Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 2016

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: bark thickness

Sortuj według:

Ogranicz wyniki do:

Damage caused by harvester head feed rollers to alder, pine and spruce

Karaszewski Z., Łacka A., Mederski P. S., Noskowiak A., Bembenek M.

Drewno : prace naukowe, doniesienia, komunikaty

2016

vol. 59, nr 197

77--88

The harvester head causes damage to the bark and wood on the lateral surface of the processed assortment. The severity of the damage may be influenced by the construction of the harvester head and tree species characteristics, such as bark thickness and wood hardness. The study aimed to recognise and compare damage caused to hardwood and softwood. Wood from alder, pine and spruce was harvested using a Valmet 911.4 harvester equipped with a 360.2 head. Logs measuring 2.40 and 2.50 m in length were used in this study. The depth of the damage caused by the feed roller spikes was measured using a digital caliper. Comparison of these defects across the three species revealed that as bark thickness increased so the depth of damage to the timber decreased. Damage to the alder logs in the form of dents and gouged timber fibres was shallow: from 1.7 to 3.7 mm, and significantly less than that to the softwood logs: in the pine from 5.9 to 7.8 mm, and in the spruce from 3.9 to 5.6 mm. Damage to the middle and top logs for each species was similar and depth varied little along the entire length of the processed assortment. Such damage only slightly lowered the quality of the alder wood, which had the thickest bark. Application of the Valmet 911.4 harvester caused less damage to the alder wood than to the softwood (pine and spruce).