Improvements in Rolling Mill Preset Screw-Down Controllers

In the rolling mill screw-down pre-positioning control system discussed in this paper, the use of electronic-balance detectors and anticipators permits higher screw-down motor speeds without loss of accuracy in the final positioning of the rolls. The electronic-balance detectors replace polarized contact-making ammeters while balance anticipators permit the introduction of slow-down motor circuits for accurate stopping. This latter feature could not be provided so readily by the earlier control method. A new system of schedule panels on which one or more complete rolling schedules may be preset is a definite and important improvement over the earlier design. In the new panels, it is necessary to locate only two plugs for each pass per schedule while in the older method employing cords, it was necessary to locate both ends of two cords, making four connections per pass per schedule. Freedom from the complicated network of cords makes the set-up procedure more rapid and certain.