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• 1. [Article] Effect of kiln conditions on the strength of Douglas fir and western hemlock

  To test the effects of kiln-drying on strength properties of Douglas fir and western hemlock, temperatures to 230 F, conditions for equilibrium moisture contents of 6 percent and 12 percent, and prolonged ...

  Citation × Citation Citation Abstract Copy Title: Effect of kiln conditions on the strength of Douglas fir and western hemlock Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory To test the effects of kiln-drying on strength properties of Douglas fir and western hemlock, temperatures to 230 F, conditions for equilibrium moisture contents of 6 percent and 12 percent, and prolonged heating were investigated. Prolonged heating and choice of conditions for 6 percent or 12 percent equilibrium moisture content had little effect on most strength properties. Temperature was important: the higher the temperature, the greater the reduction in strength. Toughness was affected most, shear almost as much, modulus of rupture and fiber stress at the proportional limit somewhat less, and modulus of elasticity was affected least. Title: Effect of kiln conditions on the strength of Douglas fir and western hemlock Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory To test the effects of kiln-drying on strength properties of Douglas fir and western hemlock, temperatures to 230 F, conditions for equilibrium moisture contents of 6 percent and 12 percent, and prolonged heating were investigated. Prolonged heating and choice of conditions for 6 percent or 12 percent equilibrium moisture content had little effect on most strength properties. Temperature was important: the higher the temperature, the greater the reduction in strength. Toughness was affected most, shear almost as much, modulus of rupture and fiber stress at the proportional limit somewhat less, and modulus of elasticity was affected least. Close

• 2. [Article] Effect of kiln temperatures on strength of Douglas fir and western hemlock dimension lumber

  Citation × Citation Citation Abstract Copy Title: Effect of kiln temperatures on strength of Douglas fir and western hemlock dimension lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory Title: Effect of kiln temperatures on strength of Douglas fir and western hemlock dimension lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory Close

• 3. [Article] Drying Oregon white oak lumber

  Oregon white oak, Quercus garryana Dougl., could have greater commercial use, but information on its drying properties is lacking. All oaks are difficult to dry, and the initial kiln conditions are important ...

  Citation × Citation Citation Abstract Copy Title: Drying Oregon white oak lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory, Espenas, Leif D. Oregon white oak, Quercus garryana Dougl., could have greater commercial use, but information on its drying properties is lacking. All oaks are difficult to dry, and the initial kiln conditions are important to prevent excessive surface checking and honeycombing. This study illustrated that a maximum dry-bulb temperature of 110 F with a wet-bulb depression of 4 F is required to reduce checking and must be maintained until the average moisture content is 40 percent or lower. The second stage of drying required a dry-bulb temperature of 110 F with a depression of 6 F and is held until the average moisture content is 30 percent. The drying conditions are set to promote drying until the equalization period, which is a dry-bulb temperature of 180 F and a wet-bulb depression of 35 F. This is followed by a conditioning period, which is a dry-bulb temperature of 180 F with a wet-bulb depression of 10 F. Drying times ranged from 21 days for 4/4 (1-inch thick) lumber, to 32 days for 5/4 (1'44-inch thick) lumber, and 43 days for 6/4 (1 V2-inch thick) lumber. Air drying to an average moisture content of 15-20 percent will reduce kiln-drying time for 4/4 lumber from 4 to 5 days. Title: Drying Oregon white oak lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory, Espenas, Leif D. Oregon white oak, Quercus garryana Dougl., could have greater commercial use, but information on its drying properties is lacking. All oaks are difficult to dry, and the initial kiln conditions are important to prevent excessive surface checking and honeycombing. This study illustrated that a maximum dry-bulb temperature of 110 F with a wet-bulb depression of 4 F is required to reduce checking and must be maintained until the average moisture content is 40 percent or lower. The second stage of drying required a dry-bulb temperature of 110 F with a depression of 6 F and is held until the average moisture content is 30 percent. The drying conditions are set to promote drying until the equalization period, which is a dry-bulb temperature of 180 F and a wet-bulb depression of 35 F. This is followed by a conditioning period, which is a dry-bulb temperature of 180 F with a wet-bulb depression of 10 F. Drying times ranged from 21 days for 4/4 (1-inch thick) lumber, to 32 days for 5/4 (1'44-inch thick) lumber, and 43 days for 6/4 (1 V2-inch thick) lumber. Air drying to an average moisture content of 15-20 percent will reduce kiln-drying time for 4/4 lumber from 4 to 5 days. Close

• 4. [Article] High-temperature drying of Douglas fir dimension lumber

  Citation × Citation Citation Abstract Copy Title: High-temperature drying of Douglas fir dimension lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory Title: High-temperature drying of Douglas fir dimension lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory Close