A method of weld cleaning

Abstract

The present application relates to the technical field of weld cleaning, and particularly relates to a weld cleaning method, which comprises the following steps: determining whether a switch mode power supply is switched from a constant power control mode to a control mode for a weld cleaning device; determining a delay time length when the constant power control mode or the constant current control mode is switched to the constant voltage control mode; marking weld areas affected by each control mode as corresponding cleaning areas; determining whether to adjust the brush rotating speed of the brush in the corresponding cleaning area, or to adjust the contact area of the brush at the position of the jumping moment, and determining the advancing rate of the electrolyte; actually cleaning the weld to be cleaned; detecting the flatness of the weld surface until the flatness of the weld surface meets the requirements. The present application increases the weld cleaning efficiency and the stability of the cleaning process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of weld cleaning, in particular to a weld cleaning method. BACKGROUND

[0002] In the prior art, the weld is cleaned by a device for cleaning, polishing, marking and passivating the weld, all functions are realized by current, brush, brush, surface cleaner and chemicals, the cleaner or the chemical is applied to the material through the conveyor belt, and a reaction is generated through the current, so as to achieve the purpose of cleaning impurities on the weld.

[0003] Chinese patent publication No. CN105750714A discloses a steel plate submerged arc welding process, which comprises the following steps:

[0004] 1) Preparation before welding

[0005] 1.1) Prepare the welding wire and flux, remove dirt, oil, rust and other substances from the welding wire, and regularly coil the welding wire in the welding wire disc. The flux should be dried in advance (baked at 250°C for 1-2 hours), and other impurities should not be mixed; the workpiece welding opening should be degreased, decontaminated and dehydrated;

[0006] 1.2) Turn on the three-phase power switch of the control box;

[0007] 1.3) Check the welding equipment. Under no load conditions, the forward and reverse rotation of the positioner, the normality of the welding wire upward and downward, the normality of the rotation speed of the positioner observed by rotating the welding speed regulator; loosen the welding wire feeding wheel, test the action of the start and stop buttons, and rotate the arc voltage regulator to observe the rotation speed of the wire feeding wheel;

[0008] 1.4) Clean the electrode tip, adjust the pressure of the electrode tip on the welding wire to ensure good conductivity, and ensure smooth wire feeding;

[0009] 1.5) Preliminarily determine the welding specification according to the thickness of the welding piece, make a test piece of the same thickness before welding, adjust the welding specification according to the penetration of the test piece (X-ray perspective or cutting of the weld, according to the fusion of the cross-section of the weld) and surface forming, and determine the best welding specification after repeated testing;

[0010] 1.6) Align the electrode tip with the weld, and finely adjust the transverse adjustment handwheel of the welding machine to align the welding wire with the weld;

[0011] 1.7) Press the welding wire downward button to approach the welding wire to the workpiece, and the distance between the welding gun head and the workpiece should not be less than 15mm, and the length of the welding wire should not be less than 30mm;

[0012] 1.8) Check whether the positions of the positioner rotation switch and the circuit breaker switch are correct, and adjust the rotation speed;

[0013] 1.9) open the flux leakage head gate, so that the flux buried welding wire, the flux layer height is generally 30-50mm;

[0014] 2), welding work

[0015] 2.1) press the start button, at this time the welding wire is pulled up, then the welding wire is automatically changed to downward and the workpiece is contacted and rubbed to cause the arc to ensure the normal combustion of the arc, and the welding work is normally carried out;

[0016] 2.2) the current and voltage must be observed at any time during the welding process, and the relevant adjuster (or button) is adjusted in time; make it meet the required welding specification, when the network voltage is found to be too low, the welding work should be stopped immediately to avoid seriously affecting the penetration quality, and then the work is carried out after the network voltage returns to normal; when using 4mm welding wire, the welding seam width is required to be >10mm, the welding speed is ≈15m / h when welding groove, the voltage is ≈24V, the current is ≈300A, when approaching the surface, the voltage is >27V, the current is ≈450A; when welding the ball valve, generally use low voltage and small current when welding the first layer, because there is no good cooling, it is afraid that the temperature is too high to damage the inner part and the inner stress is large; when welding the second layer and later, the water cooling must be carried out, the voltage and current can be increased, and it is good to easily clean the welding slag;

[0017] 2.3) the degree of penetration and the surface forming of the weld should also be observed at any time during the welding process, the degree of penetration can be judged by observing the red heat degree of the back side of the workpiece, and the surface forming can be observed by removing the welding slag after welding a small section, if the degree of penetration and the surface forming are not good, adjust the specification in time to save the loss;

[0018] 2.4) attention should be paid to whether the welding wire is aligned with the center of the weld to prevent welding deviation, the observation position of the welder should be the same as the position when adjusting the welding wire during arc striking to reduce visual error, when welding the inner weld of small diameter cylinder, the direction of the arc can be judged according to the red heat of the back of the weld to adjust;

[0019] 2.5) the amount of flux in the flux hopper should be observed frequently, and added in time, when the flux flows down not smoothly, the channel should be dredged in time to remove the large obstacles.

[0020] It can be seen that the steel plate submerged arc welding process has the problems of insufficient current flowing through the required current due to insufficient driving voltage during electrolytic cleaning, resulting in decreased cleaning stability, excessive current when dynamically reducing the resistance, resulting in electrolyte being burned out, and uneven distribution of contact resistance when the brush cleans the weld, resulting in decreased cleaning efficiency. SUMMARY

[0021] To this end, the present application provides a welding seam cleaning method to overcome the problems in the prior art that the required current is insufficient when high resistance is generated due to insufficient driving voltage in the electrolytic cleaning process, the electrolyte is burned out due to excessive current when the dynamic resistance is reduced, and the cleaning efficiency is reduced due to uneven distribution of contact resistance when the brush cleans the welding seam.

[0022] To achieve the above-mentioned object, the present application provides a welding seam cleaning method, comprising:

[0023] Step S1, sequentially immersing the brush on the welding seam cleaning device into the electrolyte and placing it on the welding seam to be cleaned;

[0024] Step S2, determining whether the switch mode power supply is switched from the constant power control mode to the control mode for the welding seam cleaning device according to the contact resistance of the brush, the control mode further comprising a constant current control mode and a constant voltage control mode;

[0025] Step S3, determining the delay time length switched from the constant power control mode or the constant current control mode to the constant voltage control mode according to the thickness of impurities on the welding seam to be cleaned, and pre-cleaning the welding seam to be cleaned;

[0026] Step S4, marking the welding seam area acted by each control mode in the pre-cleaning process as the corresponding cleaning area respectively;

[0027] Step S5, determining whether to adjust the brush rotation speed of the brush in the corresponding cleaning area based on the fluctuation amplitude of the output voltage or the output current of the welding seam cleaning device in the corresponding cleaning area,

[0028] or, adjusting the contact area of the position of the brush at the jumping time when the control mode is triggered according to the resistance at the jumping time, and determining the advancing rate of the electrolyte according to the temperature change amount in the adjusted contact area;

[0029] Step S6, starting the brush of the welding seam cleaning device to actually clean the welding seam to be cleaned according to the brush rotation speed / according to the contact area and the electrolyte flow rate;

[0030] Step S7, detecting the flatness of the welding seam surface to determine whether to repeat the steps S5 to S7 until the flatness of the welding seam surface meets the requirements.

[0031] Further, the starting condition of the constant power control mode is that the contact resistance is within a preset resistance threshold,

[0032] wherein the output power of the switch mode power supply in the welding seam cleaning device is proportional to the contact resistance, and the contact resistance is the ratio of the output voltage to the output current.

[0033] Further, the starting condition of the constant voltage control mode is that the output voltage of the switch mode power supply is greater than or equal to a preset voltage, and the output current is less than a preset current.

[0034] Further, the starting condition of the constant current control mode is that the output current of the switch mode power supply is greater than or equal to the preset current, and the output voltage is less than the preset voltage.

[0035] Further, the process of the step S3 comprises:

[0036] acquiring the maximum impurity thickness on the weld to be cleaned;

[0037] when the maximum impurity thickness exceeds a preset thickness, determining that the wetting degree of the electrolyte does not meet the requirements, and increasing the delay time length for switching from the constant power control mode or the constant current control mode to the constant voltage control mode,

[0038] wherein the delay time length is positively correlated with the maximum impurity thickness.

[0039] Further, the process of the step S5 comprises:

[0040] respectively acquiring the cleaning area of the weld to be cleaned when the switch mode power supply is in the constant power control mode, the constant current control mode and the constant voltage control mode.

[0041] in the area of the constant power control mode, the brush speed remains unchanged;

[0042] in the area of the constant current control mode, if the fluctuation amplitude of the output voltage is greater than a preset second voltage fluctuation amplitude, it is determined that the impurities in the electrolyte are dense, and the brush speed is reduced;

[0043] in the area of the constant voltage control mode, if the fluctuation amplitude of the output current is greater than a preset second current fluctuation amplitude, it is determined that the surface electrolytic reaction degree of the weld to be cleaned does not meet the requirements, and the brush speed is increased,

[0044] wherein the fluctuation amplitude of the output voltage is the absolute value of the difference between the maximum and minimum values of the output voltage in the area of the constant current control mode; the fluctuation amplitude of the output current is the absolute value of the difference between the maximum and minimum values of the output current in the area of the constant voltage control mode;

[0045] the brush speed in the constant current control mode is inversely proportional to the fluctuation amplitude of the output voltage; the brush speed in the constant voltage control mode is positively correlated with the fluctuation amplitude of the output current.

[0046] Further, the step S5 includes:

[0047] If the fluctuation amplitude of the output voltage is greater than or equal to a preset first voltage fluctuation amplitude and less than or equal to a preset second voltage fluctuation amplitude, or the fluctuation amplitude of the output current is greater than or equal to a preset first current fluctuation amplitude and less than or equal to a preset second current fluctuation amplitude, it is preliminarily determined that the impurity treatment uniformity does not meet the requirements, and the jump time resistance when the adaptive control mode is triggered is obtained.

[0048] If the jump time resistance is greater than or equal to a preset jump time resistance, it is secondarily determined that the impurity treatment uniformity does not meet the requirements, and the contact area is increased.

[0049] The increase amplitude of the contact area is proportional to the jump time resistance, respectively.

[0050] Further, the step S5 includes:

[0051] The temperature change amount per unit time in the increased contact area of the brush is obtained.

[0052] The electrolyte pushing rate increases with the increase of the temperature change amount,

[0053] The temperature change amount is the difference between the temperature at the end of the unit time and the temperature at the beginning of the unit time.

[0054] Further, in the step S7, if the flatness is greater than or equal to a preset flatness, it is determined that the weld cleaning is not completed.

[0055] If the flatness is less than the preset flatness, it is determined that the weld cleaning is completed.

[0056] The flatness is the average impurity thickness of each position on the weld to be cleaned.

[0057] Further, the usage frequency of the switch mode power supply is not less than 100 kHz, and the output ripple peak-peak value of the output voltage is not higher than 2000 mV.

[0058] Compared with the prior art, the method has the beneficial effects that the method uses a high-frequency switch mode power supply to effectively reduce the ripple of the output voltage, thereby improving the stability of the electrolyte, and the output voltage and the output current are individually regulated by adjusting the adaptive control mode, the output current is too much when the resistance decreases due to the dynamic change of the contact resistance during electrolysis, which in turn causes the electrolyte to overheat and be burned out, or the output voltage is insufficient to electrolyze impurities due to the increase of the resistance, which in turn causes incomplete electrolysis, the power is kept constant by adjusting the control mode, the electrolysis stability is increased, the current density in the brush is kept constant by keeping the output current constant, the uniformity of impurity electrolysis is increased, the output voltage is kept constant, and the current up to the maximum current is established according to the basic resistance, and the electrolysis efficiency is improved; during the contact electrolysis of the brush and the impurities, the electrolysis is intense, which causes the electrolysis reaction temperature to increase, and the wetting degree of the brush decreases too fast, the lower the wetting degree of the brush, the greater the resistance in the output loop of the electrolysis device, and in turn the current is increased, which causes the contact resistance of the switching adaptive control mode to produce an error, and in turn the high current damages the welding part, the accuracy of electrolysis is increased by adjusting the delay time, the brush speed and the contact area of the brush are adjusted according to the electrolysis performance of different control modes, the cleaning effect is reduced in the place with uneven contact resistance due to the constant current density of the brush under the constant current control, or the impurities in the electrolyte accumulate due to the intense electrochemical reaction caused by the large current required by the impurities in the constant voltage control area, the cleaning efficiency, the cleaning stability and the uniformity are improved by adjusting the brush speed and the contact area of the brush.

[0059] Further, the method sets the preset resistance threshold, the preset voltage and the preset current, so that the adaptive control mode of the switch mode power supply changes with the required reaction conditions during electrolysis, thereby ensuring that the change of the contact resistance between the brush and the weld can be timely responded and adapted at different electrolysis stages, when the contact resistance is low, the method automatically switches to the constant power control mode to prevent the electrolyte from overheating due to excessive current, as the electrolysis process proceeds or the impurity composition or the contact resistance changes, the contact resistance gradually increases, and then the method switches to the constant current control mode to keep the current density of the brush constant, thereby improving the stability of electrolysis, when the required current is too large, the method switches to the constant voltage control mode to fully electrolyze the impurities, thereby improving the electrolysis effect.

[0060] Further, the method of the present application adjusts the brush rotation speed according to different regions. Due to uneven distribution of contact resistance in different regions, the same brush rotation speed cannot better achieve the cleaning of the weld. The electrolysis reaction degree is gentle in the constant power control mode region, and the electrolysis reaction degree is intense in the constant voltage control mode region. Impurities are generated in the electrolyte during the electrolysis process and are accumulated. By increasing the brush rotation speed, the electrolyte impurity accumulation is reduced. In the constant current control mode region, due to the uneven thickness of the impurities on the surface of the weld to be cleaned, the brush rotation speed needs to be reduced to ensure the uniformity of the electrolysis reaction, thereby improving the electrolysis effect.

[0061] Further, the method of the present application adjusts the contact area of the brush on the weld to be cleaned. During the switching of the adaptive control mode, the brush is still moving, which causes incomplete cleaning of the positions between different regions. By increasing the contact area, the uniformity of the electrolysis is improved, and the electrolysis effect is improved.

[0062] Further, the method of the present application adjusts the electrolyte flow rate. Due to the increase of the contact area, the temperature near the center of gravity in the connection area between the brush and the weld is increased, which further affects the physical properties of the welded part. By increasing the electrolyte flow rate to cool the connection position while preventing the electrolyte from overheating, the stability of the electrolysis is increased, and the electrolysis efficiency is increased.

[0063] Further, the method of the present application sets the use frequency of the switching mode power supply and the output ripple peak-to-peak value of the output voltage to avoid the electrolyte instability and brush damage caused by excessive voltage fluctuation, thereby improving the stability and safety of the cleaning process. BRIEF DESCRIPTION OF DRAWINGS

[0064] Figure 1 The overall flowchart of the weld cleaning method of the embodiment of the present application is shown in the figure.

[0065] Figure 2 The structure schematic diagram of the weld cleaning device of the weld cleaning method of the embodiment of the present application is shown in the figure.

[0066] Figure 3 The voltage-current schematic diagram of the control mode of the weld cleaning method of the embodiment of the present application is shown in the figure.

[0067] Figure 4 The flowchart of adjusting the brush rotation speed of the brush in the corresponding cleaning region of the weld cleaning method of the embodiment of the present application is shown in the figure.

[0068] BRIEF DESCRIPTION OF DRAWINGS: 1-handle, 2-electric telescopic rod, 3-electrolyte pump, 4-electrolyte container bottle, 5-weld to be cleaned, 6-brush, 7-welded part, 8-electric rotating table, 9-electrolyte delivery pipe DETAILED DESCRIPTION

[0069] In order to make the objects, technical schemes and advantages of the present application clearer, the following further describes the present application with reference to the embodiments; it should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0070] The preferred embodiments of the present application are described below with reference to the drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application and not to limit the protection scope of the present application.

[0071] It should be noted that, in the description of the present application, the terms indicating the direction or positional relationship of "upper", "lower", "left", "right", "inner", "outer" and the like are based on the direction or positional relationship shown in the drawings, which is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0072] In addition, it should also be noted that, in the description of the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two elements. Those skilled in the art can understand the specific meaning of the above terms in the present application according to the specific circumstances.

[0073] Please refer to Figure 1 , Figure 2 , Figure 3 and Figure 4 , which are respectively the overall flowchart of the welding seam cleaning method, the structure schematic diagram of the welding seam cleaning device, the voltage-current schematic diagram and the flowchart of adjusting the brush speed of the brush corresponding to the cleaning area. The welding seam cleaning method of the present application embodiment comprises:

[0074] Step S1, the brush on the welding seam cleaning equipment is sequentially immersed in the electrolyte and placed on the welding seam to be cleaned;

[0075] Step S2, determining whether the switch mode power supply is switched from the constant power control mode to the control mode for the welding seam cleaning equipment according to the contact resistance of the brush, the control mode further comprising a constant current control mode and a constant voltage control mode;

[0076] Step S3, determining the delay time length of switching from the constant power control mode or the constant current control mode to the constant voltage control mode according to the thickness of the impurities on the welding seam to be cleaned, and pre-cleaning the welding seam to be cleaned;

[0077] Step S4, marking the weld area of each control mode in the pre-cleaning process as the corresponding cleaning area respectively;

[0078] Step S5, determining whether to adjust the brush rotation speed of the brush in the corresponding cleaning area based on the fluctuation amplitude of the output voltage or output current of the weld cleaning device in the corresponding cleaning area,

[0079] Or, according to the contact area of the position of the brush at the jump moment when the control mode is triggered, and according to the temperature change amount in the adjusted contact area, determine the advancing rate of the electrolyte;

[0080] Step S6, starting the brush of the weld cleaning device to clean the weld to be cleaned according to the brush rotation speed / according to the contact area and the electrolyte flow rate;

[0081] Step S7, detecting the flatness of the weld surface to determine whether to repeat the steps S5 to S7 until the flatness of the weld surface meets the requirements.

[0082] Specifically, the switch mode power supply of the weld cleaning device is a high frequency power conversion device. The switch mode power supply is used to convert a voltage of one level into a voltage or current required by electrolysis through different forms of architecture. The control mode conversion method of the switch mode power supply is a prior art known to those skilled in the art, and therefore will not be described in detail here.

[0083] Specifically, the switch mode power supply in the weld cleaning device also serves as a main inverter to limit the output voltage and output current within + / -1.5%, with an efficiency of >83%.

[0084] Specifically, the impurities on the weld to be cleaned 5 include iron oxides, aluminum oxides, and nickel oxides.

[0085] Specifically, the weld cleaning device is provided with a handle 1, the handle 1 is connected with the brush 6 through an electric telescopic rod 2, and the electric telescopic rod 2 is connected with the brush 6 through an electric rotating table 8.

[0086] Specifically, the extrusion force of the brush 6 on the weld cleaning device and the weld to be cleaned 5 is adjusted through the telescopic adjustment of the electric telescopic rod, so as to adjust the contact area.

[0087] In the implementation, the method of the present application effectively reduces the ripple of the output voltage by using a high-frequency switch mode power supply, thereby improving the stability of the electrolyte, and the output voltage and the output current are individually regulated by adjusting the adaptive control mode. Since the dynamic change of the contact resistance during the electrolysis process causes the output current to be excessive when the resistance decreases, which in turn causes the electrolyte to overheat and be burned out, or the output voltage to be insufficient to electrolyze impurities when the resistance increases, which in turn causes incomplete electrolysis. By adjusting the control mode, the power is kept constant, which increases the stability of the electrolysis. By keeping the output current constant, the current density in the brush is kept constant, which increases the uniformity of the electrolysis of impurities. By keeping the output voltage constant, a current up to the maximum current is established based on the base resistance, which improves the efficiency of the electrolysis. Since the electrolysis is intense during the contact between the brush and the impurities, the temperature of the electrolysis reaction increases, and the wetness level of the brush decreases too quickly. The lower the wetness level of the brush, the greater the resistance in the output circuit of the electrolysis device, which in turn increases the current, causing the contact resistance of the adaptive control mode to produce an error, which in turn causes excessive current to damage the weldment. By adjusting the delay time, the accuracy of the electrolysis is improved. By adjusting the brush speed and the contact area of the brush according to the electrolysis performance of different control modes, the cleaning effect is reduced in areas with uneven contact resistance under constant current control, or impurities accumulate in the electrolyte due to the intense electrochemical reaction caused by the large current required by the impurities in the constant voltage control area. By adjusting the brush speed and the contact area of the brush, the cleaning efficiency, stability and uniformity are improved.

[0088] Specifically, the starting condition of the constant power control mode is that the contact resistance is within a preset resistance threshold,

[0089] wherein the output power of the switch mode power supply in the weld cleaning device is proportional to the contact resistance, and the contact resistance is the ratio of the output voltage to the output current.

[0090] Specifically, the starting condition of the constant voltage control mode is that the output voltage of the switch mode power supply is greater than or equal to a preset voltage, and the output current is less than a preset current.

[0091] Specifically, the starting condition of the constant current control mode is that the output current of the switch mode power supply is greater than or equal to the preset current, and the output voltage is less than the preset voltage.

[0092] Specifically, the contact resistance depends on the material of the weld, the chemical reaction and the conductivity of the electrolyte.

[0093] Specifically, the preset voltage is 36V, and the preset current is 95% of the rated current.

[0094] In the implementation, the method of the present application changes the adaptive control mode of the switch mode power supply according to the required reaction conditions in the electrolysis process by setting the preset resistance threshold, the preset voltage and the preset current, so as to ensure that the change of the contact resistance between the brush 6 and the weld joint can be timely responded and adapted in different electrolysis stages. When the contact resistance is low, the method automatically switches to the constant power control mode to prevent the electrolyte from overheating due to excessive current. As the electrolysis process proceeds or the impurity composition or the contact resistance changes, the contact resistance gradually increases, and then the method switches to the constant current control mode to keep the current density of the brush 6 constant, thereby improving the stability of the electrolysis. When the required current is too large, the method switches to the constant voltage control mode to fully electrolyze the impurities, thereby improving the electrolysis effect.

[0095] Specifically, the process of the step S3 includes:

[0096] acquiring the maximum impurity thickness on the weld joint 5 to be cleaned up;

[0097] when the maximum impurity thickness exceeds the preset thickness, determining that the wetting degree of the electrolyte does not meet the requirements, and increasing the delay time length for switching from the constant power control mode or the constant current control mode to the constant voltage control mode,

[0098] wherein the delay time length is positively correlated with the maximum impurity thickness.

[0099] Specifically, the impurity thickness is detected by ultrasonic waves, and the impurity thickness is half of the product of the propagation speed of ultrasonic waves in the impurities and the reflection time.

[0100] Specifically, the delay time length is adjusted by a time delay relay.

[0101] Specifically, the preset thickness generally has a value range of [2.2 mm, 2.4 mm].

[0102] Preferably, the preferred embodiment of the preset thickness is 2.3 mm.

[0103] In the implementation, the difference between the maximum impurity thickness and the preset thickness is within 0.1 mm, the delay time length is increased by 0.5 s, the difference between the maximum impurity thickness and the preset thickness exceeds 0.1 mm, and the delay time length is increased by 0.4 s for each 0.1 mm. For example, the maximum impurity thickness is 2.6 mm, the current delay time length is 0 s, and the delay time length is increased to 0 s+0.5 s+0.4 s×2=1.3 s.

[0104] Specifically, the process of the step S5 includes:

[0105] respectively acquiring the cleaning area of the weld joint 5 to be cleaned up when the switch mode power supply is in the constant power control mode, the constant current control mode and the constant voltage control mode.

[0106] The brush speed remains unchanged in the constant power control mode region;

[0107] In the constant current control mode region, if the fluctuation amplitude of the output voltage is greater than a preset second voltage fluctuation amplitude, it is determined that the impurities in the electrolyte are dense, and the brush speed is reduced;

[0108] In the constant voltage control mode region, if the fluctuation amplitude of the output current is greater than a preset second current fluctuation amplitude, it is determined that the surface electrolytic reaction degree of the weld 5 to be cleaned does not meet the requirements, and the brush speed is increased,

[0109] The fluctuation amplitude of the output voltage is the absolute value of the difference between the maximum and minimum values of the output voltage in the constant current control mode region; the fluctuation amplitude of the output current is the absolute value of the difference between the maximum and minimum values of the output current in the constant voltage control mode region;

[0110] The brush speed in the constant current control mode is inversely proportional to the fluctuation amplitude of the output voltage; the brush speed in the constant voltage control mode is proportional to the fluctuation amplitude of the output current.

[0111] Specifically, the preset second voltage fluctuation amplitude generally has a value range of [3.6V, 4.4V], and the preset second current fluctuation amplitude generally has a value range of [1.2A, 1.5A].

[0112] Preferably, the preferred embodiment of the preset voltage fluctuation amplitude is 4V, and the preferred embodiment of the preset current fluctuation amplitude is 1.3A.

[0113] In implementation, when the difference between the fluctuation amplitude of the output voltage and the preset second voltage fluctuation amplitude is within 1V, the brush speed is reduced to 0.9 times the original speed, and when the difference between the fluctuation amplitude of the output voltage and the preset second voltage fluctuation amplitude exceeds 1V, the brush speed is reduced by 0.2r / s for each 1V, for example, when the fluctuation amplitude of the output voltage is 6V and the current brush speed is 6r / s, the brush speed is reduced to 6r / s x 0.9 - 0.2r / s = 5.2r / s.

[0114] In implementation, when the difference between the fluctuation amplitude of the output current and the preset second current fluctuation amplitude is within 0.1A, the brush speed is increased by 0.5r / s, and when the difference between the fluctuation amplitude of the output current and the preset second current fluctuation amplitude exceeds 0.1A, the brush speed is increased by 0.4r / s for each 0.1A, for example, when the fluctuation amplitude of the output current is 1.5A and the current brush speed is 5r / s, the brush speed is increased to 5r / s + 0.5r / s + 0.4r / s = 5.9r / s.

[0115] Specifically, the rotation speed of the brush 6 in the corresponding cleaning area is realized by moving the brush 6 driven by the electric rotating table in the welding seam cleaning device.

[0116] In the implementation, the method of the present application adjusts the rotation speed of the brush according to different areas. Due to the uneven distribution of the contact resistance in different areas, the same rotation speed of the brush cannot better achieve the cleaning of the welding seam. The electrolysis reaction degree is gentle in the constant power control mode area, and the electrolysis reaction degree is intense in the constant voltage control mode area. Impurities are generated in the electrolysis process and accumulated. By increasing the rotation speed of the brush, the accumulation of electrolyte impurities is reduced. In the constant current control mode area, due to the uneven thickness of the impurities on the surface of the welding seam 5 to be cleaned, the rotation speed of the brush needs to be reduced to ensure the uniformity of the electrolysis reaction, thereby improving the electrolysis effect.

[0117] Specifically, the process of step S5 includes:

[0118] If the fluctuation amplitude of the output voltage is greater than or equal to the preset first voltage fluctuation amplitude and less than or equal to the preset second voltage fluctuation amplitude, or the fluctuation amplitude of the output current is greater than or equal to the preset first current fluctuation amplitude and less than or equal to the preset second current fluctuation amplitude, it is preliminarily determined that the impurity treatment uniformity does not meet the requirements, and the jump time resistance when the adaptive control mode is triggered is obtained.

[0119] If the jump time resistance is greater than or equal to the preset jump time resistance, it is secondly determined that the impurity treatment uniformity does not meet the requirements, and the contact area is increased.

[0120] The increase amplitude of the contact area is proportional to the jump time resistance, respectively.

[0121] Specifically, the preset first voltage fluctuation amplitude generally has a value range of [3V, 3.3V], and the preset first current fluctuation amplitude generally has a value range of [0.8A, 1.2A].

[0122] Preferably, the preferred embodiment of the preset voltage fluctuation amplitude is 3.2V, and the preferred embodiment of the preset current fluctuation amplitude is 1A.

[0123] Specifically, the contact area between the brush 6 and the welding seam 5 to be cleaned is increased by increasing the pressure of the brush 6.

[0124] Specifically, the preset jump time resistance generally has a value range of [75mΩ, 82mΩ].

[0125] Preferably, the preferred embodiment of the preset jump time resistance is 78mΩ.

[0126] In the implementation, when the difference between the jump time resistance and the preset jump time resistance is within 1 mΩ, the contact area is increased by 1.05 times, and when the difference between the jump time resistance and the preset jump time resistance exceeds 1 mΩ, the contact area is increased by 1 cm per 1 mΩ 2 For example, the jump time resistance is 80 mΩ, the contact area of the current brush 6 with the weld 5 to be cleaned is 5 cm 2 , and the contact area is increased to 5 cm 2 × 1.05 + 1 cm 2 = 6.25 cm 2 .

[0127] In the implementation, the method of the present application adjusts the contact area of the brush on the weld to be cleaned. During the process of switching the adaptive control mode, the brush is still moving, which causes incomplete cleaning of the positions between different areas. By increasing the contact area, the uniformity of electrolysis and the electrolysis effect are improved.

[0128] Specifically, the process of step S5 includes:

[0129] Obtaining the temperature change amount per unit time in the increased contact area of the brush;

[0130] The advancing rate of the electrolyte increases with the increase of the temperature change amount,

[0131] Wherein, the temperature change amount is the difference between the temperature at the end of the unit time and the temperature at the beginning of the unit time.

[0132] Specifically, the temperature in the increased contact area of the brush is detected by a temperature sensor on the brush corresponding to the center position of the electric rotating table.

[0133] Specifically, the brush 6 is connected with an electrolyte container bottle 4, and an electrolyte pump 3 for adjusting the advancing speed of the electrolyte is arranged between the electrolyte container bottle 4 and the brush.

[0134] Specifically, an electrolyte delivery pipe 9 is arranged between the brush 6 and the electrolyte pump 3, and an electrolyte delivery pipe 9 is arranged between the electrolyte pump 3 and the electrolyte container bottle 4.

[0135] In the implementation, the method of the present application adjusts the flow rate of the electrolyte. Due to the increase of the contact area, the temperature near the center of gravity position in the contact area of the brush and the weld is increased, which further affects the physical properties of the welded part. By increasing the flow rate of the electrolyte to cool the connection position while preventing overheating of the electrolyte, the stability of the electrolysis and the efficiency of the electrolysis are increased.

[0136] Specifically, in step S7, if the flatness is greater than or equal to the preset flatness, it is determined that the weld cleaning is not completed;

[0137] If the flatness is less than the preset flatness, it is determined that the weld cleaning is completed.

[0138] The flatness is the average impurity thickness of each position on the weld 5 to be cleaned.

[0139] Specifically, the preset flatness generally has a value range of (0mm, 0.05mm].

[0140] Preferably, the preferred embodiment of the preset flatness is 0.02mm.

[0141] Specifically, the usage frequency of the switch mode power supply is not less than 100kHz, and the output voltage has an output ripple peak-to-peak value not higher than 2000mV.

[0142] In implementation, the method of the present application sets the usage frequency of the switch mode power supply and the output ripple peak-to-peak value of the output voltage, thereby avoiding electrolyte instability and brush 6 damage caused by excessive voltage fluctuation, and achieving the improvement of stability and safety of the cleaning process.

[0143] So far, the technical solution of the present application has been described in combination with the preferred embodiments shown in the drawings, but those skilled in the art can easily understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the present application, and the technical solutions after these changes or replacements will all fall within the protection scope of the present application.

Claims

1. A method of weld cleaning, characterized by, The method comprises the following steps: S1, sequentially immersing the brush on the weld cleaning device into electrolyte and placing on the weld to be cleaned; S2, determining whether the switch mode power supply is switched from the constant power control mode to the control mode for the weld cleaning device according to the contact resistance of the brush, the control mode further comprising a constant current control mode and a constant voltage control mode; S3, determining the delay time period for switching from the constant power control mode or the constant current control mode to the constant voltage control mode according to the thickness of impurities on the weld to be cleaned, and pre-cleaning the weld to be cleaned; S4, marking the weld area subjected to each control mode in the pre-cleaning process as the corresponding cleaning area; S5, determining whether to adjust the brush rotation speed of the brush in the corresponding cleaning area based on the fluctuation amplitude of the output voltage or output current of the weld cleaning device in the corresponding cleaning area, or, determining the advancing rate of electrolyte according to the contact area of the brush at the jumping time when the control mode is triggered and the temperature change amount in the adjusted contact area; S6, starting the brush of the weld cleaning device to actually clean the weld to be cleaned according to the adjusted brush rotation speed / according to the contact area and the advancing rate of electrolyte; S7, detecting the flatness of the weld surface to determine whether to repeat the steps S5 to S7 until the flatness of the weld surface meets the requirements.

2. The weld cleaning method of claim 1, wherein, The starting condition of the constant power control mode is that the contact resistance is within a preset resistance threshold, wherein the output power of the switch mode power supply in the weld cleaning device is proportional to the contact resistance, and the contact resistance is the ratio of the output voltage to the output current.

3. The weld cleaning method of claim 2, wherein, The starting condition of the constant voltage control mode is that the output voltage of the switch mode power supply is greater than or equal to a preset voltage, and the output current is less than a preset current.

4. The weld cleaning method of claim 3, wherein, The starting condition of the constant current control mode is that the output current of the switch mode power supply is greater than or equal to the preset current, and the output voltage is less than the preset voltage.

5. The weld cleaning method of claim 4, wherein, The process of the step S3 comprises: collecting the maximum impurity thickness on the weld to be cleaned; when the maximum impurity thickness exceeds a preset thickness, determining that the wetting degree of electrolyte does not meet the requirements, and increasing the delay time period for switching from the constant power control mode or the constant current control mode to the constant voltage control mode, wherein the delay time period is positively correlated with the maximum impurity thickness.

6. The weld cleaning method of claim 5, wherein, The process of the step S5 comprises: respectively acquiring the cleaning area of the weld to be cleaned when the switch mode power supply is in the constant power control mode, the constant current control mode and the constant voltage control mode; in the area of the constant power control mode, the brush rotation speed remains unchanged; in the area of the constant current control mode, if the fluctuation amplitude of the output voltage is greater than a preset second voltage fluctuation amplitude, it is determined that the impurities in the electrolyte are dense, and the brush rotation speed is reduced; In the region of the constant voltage control mode, if the fluctuation amplitude of the output current is greater than a preset second current fluctuation amplitude, it is determined that the degree of electrolytic reaction of the weld surface to be cleaned does not meet the requirements, and the brush rotation speed is increased, Wherein, the fluctuation amplitude of the output voltage is the absolute value of the difference between the maximum and minimum values of the output voltage in the region of the constant current control mode; the fluctuation amplitude of the output current is the absolute value of the difference between the maximum and minimum values of the output current in the region of the constant voltage control mode; The brush rotation speed in the constant current control mode is inversely proportional to the fluctuation amplitude of the output voltage; the brush rotation speed in the constant voltage control mode is proportional to the fluctuation amplitude of the output current.

7. The weld cleaning method of claim 6, wherein, The process of step S5 includes: If the fluctuation amplitude of the output voltage is greater than or equal to a preset first voltage fluctuation amplitude and less than or equal to a preset second voltage fluctuation amplitude, or the fluctuation amplitude of the output current is greater than or equal to a preset first current fluctuation amplitude and less than or equal to a preset second current fluctuation amplitude, it is preliminarily determined that the impurity treatment uniformity does not meet the requirements, and the jump time resistance when the control mode is triggered is obtained; If the jump time resistance is greater than or equal to a preset jump time resistance, it is secondarily determined that the impurity treatment uniformity does not meet the requirements, and the contact area is increased, Wherein, the increase amplitude of the contact area is proportional to the jump time resistance.

8. The weld cleaning method of claim 7, wherein, The process of step S5 includes: The temperature change amount per unit time in the increased contact area of the brush is obtained; The propelling rate of the electrolyte increases with the increase of the temperature change amount, Wherein, the temperature change amount is the difference between the temperature at the end of the unit time and the temperature at the beginning of the unit time.

9. The weld cleaning method of claim 8, wherein, In step S7, if the flatness is greater than or equal to a preset flatness, it is determined that the weld cleaning is not completed; If the flatness is less than the preset flatness, it is determined that the weld cleaning is completed; Wherein, the flatness is the average impurity thickness of each position on the weld to be cleaned.

10. The method of cleaning a weld seam according to claim 1, wherein, The usage frequency of the switch mode power supply is not less than 100 kHz, and the output ripple peak-to-peak value of the output voltage is not higher than 2000 mV.

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