EN 323-1993 pdf download.Wood-based panels Determination of density.
This EN 323 specifies a method for determining the density of test pieces of wood-based panels. Such result may be used to estimate the density of wood-based panels according to EN 326-I.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places In the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard, only when incorporated in it by amendment or revision. For undated references the Latest edition of the publication referred to applies.
EN 325 Woocl-based panels — Determination of dimensw??s of test pieces
EN 326-1 Wood-base(l panels — Sampling, cuuing and inspection Part 1: Sampling and cutting of test pieces and expmwsion of test results U
3 PrincIple
Density is determined as the ratio of the ma&s of each test piece, to its volume, both measured at the same moisture content, and the use of these results to estimate the density of whole boards.
4 Apparatus
4.1 Instrument for t.hlckncts measurement Micrometer or similar measuring instrument, having flat and parallel circular measuring surfaces of (16 ± 1) mm diameter and an operation force of (4 ± 1 N. The graduation of the arnanitus h1l
4.2 Instrument for length and width measurement
Sliding caliper, or any other instrument with measuring surfaces of at. least 6 mm width, graduated to allow reading to 0,1 mm.
4.3 Balance
Balance, allowing measurement to 0,01 g.
5 Test pieces
5.1 Sampling and cutting
Sampling and cutting of the test pieces shall be carried out in accordance with EN 326-i.
5.2 Dimensions
The test pieces shall be square in shape, with sides of a nominal length of 50 mm.
hi the case of extruded panels, celluiar panels, or panels of similar structure with cavities parallel to the length or width of the test piece, the total length or width of the test piece shall be at least twice the length or width of any individual core element (i.e. two tube diameters plus two web thicknesses) and the test pieces shall have a symmetrical cross-sectional area as shown in figure 1.
5.3 ConditionIng
if necessary, the test pieces shall be conditioned to constant mass in an atmosphere with a relative humidity of (65 ± 5) % and a trnpemture of (20 ± 2) °C. Constant mass is considered to be reached when the results of two successive weighing operations, carried out at an Interval of 24 h, do not differ by more than 0,1 % of the mass of the test piece.
6 Procedure
61 WeIghing
Weigh each test piece to an accuracy of 0,01 g.
6.2 Measurement of dimensions
Measure the dimensions of each test piece, in accordance with EN 326, as follows.
a) Measure the thickness, C, at a point of the intersection of the diagonals as shown in figure 2 (unless this coincides with a surface irregularity which may ini]uence the measurement) to an accuracy of 0,05 mm.
Apply the measuring instrument slowly to the surfaces of the test piece.
b) Measure b1 and b2, at two points, parallel to the edges of the test piece, along lines which pass through the centres of opposite edges as shown in figure 2, to an accuracy of 0,1 mm.EN 323-1993 pdf download.