What is the production process of bamboo plywood?
The large diameter bamboo is cut into bamboo segments, milling and then divided into 2 to 4 blocks, then milling the inner segment for cooking and softening, then heating and pressing on the upper pressure single layer press machine to unfold the arc-shaped bamboo block into a plane. Finally, after processing the double-sided planer, the thick without bamboo green bamboo bamboo.
By using the manual blank, the blank is strictly divided according to the symmetrical principle, odd layer principle and the vertical texture of the adjacent layer bamboo. Bamboo panels are required to be made of good material, and bamboo pieces with lower material are used as backboard. Face and back of the bamboo chips outward oriented in core plate group tabasheer; blank, is toward the adjacent bamboo sheet are orderly arranged according to the bamboo chips, bamboo yellow alternate.
The four roller coating machine soluble phenolic resin on bamboo roller coating glue water, the quantity is 300, 350g/ square meters (double). Adhesive can be added 1%--3% flour, soy flour and other fillers. The filling agent causes the bamboo sheet to form a gum film on the surface after gluing, which is difficult to produce flowing glue when hot pressing, and the brittleness of the adhesive layer can be improved after curing.
In order to prevent the bamboo in the drying process, curl deformation makes the flat bamboo recovery force on the transverse elastic, compression technology and equipment must be used dry, wet bamboo is heated under pressure in pressure relief, out of the water and free shrinkage.
Pre pressure in order to prevent slab displacement is generated to heat press plate when caused by laminated core, seam defects before the blank after hot pressing, to slab preloading at room temperature, the material is glued into a whole.The hot pressing using heat bonding technology, the hot pressing temperature is about 140oC, the unit pressure is 2.5 3.0MPa, hot pressing time is calculated according to the sheet thickness, usually 1.1min/mm.In order to prevent the "bubbling" phenomenon, the three stage depressurization process is usually adopted in the later stage of hot pressing. The first paragraph from the work pressure down to "balance pressure", the second paragraph from "balance pressure" down to zero, the third section from zero to hot plate completed the opening.
