CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

The influence of material properties on the amount of twist of spruce wood during kiln drying

A. Straze ; Robert Kliger (Institutionen för bygg- och miljöteknik, Konstruktionsteknik) ; M. Johansson ; Z. Gorisek
European Journal of Wood and Wood Products (0018-3768). Vol. 69 (2011), 2, p. 239-246.
[Artikel, refereegranskad vetenskaplig]

The development of twist in Norway spruce boards (Picea abies Karst.) during normal temperature kiln drying was researched. Tangentially oriented boards were sawn from diametrical radial planks, from which the basic wood properties, i.e. linear shrinkage and grain angle, were determined. The unrestrained boards were kiln dried using a selected drying schedule. During the controlled drying process the moisture content (MC) and twist of the boards were measured. Twist was generally induced by the shrinkage of wood below the fibre saturation point, and increased in proportional to the decrease in MC. The earlier appearance of twist, with regard to MC and drying time, was confirmed in the case of boards sawn from the central part of logs. The final twist amounted to between 10 and 20A degrees/m in the case of boards close to the pith, and decreased to less than 4A degrees/m in the case of boards sawn at a radius of 70 mm from the centre of the logs. Ring curvature had the highest impact on the final twist of the dried boards, followed by grain angle and tangential shrinkage.

Nyckelord: ponderosa pine studs, norway spruce, shape stability, picea-abies, moisture variation, compression wood, spiral grain, part 1, timber, shrinkage

Denna post skapades 2011-05-20.
CPL Pubid: 140856


Läs direkt!

Länk till annan sajt (kan kräva inloggning)

Institutioner (Chalmers)

Institutionen för bygg- och miljöteknik, Konstruktionsteknik



Chalmers infrastruktur