Des visites industrielles auprès des producteurs et des utilisateurs de panneaux collés sur chant ont été effectuées afin de définir ce qu’est un collage sur chant de qualité pour les produits d’apparence. Cette enquête répondait ainsi au premier objectif spécifique du projet. Lors des visites, des panneaux collés avec joints de bonne et de mauvaise qualité ont été recueillis pour examen au laboratoire de Forintek. Des mesures effectuées au microscope ont permis d’établir à 0.05 mm la valeur maximale acceptable de largeur du joint de colle d’un panneau. Les principales causes de joints problématiques propres à l’opération de délignage des bandes sont l’éclatement des fibres du bois sur l’arête, la trop grande rugosité de la surface sur chant et la mauvaise rectitude du trait de scie. La proportion de panneaux rejetés reliés à ces causes varie de 0.5 à 3 %. Les fentes en bouts et les joints ouverts aux extrémités dus à un retrait en largeur des bandes de bois suite à un séchage sont responsables d’une plus grande proportion de rejets de panneaux.
La plupart des usines visitées utilisent une scie à refendre à lame unique pour le délignage de bandes de largeur variable. Les modèles de déligneuse Mattison 202 et 404 sont utilisés dans la majorité des cas. Toutefois, certaines usines utilisent des modèles à scies multiples. Suite au délignage, la qualité du trait de scie est vérifiée de façon visuelle seulement. La présence de la pointe de diamant sur chant est utilisée comme indice de qualité collage. La seconde année du projet portera sur l’identification et le développement de méthodes d’évaluation des paramètres affectant la qualité collage.
This project evaluates the potential for non-structural panels in the furniture (including cabinetry) and interior finish industries in China. It entailed two stages:
1. Review of existing information on non-structural panel markets and industry in China;
2. Survey of wood-based panel manufacturers and non-structural panel specifiers in China.
137 furniture and 132 interior finish manufacturers in eastern and southern China were surveyed by phone, mail/fax, and in personal interviews. Personal interviews were carried out with 11 panel mills in the eastern region.
The literature review is based on the Preliminary Competitor Analysis for Wood Products in China (Wahl and Gaston, 2003) that was carried out for Forestry Innovation Investment. Information specific to furniture, other non-structural panel markets and more recent publications have been added to this literature review.
This report summarizes the work and findings of a national research project designed to investigate both the process parameters that affect resin application efficiency and the possibilities for optimizing MDF resin injection systems.
The scope of this research includes: developing and evaluating methods to quantify resin distribution, degree of resin pre-cure, and resin loss; conducting a series of experimental works using selected test methods to quantify the resin distribution of blowline-blended fibre, resin loss, resin pre-cure, and their correlations to MDF panel properties.
Based on experiment results, the following conclusions can be reached:
Blowline resin injection is still the most effective and economical method for resin blending in MDF production.
Blowline resin blending efficiency is affected by fibre characteristics, resin distribution, resin pre-cure, and resin loss during the MDF process.
Resin distribution is affected by steam/fibre flow dynamics and consistency, and resin spray characteristics.
The best resin distribution can be achieved with steady steam/fibre flow at an adequate velocity (approx. 80 m/s at the injection point with steam pressure of 4.5 bar) and high turbulence in the blowline, low resin viscosity, and a good injection nozzle system.
Both the XRF test method developed by Forintek and the nitrogen content test using the Kjeldahl method are effective methods for determining resin content and resin distribution on the MDF fibre.
For the typical MDF mill studied, resin loss during the MDF process is about 6.5%.
Overall resin pre-cure in a typical MDF process is about 20%. Results from the laboratory experiment confirm that at 40ºC, the rate and magnitude of resin curing reaction can be significant.
The test methods developed or adopted in this study for analyzing resin distribution, resin loss, and resin pre-cure, and the computer model for calculating refining energy balance can be effective tools for optimizing blowline resin injection systems in MDF mills.
One of Forintek’s most valued services to the oriented strandboard (OSB) members is our use of computer modeling tools to assist members optimize their manufacturing processes and quantify the potential benefits of new technology developments This project substantially upgraded our hot pressing model and added two new models to Forintek’s suite of modeling tools.
Forintek’s 2-D hot pressing model describes the relationship between hot pressing schedules and panel attributes. In this project the 2-D hot pressing model was upgraded to a 3-D model. The 3-D model improves the prediction accuracy of heat and moisture transfer and vertical density profile during the hot pressing process. The model can be used to quantify the costs of current hot pressing processes and predict the potential cost implications of changes to schedules and equipment. It can also be used to assess the need for, and impacts, of developing new pressing technology.
Two new models were developed: one for continuous pressing and one that predicts the mechanical properties of panels from specific manufacturing options. Continuous pressing is an emerging technology which is increasingly used by the composite board industry. This project marks the completion of our first model for continuous pressing. The model simulates the distributions of temperature, moisture content, gas pressure and density profile along the press during pressing based on input data that describe panel structure, layer structure, flake geometry and pressing schedule. While the modelling tool provides many insights into the continuous pressing operation, some basic laboratory tests and mill trials are still needed to optimize individual members’ pressing operations.
The first model to predict the mechanical properties of OSB end products from manufacturing process attributes has been completed. The model predicts end product panel modulus of elasticity (MOE) from density profile, flake geometry, strand orientation, fines content and layer structure.
The models completed in this project will be used as a guide for research and development of new products and process optimization for existing products. Use of these models results in significant savings in R&D costs and higher efficiency in problem solving for members.
A survey of coatings manufacturers was conducted throughout North America with a view to identifying which companies were engaged in the production of products recommended or potentially suitable for application to exterior and interior wooden substrates with particular emphasis on Engineered Wood Products for exterior exposure. Suitable companies were asked to complete a questionnaire