Technical parameters of Laminated Veneer Lumber manufactured with dyeing and fire-retardant treated veneers

The technologies of veneer dyeing,fire-retardation and gluing were studied using an orthogonal test design. The properties of gluing Laminated Veneer Lumber(LVL) product were tested and reasonable technical parameters were determined. The results show that:1) It is feasible to apply the techniques of wood dyeing and fire-retardant simultaneously. 2) the concentration of fire-retardant is positively correlated with the oxygen index and negatively correlated with shear strength,the modulus of rupture (MOR) and the modulus of elasticity (MOE) of the products;other factors have some effects on the quality of LVL to some degree. 3) the optimal technical parameters are as follows:dyeing concentration 0.3%, fire retardant concentration 15%,hot press time 50 s, temperature 150℃ and compression rate 20%.