A method and apparatus for welding straight seam steel pipes

Abstract

This application relates to the field of welding technology, specifically to a welding method and apparatus for straight seam steel pipes. The method includes: collecting the values ​​of process parameters, joint gap, and joint height at each moment; obtaining preset process parameters and their corresponding standard process parameters; determining a joint defect index based on the difference between the standard process parameters and the process parameters at the current moment, and determining whether correction is needed; determining the general joint gap difference and general joint height difference of a class of defects based on the difference between the joint condition of each defect and the joint condition of a defect-free joint with the same process parameters; determining a possible defect index based on the similarity to the current moment; obtaining a reasonable joint condition based on the possible defect index, and obtaining a corrected welding current and a corrected arc voltage; and performing welding based on the corrected welding current and corrected welding voltage. This application improves the yield rate of straight seam steel pipe welding.

Description

Technical Field

[0001] This application relates to the field of welding technology, specifically to a welding method and welding apparatus for straight seam steel pipes. Background Technology

[0002] High-quality straight seam steel pipes play a crucial role in long-distance liquid transportation systems. However, traditional welding techniques often encounter problems when dealing with thick-walled, large-diameter steel pipes, such as difficulty in controlling the width of the heat-affected zone, decreased mechanical properties of the joints, and severe welding deformation, which seriously affect product quality and production cycle. Therefore, a welding method or device for straight seam steel pipes is needed.

[0003] Because the steel pipe has some angular deviations during JCO forming and some scratches caused by previous processing, laser inspection is difficult to obtain accurate joint information. As a result, the preset process parameters cannot be well matched to the corresponding welding points during subsequent welding. If the voltage and current are unreasonable during welding, defects such as weld beads and burn-through will occur in the steel pipe. Summary of the Invention

[0004] To address the technical problem of welding defects caused by inaccurate seam measurement, this application provides a straight seam steel pipe welding method and welding apparatus, the specific technical solution of which is as follows:

[0005] In a first aspect, this application proposes a method for welding straight seam steel pipes, which includes the following steps:

[0006] Collect the values ​​of process parameters, as well as the weld gap and weld height, at each moment of welding; process parameters include welding current and arc voltage;

[0007] The preset process parameters for the current moment are obtained based on the average of the process parameters for a preset number of time steps prior to the current moment; the standard joint gap and standard joint height corresponding to the preset process parameters are obtained based on historical data; the joint gap difference factor and joint height difference factor are obtained based on the difference between the standard joint gap and standard joint height and the joint gap and joint height at the current moment; the joint defect index for the current moment is determined based on the joint gap difference factor and joint height difference factor, and the process parameters for the current moment are judged based on the joint defect index.

[0008] Based on historical data, different types of defects and their process parameters are obtained. The difference between the joint gap and joint height of each defect and the joint gap and joint height of the same process parameters under defect-free conditions is used to obtain the joint gap defect factor and joint height defect factor for each defect. Based on the joint gap defect factor and joint height defect factor of all defects in the same type, the general joint gap difference and general joint height difference for this type of defect are obtained. For process parameters that need correction, the potential defect index at the current moment is determined based on the similarity between the vectors of the current joint gap difference factor and the joint height difference factor and the vectors of the general joint gap difference and general joint height difference. After weighting the general joint gap difference and general joint height difference based on the potential defect index, the standard joint gap and standard joint height are corrected to obtain the reasonable joint gap and reasonable joint height at the current moment. Based on the process parameters of the reasonable joint gap and reasonable joint height when there are no defects in the historical data, the process parameters at the current moment are corrected to obtain the corrected welding current and corrected arc voltage.

[0009] Welding is performed according to the modified welding current and modified welding voltage.

[0010] In the above scheme, welding process parameters are preset based on the steel pipe condition and previous welding conditions. Then, based on the difference between the current weld joint condition and the previous weld joint condition, it is analyzed whether the preset parameters are applicable to the current weld joint position. If applicable, no adjustment is needed; otherwise, adjustment is required. Next, based on the current weld joint condition and the weld joint and welding parameters when previous welding defects occurred, the defects that may occur when welding with the preset parameters are analyzed. Then, based on the factors that may cause defects, the weld joint condition corresponding to the preset parameters is corrected. Finally, based on the corrected weld joint condition, suitable welding process parameters are constructed. This application can effectively avoid welding defects caused by defects in the pipe blank weld joint due to processing, and can effectively improve the yield rate of straight seam steel pipe welding.

[0011] In one embodiment, the method for obtaining the standard joint gap and standard joint height corresponding to the preset process parameters based on historical data is as follows:

[0012] Obtain the process parameters and their joint gap and joint height from several times prior to the current time; count the process parameters that are the same as the preset process parameters, and calculate the average of the joint gap and joint height of the same process parameters as the standard joint gap and standard joint height.

[0013] In one embodiment, the method for obtaining the joint gap difference factor and joint height difference factor based on the difference between the standard joint gap and standard joint height and the joint gap and joint height at the current moment is as follows:

[0014] Δc w =tanh(cw -c0), Δh w =tanh(h) w -h0), c w c0 represents the current joint gap, and h represents the standard joint gap corresponding to the preset process parameters. w The current joint height is represented by h0, which represents the standard joint height corresponding to the preset process parameters. tanh() represents the hyperbolic tangent function, and Δc... w Δh represents the difference factor in the joint gap at the current moment. w This represents the difference factor in the seam height at the current moment.

[0015] In one embodiment, the method for determining the joint defect index at the current moment based on the joint gap difference factor and the joint height difference factor, and for determining whether the process parameters at the current moment need to be corrected based on the joint defect index, is as follows:

[0016] Take the absolute values ​​of the joint gap difference factor and the joint height difference factor, and use the maximum value of the absolute values ​​of the joint gap difference factor and the joint height difference factor as the joint defect index at the current moment.

[0017] A preset joint gap threshold is set. When the joint gap defect index is greater than or equal to the preset joint gap threshold, the process parameters at the current moment need to be corrected.

[0018] In one embodiment, the method for obtaining the joint gap defect factor and joint height defect factor for each defect by comparing the joint gap and joint height of each defect with the joint gap and joint height of the same process parameters under the defect-free condition is as follows:

[0019] The difference between the gap of the defective joint and the gap of the corresponding flawless joint is processed by the hyperbolic tangent function to obtain the joint gap defect factor; the difference between the joint height of the defective joint and the joint height of the corresponding flawless joint is processed by the hyperbolic tangent function to obtain the joint height defect factor.

[0020] In one embodiment, the method for obtaining the general joint gap difference and general joint height difference of such defects based on the joint gap defect factor and joint height defect factor of all defects in the same type of defect is as follows:

[0021] Δc δ,i This represents the joint gap defect factor at the i-th defect location in defect type δ. m(Δc) represents the arithmetic mean of the defect factors for all joint gaps in defect type δ; δ,i ) represents the mode of all joint gap defect factors in defect type δ; o(Δc δ,i) represents the median of the joint gap defect factor for all defect types δ; Δh δ,i This represents the seam height defect factor at the i-th defect location in defect type δ. m(Δh) represents the arithmetic mean of all seam height defect factors in defect type δ. δ,i ) represents the mode of all seam height defect factors in defect type δ; o(Δh) δ,i ) represents the median of the seam height defect factor for all defect types δ; C δ H represents the common joint gap difference corresponding to defect type δ; δ The general high defect factor corresponding to defect type δ.

[0022] In one embodiment, the method for determining the potential defect index at the current moment based on the similarity between the vectors of the current seam gap difference factor and the seam height difference factor and the vectors of the general seam gap difference and the general seam height difference is as follows:

[0023] For the current moment, construct the current difference vector using the joint gap difference factor and the joint height difference factor as two dimensions. Then, based on the common gap difference C for each defect type... δ The difference in seam height H from the general seam height δ Constructing a defect vector

[0024] The cosine similarity between the current difference vector and the defect probability vector is calculated as an index representing the probability of defects at the current moment.

[0025] In one embodiment, the method for obtaining the reasonable joint gap and reasonable joint height at the current moment by weighting the common joint gap difference and common joint height difference based on the defect probability index to correct the standard joint gap and standard joint height is as follows:

[0026] c0 represents the standard joint gap corresponding to the preset process parameters, C γ H represents the common joint gap difference corresponding to the γth defect, h0 represents the standard joint height corresponding to the preset process parameters, and H represents the joint height. γ Let γ represent the common seam height difference corresponding to the γth defect, E represent the type of defect, and tanh -1 This represents the inverse operation of the hyperbolic tangent function, m w,γ c represents the possible weight of the γ-th defect at the current time. ′ w h represents the reasonable joint gap at the current moment. ′ w This indicates the reasonable joint height at the current moment.

[0027] In one embodiment, the method for obtaining the corrected welding current and corrected arc voltage by modifying the process parameters at the current moment based on the process parameters when there are no defects in the historical data for reasonable joint gap and reasonable joint height is as follows:

[0028] The moment corresponding to the flawless process parameters of reasonable joint gap and reasonable joint height obtained from historical data is recorded as the flawless moment; the ratio of the reciprocal of the time interval between each flawless moment and the current moment to the sum of the reciprocals of the time intervals between all flawless moments and the current moment is used as the time weight of each flawless moment.

[0029] The expressions for the corrected welding current and the corrected arc voltage are:

[0030] I v U represents the welding current at the v-th flawless moment. v T represents the arc voltage at the v-th flawless moment. v Let I represent the time weight of the v-th flawless moment, D represent the number of flawless moments, and I represent the time weight of the v-th flawless moment. ′ w U represents the corrected welding current at the current moment. ′ w This represents the corrected arc voltage at the current moment.

[0031] Secondly, embodiments of this application also provide a straight seam steel pipe welding apparatus, including a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor executes the computer program to implement the steps of any of the above-described straight seam steel pipe welding methods. Attached Figure Description

[0032] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart of a straight seam steel pipe welding method provided in one embodiment of this application. Detailed Implementation

[0034] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a straight seam steel pipe welding method and welding apparatus proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0036] An embodiment of a straight seam steel pipe welding method and welding apparatus:

[0037] The following description, in conjunction with the accompanying drawings, details a specific scheme for a straight seam steel pipe welding method and welding apparatus provided in this application.

[0038] Please see Figure 1 The diagram illustrates a flowchart of a straight seam steel pipe welding method according to an embodiment of this application, which includes the following steps:

[0039] Step S001: Collect the values ​​of process parameters, joint gap, and joint height at each moment.

[0040] Numerous sensors are installed in the welding system of the pre-welding machine to detect the welding quality and related conditions at the joint of the tube blank before welding.

[0041] The sensors placed include: current sensors, voltage sensors, laser sensors, gap sensors, and displacement sensors.

[0042] In this embodiment, data is collected every 1 second. The arc voltage and welding current are collected by current and voltage sensors, and the welding current and arc voltage are recorded as process parameters. The welding speed is obtained based on the displacement sensor and time, and the joint gap and joint height are obtained based on the gap sensor. The laser sensor is used to scan the welding position. Since the welding is adjusted while welding in this application, the position scanned by the laser is the target position, and the time when the target position is scanned is recorded as the current time.

[0043] At this point, the values ​​of the process parameters, as well as the joint gap and joint height, were obtained at each moment.

[0044] Step S002: Obtain the preset process parameters and their corresponding standard process parameters. Determine the joint defect index based on the difference between the standard process parameters and the process parameters at the current time, and determine whether correction is needed.

[0045] This application is based on JCO forming technology to roll steel plates into tube blanks. The gap of the joint formed by the tube blanks will approach a certain size. After the steel plate is bent to form the tube blanks, there will be a joint. It is unavoidable that there will be a height difference on both sides of the joint and the joint gap will not be uniform. This means that the welding process parameters of the previous moment cannot be used for the next moment. The process parameters need to be adjusted according to the joint situation.

[0046] When the weld seam changes, using the previous process parameters may fail to achieve the original welding target if there is a significant height difference between the two sides of the weld seam and the original welding current and voltage are insufficient. However, if the weld seam suddenly narrows, the original welding current and voltage may be too high, causing the molten pool to expand and accumulate more metal, resulting in weld beads or burn-through. Therefore, by analyzing the condition of the weld seam on the tube blank and the condition of the previous weld seams, the process parameters for the subsequent weld seam are constructed.

[0047] First, for each process parameter, the average of the historical process parameter values ​​is used as the preset value for that process parameter. In this embodiment, the average of the G process parameter values ​​before the current moment is taken as the value of the process parameter at the current moment, where G is set to 100.

[0048] This allows us to obtain the preset process parameters for the current moment.

[0049] Due to slight differences in steel plate material and processing techniques, or accidental errors, some joints may be too small or have excessive height differences, differing from the typical joint conditions of the tube blank. This means that using the original welding parameters may not be sufficient for welding the tube blank joints effectively. Therefore, by obtaining the reasonable joint gap and height under preset process parameters and comparing them with the current joint gap and height, it can be determined whether the current process parameters are suitable.

[0050] In this embodiment, the data from the previous 3 days is used as the historical dataset. The joint gap and joint height corresponding to the preset process parameter in the historical dataset are obtained. The average joint gap and the average joint height corresponding to the preset process parameter in the historical dataset are taken as the standard joint gap and standard joint height corresponding to the preset process parameter, respectively.

[0051] The consequences of increasing and decreasing the weld seam size differ. When the weld seam is larger, using the original welding parameters, there is less metal in the molten pool, and a large amount of heat cannot dissipate, leading to burn-through. Conversely, when the weld seam is smaller, the molten pool becomes relatively larger, containing more metal and forming weld beads. Therefore, the calculation of weld seam differences needs to be directional.

[0052] Based on the differences between the standard joint gap and standard joint height corresponding to the preset process parameters and the joint gap and joint height at the current moment, the joint gap difference factor and joint height difference factor at the current moment are obtained. The specific expressions are:

[0053] Δc w =tanh(c w -c0), Δh w =tanh(h) w -h0), c w c0 represents the current joint gap, and h represents the standard joint gap corresponding to the preset process parameters. w The current joint height is represented by h0, which represents the standard joint height corresponding to the preset process parameters. tanh() represents the hyperbolic tangent function, and Δc... w Δh represents the difference factor in the joint gap at the current moment. w This represents the seam height difference factor at the current moment. Where Δc w and Δh w The range of values ​​for is (-1, 1).

[0054] Since any deviation from the preset conditions will affect the welding, the joint defect index is determined based on the joint gap difference factor and joint height difference factor at the current moment. The expression for the joint defect index is as follows:

[0055] R w =max(|Δc w |,|Δh w |), Δc w Δh represents the difference factor in the joint gap at the current moment. w Represents the seam height difference factor at the current moment, max() represents the maximum value function, R w This indicates the current seam defect index.

[0056] A preset seam threshold is set. When the seam defect index is greater than or equal to the seam threshold, it is considered that the seam is not suitable for the preset process parameters at the current moment, and the value of the process parameters at the current moment needs to be corrected. If the seam defect index is less than the seam threshold, the preset process parameters are directly used as the process parameters at the current moment.

[0057] At this point, it is determined whether the current process parameters need to be adjusted.

[0058] Step S003: Determine the general joint gap difference and general joint height difference of a class of defects based on the difference between the joint condition of each defect in a class of defects and the joint condition of a defect-free class of defects with the same process parameters; determine the possible defect index by the similarity with the current moment; obtain a reasonable joint condition based on the possible defect index, and obtain the corrected welding current and corrected arc voltage.

[0059] The above steps compare the joint condition under preset process parameters with the joint condition at the current moment to determine whether the preset process parameters are applicable at the current moment. If the preset process parameters are not applicable, various problems will occur at the current joint, leading to poor welding. In order to adjust to suitable process parameters, it is necessary to analyze what specific phenomena will occur, and then adjust the process parameters based on the corresponding phenomena.

[0060] Throughout the history of welding, various defects have occurred due to the failure to adjust process parameters in a timely manner. These defects are recorded. Since different defects have different visual appearances, all defects are marked and classified based on image vision technology to obtain the types of all defects and the process parameters of each defect.

[0061] For defects of the same type, the process parameters, joint gap, and joint height for each defect are statistically analyzed. The joint gap and joint height for each defect under the same process parameters are also statistically analyzed, as well as the joint gap and joint height for the corresponding process parameters when there are no defects.

[0062] For the same type of defect, based on the differences in joint gap and joint height between each defect and the defect-free joint with the same process parameters, the joint gap difference factor and joint height difference factor corresponding to each defect are obtained. Specifically, the difference between the joint gap of the defect and the corresponding joint gap of the defect-free joint is processed by the hyperbolic tangent function to obtain the joint gap defect factor; the difference between the joint height of the defect-free joint and the corresponding joint height of the defect-free joint is processed by the hyperbolic tangent function to obtain the joint height defect factor.

[0063] Most defects arise from mismatches between the seam condition and welding parameters. However, different defects manifest differently, leading to varying seam differences. Since defects are inherently categorized, the cause of a defect can be determined by examining the differences between the seam condition and the corresponding welding parameters for each defect type.

[0064] Therefore, for this type of defect, the joint gap difference factor and joint height difference factor are calculated for each defect. Based on this, the general joint gap difference and general joint height difference for this type of defect are obtained, expressed as follows: Δc δ,i This represents the joint gap defect factor at the i-th defect location in defect type δ. m(Δc) represents the arithmetic mean of the defect factors for all joint gaps in defect type δ; δ,i ) represents the mode of all joint gap defect factors in defect type δ; o(Δc δ,i) represents the median of the joint gap defect factor for all defect types δ; Δh δ,i This represents the seam height defect factor at the i-th defect location in defect type δ. m(Δh) represents the arithmetic mean of all seam height defect factors in defect type δ. δ,i ) represents the mode of all seam height defect factors in defect type δ; o(Δh) δ,i ) represents the median of the seam height defect factor for all defect types δ; C δ H represents the common joint gap difference corresponding to defect type δ; δ The general high defect factor corresponding to defect type δ.

[0065] If the difference between the current gap at the joint and the gap corresponding to the preset process parameters is similar to the common difference corresponding to a certain defect, it indicates that the current joint may also cause the situation corresponding to that defect. Based on this, calculate the defect probability index M corresponding to each defect at the current moment. w,δ .

[0066] For the current moment, construct the current difference vector using the joint gap difference factor and the joint height difference factor as two dimensions. Then, based on the common gap difference C for each defect type... δ The difference in seam height H from the general seam height δ Constructing a defect vector

[0067] The cosine similarity between the current difference vector and the potential defect vector is calculated as an indicator of the likelihood of a defect at the current moment. The higher the cosine similarity, the closer the vectors are, which means that the defect at the current moment is more likely to be of this type.

[0068] When collecting the joint gap and joint height at the current moment, scratches from the manufacturing process may cause inaccuracies in the collected figures. Therefore, it is necessary to correct the joint gap and joint height at the current moment based on their similarity to different defects. The ratio of the possible defect index corresponding to each defect to the sum of all possible defect indices is used as the defect probability weight for each defect. Since the comparison of defects is with the comparison of defect-free conditions, the joint gap and joint height obtained based on the preset parameter of defect-free conditions are corrected using the following expression:

[0069] c0 represents the standard joint gap corresponding to the preset process parameters, C γ H represents the common joint gap difference corresponding to the γth defect, h0 represents the standard joint height corresponding to the preset process parameters, and H represents the joint height. γ Let γ represent the common seam height difference corresponding to the γth defect, E represent the type of defect, and tanh-1 This represents the inverse operation of the hyperbolic tangent function, m w,γ c represents the possible weight of the γ-th defect at the current time. ′ w h represents the reasonable joint gap at the current moment. ′ w This indicates the reasonable joint height at the current moment.

[0070] Based on the above steps, the reasonable joint gap and reasonable joint height at the current moment are obtained. The time corresponding to the flawless process parameters for the reasonable joint gap and reasonable joint height in the historical data is recorded as the flawless moment. The time interval between each flawless moment and the current moment is obtained. The smaller the time interval, the greater the impact. Therefore, the reciprocal of the time interval is used as the weight to weight the process parameters of each flawless moment to obtain the corrected welding current and corrected arc voltage.

[0071] Specifically, the ratio of the reciprocal of the time interval between each flawless moment and the current moment to the sum of the reciprocals of the time intervals between all flawless moments and the current moment is taken as the time weight of each flawless moment, expressed as: I v U represents the welding current at the v-th flawless moment. v T represents the arc voltage at the v-th flawless moment. v Let I represent the time weight of the v-th flawless moment, D represent the number of flawless moments, and I represent the time weight of the v-th flawless moment. ′ w U represents the corrected welding current at the current moment. ′ w This represents the corrected arc voltage at the current moment.

[0072] At this point, the corrected welding current and corrected arc voltage have been obtained.

[0073] Step S004: Perform welding according to the modified welding current and modified welding voltage.

[0074] When the pre-welding machine is running, and the laser sensor detects the current joint, the welding process parameters of the current joint during welding can be obtained according to the above steps, and welding can be completed according to the corresponding welding process parameters.

[0075] As the straight seam steel pipe is fed in, the laser sensor continues to detect, but the preset process parameters have changed. The current preset process parameters are those detected by the laser sensor at the seam in the previous moment. Therefore, the corrected welding current and corrected arc voltage at the current seam position are the preset welding parameters for the next seam position. These are then used as the preset process parameters for analysis to determine the corrected welding parameters for the next moment.

[0076] Based on the same inventive concept as the above method, this embodiment of the invention also provides a straight seam steel pipe welding apparatus, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above-described straight seam steel pipe welding methods.

[0077] It should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

[0078] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

Claims

1. A method of welding a straight-seam steel pipe, characterized by, The method comprises the following steps: Collecting the values of the process parameters at each welding moment, and the joint gap and the joint height; the process parameters include welding current and arc voltage; Obtaining a preset process parameter at the current moment based on the average of the process parameters at a preset number of moments before the current moment; obtaining a standard joint gap and a standard joint height corresponding to the preset process parameter based on historical data; obtaining a joint gap difference factor and a joint height difference factor based on the difference between the standard joint gap and the standard joint height and the joint gap and the joint height at the current moment; determining a joint defect index at the current moment based on the joint gap difference factor and the joint height difference factor, and judging whether the process parameter at the current moment needs to be corrected according to the joint defect index; Obtaining different types of defects and the process parameters of each defect based on historical data, obtaining a joint gap defect factor and a joint height defect factor of each defect based on the difference between the joint gap and the joint height of each defect and the joint gap and the joint height under the same process parameters without defects; obtaining a general joint gap difference and a general joint height difference of the same type of defects based on the joint gap defect factor and the joint height defect factor of all defects in the same type of defects; for the process parameter that needs to be corrected, determining a defect possibility index at the current moment according to the similarity between the vector of the joint gap difference factor and the joint height difference factor at the current moment and the vector of the general joint gap difference and the general joint height difference; correcting the standard joint gap and the standard joint height based on the weighted general joint gap difference and the general joint height difference according to the defect possibility index to obtain a reasonable joint gap and a reasonable joint height at the current moment; correcting the process parameter at the current moment based on the reasonable joint gap and the reasonable joint height and the process parameter without defects in the historical data to obtain a corrected welding current and a corrected arc voltage; Welding according to the corrected welding current and the corrected arc voltage.

2. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for obtaining the standard joint gap and the standard joint height corresponding to the preset process parameter based on historical data is: Obtaining the process parameters and the joint gap and the joint height at a plurality of moments before the current moment; counting the same process parameters as the preset process parameter, and taking the average of the joint gap and the joint height of the same process parameters as the standard joint gap and the standard joint height, respectively.

3. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for obtaining the joint gap difference factor and the joint height difference factor based on the difference between the standard joint gap and the standard joint height and the joint gap and the joint height at the current moment is: Δc w = tanh(c w -c0), Δh w = tanh(h w -h0), c w represents the joint gap at the current time, c0represents the standard joint gap corresponding to the preset process parameter, h w represents the joint height at the current time, h0represents the standard joint height corresponding to the preset process parameter, tanh() represents the hyperbolic tangent function, Δc w represents the joint gap difference factor at the current time, Δh w represents the joint height difference factor at the current time.

4. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for determining the joint defect index at the current moment based on the joint gap difference factor and the joint height difference factor, and judging whether the process parameter at the current moment needs to be corrected according to the joint defect index is: Taking the absolute value of the joint gap difference factor and the absolute value of the joint height difference factor, and taking the maximum value of the absolute value of the joint gap difference factor and the absolute value of the joint height difference factor as the joint defect index at the current moment; A preset joint threshold value, when the joint defect index is greater than or equal to the preset joint threshold value, the process parameter at the current moment needs to be corrected.

5. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for obtaining the seam gap defect factor and the seam height defect factor of each defect by taking the difference between the seam gap and the seam height of each defect and the seam gap and the seam height of the same process parameters in the case of no defect is: The difference between the seam gap of the defect and the corresponding seam gap without defect is processed by the hyperbolic tangent function to obtain the seam gap defect factor; the difference between the seam gap height of the defect and the corresponding seam gap height without defect is processed by the hyperbolic tangent function to obtain the seam height defect factor.

6. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for obtaining the general seam gap difference and the general seam height difference of the same type of defects according to the seam gap defect factors and the seam height defect factors of all defects in the same type of defects is: Δc δ,i represents the joint gap flaw factor at the i-th flaw in flaw type δ, represents the arithmetic mean of all joint gap flaw factors in flaw type δ; m(Δc δ,i ) represents the mode of all joint gap flaw factors in flaw type δ; o(Δc δ,i ) represents the median of all joint gap flaw factors in flaw type δ; Δh δ,i represents the joint height flaw factor at the i-th flaw in flaw type δ, represents the arithmetic mean of all joint height flaw factors in flaw type δ; m(Δh δ,i ) represents the mode of all joint height flaw factors in flaw type δ; o(Δh δ,i ) represents the median of all joint height flaw factors in flaw type δ; C δ represents the universal joint gap difference corresponding to flaw type δ; H δ represents the universal height flaw factor corresponding to flaw type δ.

7. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for determining the defect possibility index at the current time according to the similarity between the vector of the seam gap difference factor and the seam height difference factor at the current time and the vector of the general seam gap difference and the general seam height difference is: For the current time, a current difference vector is constructed with the seam gap difference factor and the seam height difference factor as two dimensions Further according to the common seam gap difference value C of each flaw type δ and the common seam height difference value H δ A flaw possibility vector is constructed The cosine similarity between the current difference vector and the defect possibility vector is calculated as the defect possibility index at the current time.

8. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for modifying the standard seam gap and the standard seam height based on the defect possibility index and the general seam gap difference and the general seam height difference to obtain the reasonable seam gap and the reasonable seam height at the current time is: c0 represents the standard joint gap corresponding to the preset process parameters, C γ h0 represents the standard joint height corresponding to the preset process parameters, H γ h0 represents the standard joint height corresponding to the preset process parameters, H -1 E represents the type of the defect, tanh w,γ E represents the type of the defect, tanh ′ w h represents the reasonable joint gap at the current moment ′ w h represents the reasonable joint height at the current moment 9. A method of welding a straight-seam steel pipe as set forth in claim 1, characterized by The method for modifying the current process parameters based on the reasonable seam gap and the reasonable seam height and the process parameters in the history data without defect to obtain the modified welding current and the modified arc voltage is: The time corresponding to the process parameters corresponding to the reasonable seam gap and the reasonable seam gap height in the history data without defect is recorded as the defect-free time; the reciprocal of the time interval between each defect-free time and the current time is taken as the time weight of each defect-free time. The expression of the modified welding current and the modified arc voltage is: I v the welding current at the vth instant of time, U v the arc voltage at the vth instant of time, T v the time weight at the vth instant of time, D ′ w the corrected welding current at the current instant of time, U ′ w the corrected arc voltage at the current instant of time.

10. A straight seam steel pipe welding apparatus comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, The processor executes the computer program to realize the steps of the straight seam steel pipe welding method according to any one of claims 1-8. The processor executes the computer program to realize the steps of the straight seam steel pipe welding method according to any one of claims 1-8.

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