First, the hot pressing method has the advantages of high production efficiency and good product bonding quality. Domestic and foreign manufacturing blockboards mainly use hot pressing method.
For example, the urea-formaldehyde resin blockboard is manufactured, the unit pressure is 0.6-1.2 MPa, and the hot-pressing temperature is 100-120 degrees Celsius. The hot pressing time depends on the thickness and structure of the slab. For the part of the veneer covering material in the slab, the hot pressing time is 50-60 seconds per 1 mm plate thickness, and for the core plate, the thickness of each 6 mm plate is required to be hot pressed for 1 minute, and the plate having a thickness of 19 mm is generally required. About 7-11 minutes.
When producing phenolic resin bakelite board, it adopts higher hot pressing temperature and higher unit pressure than urea-formaldehyde resin glue, and adopts hot pressing temperature of 125-145 degrees Celsius, pressure of 1.0-1.2 MPa, and thickness of 19 mm. About 11 minutes.
In the production of blockboard, in order to improve the output and quality, there has been a trend of using low temperature and low pressure in recent years. The lower the hot pressing temperature, the smaller the internal stress of the slab, the higher the flatness of the sheet, the lower the pressure, the smaller the compressibility of the slab, the smaller the deformation of the sheet after hot pressing, and the less warpage and unevenness of the sheet surface.
Second, the cold pressing method has the advantages that the internal stress of the finished product is small, the deformation is small, and the compression loss of the wood is small, and the disadvantage is that the production cycle is long.
When cold-pressed and glued, the plasticity of the wood and the adhesiveness of the adhesive are poor, and a relatively high unit pressure is required. When the urea-formaldehyde resin is cold-pressed and glued, the unit pressure is 1.2 MPa, and the bonding time is 6-8 hours.
The slab adopts a pile of cold pressing, and a pad is required at a certain height to make the slab evenly stressed to ensure that the plate surface is flat.
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SAMINA FORAM(SHENZHEN) CO.LTDwas established in 1976 and in 1991, we moved from Korea to Shenzhen, China. At that time, our company had about 200 technicians who were our most valuable assets. For us, each employee is an important part of our road to success, and their skills and experience are critical to the development of our company. Our business philosophy is to inspect all products 100%. This means that we carry out meticulous quality checks on each and every product to ensure that the quality of the product meets the needs and expectations of our customers. We are convinced that only through our unremitting efforts and strict quality standards can we gain a competitive edge in the market and win the trust of our customers.
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