1. Stick panel warping: There are many reasons for the warpage of the veneer, mainly:
(1) The base paper impregnation is not uniform, with different volatile matter.
(2) Thermal pressure without thickness gauge;
(3) The temperature difference between the top hot pressing plate and the bottom hot pressing plate is too large, so that the curing speed on both sides of the paste panel is inconsistent, resulting in the plate bending towards the fast curing side.
(1) Adjust the base paper impregnation speed, according to the requirements of modulation impregnation resin;
(2) Increase the thermal pressure thickness gauge, control the compression thickness;
(3) Adjust the temperature difference between the upper and lower pressure plate, so that the difference does not exceed 4 degrees Celsius
2. Adhesion of polishing board: some of the melamine resin adheres to the polishing board during the curing process, resulting in the surface cracking of the laminate. The reasons are as follows:
(1) Curing time is too long or too high temperature;
(2) Melamine resin in the absence of mold release agent;
(3) The quality of the polishing board dropped.
The above shortcomings can be overcome by adjusting the temperature of hot pressing, demodulating when adding stripping agent, in addition to a better polishing plate, such as chrome plating polishing plate.
3. Paste panel surface porous: the board surface porous mainly due to resin at high temperature or low pressure flow exhibition is not sufficient, in addition, particle board surface structure also has a certain impact on paste panel, therefore, can increase the pressure to the maximum, increase the volatile content of paper and resin content; Increase the modifier content by 0.5%. In addition, check whether the impregnated paper is stored too long or improperly.
4. Laminating and bubbling of the laminating panel, the laminating of the laminating panel mainly includes the following aspects:
(1) Resin waterproof paraffin, oil or paraffin coating film on the particleboard surface;
(2) Impregnation paper resin content is very small, resin mobility is too low, so that the particleboard surface resin is insufficient;
(3) Particleboard moisture content is too low or impregnated paper volatile content is too low.
The cause of cloth bubbling is due to the substrate is too thin or moisture content is too high in the veneer time water vapor, when the press opened, causing blisters.
5. When the edge of the board is cut, the edge of the board is damaged due to the tear of the wood chip, etc., and the causes of defects may be: insufficient strength of the base material edge; The shear strength of the base material surface is not enough, or the shape of the cutter, the sawtooth needs to be adjusted, the sawing speed is too low or the feed speed of the plate is too fast is also one of the reasons. Therefore, in addition to the purchase of high-quality base materials, to check the tool regularly.
6. Dip paper folding during hot pressing: there are many reasons for dip paper folding during hot pressing. The following measures are generally adopted to overcome:
(1) Slow down the closing speed of the press;
(2) Check whether the polishing plate of the compression strip warping or polishing plate need to be updated;
(3) Check the electrostatic device and clean or transform the power supply;
(4) Check the storage room of the impregnated paper in the atmosphere and wet paper rigidity.
7. Impregnation in the drying box paper fold: measures taken are:
(1) Relax the friction brake on the relaxing device to reduce the tension of the paper;
(2) Reduce the paper in the active roller and driven roller tension;
(3) The base paper through the first dip tank after the release of the drive scraper.
8. Surface water trace (wet flowers) cause:
(1) The substrate moisture content is too high;
(2) impregnation paper moisture content measuring instrument installation is not good; (3) impregnated paper residual volatiles too much;
(4) Stick panel edge temperature is too low and impregnation paper moisture back when storage, take measures are:
(1) Adjust the substrate moisture content;
(2) Adjust the moisture content meter;
(3) Adjust the impregnation paper drying process conditions;
(4) To increase the temperature of the hot platen namely improve 5 ℃, in addition, pay attention to the safekeeping of impregnated paper.
9. Emulsion spot this type of defect mainly occurs in the hot press color plate, the main reasons are:
(1) the pressure is too low;
(2) the substrate thickness tolerance is large; The polishing board is polluted. Take measures mainly have:
1. (2) adjust the amount of substrate sand or improve the thickness of the substrate requirements; (3) brush polishing board or replacement.
In short, melamine resin impregnated veneer wood-based panel production process of the defects are constantly found, find out the reasons to overcome, as long as we strictly in accordance with the process requirements, put a good quality inspection, we will be able to produce more and better products, improve the economic benefits of enterprises.