There are 9 national standards for fiberboard in China, covering the fields of fiberboard production, product quality, packaging, transportation and storage. There are two general standards for medium density fiberboard, among which "Medium Density Fiberboard" (GB/T 1 17 18) is a general quality standard in the fiberboard industry, which has a high recognition.
Formaldehyde emission
Formaldehyde emission reflects the content of free formaldehyde in fiberboard, which is the only environmental protection index of fiberboard and also the quality index that the market is generally concerned about. During the use of fiberboard, the release of free formaldehyde beyond a certain limit will affect human health. The formaldehyde emission of fiberboard directly used indoors should reach E 1 grade (≤9mg/ 100g), and the formaldehyde emission of fiberboard used indoors should reach E2 (≤30mg/ 100g) after facing treatment.
The quality standard of fiberboard futures delivery follows the national standard system. The formaldehyde emission should meet the E 1 grade, and the allowable range should be ≤ 8 mg/ 100 g. At the same time, in order to ensure sufficient deliverable quantity, E2 grade is allowed to participate in delivery, but it is not encouraged to participate in futures delivery when the hedging premium is large and the price does not deviate greatly. Adopting strict standards conforms to the positioning of fiberboard futures in furniture plates, which is forward-looking, represents the future development trend of the industry and is in line with international standards.
(2) Other main inspection indexes
The main index of fiberboard inspection is in addition to formaldehyde release, as well as appearance index and physical and chemical index. The index differences of different types of MDF are mainly reflected in physical and mechanical properties, including water absorption thickness expansion rate, static bending strength, elastic modulus, surface bonding strength and internal bonding strength. In terms of static bending strength and elastic modulus, load-bearing board >: furniture board > ordinary, and furniture board has increased the surface bonding strength index.
Second, the current national standards and inspection indicators of plywood
In plywood production, machine splicing has become the development direction of the industry. The transaction target GB/T5849 is widely implemented in the industry with a high degree of standardization.
Formaldehyde emission
The formaldehyde emission of indoor boards can be divided into three grades: E0, E 1 and E2. E0 grade ≤ 0.5mg/L, E 1 ≤ 1.5 mg/L, E2 ≤ 5mg/L ... The quality standard of plywood futures delivery follows the national standard system, and the formaldehyde emission should reach the grade of E1,with the allowable range ≤1.5mg/. Similarly, the E2 level is given a large discount, and participation in delivery is generally discouraged.
(2) Other inspection indexes mainly include appearance, specification, moisture content, transverse static bending strength, immersion peeling performance, surface adhesion and strength. (Second field knowledge of fiberboard and plywood)