Automated Determination and On-Line Correction of Emissivity Coefficient in Controlled Cooling of Drop Forgings
| Periodical | Solid State Phenomena (Volume 177) |
|---|---|
| Main Theme | Control Engineering in Materials Processing |
| Edited by | Andrzej Kot |
| Pages | 76-83 |
| DOI | 10.4028/www.scientific.net/SSP.177.76 |
| Citation | Piotr Skubisz et al., 2011, Solid State Phenomena, 177, 76 |
| Online since | July, 2011 |
| Authors | Piotr Skubisz, Piotr Micek, Jan Sińczak, Marek Tumidajewicz |
| Keywords | Air-Cooling, Controlled Cooling, Direct Cooling, Drop Forging, Emissivity Coefficient, Proportional-Plus-Integral Algorithm, Thermomechanical Processing (TMP) |
| Price | US$ 28,- |
The paper presents the methodology of determination of emissivity coefficient of steel in the direct cooling temperature range, which allow self-definition of this parameter in automated temperature control system used for direct cooling of drop-forged parts. Based on the actual temperature of the surface of the workpiece, the system automatically adjusts the velocity of fan-forced air to produce desired cooling rate and course of cooling curves. To enable automatic correction of cooling rate, the system must rely on exact remote temperature measurements. This is conditioned by correct definition of emissivity in pyrometer gauge system. Traditionally, pyrometers use presets of a constant value, selected as to get optimum consistency for the temperature range concerned. As the emissivity is time-dependent, the idea of the approach presented in the paper is to use time dependent characteristics, to attain the minimum discrepancy between actual and measured values during the whole cooling cycle.