085] (10) Determine the optimized process parameters

[0086] Reference Figure 2 The output of stable and optimized process parameters is the second round of process parameters (440r / min, 0.011mm / r, 0.033mm, 898N). Using this set of process parameters, the conical surface of the stainless steel pipe joints of this batch of specifications is subjected to burnishing and strengthening processing.

[0087] According to the inspection of the surface condition of the processed parts, the surface condition of the processed parts is stable, there is no yellowing problem, and the surface properties can meet the requirements of the tumbling and strengthening process.

[0088] On the other hand, in some embodiments of the present invention, an optimization method for the process parameters of the tapered surface of a stainless steel pipe joint is applied, which uses the optimal process parameters obtained in the above embodiments to perform tapered surface strengthening processing on the stainless steel pipe joint.

[0089] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., used to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of this invention is usually placed in during use. They are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0090] Furthermore, the use of terms such as "horizontal" and "vertical" in the description of this invention does not imply that the components are required to be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0091] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention in light of the specific circumstances.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for optimizing the process parameters of the tapered surface burnishing and strengthening process for stainless steel pipe joints, characterized in that, include: Key process parameters affecting the surface condition of burnishing and strengthening are obtained. Based on the force model of burnishing and strengthening of the conical surface of the pipe joint and the calculation formula of the cutting heat generated during the process, key process parameters affecting the surface condition of burnishing and strengthening are obtained. The key process parameters obtained include cutting speed, feed rate, depth of feed and burnishing force. A set of tumble-hardening process parameters were used to tumble-harden the conical surfaces of a batch of stainless steel pipe joints, and the surface condition and performance after tumble-hardening were tested. The tumbling and strengthening process parameters are optimized according to the set fluctuation coefficient. The optimized tumbling and strengthening process parameters are then used to tumble and strengthen the conical surfaces of another batch of stainless steel pipe joints. The surface condition and performance after tumbling and strengthening are then tested. This process is repeated, and the tumbling and strengthening process parameters are iteratively optimized using the fluctuation coefficient until a yellowing problem is found in the surface condition test. By comparing the performance test data of different batches of tumble-hardened surfaces, the optimal process parameters were determined by analyzing the correlation between surface yellowing and tumble-hardening process parameters and surface performance data.

2. The method for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints according to claim 1, characterized in that, The correlation between surface yellowing and the tumbling strengthening process parameters and surface performance data is that the tumbling strengthening process parameters used are positively correlated with the cutting heat generated during processing and the surface performance data, and negatively correlated with the probability of surface yellowing.

3. The method for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints according to claim 2, characterized in that, Among the various sets of tumbling strengthening process parameters that are iteratively optimized, the set of process parameters preceding the one that corresponds to the yellowing of the surface is taken as the optimal process parameters.

4. The method for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints according to claim 1, characterized in that, The cutting speed, feed rate, and depth of feed are set input parameters for the machining equipment, and the rolling pressure is obtained through measurement.

5. The method for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints according to claim 4, characterized in that, The fluctuation coefficient is determined based on the accuracy of the processing equipment and testing equipment.

6. The method for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints according to claim 1, characterized in that, The inspection of the surface condition after tumble finishing includes the inspection of surface appearance color, surface roughness, and surface damage.

7. The method for optimizing the process parameters of the tapered surface burnishing strengthening process for stainless steel pipe joints according to claim 1 or 2, characterized in that, Testing the surface properties after tumble finishing includes testing the depth of the surface work-hardened layer, the surface oxygen content, and the hardness of the surface work-hardened layer and the substrate area.

8. A method for strengthening the conical surface of stainless steel pipe joints by burnishing, characterized in that, The optimal process parameters are obtained by using the rolling and polishing process parameter optimization method for the conical surface of the stainless steel pipe joint as described in any one of claims 1-7, and the obtained optimal process parameters are used to perform rolling and polishing on the conical surface of the stainless steel pipe joint.

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