4 Apparatus
4.1 Compression tester, motor-driven, mechanical or hydraulic, platen-type, capable of applying load through uniform movement of one or both platens at a relative speed of 10 ± 3mm/min.
The platens shall be
- flat, so that when placed horizontally the difference in height between the lowest and highest points does not exceed 1 mm;
- dimensioned so as to extend over the whole area of the panels with which they are in contact;
- rigid, so as not to deform by more than 1 mm at any point when the tester applies a load of 75 % of its maximum rating, either to a centrally placed 100 mm x 100 mm x 100 mm block having sufficient strength to accept this load without failure, or to four similar blocks placed at the four corners, in the case of swivel-mounted platens.
One platen shall remain horizontal, within two parts per 1000 at all times during the test.
The other platen shall be either rigidly mounted so as to remain horizontal within two parts per 1000 at all times during the test, or be held by a universal joint at its centre and so be free to tilt in any direction.
The working surfaces of platens suitable for testing packages with a length or width or diameter greater than 1000 mm may be locally recessed for fixing bolts, etc.
4.2 Recording device or other means of measurement, with a percentage of error for loads not exceeding ± 2 % of the load and an accuracy of platen displacement of ± 1 mm.
7 Procedure
Whenever possible the test shall be carried out in the same atmospheric conditions as used for conditioning, where this is critical to the materials or application of the package. In other circumstances, the test shall be carried out in atmospheric conditions which are as near as practicable to those used for conditioning.