Resistive Wire Preheating to Reduce Welding Wire Cast

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing welding technologies do not effectively preheat the electrode wire before initiating a welding operation, leading to inconsistent wire placement and increased wire cast, particularly in large diameter and alloy wires, which can result in hydrogen-induced cracking and embrittlement.

Innovation Solution

A system and method that preheats the welding wire using resistive heating through a preheating circuit, eliminating mechanical straightening and ensuring consistent wire placement by applying heat to the wire using electrical contacts and a control circuit to manage current based on wire composition and diameter.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If mechanical straightening is used to reduce wire cast, then wire placement consistency may be improved, but the wire may undergo mechanical deformation and increased complexity of the system

Engineering Contradiction:
Improvewire placement consistencyVSAvoidmechanical straightening system
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent replaces mechanical straightening systems with an electrical preheating system. Instead of using mechanical rollers or straightening devices to physically manipulate the wire, the invention applies electrical current through the wire to generate heat, which reduces wire cast through thermal effects. This substitution eliminates complex mechanical components while achieving the desired wire placement consistency.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the physical state of the wire by heating it to specific temperatures before welding. By controlling the temperature parameter of the wire through electrical preheating, the system reduces wire cast and improves placement consistency without mechanical deformation. The wire is heated to a temperature range that relieves internal stresses and reduces cast formation.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If preheating is applied to reduce wire cast, then wire placement consistency improves, but energy consumption increases

Engineering Contradiction:
Improvewire placement consistencyVSAvoidenergy consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies preheating as a preliminary action before the actual welding process. By heating the wire in advance to reduce wire cast, the system improves placement consistency for the subsequent welding operation. The preheating is applied only to the portion of the wire that will be fed, and only for the brief period needed to reduce cast, minimizing total energy consumption while achieving the precision benefit.

Inventive Principle:
Principle #10Preliminary action

3Manufacturing precision

If electrical current is applied to preheat wire, then wire cast is reduced, but risk of wire melting or buckling increases

Engineering Contradiction:
Improvewire cast reductionVSAvoidwire structural integrity
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent employs dynamic control of the preheating process by adjusting electrical parameters based on wire characteristics. The system varies voltage, current, and heating duration according to wire diameter, material composition, and feed rate. This dynamic adjustment ensures the wire is heated sufficiently to reduce cast while maintaining structural integrity and preventing melting or buckling. The heating parameters are optimized in real-time based on feedback from the welding system.

Inventive Principle:
Principle #15Dynamics

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

Reduces wire cast and enhances wire placement consistency, minimizing hydrogen-induced cracking and embrittlement by ensuring the electrode wire is heated prior to welding, thus improving the quality and reliability of welds.

Implementation Method 1

A wire straightener applies heat to the welding wire to reduce cast in the welding wire without mechanically straightening the welding wire

Methodology Applied
Scientific EffectResistive heating: Joule Heating

Implementation Method 2

A wire straightener applies heat to the welding wire to reduce cast in the welding wire without mechanically straightening the welding wire

Methodology Applied
Scientific EffectHeat treatment: Heat Treatment

Data Source

PatentEP3681663B1Systems and methods to reduce cast in a welding wire
Publication Date: 2025.12.10 ILLINOIS TOOL WORKS INC
  • EP3681663B1 patent drawingFigure 1
  • EP3681663B1 patent drawingFigure 2
  • EP3681663B1 patent drawingFigure 3

AI summary

Systems, methods, and apparatus to reduce cast in a welding wire are disclosed. Example systems to reduce cast in a welding wire include a wire advancement roller configured to advance welding wire from a welding wire supply toward a welding torch; and a wire straightener configured to reduce cast in the welding wire by applying heat to the welding wire between the welding wire supply and the welding torch.