Shape Meter Measurement Systems
Why strip shape is critical to product quality
What is a shape meter measurement system?
A shape meter measurement system is a specialized sensor solution that quantitatively assesses and controls the flatness of the strip during processing. It provides real-time data on shape deviations, expressed in I units, where 1 I unit corresponds to a length difference of 10 µm per meter of strip width.
It’s important to distinguish between “flatness” and “levelness.” While levelness refers to surface height deviations when laid on a flat plane, flatness describes internal stress distribution across the strip width. That distribution determines how the strip behaves under tension—how it will slit, bend, or wrap—and ultimately, whether it passes final inspection.
Full-spectrum shape meter measurement from Friedrich Vollmer
Friedrich Vollmer offers a comprehensive portfolio of solutions for precise, real-time flatness measurement in all key production environments:
BFI shape meter roll
Developed under license from the VDEh-Betriebsforschungsinstitut (BFI), the BFI roll features a solid steel roll body with a homogenous outer surface. Inside, piezoelectric sensors monitor stress differentials as the strip passes across the roll.
Typically replaces an existing deflector roll
Available with various surface coatings (steel, tungsten carbide, rubber, chrome)
Regrindable using standard roll grinding equipment
Measuring zone widths from 17 mm and up, fully customized
TCP/IP data communication enables seamless integration into modern plant networks
Segmented shape rolls for stretch-bend levelers
In tension-leveling and straightening lines, Vollmer's segmented shape rolls offer zone-based measurement through individual sensorized segments:
Each segment is a coated ring rotating on low-friction bearings around a fixed central axis
Strain gauge sensors inside the axis measure radial force per zone
Operates without auxiliary drive—ideal for low strip tension or small wrap angles
Communication supported via TCP/IP, Profinet, analog and digital I/Os
Automatic flatness control (AFC)
Measuring strip shape is only the first step. Vollmer systems also support Automatic Flatness Control (AFC), closing the feedback loop between sensor data and actuator response.
When integrated into mills equipped with adjusting actuators—such as:
Work roll bending
Intermediate roll shifting
Roll tilting
Zone cooling systems
—Vollmer’s AFC module dynamically adjusts rolling parameters to maintain flatness within defined I-unit thresholds.
This leads to:
Fewer strip breaks
Reduced out-of-spec production
Higher line speeds with confidence
Improved customer satisfaction through documented flatness compliance
Typical control accuracy of ±4 I-units is achievable relative to the nominal shape curve, making AFC a cornerstone for producers in aerospace, automotive, and electronics steel grades.
Ready to take control of strip shape?
Precision strip shape measurement is no longer optional—it’s essential to meet the demands of today’s high-performance industries. Whether you're running high-speed cold mills or delicate tension leveling lines, Vollmer's shape meter measurement systems give you the data and control needed to optimize productivity and deliver certified quality.
Contact us today for a tailored consultation and discover how shape measurement can transform your line performance.