Due to its high production efficiency, low cost and material saving, spot welding machine is widely used in crafts, electronic components, instruments and meters, electrical switches, cable manufacturing, muffler, metal packaging, chemical containers and other industries. The working principle of spot welding machine is to use the high-temperature arc generated by the instantaneous short circuit between the positive and negative poles to melt the solder and welded materials on the electrode, To achieve the purpose of combining them. The process parameters affecting the welding quality of spot welder include welding current, electrode pressure, energization time and electrode working surface size.
The spot welding machine will encounter some common faults in use, and the corresponding solutions are analyzed as follows:
Splash:
a. Check whether the electrode head is seriously oxidized.
b. Check whether the welding workpiece is seriously rusted and has poor contact.
c. Check whether the adjustment switch is too high.
d. Check whether the electrode pressure is too low and whether the welding procedure is correct.
Insufficient workpiece strength:
a. Check whether the electrode pressure is too small and whether the electrode rod is fastened.
b. Check whether the welding energy is too small and whether the welding workpiece is seriously rusted, resulting in poor contact of the welding joint.
c. Check whether there is too much oxide between the electrode head and the electrode rod, the electrode rod and the electrode arm.
d. Check whether the cross section of the electrode head increases due to wear, resulting in the reduction of welding energy.
e. Check whether the electrode and copper flexible joint and joint surface are seriously oxidized.
Overheating:
a. Check whether the insulation resistance between the electrode base and the body is poor, resulting in local short circuit.
b. Check whether the water inlet pressure, water flow and water supply temperature are appropriate, and check whether the waterway system is blocked by dirt, resulting in overheating of electrode arm, electrode rod and electrode head due to poor cooling.
c. Check whether the copper flexible coupling, electrode arm, electrode rod and electrode head contact surface are seriously oxidized, resulting in increased contact resistance and serious heating.
d. Check whether the cross section of electrode head increases too much due to wear, which makes the welding machine overload and heat.
e. Check whether the welding thickness and load duration exceed the standard, so that the welding machine is overloaded and heated.
Severe indentation and extrusion:
a. Check for excessive current.
b. Check whether the welded workpiece is uneven.
c. Check whether the electrode pressure is too large and whether the shape and section of the electrode head are appropriate.
Gloves, aprons and protective glasses shall be worn during the operation of spot welding machine to avoid burns caused by sparks flying out. The sliding part shall be well lubricated, and the metal splash shall be removed after use. With the deformation and wear of the electrode end, the contact area increases and the strength of the solder joint decreases. Oxides, dirt, oil and other impurities on the workpiece surface increase the contact resistance. Too thick oxide layer will even prevent current from passing through.
