Stroke is the magnitude of the oscillation. Hydraulic oscillators are becoming more popular. They're a motor driving a gear box which is turning a cam or short lever. But hydraulic oscillators allow quick-changing of both stroke and frequency. This greater control over oscillation can improve surface quality because the mill can tailor oscillation for each grade.
Mills also can increase casting speed by increasing oscillation.
This integrates the mold and the oscillator into one unit. A computer changes the oscillation automatically based on the grade family. The Ipsco mold will have 60-percent less oscillation mass than a conventional oscillator because of the integrated design, Ashburn says. The resonance mold has copper plates and water jackets suspended on leaf springs. So the mass being oscillated is much less.