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- Meulenberg, Vanessa, 1993-, et al.
(författare)
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Minor cutting edge angles of sawing teeth: effect on cutting forces in wood
- 2022
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Ingår i: European Journal of Wood and Wood Products. - : Springer. - 0018-3768 .- 1436-736X. ; 80:5, s. 1165-1173
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Tidskriftsartikel (refereegranskat)abstract
- Optimising the cutting tool geometries can reduce waste while increasing timber yield. The industry is moving towards thin-kerf bandsawing of timber, and therefore, the geometry of the minor cutting edge and minor first flanks of cutting teeth become more important. Six cutting teeth with varying minor cutting edge angles (0°, 2°, 4°, 6°) and minor cutting edge clearance angles (2°, 4°, 6°) were tested by cutting into the heartwood and sapwood of frozen and non-frozen Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). Single cutting tooth tests were conducted, and the cutting and feeding forces were measured. The cutting forces were higher for Scots pine due to its higher density. Frozen sapwood resulted in higher cutting forces. The feeding force of frozen sapwood stood out as it was highly negative (i.e. self-feeding) compared to frozen heartwood, non-frozen heartwood and non-frozen sapwood. An increase in the minor cutting edge angle and minor cutting edge clearance angles, and therefore more room for elastic spring-back, can lead to up to less friction and 40% lower cutting forces. Higher minor cutting edge angles and minor cutting edge clearance angles resulted in less-negative feeding forces (i.e. less self-feeding) for frozen sapwood but remained relatively unchanged for the other wood conditions.
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| 2. |
- Meulenberg, Vanessa, 1993-, et al.
(författare)
-
Minor cutting edge force contribution in wood bandsawing
- 2022
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Ingår i: Journal of Wood Science. - : Springer. - 1435-0211 .- 1611-4663. ; 68
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Tidskriftsartikel (refereegranskat)abstract
- As the sawmill industry is moving towards thinner bandsaws for higher yields, it is important to study the cutting force in more detail. The cutting force can be split into two zones. Zone I concerns the force on the major cutting edge as well as the friction force on the major first flank. Zone II considers the forces on the minor cutting edges as well as the friction forces on the minor first flanks. Zone II cutting can significantly affect the cutting force and has not been studied in great detail. Frozen, non-frozen and dry heartwood of Norway spruce and Scots pine were cut using different tooth geometries and the cutting force was measured. The major cutting edge, clearance, band thickness, minor cutting edge angle and minor cutting edge clearance angle were investigated. The y-intercept of the cutting force–width graph was used as the Zone II force (at this point the Zone I forces are assumed to be zero). The Zone II force contribution to the cutting force was studied. The results show that frozen wood has less elastic spring-back and therefore less Zone II cutting. Dried wood showed a significantly higher degree of Zone II cutting (55−75% contribution to the cutting force). Changing the major cutting edge from 2.87 mm to 1.6 mm resulted in 10–15% higher Zone II force contributions.
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