METHOD OF MANUFACTURING VENEER LAMINATED LUMBER(VLL)- AN ECO FRIENDLY WOOD COMPOSITE PRODUCT

摘要

. According to this invention, different sizes in length, width and thickness of sawn timber of Agro forestry plantation species after removing all the timber defects such as knots, pith, bark etc., are kept ready for next operation. BAE (Boric Acid Equalent) solution of boron compounds and preservative chemicals are impregnated to the sawn timber by using the full cell method (vacuum pressure method). Chemical impregnated sawn timber is subjected to kiln dryer to bring down the moisture content in the desired range of 8% to 10% Seasoned sawn timber are subjected to various mechanical process to get the required size for the construction of composite boards. Shorter lengths of processed timber are subjected to the finger jointing and edge lamination technique to get the long pieces and the wider board respectively - See Fig- 1. Same plantations species veneers are used for cross bonding glue core and thin thickness of face veneers are used at the top and bottom of finger jointed edge laminated boards as per the normal 5 ply board - See Fig - 2. Similarly the 5 ply construction can be made with top and bottom layers using the finger jointed and edge laminated boards and the middle cross -band core is of three layers of wood veneers to give wooden lacing on both sides - See Fig - 3. Synthetic phenol formaldehyde or amino resins used for throughout the process for bonding of wood and veneers. Boards are subjected to the temperature in the range of 110° C to 150°C and the specific pressure in the range of 10 kg/cm2 to 20 kg/cm2 in a hydraulic hot press for the desired time according to the thickness of the boards. The hot pressed boards are stacked over night to release the stress and strain from boards. Further trimming and sanding is required for the finish product. Finally these boards are resized in the desired dimension and profiles according to the end applications, mainly to produce door, window, ventilator frames and shutters.