Horizontal Fillet Welding Arc Voltage Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Horizontal fillet welding on medium-to-thick plates faces challenges in achieving large leg length and high welding rate without causing inferior bead appearance and welding defects like undercuts and overlaps due to gravitational effects on the molten pool.
Innovation Solution
A horizontal fillet welding method where the arc voltage at the standing-plate-side weaving edge is set to be lower than or equal to the welding-line center position, and the arc voltage at the bottom-plate-side weaving edge is higher than or equal to the welding-line center position, with controlled voltage changes in a linear, stepwise, or curved manner to prevent undercuts and overlaps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the welding rate is reduced to increase the amount of weld deposition, then the leg length and bead width are improved, but the production efficiency decreases
Solution Approach 1:
The welding current is dynamically adjusted during the weaving operation. The current is increased at the intermediate weaving portion and decreased at the weaving edges, allowing the welding parameters to adapt to the positional requirements and achieve both large leg length and high welding rate
Solution Approach 2:
The welding current parameter is changed according to the weaving position. By increasing current at the intermediate portion and decreasing it at edges, the method achieves optimal weld deposition distribution that satisfies both geometric requirements and productivity goals
2Productivity
If the welding current is increased to maintain weld deposition at high welding rate, then the productivity is improved, but the arc force pushes the molten pool rearward causing undercuts and poor bead appearance
Solution Approach 1:
Different welding current values are applied at different locations during the weaving operation. The intermediate weaving portion receives higher current for adequate deposition, while the edges receive lower current to prevent undercut and maintain bead quality
Solution Approach 2:
The welding current parameter is dynamically changed based on the weaving position to simultaneously achieve high welding rate and good bead appearance
3Manufacturing precision
If the arc voltage is increased and arc length is extended to reduce arc force, then the bead appearance is improved, but welding defects occur due to poor weld penetration and deteriorated shielding performance
Solution Approach 1:
Instead of changing arc voltage and length, the invention changes the welding current parameter dynamically during weaving to control arc force, maintaining both good bead appearance and adequate weld penetration
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 method effectively suppresses the occurrence of inferior bead appearance and welding defects, ensuring favorable bead shape and penetration by managing arc voltage differences between the standing-plate-side and bottom-plate-side weaving edges.
Implementation Method 1
When performing horizontal fillet welding on a medium-thickness or thick plate by using a consumable-electrode arc welding method
Implementation Method 2
the increased amount of weld deposition and the reduced viscosity of the molten pool cause the molten pool at a standing plate side to drip toward a bottom plate due to the effect of gravitational force
Implementation Method 3
because the arc force applied to the molten pool increases as the welding current increases, the molten pool directly below the arc is pushed rearward
Data Source
AI summary
A welding system that, using a junction at which a standing plate and a bottom plate meet as a welding line, makes an electrode weave centered on the welding line and thereby welds along the welding line. In this welding system, control is performed such that the arc voltage at a standing-plate-side weaving edge is equal to or less than the arc voltage at a welding-line center position, such that the arc voltage at a bottom-plate-side weaving edge becomes equal to or greater than the arc voltage at the welding-line center position, and such that the arc voltage at the standing-plate-side weaving edge becomes lower than the arc voltage at the bottom-plate-side weaving edge. The system can suppress occurrence of inferior bead appearance and of welding defects in horizontal fillet welding.