Short Arc Welding Current Control for Low-Spatter Clearing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing short arc welding systems face challenges in reducing current during the short clearing phase effectively, leading to spatter and puddle disturbance due to delayed current reduction and energy storage in inductors.
Innovation Solution
A method and system for controlling short circuit welding by increasing current in the short state, then decreasing it at a controlled rate, monitoring elapsed time and transition current, and adjusting short and arc state parameters based on past cycle comparisons to achieve a desired transition current.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If current is reduced during short clearing phase, then spatter and puddle disturbance are reduced, but current reduction is delayed due to inductor energy storage
Solution Approach 1:
The controller predicts the short clearing event before it occurs and initiates current reduction in advance. By detecting parameters such as elapsed time since the last short clearing and transition current magnitude, the system proactively adjusts the current waveform to ensure reduction is complete before the short clears, eliminating the harmful effects without delay.
Solution Approach 2:
The system dynamically adjusts the current waveform based on real-time monitoring of welding parameters. The controller modifies the current reduction rate and timing adaptively, changing the electrical characteristics in response to detected conditions such as arc voltage and current magnitude to optimize the clearing process.
2Object-affected harmful factors
If current magnitude is lowered prior to short clearing, then energy is limited and spatter is reduced, but arc stability may be compromised
Solution Approach 1:
The controller lowers the current magnitude in advance of the short clearing event, predicting when the clearing will occur based on elapsed time and transition parameters. This preliminary current reduction limits the energy available at the moment of clearing, reducing spatter while maintaining arc stability through controlled energy delivery.
Solution Approach 2:
The system continuously monitors welding parameters including current magnitude, arc voltage, and elapsed time, using this feedback to adjust the current waveform in real-time. This closed-loop control ensures the current is reduced to optimal levels before short clearing while maintaining sufficient energy for arc stability.
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 reduces spatter and puddle disturbance by ensuring a controlled current reduction during short clearing, maintaining arc stability, and allowing for adjustments to optimize subsequent welding cycles.
Implementation Method 1
The electrode, and a portion of the base metal, are melted during the short circuit transfer welding process by current flowing through the electrode to the weldment
Implementation Method 2
a welding machine used for short arc welding includes at least a power source, a controller and a wire feeder. A prior art short arc waveform from the Miller® RMD® process is shown in FIG. 1. The upper images show the wire, puddle and arc or short
Data Source
AI summary
An example method of controlling a short circuit welding process includes: setting a heat target for at least a portion of a short state; monitoring output parameters during the short state; calculating a measured heat from the measured output parameters; comparing the measured heat and the heat target; adjusting a pinch current in a subsequent short state in response to at least one comparing from at least one previous short state; and repeating these actions.