Sampling of artificial boards in the most problematic five indicators

?Surface resistance to cigarette burn

?static flexural strength

?internal bonding strength

?water-absorbing thickness expansion

?impregnation peeling

Do you know what they all mean?

Let me go over what they stand for:

First, the surface resistance to cigarette burning is the main quality indicators of all kinds of impregnated film paper veneer panel, to examine the product surface to withstand cigarette burning ability. To a certain extent reflects the flame retardant properties of the product surface.

GB/T 34722-2017 "Impregnated Film Paper Finished Plywood and Blockboard" and GB/T15102-2017 "Impregnated Film Paper Finished Fiberboard and Particleboard" require that the surface resistance to cigarette burns should be at least level 4. (Chinese Standard)

That is, at a certain angle to see the luster has a slight and/or brown spots, surface resistance to cigarette burning reflects the flame retardant properties of the product, poor resistance to cigarette burning performance of impregnated film paper veneer panel. Its surface resistance to ignition cigarette burning is relatively weak. Impregnated film paper meet cigarette burning at high temperatures, the surface is prone to brown spots, cracks, bubbles, affecting the beauty and use of the plate. In serious cases, it may even cause a fire.

Second, the static bending strength is the main quality indicator of all kinds of impregnated film paper veneer panel.

Examination of the product bending bearing force and resistance to force deformation ability. Board static bending strength and thickness, usually the thickness of the board's static bending strength value is low. Failure of static bending strength, indicating that the mechanical properties of the product is poor, in use can not withstand the pressure that should be borne, often cracking or fracture, affecting the safe use of the product and life.

Third, the internal bond strength is the main quality index of impregnated film paper veneer medium density fiberboard and particleboard.

Reflects its processing and use of function and plate internal fiber or particle combination ability.GB/T15102-2017 in different thickness of the board's index requirements are also different. The greater the thickness of the plate, the lower the internal bond strength requirements. Unqualified internal bonding strength can easily lead to loosening and delamination in the use of the product, affecting the use of function and aesthetics.

Fourth, the water-absorbing thickness expansion rate is the main quality index of impregnated film paper veneer fiberboard and particleboard.

Examine the substrate fiberboard and particleboard water resistance and dimensional stability after water absorption.GB/T 15102-2017 in accordance with the type of substrate, the thickness and density of the board, the board's water-absorbing thickness expansion rate is stipulated. The water-absorbing thickness expansion rate is not each product is easy to swell in the moisture, easy to crack by external force, reducing the service life of the product.

Fifth, impregnation peeling is the main quality indicator of impregnated film paper veneer blockboard.

Examine the impregnated film paper veneer blockboard in wet conditions of the gluing quality. gb/t 34722-2017 specimens on each side of each glue layer peeling length can not exceed 1/3 of the side length. impregnation peeling unqualified, the product in the moisture will cause the glue layer open, delamination, affecting the use of the product.

So what are the reasons for failing these indicators?

There are three main reasons:

First, some enterprises have a weak sense of quality, the technical level of enterprise personnel and quality awareness affects the quality of impregnated film paper veneer panel products.

Enterprise production personnel should systematically learn the relevant production knowledge, understanding of wood-based panel standards, to ensure that the production of panels in line with requirements.

Second, the production process is unreasonable. Product failure, but also closely related to the production process.

The main reason for the surface resistance to cigarette burning failure is the production process of decorative panels hot pressing pressure, temperature and time do not meet the requirements, resulting in hot pressing process of resin spreading and curing is not good. Can not completely cover the surface of the panel. Can not form a sealed uniform resin layer on the surface to protect the surface of the panel from cigarette burns.

The main reasons for unqualified static bending strength: (1) insufficient glue application or uneven distribution of adhesive; (2) high moisture content of the slab; hot pressing time is too short, hot pressing temperature is not enough, resulting in incomplete curing of the adhesive layer, not the formation of curing layer

The main reasons for unqualified internal bonding strength: (1) insufficient glue application; (2) too fast pressurization (product density gradient is too large) and insufficient hot pressing time, high moisture content inside the slab, low temperature, the adhesive is not fully cured; (3) unreasonable thermal post-treatment, insufficient cooling time of the board. Stacking temperature is too high, excessive curing degradation of adhesives

The main reasons for the unqualified rate of expansion of water-absorbing thickness: (1) the amount of glue is not enough or the adhesive is not fully cured; (2) paraffin wax is not enough to apply the amount or distribution is not uniform.

The main reasons for unqualified impregnation peeling:. (1) The moisture content of core strip, center board and surface board is not controlled; (2) The use of modified urea-formaldehyde adhesive with low solid content; (3) The hot pressing temperature, hot pressing pressure and hot pressing time are not controlled; (4) The use of modified urea-formaldehyde adhesive with low solid content is not controlled.

(3) Hot pressing temperature, hot pressing pressure, hot pressing time is not controlled.

Third, enterprise management is not in place. Many wood-based panel companies have not set up a specialized laboratory to control product quality.

The quality of raw materials is not strict, such as fiber grinding too fine or coarse, fiber or particle density is low, particle or fiber form or poor quality; recycled materials accounted for a larger proportion; the use of low-quality impregnated film paper. The content of solid resin in the film paper is not enough. Factory inspection in form or even no inspection.

#construction?#market #product #plywood #lvl #osb #timber #lvl

#Wood #furnture #industry #technology #mdf #cabinets #Ijoist

#Constructionmaterial #Leader #packing #osbboard #mdo #hdo