Měření tepelného zatížení pracovních válců při válcování za tepla.

Measurement of Thermal Load on Working Rolls during Hot Rolling

journal article in Web of Science

en

Work rolls in hot rolling mills are thermally and mechanically loaded; both of these loading aspects are difficult to measure. Laboratory tests can be used for the specification of the thermal load in the cooling area; however a thermal load in a roll gap is still difficult to measure. The paper describes an experimental technique developed for monitoring the work roll surface temperature by sensors embedded in the work roll. Continuous hot rolling pilot line trials were performed for different process conditions. One parameter, e.g. roll cooling, rolling velocity, reduction or skin cooling, can easily be changed during the trials, and the effect on the thermal cycle of the work roll can be directly measured. These thermal measurements give very detailed information about the temperature field. An inverse heat-conduction model has been developed to compute the surface boundary condition from the measured temperatures. The heat flux and heat transfer coefficient distribution along the roll circumference can be obtained afterwards. The results for different rolling velocities and reductions (up to 50%) are shown.

Měření tepelného a mechanického zatížení pracovních válců při válcování je velmi obtížné. Článek popisuje experimentální techniku, která byla vyvinuta pro monitorování povrchové teploty símači zabudovanými ve válci. Změřené teploty ve válci jsou vyhodnoceny inverzní úlohou a jasou vypočteny součnitele přestupu tepla a tepelné toky. Článek obsahuje příklady z měření na laboratorní trati.

Work rolls in hot rolling mills are thermally and mechanically loaded; both of these loading aspects are difficult to measure. Laboratory tests can be used for the specification of the thermal load in the cooling area; however a thermal load in a roll gap is still difficult to measure. The paper describes an experimental technique developed for monitoring the work roll surface temperature by sensors embedded in the work roll. Continuous hot rolling pilot line trials were performed for different process conditions. One parameter, e.g. roll cooling, rolling velocity, reduction or skin cooling, can easily be changed during the trials, and the effect on the thermal cycle of the work roll can be directly measured. These thermal measurements give very detailed information about the temperature field. An inverse heat-conduction model has been developed to compute the surface boundary condition from the measured temperatures. The heat flux and heat transfer coefficient distribution along the roll circumference can be obtained afterwards. The results for different rolling velocities and reductions (up to 50%) are shown.

válcování za tepla, tepelné zatížení, chlazení válců, koeficient přestupu tepla

hot rolling;thermal load;roll cooling;heat transfer coefficient

2013

05.03.2013

WILEY-VCH Verlag GmbH & Co. KGaA

Weinheim

1869-344X

84

3

269–275

7