Web Width Measurement

Web width measurement provides real-time monitoring of material width during converting, extrusion, and coating operations. Roll-2-Roll Technologies offers non-contact, high-accuracy width measurement sensors that continuously monitor web width with ±0.1mm precision. Unlike manual tape measurements or narrow-field sensors, our wide-area sensors track both edges simultaneously—even when the web wanders or oscillates—providing 100% measurement coverage for quality control and process optimization.

The Challenge: Manual Measurements and Sensor Limitations

Traditional width measurement methods create safety risks and quality blind spots:

• Manual Tape Measurements: In blown film extrusion, operators use tape measures to check layflat width—a dangerous practice near moving machinery that provides only periodic spot checks, not continuous monitoring.
• Narrow Sensor Windows: Standard sensors with 10-20mm viewing areas lose the edge during web wander, creating measurement gaps that allow off-spec material to pass undetected.
• Contact Methods: Mechanical measurement devices can damage delicate webs and fail on sticky or hot materials.
• No Data Logging: Without continuous measurement data, manufacturers cannot prove compliance to customers or identify process trends.

The Solution: Continuous, Non-Contact Width Monitoring

Roll-2-Roll width measurement systems use two sensors (or one ultra-wide ODC sensor) to continuously monitor both edges of the web, calculating width in real time.

How It Works

1. Dual-Edge Detection: Sensors mounted on either side of the web detect both edges simultaneously
2. Real-Time Calculation: The controller computes width by subtracting one edge position from the other
3. Continuous Logging: Width data is logged at up to 500 Hz for 100% quality coverage
4. Automatic Alerts: Tolerance violations trigger alarms before off-spec material reaches the winder

Key Advantage: Wide viewing areas (up to 960mm per sensor) track both edges even during significant web wander, ensuring no measurement blind spots.

Key Benefits

• Eliminate Manual Measurements: Replace dangerous tape measurements with continuous automated monitoring
• 100% Quality Coverage: Every meter of web is measured, not just periodic spot checks
• Real-Time Tolerance Monitoring: Detect width deviations before off-spec material is wound
• Traceability & Compliance: Timestamped width data provides proof of quality for customer audits
• Process Optimization: Identify trends in width variation to optimize die gap, bubble pressure, or coating parameters

Applications by Industry

• Film Extrusion (Blown & Cast) — Monitor layflat width to control bubble diameter or die gap adjustments
• Battery Manufacturing — Measure electrode coating width to ensure anode/cathode overlap tolerances
• Coating & Laminating — Monitor coating width to verify coverage and detect edge beading
• Slitting Operations — Measure slit lane widths simultaneously (multi-web monitoring)
• Nonwovens — Track width on porous spunbond and meltblown webs

Related Solutions

• Edge Detection — High-precision edge position measurement
• Center Guiding — Guide webs by detecting both edges
• Thread Counting — Count and measure individual threads