(1) first check the weld surface with or without corrosion, oil and other impurities, or uneven, poor contact, this will make the contact resistance increases, the current decreases, the welding surface temperature is not enough.
(2) Check whether the overlap amount of the weld is normal, and whether or not the driving side lap amount is reduced or cracked. The reduction in the amount of overlap will make the combined area of the front and rear strip too small, so that the total force surface can not bear the greater tension. In particular, the driving side of the cracking phenomenon will cause stress concentration, leaving the cracks more and more, and finally pull off.
(3) Check whether the current setting is in accordance with the technical requirements, and whether there is no corresponding increase in the current setting when the thickness of the product is changed, so that the welding current is insufficient and the welding is poor.
(4) Check the pressure of the welding wheel is reasonable, if the pressure is not enough, the contact resistance will be too large, the actual current decreases, although the welding controller has a constant current control mode, but the resistance increases more than a certain range (usually 15%) , It will exceed the limit of current compensation, the current can not increase with the corresponding increase in resistance, can not set the value. In this case the system will work when the alarm will be issued.
In actual operation, if the moment can not analyze the exact cause of the occurrence of Weld, you can clean the head and tail after the clean, increase the amount of welding lap, the appropriate increase in welding current and welding pressure and then welding a welding, and welding Pay close attention to the formation of the weld state, in most cases can be a good emergency treatment problems. Of course, if there are control system problems, or grid voltage fluctuations so that the weld Weld must take other measures to be addressed.