ISO 2370:2019 pdf free
ISO 2370:2019 pdf free.Textiles – Determination of fineness of flax fibres – Permeametric methods
Withdraw the casing from the chamber. Place it on the 11 mm diameter casing, so that the axes coincide, and push the wad of fibres into this second casing as shown in Figure 3, using a metal ram of 9,8 mm diameter. This transfer of the wad will inevitably create preferential channels. It is essential to eliminate these by the following manual operation; with the casing in the left hand, submit the fibre wad to a transverse vibration between the thumb and second finger of the right hand.
It is recommended that two gauges be used for regular control of the apparatus and verification that it is in good working condition. These gauges consist of pieces of metal, of external dimensions equal to those of the casings used for the introduction of the fibres, with a central hole.
The diameter of the central hole of one of the disks shall be chosen to give a reading corresponding to approximately 1/3 of the measurement scale of the manometer, when the disk is placed in the apparatus,the latter being used as when a measurement of fineness is made, but without fibre in the chamber.The diameter of the central hole of the second disk shall be chosen to give a reading corresponding to approximately 2/3 of the measurement scale of the manometer.
About once per day, place the gauges in the apparatus, passing air through the central hole only, and note the corresponding reading.
The variations in these readings should not exceed, depending on the gauges used, 2 mm or 4 mm of the scale. This procedure forms a useful and rapid check of the functioning of the apparatus.
Measure the rest of test pieces according to 5.5.2 and 5.5.3. Take the mean value of the index of specific surface A’ of five test pieces, and round off to the second place of decimal. The parameter A’ is characteristic of the fineness; however, by convention, the value of A’ shall be used as described in Annex B to enable the results to be expressed as an index of fineness standard, IFS. Express the result to one decimal place.ISO 2370 pdf free download.
