Abstract
Workpiece feed speed can be increased while maintaining product dimension accuracy by proportionately increasing saw rotation speed. However, the required saw speed increase is acceptable only if the speed does not approach the saw critical speed. Tensioning can be used to increase critical speed, but the amount of tensioning possible is limited by saw “dishing.” This dishing makes saw leveling very difficult. This study demonstrates the concept of using temporary tensioning to overcome the dishing limitation. Normally, the saw is only moderately tensioned. However, after installation in the sawing machine, the tensioning can be increased temporarily, here by thermal means. In this way, the saw is highly tensioned while in operation, but only lightly tensioned during maintenance. The preliminary experiments presented in this study demonstrate this concept, and confirm that a workpiece feed speed increase of more than 50% is possible by using temporary tensioning.
Zusammenfassung
Durch Erhöhen der Umlaufgeschwindigkeit kann der Durchsatz an Werkstücken unter Beibehaltung der Schnittgenauigkeit gesteigert werden, solange die Kreissäge unterhalb der kritischen Geschwindigkeit bleibt. Diese kann einerseits durch Vorspannen erhöht werden, ist aber andererseits begrenzt durch das Auftreten von “Tellereffekten”. In dieser Arbeit wird die Methode eines temporären Spannens vorgestellt, das diese Probleme umgeht. Das Sägeblatt wird nur mäßig vorgespannt. Nach dem Einbau kann die Spannung vorübergehend durch thermische Behandlung erhöht werden. Es wird gezeigt, daß damit die Umlaufgeschwindigkeit um bis zu 50% erhöht werden kann.
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This work was financially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC). Mr. Ed Komori of Seneca Systems, Inc. Generously provided the experimental sawblade. Mr. Darrell Wong kindly assisted with the manuscript.
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Schajer, G.S., Kishimoto, K.J. High-speed circular sawing using temporary tensioning. Holz als Roh- und Werkstoff 54, 361–367 (1996). https://doi.org/10.1007/s001070050202
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DOI: https://doi.org/10.1007/s001070050202