Magnetostrictive transducer for hot rolling mill manufacturer
Find out how to control the compression roller in rolling mill
The HYPERWAVE WRA-S magnetostrictive transducer allows to control the lamination process in the hot rolling mill manufacturer thanks to:
- robust product for increased reliability to work in harsh operating conditions;
- signal stability in high vibration environments;
- high working temperature of 90°C;
- resolution up to 0.5 𝜇m;
- linearity error: 0.01% FS;
- highest accuracy of transmitted data.
Overview
- Application: Accurate control of the compression roller in rolling mill
- Product: Magnetostrictive transducer WRA-S – stroke 550 mm.
- Result: WRA-S controls the cylinder position with a resolution of 0.05 µm.
The process
Hot rolling is part of a very long and complex process.
The cold steel billets or ingots are heated to temperatures close to melting (1150° to 1220°) in order to allow for the rolling process to elongate them by compressing several times through calendaring stations, that reduce their size.
The challenge
The rolling process reduces the size from one station to another in a very strict and calibrated way according to the need of required finished product.
To achieve this result, each rolling station must accurately control the micrometric distance between the two elongation rollers. The movement of the cylinders and the stability of the position is achieved by using 4 hydraulic cylinders that keep the two rollers close together. At least one of the cylinders, in pairs of the two, must have in parallel a precise position control with the fastest possible update time.
Additional station may be needed to carry out further micro corrections not correctly managed by the previous station depending on the accuracy needed for the final product.
Product benefits
- Robust product for increased reliability for working in harsh and demanding operating conditions.
- Signal stability in high vibration environment
- High working temperature of 90°C
- Resolution up to 0.5 𝜇m
- Linearity error: 0.01% FS
Solution
The position transducers HYPERWAVE WRA-S using Magnetostrictive technology with 0.5 µm resolution and sampling time of 500 µS satisfies the rapid response time and accuracy needed by the rolling mill.
The operating temperature is up to 90° C, the synchronous serial communication (SSI) that communicates with a single and dedicated connection directly (no fieldbus) with the PLC makes the system highly reliable and sensitive enough to perform minor most correction for the best accuracy.
The transducers are installed in the hydraulic cylinders to have both, a direct reading without intermediate mechanical space and to better protect the transducers from any incandescent burrs.
The model selected is the WRA-S, SSI output ,550 mm synchronous stroke with 25 bits and Gray coding to allow high resolution and protect accuracy of the transmitted data.
