Wood-fiber board
Wood-fiber boards (abbreviation WFB) of general-purpose produced by the wet method are a sheet material manufactured in process of hot pressing of wood fiber mass, which is formed as a carpet. These fibers are obtained by steaming and milling of wood raw material.
Raw materials are waste of lumbering and woodworking, pulpchips and fuelwood for technological needs. The phenol-formaldehyde resins and paraffin are used to increase strength of the WFB.
Commercial production of WFB began in the USA in 1922. In 1931 the Swedish patent was obtained on introduction of a new technology, which is most widely spread in the world, the main technological stages remain unchanged until now: wood raw material is milled to the state of wet cotton-like mass, under relative humidity of 60-70% it is fed to pressing. According to their intended use the boards are divided into types: hard (T, quality group A or B) and soft (-3).
At present the Open JSC Nelidovskiy DOK produces hard wood-fiber boards (WFB) State Standard 4598-86 of the following types and sizes: :
grade T quality group A
density from 850 to 1100kg/m
thickness 3.2mm; 4.0 mm
width 1220 mm
length of sheets from 1740 to 3050 mm (according to customers order)

Due to increased strength and water resistance the hard WFB is indispensable for furniture production; it is also widely used in construction.

An example of reference designation of a hard board of quality group A, sort 1, nominal dimensions 305012203,2 mm: T gr. A I s 305012203.2   State Standard 4598-86