In order to expand the scope of the use of artificial board and improve the use value, it is necessary to decorate the surface. The use of melamine impregnated paper for the medium density fiber board and particle board for veneer with less materials, low energy consumption, less working process, low cost, beautiful appearance and so on. The quality problems often appear in the production process are analyzed as follows. Production process quality control One Production process Decorative melamine resin impregnated paper medium density fiber board (OSB) production process is as follows: substrate preparation, plate surface dust, billet; hot pressing; trimming, inspection, warehousing. Two Substrate quality control Production should often check density fiberboard substrate and impregnated paper quality and technology indicators qualified rear can feed production. Paper quality and impregnation process In order to ensure the quality of impregnated paper, must try high quality decorative base paper. No matter what kind of paper should be inspected and qualified to use, not qualified to enter the production line. In the impregnation process, should be strictly in accordance with the requirements of the process, each 39min sampling inspection time, ensure the technical requirements of the glue quantity for 130%~150%, volatile content of 6-7 per cent, stubborn degree less than or equal to 65%; impregnation and drying glue film paper immediately packed in a plastic film and adhesive strips of adhesive closure. Stored in a temperature of 25 DEG C, 55% - 65% humidity, installed air conditioning storehouse, a use could not finish the paper should be immediately sealed and sent to the warehouse and storage, to prevent moisture absorption leads to adhesive paper bonded together and can not be used, resulting in unnecessary economic losses. In addition, the impregnated paper mobile process should avoid breakage; group of billet in the process such as the discovery of surface is not clean to clean up in time; when the feed to carefully check the substrate. Substrate requirements for faced plywood Substrate requirements for faced plywood Commonly used medium density fiberboard and particleboard should according to the different requirements of customers purchased, but particleboard products must meet the needs GB/T4897-92 first-class. 1) flat plate surface cleaning, water stains, oil stains are not allowed. Not in size, while taking gnawing head defects eng; 2) the thickness of the plate should not exceed the 0.2mm + +, and the sand light is uniform, not to allow leakage of sand defects; 3) the water content of the plate should be controlled in the range of 6%~10%. Because particleboard is purchased, the change of the environment may cause changes in the moisture content of the. If the moisture content is low, or dipping paper volatile content is low, hot pressing may produce a layer of cardboard phenomenon. Therefore, in the production process need to be observed at any time, in a timely manner to remove unqualified substrate. Embrios Substrate after the after entering the assembly process, the blank group operations to ensure impregnated paper full coverage on the surface of the substrate and ensure the coincidence of the center line of the slab and the central line of the compressor, to ensure that the slab enters the press after the accurate position and avoid template pollution caused due to the shifting of the slab. Quality control of hot press process Three factors (hot pressing temperature, hot pressing pressure, hot pressing time) are interdependent and mutually restricted, which need to be analyzed and adjusted in the process of process adjustment. The effect of the three factors on the paste panel is different, the hot pressing temperature is mainly on the chemical reaction of the resin impregnation, that is, accelerated curing. According to the actual production requirements and experience, the temperature of the hot pressing plate to 170 degrees C~200 degrees C, panel unit pressure for 2.0~3.0MPa, hot pressing time for 25~50s, hot pressing curve for a pressurized more appropriate. Appropriate temperature and time according to the color and quality of paper, deep color paper to the low temperature, long process time and temperature is generally for 170 degrees C~180 DEG C, holding more than 40s; light colored paper should adopt high pressure, short process time. You should also check the appearance quality of decorative panels, prevent paper scraps, insects, fingerprints and other surface pollution. Suitable hot pressing pressure can guarantee between the substrate and the impregnated paper good combination under suitable temperature and pressure, impregnated paper in the molten resin after curing, can form a closed and compact surface and the substrate surface of tiny pores can be filled. Usually under the premise of not affecting the quality of the products, should as far as possible the use of low pressure, so the inner structure of the life-span of equipment, hydraulic oil, substrate are favorable, but the pressure is too low will influence on the substrate and impregnated paper of the bond strength of resin and flow capacity. Therefore, in actual production, the new and old degree of different base materials and cushion pad should be adjusted to adjust the unit pressure of the hot pressing plate properly. Product quality control Product quality control according to GB/T12102-94 "impregnated film paper veneer artificial board" standard in the implementation of the quality indicators.
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