What is wood heat treatment and why is it so important? The question could arise in those who do not fully know the qualities of this material so “alive” and therefore subject to the attack of pathogenic agents. The natural raw material par excellence, which fascinates us with its elegant and refined veins, has physical properties that make it particularly attractive to pathogens. The high percentage of water present in the freshly cut trunks, combined with the sugars contained in the cells and with oxygen, are in fact the three elements that attract insects and lignivorous fungi, whose presence could cause devastating effects in a piece of furniture, a parquet floor or a wooden shelf. By eliminating even just one of these elements, we would have practically eliminated the risk of attacks. But how to do it? Many use chemicals based on boron salts, creosote and copper sulphates, certainly effective but also harmful to humans. A method to guarantee unassailable wooden artifacts without the use of chemicals is given by heat treatment.
How the Vacuum Heat Treatment of Wood Takes Place
It is a completely natural process performed inside special bivalent cells capable of carrying out drying and treatment at high temperatures. The wood is first dried bringing the humidity level almost to zero. At this point the actual heat treatment takes place, creating environments with temperatures between 190 and 210 degrees. The chosen temperature level must take into account the final destination of the wooden products: if a 190 degree heat treatment is useful for wood to be used for home furniture, one at 210 degrees will be perfect for obtaining boards to be used for garden furniture and outdoor spaces. Once the desired temperature has been reached, it remains constant for 2/3 hours, before proceeding with cooling. In this phase the high heat could generate fires and it is for this reason that the chambers in which the treatment is carried out at high temperatures involve vacuum processes, i.e. in the absence of oxygen. Together with the cooling, a percentage of humidity of about 8% is returned to the wood through the steam, in order to make it workable later.
WDE Maspell is an italian brand which has been designing and manufacturing wood treatment machinery for over sixty years. Experience, competence and professionalism make it a point of reference for many companies operating in the sector.