Classification :: DOK Kalevala

Classification.

There are four types of boards, defined in terms of the fields of use and physical and mechanical properties:

OSB-1 - Non load-bearing boards, general purpose boards and boards for interior fitments for use in dry conditions.

OSB-2 - Load-bearing boards for use in dry conditions.

OSB-3 - Load-bearing boards for use in humid conditions.

OSB-4 - Heavy-duty load-bearing boards for use in humid conditions.

Physical and mechanical properties of OSB-3 Kalevala

Load-bearing boards for use in humid conditions within physical and mechanical properties shall comply with the requirements specified in the table as follows:

The measurements are carried out in compliance with GOST (State Standard) methods.

Property	Requirement for board thickness range (mm, nominal)
Property	6 to 10 incl.	11 to 17 incl.	18 to 25 incl.	26 to 31 incl.	32 to 40 incl.
Bending strength - major axis of board, MPa, not less	22	20	18	16	14
Bending strength - minor axis of board, MPa, not less	11	10	9	8	7
Modulus of elasticity in bending - major axis of board, MPa, not less	3500	3500	3500	3500	3500
Modulus of bending elasticity - minor axis of board, MPa, not less	1400	1400	1400	1400	1400
Tensile strength perpendicular to the plane of board, MPa, not less	0,34	0,32	0,30	0,29	0,26
Swelling in thickness for 24 h., not more	15	15	15	15	15

Nominal dimensions of OSB Kalevala

Dimension	Size, mm	Ultimate deviation, mm
Thickness	6,0 to 40,0 with gradation of 1,0	± 0,8^*
Length	1250, 2440, 2500, 2650, 2800, 3000, 5000	± 3,0
Width	625, 675, 1220, 1250	± 3,0
* both within one board and a line of boards Notes: Length is defined as a side aligned with the major axis due to its direction, Width is defined as a side aligned with the minor axis due to its direction, Upon agreement with the customer, board production of length and width dimensions, not specified in the table, is possible.

Load-bearing OSB-3 Kalevala for use in humid conditions is bound to be verified for moisture resistance.

Requirements for moisture resistance of OSB-3 Kalevala

Measurement properties of board moisture resistance	Board type	Requirement for board thickness range (mm, nominal)
Measurement properties of board moisture resistance	Board type	6 to 10 incl.	11 to 17 incl.	18 to 25 incl.	26 to 31 incl.	32 to 40 incl.
Tensile strength perpendicular to the plane of the board, MPa, not less (Т_н)	OSB-3	0,15	0,13	0,12	0,06	0,05

Limitation norms of defects on the surface of OSB Kalevala

Defect	Limitation norms of defects
Edge splintering and crumbled corners under GOST 27935	Sporadic ones of depth along the plane - 5 mm and less, length along the edge - 15 mm and less
Foreign particles under GOST 27935, separation of layers under GOST 27935, bubbles	Not allowed
Inclusion of bark and chips of different colours on the plane of the board	Not defined