Fir Product Timber Manufacturing In The Combing Process And Product Characteristics

In order to explore new approaches for high efficient processing and utilization of Chinese fir resources, the author has developed a new type of composite board—Chinese fir Oriented Laminated Stick Lumber (CFOLSL) using sawmill slabs of Chinese fir as the basic material. The combing process and product characteristics of CFOLSL were systematically studied. The main results of the research are as follow:(1) The concept of wood combing processing was put forward the first time, internationally as well as domestically. The macroscopic theory, microcosmic mechanism of the Chinese fir combing processing were discussed systematically. It is found that the theory system of Chinese fir combing processing.(2) Based on the theories of combing processing Chinese fir, prototypes of small combing machine for laboratory use and large combing machine for factory production were designed and manufactured for the first time at home and abroad. A production line of CFOLSL are found. Results of laboratory experiments and factory production trials show that combing processing theories, technologies and so on are correct and practical and feasible in the manufacture of CFOLSL.(3) The combing process is made up of no-cutting, radial rolling and pressing, and longitudinal no-chip cutting (similar to combing hair with a wood comb). Owing to the unique characteristic of the combing process, the organizational structure of the wood sticks is largely intact and the strength is basically kept. Moreover, the energy consumption is low, and the production efficiency and the wood utilization rate are high.(4) During the hot pressing, the influence of wood stick's shape, moisture content on heat transfer is only a few. The panel density, thickness, platen temperature and pressure have greater influences on heat transfer. The length, width , oriented angle and resin content of the wood sticks, hot pressing temperature, hot pressing time, and so on have greater influences on physics and mechanical properties of CFOLSL.(5) For the first time, the vertical and horizontal density distributions were systematically analyzed using both destructive and non-destructive techniques, including sawing, CT (Computed Tomography), Dense-Lab X testing. The results show that: the surface layer of CFOLSL is characterized by stick-shaped structure. The CT can better reveal vividly and intuitively the characteristics of density distribution.