Experimental Study of Interfacial Heat Flux and Surface Temperature by Inverse Analysis with Thermocouple (Fully Embedded) during Hot Steel Strip Rolling

Abstract

Knowledge of temperature distribution in the roll is fundamental aspect in cold rolling. An inverse analytical method has been previously developed to determine interfacial heat flux and surface temperature by measuring the temperature with a thermocouple (fully embedded) at only one point inside the roll. On this basis some pilot mill tests have been performed. The temperature sensor, the calibration procedure and rolling tests at different strip rolling conditions (5%, 10%, 15% and 20%) are described. Results show a good agreement with well-known theoretical models. Moreover the CPU times of the method (around 0.05 s by cycle) enable an online control of the rolling process.

Three-dimensional elasticity based on quaternion-valued potentials

“…Thus, the contact between the product and the tool can be characterized during the process. Experimental tests that confirm the feasibility of such an approach have been performed by Weisz-Patrault et al (2012b) and Legrand et al (2012Legrand et al ( , 2013. This kind of recent works contributes to renew the interest for potential theory because of their practical and technical content.…”

Temperature and heat flux fast estimation during rolling process

“…The method is very fast (0.05 sec by cycle) and relies on the 2D unsteady heat equation. Weisz-Patrault et al [19] proposed also an experimental study to show how the thermocouple can be inserted inside the roll and how it can be calibrated. The wires are evacuated by the center of the cylinder and signals are transmitted by inductive system.…”

“…It is obvious that the closer from the surface the sensor is fixed and the lower the attenuation level of the signal from the surface is, but ratios presented in figure 5 give precisely quantitative attenuation level as a function of the radius. It has been demonstrated by Weisz-Patrault et al [19] and Legrand et al [20] that it is possible to insert a thermocouple at around 0.5 mm from the surface of the roll, that is why this depth has been chosen in the following.…”

Experimental evaluation of contact stress during cold rolling process with optical fiber Bragg gratings sensors measurements and fast inverse method

“…An extension in three dimensions (with several points aligned along the roll axis) has been also developed by Weisz-Patrault et al (2013b) for stresses and Weisz-Patrault et al (2014b) for temperature. Pilot tests have been performed for thermal inverse problems dedicated to heat flux determination in the roll gap by Weisz-Patrault et al (2012b) and Legrand et al (2012a) with detailed experimental apparatus (insertion of the thermocouple under the roll surface etc...) and calibration procedures, and by Legrand et al (2013) with a specific study on thermal fatigue of rolls. More recently, Weisz-Patrault (2015) proposed a semi-analytical inverse method based on conformal mapping techniques applied for latent flatness defect detection during rolling process.…”