| 摘要 |
<p>PURPOSE:To surely enhance the stabilization of the quality of a steel pipe even in an unsteady condition and to improve the yield by heating pipe materials for seamless steel pipe in a rotary hearth type heating furnace and extracting them according to an extraction pitch obtd. from the fuzzy theory and rolling them. CONSTITUTION:After a billet 1 for pipe material is heated in the rotary hearth type heating furnace 2, the heated billet is extracted from the furnace and rolled with the rolling mills 3-7 in order to produce a seamless steel pipe. Then, heating temp. error is obtd. from a difference between the calculated value and the aimed value of the heating temp. at the time of extracting the pipe material 1, and based on the error and the fluctuation of the rolling pitch in the rolling process, the extraction pitch of the pipe material 1 from the heating furnace 2 is controlled. In the extraction control method, the fuzzy theory obtained by making the heating temp. error and the rolling pitch fluctuation an antecedent part variable and making a factor decided by applying a fuzzy control rule a consequent part variable, is used to find the ejecting pitch. According to the extraction pitch, the extraction pitch of the pipe material 1 from the heating furnace 2 is controlled.</p> |
