Short-Circuit Welding Waveform Control for Low-Spatter Penetration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pulsed and short circuit welding regimes face challenges such as limited travel speed, excessive spatter, less than optimal penetration, and excessive energy addition to the weld, particularly with cored wire electrodes.
Innovation Solution
A welding method that generates a control waveform with successive peak phases followed by a short circuit between the welding wire electrode and the advancing weld puddle, with each peak phase regulated based on the immediately preceding short circuit to control the subsequent short circuit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If pulsed welding processes are used to control short circuits between electrode and workpiece, then welding quality and flexibility improve, but excessive energy is added to the weld particularly with cored wire electrodes
Solution Approach 1:
The patent applies periodic pulsed current waveforms to the welding electrode, creating cyclic peaks and valleys in current flow. This periodic action allows controlled short circuits between electrode and workpiece while managing energy input. The pulsed regime enables precise control of heat input and welding parameters, improving weld quality without excessive energy addition to cored wire electrodes.
Solution Approach 2:
The patent dynamically adjusts welding parameters including current amplitude, pulse frequency, and duty cycle to optimize the balance between welding quality and energy input. By changing these parameters in response to welding conditions, the system maintains high-quality welds while preventing excessive energy addition that would cause arc flaring in cored wire electrodes.
2Productivity
If current is increased to clear short circuits, then welding progress continues, but excessive heating of cored wire sheath causes arc to flare
Solution Approach 1:
The pulsed current waveform creates periodic opportunities for short circuit clearing without sustained high current exposure. During valley portions of the pulse waveform, current is reduced allowing wire sheath to cool, preventing excessive temperature buildup and arc flaring while still enabling progress through controlled short circuits during peak portions.
Solution Approach 2:
The pulsed waveform design anticipates potential overheating by incorporating lower current valley periods between high current peaks. This beforehand cushioning allows the wire sheath to dissipate heat before the next peak, preventing the cumulative heating that would lead to arc flaring while maintaining welding productivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach improves weld quality and flexibility by controlling short circuits to avoid excessive energy addition, reduce spatter, and maintain optimal arc length, thereby enhancing travel speed and penetration.
Implementation Method 1
Electrical power is applied to the welding wire and a circuit is completed through the workpiece to sustain an arc that melts the wire and the workpiece to form the desired weld
Implementation Method 2
sustain an arc that melts the wire and the workpiece
Implementation Method 3
current and/or voltage pulses are commanded by the power supply control circuitry to regulate the formation and deposition of metal droplets
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A welding system and method provide for generating a controlled waveform for welding power output, the waveform comprising a plurality of successive peak phases followed by a short circuit between a welding wire (42) electrode and an advancing weld puddle (148). Each then present peak phase is regulated based upon at least the immediately preceding short circuit to control the short circuit that will occur following the then present peak phase. Some embodiments permit regulating at least one waveform phase based upon at least the immediately preceding short circuit to control the next short circuit that will occur, and regulating at least one short response phase based upon at least the immediately preceding short circuit to control the next short circuit that will occur.