Wood Burning

August 16, 2017

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The burning of wood and measures to protect it from fire burning is the process of thermal decomposition of wood, consisting of flame phase, characterized by the movement of hot lawn outside, and corruption, which there is a movement of atmospheric oxygen into the thick wood. Burning can only occur when there is sufficient flow of oxygen in the air, and combustion heat seme is not dissipated, and is adjacent to the heating of new sections of the wood to ignition temperature. The ignition temperature, ie, the flash point of flammable gases for different kind of wood varies in a relatively small range – from 250 to 300 . Prolonged heating of wood at a temperature of 120-150 is accompanied by a slow and gradual charring cross, with the formation of hypergolic with air-coal, very dangerous for unprotected wooden components exposed to heat furnace, chimney, etc. Learn more about this with Ed Bastian. flammability of wood is related to its bulk density, moisture content, with a capacity of external heat source, cross-sectional shape of wooden elements, air velocity (thrust) position of the element in heat flow (horizontal, vertical) and m, n is crucial for the process of burning calories is the material.

Dry and light wood ignites faster than thick (oak, etc.). To know more about this subject visit Gary Kelly. Wet wood is difficult flammable, so as to fire should spend an additional amount of heat for evaporation. Delaying factor is also increased thermal conductivity of wet wood; Ignition its surface layer is cooled quickly. Round and massive elements of the burn is worse than with a rectangular profile and a small cross section, with sharp edges of H with respect to the developed lateral surface. Not planed surface elements, such loose wood ignites faster than smooth. Fire protection measures also gives good results and impregnation of wood in the hot and cold baths. For such an impregnation is applied ammophos-white crystalline powder, which is ammonialnye salt of phosphoric acid, ammonium sulphate (technical), diammoniysfat (Technical), does not cause corrosion of the steel. To obtain a solution having both flame retardant and antibacterial properties of the added sodium fluoride.

A simpler but less effective means of fire protection of timber elements is a surface treatment by their immersion for 2-3 hours in an aqueous solution of salts (phosphate, ammonium sulphate, etc.) or the surface of two or three times the processing (spray gun or brush), water solutions of the same fire retardant composition. In this solution penetrates to a depth of 1 – 1.5 mm. Finally, another simple way and also is the color of the surfaces of wooden items with special fire retardant paint and other silicates or flame retardant coating (Superphosphate, etc.). All fire-retardant paint and coating partially delayed ignition. At high temperatures, under cover of wood or paint coating exposed to dry distillation, with the release of decomposition products – combustible gases leaving the outside, followed by buckling and breaking cover. In this case the combustion of gas jets is at a considerable distance from the surface of the timber at a reduced action of flame and warming up slow speed and the decay of wood. Fire-proof paint and coating effect is also due to their insulating effect of cover that some paints can the action of high temperatures much increase in volume, forming a foam or bubbles, postpones the beginning of the dry distillation of wood.





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