Dual-Arc Welding Torch for High Deposition With Low Heat Input
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current welding technologies face challenges in achieving high deposition rates with low heat input, particularly in thin materials and complex joint designs, often resulting in arc instability and increased complexity, while also being cost-prohibitive for widespread adoption.
Innovation Solution
A method and apparatus for arc welding that utilizes a non-consumable electrode to generate a broadened plasma for preheating and melting a consumable wire electrode, with a separately focused plasma jet for the workpiece, allowing independent control of the consumable wire electrode melt rate and workpiece heat input, utilizing advanced electrode cooling and power source management to achieve high energy density and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional single-arc welding is used, then the process is simple and stable, but the deposition rate is limited and heat input cannot be independently controlled
Solution Approach 1:
The welding system divides the arc into two separate arcs with independent power sources, allowing independent control of heat input and deposition rate. Each arc is controlled by a separate power source, enabling the first arc to control heat input to the workpiece while the second arc controls wire feed and deposition, thus resolving the contradiction between high deposition rate and process simplicity.
2Productivity
If multiple wire sub-arc welding is used for high deposition, then the deposition rate increases, but the process is limited to specific joint positions and the fluidity of the pool causes stability issues
Solution Approach 1:
The system separates the functions of the two arcs: the first arc provides stable heat input control to the workpiece, while the second arc handles wire melting and deposition. This segmentation allows the process to maintain stability through independent power source control, eliminating the pool fluidity issues that plague conventional multi-arc systems, while achieving high deposition rates.
3Productivity
If twin GMAW with combined droplets is used, then high deposition is achieved, but arc instability increases and the process becomes more complex
Solution Approach 1:
Instead of combining droplets from two electrodes as in conventional twin GMAW, this system uses two separate power sources to independently control two arcs. The first power source controls heat input through a non-consumable or consumable electrode, while the second power source controls wire feed and melting. This segmentation maintains arc stability by preventing droplet interaction while achieving high deposition through independent control of both arcs.
4Manufacturing precision
If laser-based systems are used for high energy density, then precision and control are improved, but the cost becomes prohibitive for widespread adoption
Solution Approach 1:
The system replaces the laser-based mechanical/optical system with an electrical arc-based system using two independent power sources. This substitution maintains the high energy density and precise heat input control characteristics of laser systems while using more cost-effective electrical arc technology, making the solution economically viable for widespread adoption in industrial welding applications.
5Productivity
If high deposition welding is used for thick workpieces, then productivity increases, but heat input becomes excessive causing distortion
Solution Approach 1:
The dual power source system segments the control of heat input and deposition rate. The first power source is dedicated to controlling heat input to the workpiece, while the second power source controls wire feed and deposition rate. This allows the operator to maximize deposition rate through the second arc while the first arc precisely controls heat input levels, preventing excessive heat accumulation and distortion even during high-productivity welding of thick workpieces.
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 enables high deposition rates with controlled heat input, reducing arc instability and complexity, and is cost-effective compared to laser-based systems, offering versatility across various materials and applications from thin to thick plates with reduced distortion and spatter.
Implementation Method 1
arc energy is split into a broadened plasma to spread over, pre-heat, and melt a consumable wire electrode
Implementation Method 2
broadened plasma to spread over, pre-heat, and melt a consumable wire electrode
Implementation Method 3
sharpened plasma jet with focused intensity is arranged to melt the workpiece
Implementation Method 4
sharpened plasma jet with focused intensity
Implementation Method 5
advanced electrode cooling
Implementation Method 6
advanced electrode cooling and power source management to achieve high energy density and stability
Data Source
AI summary
An arc welding apparatus and corresponding method includes a torch, a non-consumable electrode and a consumable electrode both disposed within the torch, a wire feeder configured to feed the consumable electrode in a vicinity of the non-consumable electrode, a first power source and a second power source that provide independent current, respectively, to the non-consumable electrode and the consumable electrode, and a weld process controller to control outputs of the first power source and the second power source such that a concentrated arc is formed, as a heat source, between the non-consumable electrode and a workpiece, and an inter-electrode arc is formed between the consumable electrode and the non-consumable electrode to melt the consumable electrode. The approach is characterized by low heat input, low distortion, low spatter, and the relative high speed or high deposition of laser and laser-MIG hybrid and other forms of multi-wire/multi-electrode welding, cladding, and additive manufacturing.