Key selection parameters for ultrasonic metal spot welding machine (for charging pile applications)
When choosing a device, it is important to pay attention to the following points:
Recommended parameter/configuration requirements/description considerations for charging station applications
Charging piles with a power of 2000W-6000W or higher have large wire cross-sections (usually 16mm ² to 95mm ² or more), thick terminals, and require sufficient energy to achieve deep plastic flow.
Frequency 20kHz or 35kHz, 20kHz is more common, with moderate vibration amplitude; 15kHz has higher energy and is suitable for thicker and larger solder joints. Need to balance the appearance and penetration of solder joints.
The servo motor drive of the pressure system is superior to pneumatic. Pressure control is more precise and repeatable, achieving multi-stage precision control of “pressure displacement energy” to ensure consistent quality of each solder joint.
The rigid gantry or C-shaped frame of the nose structure ensures good system rigidity, stable amplitude, and no twisting deformation under high pressure and high-frequency vibration.
Welding mode can be selected from energy mode, height mode, and time mode. It is recommended to use the “energy+height” dual monitoring mode. Set the target energy while monitoring the depth (displacement) of the welding head’s downward pressure, and stop immediately when any condition is met, ensuring dual quality assurance.
The digital PLC/touch screen control of the control system can store hundreds of welding parameters (for different wire diameters/terminal models), monitor welding curves (energy, pressure, displacement, time) in real time, and have traceable data, meeting the quality requirements of the automotive industry.
Sonorode is a special high-strength steel or titanium alloy core component for welding heads. It is necessary to customize the contact surface pattern (tooth pattern) of the welding head according to the shape of the terminal (such as ring, fork, or sheet) to concentrate energy and prevent slipping. Professional repair is required after wear and tear.
Safety and integrated grating protection, automatic loading and unloading interface ensure safe operation, making it easy to integrate into automated production lines in the future.
Typical Welding Processes and Quality Control
1. Preparation before welding:
·Cleaning: Wires and terminals must be clean, free from oil stains and oxidation layers. Usually, physical (wire brushing) or chemical cleaning is required.
·Alignment: Use specialized fixtures to accurately fix wires and terminals, ensuring good contact in the welding area.
2. Welding process:
·Lower the welding head and apply preset pressure.
·Activate ultrasonic vibration, energy diffuses at the interface, breaks the oxide layer, and achieves interatomic bonding.
·Stop after reaching the set energy/displacement.
3. Quality inspection:
·Non destructive:
·Appearance: The solder joints should have uniform indentation, no cracks, and excessive flash.
·Pulling test (spot check): Using a tensile tester, the fracture should occur at the base material of the wire, not at the solder joint interface.
·Resistance test: Measure the circuit resistance before and after the solder joint, and the increase value should be minimal (usually<1 micro ohm).
·Destructive (regular process validation):
·Metallographic section analysis: Observe whether the interface bonding is sufficient and free of voids.
·Tear test: Tear open the solder joint and check the interface fusion area.