Weld quality control method and system

Abstract

The present application relates to the technical field of welding, and provides a welding quality control method and system, which comprises the following steps: establishing a relationship database of welding process and welding quality; acquiring a gap parameter between at least two pieces to be welded before welding, adjusting a pre-pressing value before welding based on comparison of the gap parameter and a gap threshold value in the relationship database; acquiring an expansion volume parameter of a nugget at a welding spot during welding, adjusting a welding parameter during welding based on comparison of the expansion volume parameter and a nugget expansion threshold value in the relationship database; acquiring a nugget quality parameter of the nugget at the welding spot after welding is completed, and adjusting a post-processing parameter after welding based on comparison of the nugget quality parameter and a nugget quality threshold value in the relationship database. Thus, the welding quality requirement can be ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of welding technology, in particular to a welding quality control method and system. BACKGROUND

[0002] In the welding process, the welding parameters directly affect the welding quality of the workpiece after welding, and the welding parameters are generally set before welding, and cannot be adjusted in real time according to the actual welding situation during welding, resulting in low efficiency and quality of spot welding production. SUMMARY

[0003] The present application provides a welding quality control method to solve the technical problem that the welding parameters of the existing welding process cannot be adjusted in real time, resulting in low welding quality, realizes monitoring of the welding state and real-time adjustment of the parameters, and improves the spot welding quality.

[0004] The present application also provides a welding quality control system.

[0005] The present application provides a welding quality control method, comprising the following steps:

[0006] establishing a relationship database of welding process and welding quality;

[0007] obtaining a gap parameter between at least two pieces to be welded before welding, and adjusting a pre-pressing force value before welding based on a comparison between the gap parameter and a gap threshold value in the relationship database;

[0008] obtaining an expansion volume parameter of a nugget at a welding spot during welding, and adjusting a welding parameter during welding based on a comparison between the expansion volume parameter and a nugget expansion threshold value in the relationship database;

[0009] obtaining a nugget quality parameter of the nugget at the welding spot after welding, and adjusting a post-processing parameter after welding based on a comparison between the nugget quality parameter and a nugget quality threshold value in the relationship database.

[0010] According to the welding quality control method provided by the present application, the step of establishing a relationship database of welding process and welding quality specifically comprises:

[0011] establishing a relationship database of pre-pressing force, gap threshold value and welding quality before welding, establishing a relationship database of welding parameter, nugget expansion threshold value and welding quality during welding, and establishing a relationship database of post-processing parameter, nugget quality threshold value and welding quality after welding.

[0012] According to the welding quality control method provided by the present application, the step of obtaining a gap parameter between at least two pieces to be welded before welding specifically comprises:

[0013] The laser is emitted to the at least two pieces to be welded at the first position, and the laser is reflected on the surface of the at least two pieces to be welded and forms at least two reflected light rays, the at least two reflected light rays are received by the photosensitive element at the second position, and the at least two reflected light rays correspond to form at least two photosensitive positions on the photosensitive element, and the gap value between the at least two pieces to be welded is calculated based on the interval between the at least two photosensitive positions.

[0014] According to the welding quality control method provided by the application, the step of adjusting the pre-pressing value before welding based on the comparison between the gap parameter and the gap threshold value in the relational database specifically comprises:

[0015] If the value of the gap parameter is less than or equal to the gap threshold value in the relational database, the pre-pressing value before welding does not need to be adjusted.

[0016] If the value of the gap parameter is greater than the gap threshold value in the relational database, the pre-pressing value before welding is increased.

[0017] According to the welding quality control method provided by the application, the step of obtaining the expansion volume parameter of the nugget at the welding point during welding specifically comprises:

[0018] The expansion displacement sensor is additionally arranged at the welding end of the welding mechanism, and the expansion volume value of the nugget is detected by the expansion displacement sensor.

[0019] According to the welding quality control method provided by the application, the step of adjusting the welding parameter during welding based on the comparison between the expansion volume parameter and the nugget expansion threshold value in the relational database specifically comprises:

[0020] If the expansion volume parameter is within the range of the nugget expansion threshold value in the relational database, the welding parameter does not need to be adjusted.

[0021] If the expansion volume parameter is outside the range of the nugget expansion threshold value in the relational database, at least one of the welding current, the welding pressure, the electrode pressure, the welding time, the cooling time, the holding time and the pulse number is adjusted based on the relational database.

[0022] According to the welding quality control method provided by the application, the step of obtaining the nugget quality parameter of the nugget at the welding point after welding is completed specifically comprises:

[0023] The X-axis direction and the Y-axis direction of each welding point are scanned by the laser ranging device to form a rectangular scanning area, the height of all detection points in the rectangular scanning area is measured, and the three-dimensional profile is generated by cooperating with the value of the X-axis direction and the value of the Y-axis direction, and at least one of the crater depth and the profile diameter of the nugget is calculated based on the three-dimensional profile.

[0024] According to the welding quality control method provided by the application, the step of obtaining the nugget quality parameter of the nugget at the welding point after the welding is completed further comprises:

[0025] The ultrasonic scanning device is used to scan the welding point area, and at least one parameter of the nugget diameter and the quality defect at the nugget is calculated based on the result of the ultrasonic scanning.

[0026] According to the welding quality control method provided by the application, the step of adjusting the post-welding processing parameter based on the comparison between the nugget quality parameter and the nugget quality threshold in the relationship database specifically comprises:

[0027] If the nugget quality parameter is within the range of the nugget quality threshold in the relationship database, no post-welding processing is needed.

[0028] If the nugget quality parameter is outside the range of the nugget quality threshold in the relationship database, post-welding processing is needed.

[0029] The application further provides a welding quality control system, which comprises:

[0030] A database establishing unit is configured to establish a relationship database of welding processes and welding quality.

[0031] A first parameter obtaining unit is electrically connected to the database establishing unit and configured to obtain a gap parameter between at least two pieces of welding pieces before welding and compare the gap parameter with a gap threshold in the relationship database.

[0032] A first adjusting unit is electrically connected to the first parameter obtaining unit and configured to adjust a pre-pressing force value before welding based on the comparison between the gap parameter and the gap threshold in the relationship database.

[0033] A second parameter obtaining unit is electrically connected to the database establishing unit and configured to obtain an expansion volume parameter of the nugget at the welding point during the welding process and compare the expansion volume parameter with a nugget expansion threshold in the relationship database.

[0034] A second adjusting unit is electrically connected to the second parameter obtaining unit and configured to adjust a welding parameter during the welding based on the comparison between the expansion volume parameter and the nugget expansion threshold in the relationship database.

[0035] A third parameter obtaining unit is electrically connected to the database establishing unit and configured to obtain a nugget quality parameter of the nugget at the welding point after the welding is completed and compare the nugget quality parameter with a nugget quality threshold in the relationship database.

[0036] A third adjusting unit is electrically connected with the third parameter obtaining unit, and is configured to adjust a post-welding treatment parameter based on comparison of the nugget quality parameter and a nugget quality threshold in the relational database.

[0037] The welding quality control method provided by the embodiment of the present application establishes a relational database based on welding process and welding quality, adjusts welding process at each stage based on data in the relational database and real-time monitoring data before, during and after welding. Specifically, a pre-pressing value before welding is adjusted based on comparison of a gap parameter monitored in real time before welding and a gap threshold, so as to ensure that the gap between the plates meets the welding quality requirement; each welding parameter during welding is adjusted based on comparison of a nugget expansion volume monitored in real time during welding and a nugget expansion threshold, so as to ensure that the welding quality requirement is met; and whether to adjust a post-welding treatment parameter is determined based on comparison of a nugget quality parameter monitored in real time after welding and a nugget quality threshold, so as to ensure that the welding quality requirement is met.

[0038] The welding quality control system provided by the embodiment of the present application establishes a relational database based on welding process and welding quality, adjusts welding process at each stage based on data in the relational database and real-time monitoring data before, during and after welding. Specifically, a pre-pressing value before welding is adjusted based on comparison of a gap parameter monitored in real time before welding and a gap threshold, so as to ensure that the gap between the plates meets the welding quality requirement; each welding parameter during welding is adjusted based on comparison of a nugget expansion volume monitored in real time during welding and a nugget expansion threshold, so as to ensure that the welding quality requirement is met; and whether to adjust a post-welding treatment parameter is determined based on comparison of a nugget quality parameter monitored in real time after welding and a nugget quality threshold, so as to ensure that the welding quality requirement is met. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0040] Figure 1 is a flowchart of the welding quality control method provided by the present application;

[0041] Figure 2 is a structural schematic diagram of the welding quality control system provided by the present application;

[0042] Figure 3 is a schematic diagram of the principle of measuring the gap between two pieces to be welded by using a laser;

[0043] Figure 4 is a structural schematic diagram of a photosensitive element provided by the present application. DETAILED DESCRIPTION

[0044] The embodiments of the present application will be further described below in conjunction with the drawings and examples. The following examples are used to illustrate the present application, but cannot be used to limit the scope of the present application.

[0045] In the description of the embodiments of the present application, it should be noted that the terms “center”, “longitudinal”, “transverse”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer” and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the embodiments of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms “first”, “second”, “third” are only for descriptive purposes, and cannot be understood as indicating or implying relative importance.

[0046] In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms “connected” and “connected” should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0047] In the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature is “on” or “under” the second feature, which can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature can be directly above or obliquely above the second feature, or it can only mean that the horizontal height of the first feature is higher than that of the second feature. The first feature can be directly below or obliquely below the second feature, or it can only mean that the horizontal height of the first feature is less than that of the second feature.

[0048] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0049] The following will be described in conjunction with Figures 1-4 The welding quality control method of the present application is described, comprising the following steps:

[0050] S100, a relationship database of welding process and welding quality is established.

[0051] S200, the gap parameter between at least two pieces to be welded before welding is obtained, and based on the comparison of the gap parameter and the gap threshold value in the relationship database, the pre-pressing value before welding is adjusted.

[0052] S300, the expansion volume parameter of the nugget at the welding point during welding is obtained, and based on the comparison of the expansion volume parameter and the nugget expansion threshold value in the relationship database, the welding parameters during welding are adjusted.

[0053] S400, the nugget quality parameter of the nugget at the welding point after welding is obtained, and based on the comparison of the nugget quality parameter and the nugget quality threshold value in the relationship database, the post-processing parameters after welding are adjusted.

[0054] In the present embodiment, the relationship database is established based on the welding process and the welding quality, and according to the data in the relationship database, the welding process in each stage is adjusted based on the real-time monitoring data before, during and after welding. Specifically, according to the comparison of the gap parameter monitored in real time before welding and the gap threshold value, the pre-pressing value before welding is adjusted, so as to ensure that the gap between the plates meets the welding quality requirement; according to the comparison of the nugget expansion volume monitored in real time during welding and the nugget expansion threshold value, each welding parameter during welding is adjusted to ensure that the welding quality requirement is met; according to the comparison of the nugget quality parameter monitored in real time after welding and the nugget quality threshold value, it is judged whether to adjust the post-processing parameter to ensure that the welding quality requirement is met.

[0055] Wherein, after each welding, the pre-welding gap parameter corresponding pre-pressure value, the welding parameter corresponding to the expansion volume threshold of the nugget in the welding and the post-welding nugget quality corresponding to the post-processing parameter are all introduced into the established relational database, which are used as the parameters for comparison to adjust the welding process in the subsequent welding process.

[0056] Before welding, the gap value between the to-be-welded pieces can be adjusted according to the size of the pre-pressure value. The gap value between the to-be-welded pieces has a crucial influence on the external spatter and internal nugget quality of spot welding. Too large gap value can lead to appearance quality problems such as spot welding spatter and deformation, and internal nugget quality problems such as substandard nugget diameter or excessive defects. By adjusting the gap value of the to-be-welded pieces, the spot welding quality can be improved. When the pre-pressure value increases, the gap value between the at least two to-be-welded pieces can be reduced; when the pre-pressure value decreases, the gap value between the at least two to-be-welded pieces can be increased.

[0057] During welding, the welding parameters will affect the quality of the nugget, especially the expansion volume parameter of the nugget. Based on the expansion volume parameter of the nugget, it is determined whether the welding parameters need to be adjusted during the welding process. Specifically, the adjusted welding parameters include welding current, welding pressure, electrode pressure, welding time, cooling time, holding time and pulse number.

[0058] After welding, it is determined whether post-processing is needed and the specific way of post-processing based on the shape after welding.

[0059] In the embodiment, the step of establishing the relational database of the welding process and the welding quality specifically includes:

[0060] Establishing the relational database of the pre-welding pre-pressure, gap threshold and welding quality, establishing the relational database of the welding parameter, nugget expansion threshold and welding quality in the welding, and establishing the relational database of the post-processing parameter, nugget quality threshold and welding quality after welding.

[0061] It can be understood that the relational database includes the pre-welding relational database formed by the pre-pressure-gap threshold-welding quality, the welding-in relational database formed by the welding parameter-nugget expansion threshold-welding quality, and the post-welding relational database formed by the post-processing parameter-nugget quality threshold-welding quality.

[0062] The pre-pressure value is correlated with the gap value. When the pre-pressure value increases, the gap value between the at least two pieces to be welded decreases. When the pre-pressure value decreases, the gap value between the at least two pieces to be welded increases. For example, when the real-time monitored gap parameter is 50 mm (millimeter) and the gap threshold value is 30 mm, it indicates that the gap between the pieces to be welded is too large, and the gap between the pieces to be welded needs to be adjusted in time to ensure the subsequent welding quality. At this time, the pre-pressure before welding is increased to compress the gap between the pieces to be welded by making the at least two pieces to be welded have a greater pressure, so that the gap is reduced. When the real-time monitored gap parameter is less than or equal to 30 mm, the subsequent steps are performed at the current pre-pressure value.

[0063] As shown in Figure 3 and Figure 4 , the step of acquiring the gap parameter between the at least two pieces to be welded before welding specifically comprises:

[0064] The laser is emitted to the at least two pieces to be welded at the first position, and the laser is reflected on the surface of the at least two pieces to be welded to form at least two reflected light rays. The at least two reflected light rays are received by the photosensitive element at the second position, and the at least two reflected light rays correspondingly form at least two photosensitive positions on the photosensitive element. The gap value between the at least two pieces to be welded is calculated based on the interval between the at least two photosensitive positions.

[0065] For two pieces to be welded, the first piece to be welded 310 can be placed on the workbench first, and then the laser is emitted by the laser emitting unit 330. After the laser is reflected on the surface of the first piece to be welded 310, the reflected light ray is received at the first photosensitive position 350 of the photosensitive element 340. At this time, the point position of the first photosensitive position 350 is marked. Then the second piece to be welded 320 is placed on the surface of the first piece to be welded 310, and the second piece to be welded 320 and the first piece to be welded 310 are attached to each other at a set pre-pressure value. Then the laser is emitted by the laser emitting unit 330. After the laser is reflected on the surface of the second piece to be welded 320, the reflected light ray is received at the second photosensitive position 360 of the photosensitive element 340. At this time, the point position of the second photosensitive position 360 is marked. The gap value between the first piece to be welded 310 and the second piece to be welded 320 is calculated based on the interval between the first photosensitive position 350 and the second photosensitive position 360 and the reflection angle of the light ray. If the gap value is greater than the gap threshold value, the pre-pressure value is increased and the above measurement is performed again until the gap value meets the gap threshold value.

[0066] If the two to-be-welded parts are transparent, the laser can pass through the to-be-welded parts. At this time, the first to-be-welded part 310 is placed on the workbench, and the second to-be-welded part 320 is directly placed on the first to-be-welded part 310, and the second to-be-welded part 320 is attached to the first to-be-welded part 310 at a set pre-pressing force value. The laser can be emitted by the laser emitting unit 330, and after the laser is reflected on the surface of the first to-be-welded part 310, the reflected light is received at the first light sensing position 350 of the photosensitive element 340, and the laser passes through the first to-be-welded part 310 and is reflected at the position of the second to-be-welded part 320. After the laser is reflected on the surface of the second to-be-welded part 320, the reflected light is received at the second light sensing position 360 of the photosensitive element 340, the point position of the first light sensing position 350 and the point position of the second light sensing position 360 are recorded, and based on the distance between the first light sensing position 350 and the second light sensing position 360, and through the calculation of the light reflection angle, the gap value between the first to-be-welded part 310 and the second to-be-welded part 320 is calculated. If the gap value is greater than the gap threshold value, the pre-pressing force value is increased and the above measurement is performed again until the gap value meets the gap threshold value.

[0067] In the embodiment, based on the comparison of the gap parameter and the gap threshold value in the relational database, the step of adjusting the pre-pressing force value before welding specifically includes:

[0068] If the value of the gap parameter is less than or equal to the gap threshold value in the relational database, the pre-pressing force value before welding does not need to be adjusted.

[0069] If the value of the gap parameter is greater than the gap threshold value in the relational database, the pre-pressing force value before welding is increased.

[0070] Based on the value of the gap parameter, it is judged whether the pre-pressing force value before welding needs to be adjusted. When the pre-pressing force value is increased, the gap value between the at least two to-be-welded parts can be reduced. When the pre-pressing force value is reduced, the gap value between the at least two to-be-welded parts can be increased.

[0071] In one embodiment, when the real-time monitored gap parameter is 80 mm and the gap threshold value is 40 mm, it is indicated that the gap between the to-be-welded parts is too large at this time, and the gap between the to-be-welded parts needs to be adjusted in time to ensure the subsequent welding quality. At this time, the pre-pressing force before welding is increased to make the at least two to-be-welded parts have greater pressure to compress the gap between the to-be-welded parts, so that the gap is reduced. When the real-time monitored gap parameter is less than or equal to 40 mm, the subsequent steps are performed at the current pre-pressing force value.

[0072] In the embodiment, the step of obtaining the expansion volume parameter of the nugget at the welding point during welding specifically includes:

[0073] An expansion displacement sensor is added to the welding end of the welding mechanism, and the expansion volume value of the nugget is detected by the expansion displacement sensor.

[0074] Specifically, the expansion displacement sensor is added to the welding gun to monitor the expansion volume value of the fusion in real time. The detected expansion volume value directly reflects the expansion volume parameter of the fusion. Based on real-time monitoring, the data monitored by the expansion displacement sensor is fed back to the terminal in real time. The terminal compares the fed back expansion volume value with the nugget expansion threshold value in the relational database in the terminal, and synchronously feeds back the result after comparison and judgment to make an instruction on whether to adjust the welding parameters.

[0075] In this embodiment, based on the comparison of the expansion volume parameter and the nugget expansion threshold value in the relational database, the step of adjusting the welding parameters in the welding process specifically includes:

[0076] If the expansion volume parameter is within the range of the nugget expansion threshold value in the relational database, the welding parameters do not need to be adjusted.

[0077] If the expansion volume parameter is outside the range of the nugget expansion threshold value in the relational database, at least one of the welding current, the welding pressure, the electrode pressure, the welding time, the cooling time, the holding time and the pulse number is adjusted based on the relational database.

[0078] It can be understood that the welding parameters at least include at least one of the welding current, the welding pressure, the electrode pressure, the welding time, the cooling time, the holding time and the pulse number. In the welding process, whether the welding current, the welding pressure, the electrode pressure, the welding time, the cooling time, the holding time and the pulse number need to be adjusted is determined based on the real-time detected expansion volume parameter. For example, based on the change of the expansion volume parameter, the welding current can be increased, the welding pressure can be increased, the electrode pressure can be increased, the welding time can be prolonged, the cooling time can be prolonged, the holding time can be prolonged, and the pulse number can be increased.

[0079] In one embodiment, the pre-pressure can be set to 3kN (kilo Newton), the spot welding current can be set to 9KA (kilo Ampere), the welding time can be set to 180ms (millisecond), the cooling time can be set to 30ms, the pulse number can be set to 2, the holding time can be set to 600ms, and the electrode pressure can be set to 5.6kN.

[0080] In this embodiment, the step of obtaining the nugget quality parameter of the nugget at the welding spot after the welding is completed specifically includes:

[0081] The X-axis direction and the Y-axis direction of each welding spot are scanned by using a laser ranging device to form a rectangular scanning area, height ranging is performed on all detection points in the rectangular scanning area, and a three-dimensional profile is generated in cooperation with the values of the X-axis direction and the Y-axis direction, at least one parameter of a crater depth and a profile diameter at the nugget is calculated based on the three-dimensional profile.

[0082] After scanning each welding spot along the X-axis direction and the Y-axis direction, a rectangular scanning area of the welding spot on a horizontal plane can be generated, height ranging is performed in the rectangular scanning area, that is, scanning is performed along the Z-axis, and a three-dimensional profile at the welding spot is generated based on coordinate points of the X-axis, the Y-axis and the Z-axis. At least one parameter of a crater depth and a profile diameter at the nugget can be directly calculated based on the obtained three-dimensional profile. The quality of the nugget is judged based on at least one parameter of the crater depth and the profile diameter.

[0083] In the embodiment, the step of obtaining the nugget quality parameter of the nugget at the welding spot after welding is completed further includes:

[0084] Ultrasonic scanning is performed along the welding spot area by using an ultrasonic scanning device, and at least one parameter of a nugget diameter and a quality defect at the nugget is calculated based on the result of the ultrasonic scanning.

[0085] The position of the nugget of the welding spot is directly displayed by using ultrasonic scanning, and at least one parameter of a nugget diameter and a quality defect is calculated, so that the quality of the nugget is judged based on at least one parameter of the nugget diameter and the quality defect.

[0086] In the embodiment, the quality of the nugget is reflected based on the generated three-dimensional profile on one hand, and the quality of the nugget is reflected based on the result of the ultrasonic scanning on the other hand, and the quality of the nugget is reflected from two aspects together, so as to facilitate subsequent judgment.

[0087] In the embodiment, the step of adjusting the post-welding processing parameter based on the comparison between the nugget quality parameter and the nugget quality threshold value in the relational database specifically includes:

[0088] If the nugget quality parameter is located in the range of the nugget quality threshold value in the relational database, post-welding processing is not required.

[0089] If the nugget quality parameter is located outside the range of the nugget quality threshold value in the relational database, post-welding processing is performed on the welding position.

[0090] The post-welding processing at least includes processes such as grinding and repair welding. Post-welding processing based on the judgment of the quality of the nugget can optimize subsequent processes and shorten the time of the entire process.

[0091] The welding system provided by the present application is described below, and the welding system described below can be correspondingly referred to the welding method described above.

[0092] As Figure 2 shown, the embodiment provides a welding quality control system, comprising a database establishing unit, a first parameter acquiring unit, a first adjusting unit, a second parameter acquiring unit, a second adjusting unit, a third parameter acquiring unit and a third adjusting unit. The database establishing unit is used to establish a relationship database of welding process and welding quality. The first parameter acquiring unit is electrically connected with the database establishing unit, used to acquire the gap parameter between at least two pieces of workpieces before welding, and compare the gap parameter with the gap threshold value in the relationship database. The first adjusting unit is electrically connected with the first parameter acquiring unit, used to adjust the pre-pressure value before welding based on the comparison of the gap parameter and the gap threshold value in the relationship database. The second parameter acquiring unit is electrically connected with the database establishing unit, used to acquire the expansion volume parameter of the nugget at the welding spot during welding, and compare the expansion volume parameter with the nugget expansion threshold value in the relationship database. The second adjusting unit is electrically connected with the second parameter acquiring unit, used to adjust the welding parameter during welding based on the comparison of the expansion volume parameter and the nugget expansion threshold value in the relationship database. The third parameter acquiring unit is electrically connected with the database establishing unit, used to acquire the nugget quality parameter of the nugget at the welding spot after welding, and compare the nugget quality parameter with the nugget quality threshold value in the relationship database. The third adjusting unit is electrically connected with the third parameter acquiring unit, used to adjust the post-processing parameter after welding based on the comparison of the nugget quality parameter and the nugget quality threshold value in the relationship database.

[0093] In the embodiment, the relationship database is established based on the welding process and the welding quality, and then the welding process in each stage is adjusted based on the real-time monitoring data before, during and after welding according to the data in the relationship database. Specifically, the pre-pressure value before welding is adjusted according to the comparison of the gap parameter monitored in real time before welding and the gap threshold value, so as to ensure that the gap between the plates meets the welding quality requirement; each welding parameter during welding is adjusted according to the comparison of the nugget expansion volume monitored in real time during welding and the nugget expansion threshold value, so as to ensure that the welding quality requirement is met; whether to adjust the post-processing parameter is judged according to the comparison of the nugget quality parameter monitored in real time after welding and the nugget quality threshold value, so as to ensure that the welding quality requirement is met.

[0094] Among them, the welding quality control system can further comprise a terminal, the database establishing unit can upload the relationship database to the terminal, and the first parameter acquiring unit, the second parameter acquiring unit and the third parameter acquiring unit can upload the acquired parameters to the terminal, and after comparison in the terminal, send the adjustment signal to the first adjusting unit, the second adjusting unit and the third adjusting unit, so as to facilitate subsequent adjustment measures.

[0095] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of weld quality control, characterized by, The method comprises the following steps: establishing a welding process and welding quality relationship database, the relationship database comprising a pre-welding relationship database formed by pre-pressure-gap threshold-welding quality, a welding parameter-molten core expansion threshold-welding quality relationship database formed by welding parameters, and a post-welding relationship database formed by post-processing parameters-molten core quality threshold-welding quality; acquiring a gap parameter between at least two pieces to be welded before welding, and adjusting the pre-welding pre-pressure value based on a comparison between the gap parameter and the gap threshold in the relationship database; acquiring a molten core expansion volume parameter of the molten core at the welding spot during welding, and adjusting the welding parameter during welding based on a comparison between the expansion volume parameter and the molten core expansion threshold in the relationship database; acquiring a molten core quality parameter of the molten core at the welding spot after welding is completed, and adjusting the post-welding post-processing parameter based on a comparison between the molten core quality parameter and the molten core quality threshold in the relationship database, the molten core quality parameter being calculated based on a three-dimensional profile of the welding spot and an ultrasonic scanning result of the molten core of the welding spot.

2. The weld quality control method of claim 1, wherein, The step of acquiring the gap parameter between at least two pieces to be welded before welding specifically comprises: emitting laser light at the at least two pieces to be welded at a first position, the laser light being reflected on the surfaces of the at least two pieces to be welded and forming at least two reflected light beams, and receiving the at least two reflected light beams at a second position by using a photosensitive element, the at least two reflected light beams corresponding to form at least two photosensitive positions on the photosensitive element, and calculating the gap value between the at least two pieces to be welded based on the distance between the at least two photosensitive positions.

3. The weld quality control method of claim 2, wherein, The step of adjusting the pre-welding pre-pressure value based on a comparison between the gap parameter and the gap threshold in the relationship database specifically comprises: if the value of the gap parameter is less than or equal to the gap threshold in the relationship database, the pre-welding pre-pressure value does not need to be adjusted; if the value of the gap parameter is greater than the gap threshold in the relationship database, the pre-welding pre-pressure value is increased.

4. The weld quality control method of claim 1, wherein, The step of acquiring the molten core expansion volume parameter of the molten core at the welding spot during welding specifically comprises: adding an expansion displacement sensor to the welding end of a welding mechanism, and detecting the expansion volume value of the molten core by using the expansion displacement sensor.

5. The weld quality control method of claim 4, wherein, The step of adjusting the welding parameter during welding based on a comparison between the expansion volume parameter and the molten core expansion threshold in the relationship database specifically comprises: if the expansion volume parameter is within the range of the molten core expansion threshold in the relationship database, the welding parameter does not need to be adjusted; if the expansion volume parameter is outside the range of the molten core expansion threshold in the relationship database, at least one of the welding current, welding pressure, welding time, cooling time, holding time and pulse number is adjusted based on the relationship database.

6. The weld quality control method according to any one of claims 1-5, characterized in that, The step of acquiring the molten core quality parameter of the molten core at the welding spot after welding is completed specifically comprises: The X-axis direction and the Y-axis direction of each welding spot are scanned by using a laser ranging device to form a rectangular scanning area, height ranging of all detection points in the rectangular scanning area is performed, and a three-dimensional profile is generated in cooperation with the values of the X-axis direction and the Y-axis direction. At least one parameter of a crater depth and a profile diameter at the nugget is calculated based on the three-dimensional profile.

7. The weld quality control method of claim 6, wherein, The step of obtaining the nugget quality parameter of the nugget at the welding spot after welding is completed further includes: An ultrasonic scanning device is used to perform ultrasonic scanning along the welding spot area, and at least one parameter of a nugget diameter and a quality defect at the nugget is calculated based on the result of the ultrasonic scanning.

8. The weld quality control method of claim 7, wherein, The step of adjusting the post-welding processing parameter based on the comparison of the nugget quality parameter and the nugget quality threshold in the relational database specifically includes: If the nugget quality parameter is within the range of the nugget quality threshold in the relational database, no post-processing is required; If the nugget quality parameter is outside the range of the nugget quality threshold in the relational database, post-processing is performed on the welding site.

9. A welding quality control system characterized by, It includes: A database establishing unit is configured to establish a welding process and welding quality relational database, which includes a pre-welding relational database formed by a pre-pressure-gap threshold-welding quality, a welding process relational database formed by a welding parameter-nugget expansion threshold-welding quality, and a post-welding relational database formed by a post-processing parameter-nugget quality threshold-welding quality; A first parameter obtaining unit is electrically connected to the database establishing unit and configured to obtain a gap parameter between at least two pieces of workpieces before welding, and compare the gap parameter with a gap threshold in the relational database; A first adjusting unit is electrically connected to the first parameter obtaining unit and configured to adjust a pre-welding pre-pressure value based on the comparison of the gap parameter and the gap threshold in the relational database; A second parameter obtaining unit is electrically connected to the database establishing unit and configured to obtain an expansion volume parameter of a nugget at a welding spot during welding, and compare the expansion volume parameter with a nugget expansion threshold in the relational database; A second adjusting unit is electrically connected to the second parameter obtaining unit and configured to adjust a welding parameter during welding based on the comparison of the expansion volume parameter and the nugget expansion threshold in the relational database; A third parameter obtaining unit is electrically connected to the database establishing unit and configured to obtain a nugget quality parameter of a nugget at a welding spot after welding is completed, and compare the nugget quality parameter with a nugget quality threshold in the relational database. The nugget quality parameter is calculated based on a three-dimensional profile at the welding spot and an ultrasonic scanning result of the nugget at the welding spot. A third adjusting unit is electrically connected to the third parameter obtaining unit and configured to adjust a post-welding processing parameter based on the comparison of the nugget quality parameter and the nugget quality threshold in the relational database.

Images