Abstract: A method of producing a strand board having an average density of between 450 and 550 Km/m3 by providing a first set of strands having a moisture content of between 25 and 45% based on the dry weight of said strands and a second set of strand having a moisture content of between 5 and 7% based on the dry weight of said strands and forming a lay-up having a core layer formed of strands from the second set of strands sandwiched between a pair of surfaces layers each formed from strands of the first set. The lay-up is then pressed between heated platens into a consolidated panel having an average density of between 450 and 550 Km/m3 by closing the platens to the thickness of said consolidated panel in less than 30 seconds and raising temperature the said core layer to 100° C. in less than 35 seconds without increasing the core gas pressure above 0.17 MPa.
Abstract: A method of producing a strand board having an average density of between 450 and 550 Km/m3 by providing a first set of strands having a moisture content of between 25 and 45% based on the dry weight of said strands and a second set of strand having a moisture content of between 5 and 7% based on the dry weight of said strands and forming a lay-up having a core layer formed of strands from the second set of strands sandwiched between a pair of surfaces layers each formed from strands of the first set. The lay-up is then pressed between heated platens into a consolidated panel having an average density of between 450 and 550 Km/m3 by closing the platens to the thickness of said consolidated panel in less than 30 seconds and raising temperature the said core layer to 100° C. in less than 35 seconds without increasing the core gas pressure above 0.17 Mpa.
Abstract: The present invention is concerned with a method for obtaining a wood panel, preferably an OSB panel, with significantly reduced thickness swelling properties when exposed to or contacted with moisture or water. The novel dimensionally stable panels are obtained by an alternate vacuum—steam injection method. The method is an after-fabrication, or post-treatment method, and involves one or more cycles of applying a vacuum followed by injection of hot steam in a sealed treatment chamber.
Type:
Grant
Filed:
May 4, 2000
Date of Patent:
December 25, 2001
Assignee:
Nexfor Inc.
Inventors:
Andrew Go, Wallace S. Pettersen, Alain Laplante