A welding adaptive process method

Abstract

The invention discloses a welding adaptive process method. The invention can select a matching process according to the groove characteristics of a workpiece to adjust the swing speed, swing width, swing welding step length, wire feeding speed, current, voltage, etc., so as to control the welding filling amount to increase or decrease accordingly, ensure the layer height and welding forming effect, achieve an ideal state, and adapt to the requirements of automated mass production.

Description

Technical Field

[0001] The invention relates to the technical field of welding technology, and in particular to a welding adaptive process method. Background Art

[0002] In the actual automated welding process, there are reasons such as uneven workpiece surface, slight deformation of the groove plane, fluctuation of the gap distance at the groove, slight difference in the groove angle, etc., which affect the welding effect. It is necessary to immediately select a matching process according to the welding position to adjust the swing speed, swing width, swing welding step length, wire feeding speed, current, voltage, etc., to control the increase or decrease of the welding filling amount, ensure the layer height and welding forming effect, achieve the ideal state, and adapt to the requirements of automated mass production. Summary of the invention

[0003] The present invention provides a welding adaptive process method, which can solve the problems pointed out in the background technology.

[0004] A welding adaptive process method comprises the following steps:

[0005] S1. Obtain a visual scanning point cloud image of the groove of the workpiece to be welded, divide it into multiple sub-grooves, and extract groove features and groove size parameters respectively;

[0006] S2. Perform process matching on each section of the groove, select processes that meet the characteristic range, and combine multiple processes into a welding process for the groove of the workpiece;

[0007] S3. Calculate the weld bead position and the weaving welding width in the multi-segment sub-groove section according to the groove size parameters and groove characteristics;

[0008] S4. Calculate the cross-sectional area of ​​the weld and the welding speed according to the groove size parameters, groove characteristics and process parameters;

[0009] S5. The calculated welding speed, welding width and welding step length are used as the welding speed, welding width and welding step length of the welding process of the groove of the workpiece, and the welding work of the groove is performed.

[0010] The groove size parameters at least include: groove type, groove gap, groove angle;

[0011] The groove features at least include: groove reference point, groove depth, groove gap, groove angle, groove growth direction, groove multi-plane line;

[0012] The process parameters include at least: wire feeding speed, wire material, wire diameter, weaving step length and weaving frequency.

[0013] The process selection method in S2 is as follows:

[0014] The groove features are matched with the corresponding groove feature ranges of various processes in the process library. Based on the weights assigned to the features, the sum of the weight values ​​of various processes is calculated, and the process with the highest weight value is selected as the welding process for this section of the groove.

[0015] The calculation process of the weld bead position and the weaving weld width in the segmented section of S3 is as follows:

[0016] Calculate the relative position within the groove section :

[0017]

[0018] in, is the percentage of floor height, is the groove depth;

[0019] Based on the groove reference point and the translation vector of the weld bead relative to the reference point , get the point position on the layer where the weld is located ;

[0020] Known groove growth direction vector n, weld point position , the vector perpendicular to the groove growth direction is expressed as ;

[0021] Weld pass point Draw a straight line perpendicular to the growth direction of the groove ;

[0022] Based on the straight line Fitted curve of the left side of the intersecting groove features And the fitting curve on the right side , get two intersection points, calculate the distance between the two intersection points, the two intersection points are and , the distance between the two points is the width of the layer ;

[0023]

[0024] Get the weld width percentage based on the size parameter , calculate the weld width :

[0025]

[0026] Based on weld bead width And the points on the layer where the weld is located Get weld bead position .

[0027] Width-based adjustment factor , calculate the weaving width :

[0028]

[0029] The calculation method of weld cross-sectional area in S4 is as follows:

[0030] If the weld has curvature on both sides of the layer in the groove, then based on the weld position obtained by S3, the layer where the weld is located is taken as the center, and the normal straight line of the lowest point is set as , let the top point normal straight line be , let the left side curve be , let the right side curve be , the lowest point French straight line With the left side curve and right side curve The intersection points are and , the top point French straight line With the left side curve and right side curve The intersection points are and ,calculate and The spacing and and The spacing can be used to obtain the upper and lower widths. and bottom width ;

[0031] Connect in sequence , , and , forming a quadrilateral with a known height of , calculate the area of ​​the quadrilateral :

[0032]

[0033] in, is the weld width percentage, the weld width percentage of the first layer at the bottom is 100%;

[0034] curve Expressed as ;pass and Constructing a straight line ,straight line Expressed as , calculation curve and straight line The area enclosed :

[0035]

[0036] pass and Constructing a straight line , and the curve is calculated based on the same method and straight line The area enclosed ;

[0037] Calculate the cross-sectional area of ​​the weld bead :

[0038]

[0039] The calculation method of weld cross-sectional area in S4 is as follows:

[0040] If the weld bead is a straight line on both sides of the layer in the groove, then based on the weld bead position obtained by S3, the layer where the weld bead is located is taken as the center, and the bottom layer point normal straight line is set to , let the top point normal straight line be , let the left point be the French straight line , let the right point be the normal straight line , the lowest point French straight line French straight line with left point and the French straight line from the right point The intersection points are and , the top point French straight line French straight line with left point and the French straight line from the right point The intersection points are and ,calculate and The spacing and and The spacing can be used to obtain the upper and lower widths. and bottom width ;

[0041] The known height is , calculate the area of ​​the region enclosed by the four straight lines

[0042]

[0043] It is the cross-sectional area of ​​the weld in the current section.

[0044] The calculation method of welding speed is as follows:

[0045] The segment spacing is known to be , calculate the relative gentle filling amount :

[0046]

[0047] Calculate the filling volume per second in this segment based on the wire diameter and wire feeding speed used in the selected process :

[0048]

[0049] in, is the wire diameter, is the wire feeding speed;

[0050] Based on fill volume per second And the filling amount Available welding speed for:

[0051]

[0052] Welding step length of the process selected in S2 The calculation formula is as follows:

[0053]

[0054] in, is the welding speed, is the welding frequency.

[0055] The welding step length of the process selected in S2 adopts a fixed step length .

[0056] Preferably, the method for adjusting the welding wire speed calculated by S4 is as follows:

[0057] Based on welding speed adjustment factor , calculate the actual welding speed :

[0058]

[0059] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention can select a matching process according to the groove characteristics of the workpiece to adjust the swing speed, swing width, swing welding step length, wire feeding speed, current, voltage, etc., so as to control the welding filling amount to increase or decrease accordingly, ensure the layer height and welding forming effect, achieve an ideal state, and adapt to the requirements of automated mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a schematic diagram of the cross-sectional characteristics and weld bead of the V-shaped groove of the present invention;

[0061] Figure 2 It is a schematic diagram of the U-shaped groove cross-section characteristics and weld bead of the present invention;

[0062] Figure 3 This is a segmented image of the workpiece scan of the present invention. DETAILED DESCRIPTION

[0063] A specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation.

[0064] like Figure 1 and Figure 3 As shown, an embodiment of the present invention provides a welding adaptive process method, comprising the following steps:

[0065] S1. Obtain a visual scanning point cloud image of the groove of the workpiece to be welded, divide it into multiple sub-grooves, and extract groove features and groove size parameters respectively;

[0066] Figure 1 1-15 in the middle are multiple sub-slopes;

[0067] The groove dimension parameters include at least: groove type, groove gap, groove angle;

[0068] The groove features include at least: groove reference point , groove depth , groove gap, groove angle, groove growth direction vector n, groove multi-plane line;

[0069] The process parameters include at least: wire feeding speed, wire material, wire diameter, weaving step length and weaving frequency;

[0070] For workpieces with complex conditions, small-spacing segments can be used to adapt to different processes and weld out suitable forming effects; for relatively standard workpieces, the segment spacing can be increased to increase efficiency;

[0071] S2. Perform process matching on each section of the groove, select processes that meet the characteristic range, and combine multiple processes into a welding process for the groove of the workpiece;

[0072] That is, the following process matching is performed for each section of the groove: according to the groove characteristics, the features are compared one by one in the bound process library, and the appropriate process is selected; there are multiple processes in the process library, and each process is equipped with a corresponding feature value, and it has a range; if the features extracted from the workpiece meet the feature range of the process, then the process is hit; then according to the weights assigned to the features, the sum of the weight values ​​of the process is calculated, and the process with the highest weight value is selected as the process used for the groove welding (the specific matching conditions and features can be set according to the groove type; the weight value of each matching condition is set according to the process requirements).

[0073] For example, if the groove angle in the process is [43,47] and the groove angle of the workpiece is 45, it is a hit;

[0074] According to the weight setting, if the hit is 3, the weight is 1 if it is exactly the boundary value (43 / 47, which can be rounded or set to a fluctuation range), and the weight is 0 if it exceeds the range;

[0075] If the groove angle and groove depth are used as the matching conditions, the sum of the weight values ​​of each process is calculated and the process with the highest weight value is selected.

[0076] S3. According to the groove size parameters and groove characteristics, the weld bead position and the swing welding width in the multi-segment groove section are calculated respectively. Different welds need to process the upper and lower bottom widths according to the weld bead width percentage to obtain a more accurate weld bead cross-sectional area;

[0077] The specific calculation process is as follows:

[0078] Calculate the relative position within the groove section :

[0079]

[0080] in, is the percentage of floor height, is the groove depth;

[0081] Based on the groove reference point and translation vectors (like Figure 1 , in the cross section, the position of each weld bead relative to the reference point can be regarded as a translation vector), calculate the relative position of the layer where the weld bead is located, and obtain the point position on the layer ;

[0082] Known groove growth direction vector n, weld point position , the vector perpendicular to the growth direction is expressed as ; Perpendicular to the growth direction; Use this to calculate the layer width and weld bead width;

[0083] Pass this point Draw a straight line perpendicular to the growth direction of the groove ;

[0084] like Figure 1 As shown, the groove of this embodiment is a V-shaped groove, based on the straight line Fitted straight line of the A surface of the intersecting groove feature And the fitting straight line of surface B , get two intersection points, calculate the distance between the two intersection points, the two intersection points are and , the distance between the two points is the width of the layer ;

[0085]

[0086] Get the weld width percentage based on the size parameter , calculate the weld width :

[0087]

[0088] Based on weld bead width And the points on the layer where the weld is located Get weld bead position .

[0089] Width-based adjustment factor , calculate the weaving width :

[0090]

[0091] S4. Calculate the cross-sectional area of ​​the weld and the welding speed according to the groove size parameters, groove characteristics and the selected process parameters;

[0092] The specific calculation method is as follows:

[0093] Knowing the layer where the weld is located and the arrangement order in the layer, the weld position can be obtained ;

[0094] Given the percentage of each layer's height, taking the current layer as the center, we can know the percentage of the upper and lower layers. , , calculate the upper and lower layer positions, then the upper and lower limits of the layer can be known; and the direction of the layer is perpendicular to the growth direction of the groove, so the normal straight line of the lowest layer point is expressed as , the top point French straight line is expressed as ,

[0095] Known weld bead location , weld bead width , the left point French straight line is represented by , the right point French straight line is expressed as , the above four straight lines form a quadrilateral;

[0096] French straight line at the bottom point French straight line with left point and the French straight line from the right point The intersection points are and , the top point French straight line French straight line with left point and the French straight line on the right The intersection points are and ,calculate and The spacing and and The spacing can be used to obtain the upper and lower widths. and bottom width ;

[0097] The known height is , calculate the area of ​​the region enclosed by the four straight lines :

[0098]

[0099] That is, the cross-sectional area of ​​the weld in the current section;

[0100] This is the cross-sectional area of ​​the weld bead of the first layer groove 1 at the bottom. The weld bead width percentage is 100%. The weld bead width percentages of the other sub-grooves are not 100%. The upper and lower bottom widths need to be processed according to the weld bead width calculation method, that is, and ;

[0101] The segment spacing is known to be , calculate the relative gentle filling amount :

[0102]

[0103] Calculate the filling volume per second in this segment based on the wire diameter and wire feeding speed used in the selected process :

[0104]

[0105] in, is the wire diameter, is the wire feeding speed; (the calculation here is a theoretical value, the actual wire feeding speed is related to the robot posture and welding equipment, and there will be some loss; the welding speed adjustment coefficient df below can be adjusted to be closer to the actual production environment);

[0106] Based on fill volume per second And the filling amount Available welding speed for:

[0107]

[0108] S5, using the calculated welding speed, welding width, and welding step length as the welding speed, welding width, and welding step length of the welding process of the groove of the workpiece, and performing the welding work of the groove;

[0109] The welding wire speed of each sub-groove is not the same, and each is used as the welding speed of the process matched therewith. According to the sequence of the sub-groove, multiple processes are combined to obtain a complete welding process of the workpiece groove;

[0110] In addition, add welding speed adjustment parameters , in order to adapt to different processes in welding, there may be splashing, flowing and other conditions in the molten pool, and the actual welding speed after adjustment :

[0111]

[0112] In addition, the welding step length of the process selected in S2 can adopt a fixed step length Or use a fixed welding frequency and calculate the welding step length for each section, that is, set the step length The calculation formula is as follows:

[0113]

[0114] in, is the welding speed, is the welding frequency.

[0115] Embodiment 2

[0116] like Figure 2 As shown, the U-shaped groove is different from the V-shaped groove. The weld has an arc on both sides of the layer in the groove. Using the same calculation method will result in a large error. This embodiment proposes a welding adaptive process method applicable to the U-shaped groove on the basis of the first embodiment. The difference from the first embodiment is steps S3-S5. Only the two steps are described in detail below:

[0117] S3. Calculate the weld bead position and the weaving welding width in the multi-segment sub-groove section according to the groove size parameters and groove characteristics;

[0118] The specific calculation process is as follows:

[0119] Calculate the relative position within the groove section :

[0120]

[0121] in, is the percentage of floor height, is the groove depth;

[0122] Based on the groove reference point and translation vectors (like Figure 1 , in the cross section, the position of each weld bead relative to the reference point can be regarded as a translation vector), calculate the relative position of the layer where the weld bead is located, and obtain the point position on the layer ;

[0123] Known groove growth direction vector n, weld point position , the vector perpendicular to the growth direction is expressed as ; Perpendicular to the growth direction; Use this to calculate the layer width and weld bead width;

[0124] Pass this point Draw a straight line perpendicular to the growth direction of the groove ;

[0125] like Figure 2 The groove of this embodiment is a U-shaped groove, which is different from the V-shaped groove. Fitted curve of the left side of the intersecting groove features And the fitting curve on the right side , get two intersection points, calculate the distance between the two intersection points, the two intersection points are and , the distance between the two points is the width of the layer ;

[0126]

[0127] Get the weld width percentage based on the size parameter , calculate the weld width :

[0128]

[0129] Based on weld bead width And the points on the layer where the weld is located Get weld bead position .

[0130] Width-based adjustment factor , calculate the weaving width :

[0131]

[0132] S4. Calculate the cross-sectional area of ​​the weld and the welding speed according to the groove size parameters, groove characteristics and the selected process parameters;

[0133] The specific calculation method is as follows:

[0134] Knowing the layer where the weld is located and the arrangement order in the layer, the weld position can be obtained ;

[0135] Given the percentage of each layer's height, taking the current layer as the center, we can know the percentage of the upper and lower layers. , , calculate the upper and lower layer positions, then the upper and lower limits of the layer can be known; and the direction of the layer is perpendicular to the growth direction of the groove, so the normal straight line of the lowest layer point is expressed as , the top point French straight line is expressed as ,

[0136] Known weld bead location , weld bead width , the left side curve is , the right side curve is The above four straight lines form a quadrilateral;

[0137] French straight line at the bottom point The left side curve is and the right side curve is The intersection points are and , the top point French straight line The left side curve is and the right side curve is The intersection points are and ,calculate and The spacing and and The spacing can be used to obtain the upper and lower widths. and bottom width ;

[0138] Note: The layer where the weld bead is located in the groove has arcs on both sides, so the above method is applicable; if the side of the layer is close to a straight line, the calculation method of the V-groove can be used, directly using the plane fitting straight line to intersect with the upper / lower layer line, which is simpler;

[0139] The area enclosed by the two straight lines and the two curves can be divided into three regions, namely:

[0140] Connect in sequence , , and The area of ​​the quadrilateral formed ;

[0141] curve and straight line The area enclosed ;as well as

[0142] curve and straight line The area enclosed ;

[0143] The known height is , calculate the area :

[0144]

[0145] This is the cross-sectional area of ​​the weld bead of the first layer groove 1 at the bottom. The weld bead width percentage is 100%. The weld bead width percentages of the other sub-grooves are not 100%. The upper and lower bottom widths need to be processed according to the weld bead width calculation method, that is, and ;

[0146] Then the cross-sectional area of ​​the remaining grooves can be expressed as:

[0147]

[0148] curve Expressed as ;

[0149] pass and Constructing a straight line ,straight line Expressed as The intersection point of the two is and , calculation curve and straight line The area enclosed :

[0150]

[0151] pass and Constructing a straight line , the curve is calculated based on the same method and straight line The area enclosed ;

[0152] Finally calculate the cross-sectional area of ​​the weld bead :

[0153]

[0154] The segment spacing is known to be , calculate the relative gentle filling amount :

[0155]

[0156] Calculate the filling volume per second in this segment based on the wire diameter and wire feeding speed used in the selected process :

[0157]

[0158] in, is the wire diameter, is the wire feeding speed; (the calculation here is a theoretical value. The actual wire feeding speed is related to the robot posture and welding equipment, and there will be some loss. You can adjust the welding speed adjustment coefficient below , closer to the actual production environment);

[0159] Based on fill volume per second And the filling amount Available welding speed for:

[0160]

[0161] S5, using the calculated welding speed, welding width, and welding step length as the welding speed, welding width, and welding step length of the welding process of the groove of the workpiece, and performing the welding work of the groove;

[0162] The welding wire speed of each sub-groove is not the same, and each is used as the welding speed of the process matched therewith. According to the sequence of the sub-groove, multiple processes are combined to obtain a complete welding process of the workpiece groove;

[0163] In addition, add welding speed adjustment parameters , in order to adapt to different processes in welding, there may be splashing, flowing and other conditions in the molten pool, and the actual welding speed after adjustment :

[0164]

[0165] In addition, the welding step length of the process selected in S2 can adopt a fixed step length Or use a fixed welding frequency and calculate the welding step length for each section, that is, set the step length The calculation formula is as follows:

[0166]

[0167] in, is the welding speed, is the welding frequency.

[0168] In addition, although the above two embodiments take V-shaped groove and U-shaped groove as examples respectively, it does not mean that the welding adaptive process method of the present application can only be used for welding work on these two types of grooves. The technical solution of this embodiment can also be used for welding work on other types of grooves.

[0169] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A welding adaptive process method, characterized in that: The steps include: S1. Obtain a visual scanning point cloud image of the groove of the workpiece to be welded, divide it into multiple sub-grooves, and extract groove features and groove size parameters respectively; S2. Perform process matching on each section of the groove, select processes that meet the characteristic range, and combine multiple processes into a welding process for the groove of the workpiece; S3. Calculate the weld bead position and the weaving welding width in the multi-segment sub-groove section according to the groove size parameters and groove characteristics; S4. Calculate the cross-sectional area of ​​the weld and the welding speed according to the groove size parameters, groove characteristics and process parameters; S5, using the calculated welding speed, welding width, and welding step length as the welding speed, welding width, and welding step length of the welding process of the groove of the workpiece, and performing the welding work of the groove; The calculation process of the weld bead position and the weaving welding width in the segmented section in S3 is as follows: Calculate the relative position within the groove section : in, is the percentage of floor height, is the groove depth; Based on the groove reference point and the translation vector of the weld bead relative to the reference point , get the point position on the layer where the weld is located ; Known groove growth direction vector n, weld point position , the vector perpendicular to the groove growth direction is expressed as ; Weld pass point Draw a straight line perpendicular to the growth direction of the groove ; Based on the straight line Fitted curve of the left side of the intersecting groove features And the fitting curve on the right side , get two intersection points, calculate the distance between the two intersection points, the two intersection points are and , the distance between the two points is the width of the layer ; Get the weld width percentage based on the size parameter , calculate the weld width : Based on weld bead width And the points on the layer where the weld is located Get weld bead position Width-based adjustment factor , calculate the weaving width : The process selection method in S2 is as follows: Match the groove features with the corresponding groove feature ranges of various processes in the process library, calculate the sum of the weight values ​​of various processes based on the weights assigned to the features, and select the process with the highest weight value as the welding process for this section of the groove; The method for calculating the cross-sectional area of ​​the weld in S4 is as follows: If the weld has curvature on both sides of the layer in the groove, then based on the weld position obtained by S3, the layer where the weld is located is taken as the center, and the normal straight line of the lowest point is set as , let the top point normal straight line be , let the left side curve be , let the right side curve be , the lowest point French straight line With the left side curve and right side curve The intersection points are and , the top point French straight line With the left side curve and right side curve The intersection points are and ,calculate and The spacing and and The spacing can be used to obtain the upper and lower widths. and bottom width ; Connect in sequence , , and , forming a quadrilateral with a known height of , calculate the area of ​​the quadrilateral : in, is the weld width percentage, the weld width percentage of the first layer at the bottom is 100%; curve Expressed as ;pass and Constructing a straight line ,straight line Expressed as , calculation curve and straight line The area enclosed : pass and Constructing a straight line , and the curve is calculated based on the same method and straight line The area enclosed ; Calculate the cross-sectional area of ​​the weld bead :

2. The welding adaptive process method according to claim 1, characterized in that: The groove size parameters at least include: groove type, groove gap, groove angle; The groove features at least include: groove reference point, groove depth, groove gap, groove angle, groove growth direction, groove multi-plane line; The process parameters include at least: wire feeding speed, wire material, wire diameter, weaving step length and weaving frequency.

3. The welding adaptive process method according to claim 1, characterized in that: The method for calculating the cross-sectional area of ​​the weld in S4 is as follows: If the weld bead is a straight line on both sides of the layer in the groove, then based on the weld bead position obtained by S3, the layer where the weld bead is located is taken as the center, and the bottom layer point normal straight line is set to , let the top point normal straight line be , let the left point be the French straight line , let the right point be the normal straight line , the lowest point French straight line French straight line with left point and the French straight line on the right The intersection points are and , the top point French straight line French straight line with left point and the French straight line on the right The intersection points are and ,calculate and The spacing and and The spacing can be used to obtain the upper and lower widths. and bottom width ; The known height is , calculate the area of ​​the region enclosed by the four straight lines It is the cross-sectional area of ​​the weld in the current section.

4. The welding adaptive process method according to claim 1, characterized in that: The calculation method of the welding speed is as follows: The segment spacing is known to be , calculate the relative gentle filling amount : Calculate the filling volume per second in this segment based on the wire diameter and wire feeding speed used in the selected process : in, is the wire diameter, is the wire feeding speed; Based on fill volume per second And the filling amount Available welding speed for:

5. The welding adaptive process method according to claim 4, characterized in that: The welding step length of the process selected in S2 The calculation formula is as follows: in, is the welding speed, is the welding frequency.

6. The welding adaptive process method according to claim 1, characterized in that: The welding step length of the process selected in S2 adopts a fixed step length. .

7. The welding adaptive process method according to claim 4, characterized in that: The adjustment method of the welding wire speed calculated by S4 is as follows: Based on welding speed adjustment factor , calculate the actual welding speed :

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