Optical Fiber Calibrating Bar for Precise Multi-Roll Leveller Setup
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing calibration devices for multi-roll levellers are not adaptable to different designs and can be damaged during use, lacking precision and reproducibility in determining key parameters for efficient levelling operations.
Innovation Solution
A calibrating bar with embedded optical fibers and fiber Bragg gratings on both sides of a neutral plane, connected to an optical coupler, measures strain by optical frequency domain reflectometry, compensating for temperature changes by using optical fibers in compression and traction, allowing precise calibration without damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a rigid measurement bar with extensometers is used for calibration, then elastic deformations can be measured, but the device lacks adaptability to different leveller designs and the extensometers can be damaged during calibration
Solution Approach 1:
The calibrating bar is designed with a universal structure that can be used on different leveller designs. The optical fibers are embedded within grooves in the bar, protecting them while allowing the bar to function across multiple leveller configurations with different roll center-to-center distances
Solution Approach 2:
The patent replaces mechanical extensometers with embedded optical fibers containing Bragg gratings. This substitution eliminates the fragility of mechanical extensometers while maintaining measurement capability, as the optical fibers are protected within grooves in the calibrating bar
2Measurement precision
If extensometers are placed between upper and lower rolls for measurement, then elastic deformations can be measured, but the extensometers are vulnerable to damage during the calibration process
Solution Approach 1:
The patent replaces mechanical extensometers with optical fibers embedded in grooves within the calibrating bar. This substitution protects the measuring elements from damage while maintaining measurement capability, as the optical fibers are integrated into the bar structure rather than being external attachments
Solution Approach 2:
The optical fibers are nested within grooves in the calibrating bar, with the fibers positioned inside protective cavities. This nesting arrangement protects the fragile optical measuring elements from mechanical damage during calibration operations
3Productivity
If traditional calibration methods are used, then calibration can be performed, but the process lacks precision and reproducibility in determining key parameters
Solution Approach 1:
The patent uses optical frequency domain reflectometry to measure strain along the optical fibers, providing precise and reproducible measurements of the calibrating bar deformation. This optical measurement system offers superior precision compared to traditional mechanical measurement methods
Solution Approach 2:
The calibration process uses the measured strain data from the optical fibers to provide feedback for adjusting the leveller parameters. This feedback mechanism enables precise determination of key calibration parameters such as roll play, spring, and bending characteristics
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
Enables precise and reproducible calibration of multi-roll levellers across different designs, ensuring accurate measurement of strain without damaging the measuring means.
Implementation Method 1
said first optical fibre and said second optical fibre comprising a fibre Bragg grating
Implementation Method 2
measures strain by optical frequency domain reflectometry
Implementation Method 3
said first embedded optical fibre and said second embedded optical fibre being configured such that they can be connected to an optical coupler... measures strain by optical frequency domain reflectometry, compensating for temperature changes by using optical fibers in compression and traction
Data Source
Figure 1~3
Figure 4~5
Figure 6~7
AI summary
The invention relates to a calibrating bar, for calibrating a multi-roll leveller for metal strips, said calibrating comprising - a first groove on a first face wherein a first optical fibre is embedded by means of an adhesive, - a second groove on a second face, being opposite to said first face, wherein a second optical fibre is embedded by means of an adhesive, - said first optical fibre and said second optical fibre comprising a fibre Bragg grating and being essentially parallel, - said first optical fibre and said second optical fibre being located at the same distance from said neutral plane N, - said first embedded optical fibre and said second embedded optical fibre being configured such that they can be connected to an optical coupler and such that it has a sufficient length to extend over all the rolls of said multi-roll leveller.