
We invented the patented award-winning Arc Position Sensing (APS) technology at the US Department of Energy’s National Energy Technology Laboratory with the goal to improve vacuum arc remelting (VAR) and electro-slag remelting (ESR) processes.
Until now, there has been no way to “see” the electric arcs during melting or quantify the relationship between arc location and defects. APS solves this problem by tracking the positions of arcs in real time during the melting process, providing two distinct advantages over previous technology:
- Advanced furnace process control: VARmetric™ simultaneously monitors all existing process measurements along with the arc distribution and motion. This provides the necessary feedback to improve process control, leading to defect reduction, increased yield, lower costs, and greater reliability.
- Improved safety: VARmetric™ automatically identifies undesirable operating conditions such as side-arcing or asymmetric arc distributions and can issue a warning or take measures automatically to avoid these deleterious conditions.
ObserVAR™ and AnalyVAR™
ObserVAR™ and AnalyVAR™ software tools are integral parts of the VARmetric™ system. Together, they visualize and interpret results. ObserVAR™ provides real-time information and event detection during melts. AnalyVAR™ processes the data, generates reports on arc distributions during melts, and indicates the quality of the melt.
ObserVAR™ features real-time APS and ingot height calculation, anomalous event detection, side-arc detection, improved safety features, vertical and overhead arc distributions, and the option to integrate automatic feedback into your furnace.
AnalyVAR™ features variable APS melt scans displaying the vertical and overhead arc distributions, ingot height calculation, automatic report generation, and defect probability calculations through advanced solidification modeling.


VARmetric™ Applied
A. Since each furnace is unique, AmpSci performs multi-physics modeling to inform Arc Position Sensing.
B. With ObserVAR™ software, arcs are imaged and displayed in real time.
C. The distribution of the arc over time, as seen by ObserVAR™. Arc distributions often vary dramatically within a single melt without indication on standard process signals.
D. Solidification models using VARmetric™ data indicate how important the arc distribution is in achieving high ingot quality and yield.
VARmetric™ Features
What it does
- Arc position sensing (APS)
- APS synchronized with existing process signals
- Analog APS output
- Anomalous event detection
- Side-arc detection
- Integration with solidification models
- Ingot height tracking
- Electrode tip mapping
How it does it
- Completely passive monitoring of VAR furnace operations
- Real-time monitoring with ObserVARTM software
- Complete furnace process analysis with AnalyVARTM
- Automatic report generation
Where it goes
- Applicable to any arc furnace dimensions
- Equally applicable to retrofit or new furnace installation
- Little to no down time is required for installation
