ISO 4324:1977 pdf download.Surface active agents一Powders and granules一Measurement of the angle of repose
1 SCOPE AND FIELD OF APPLICATION
This International Standard specifies a conventional method for the determination of the angle of repose of surface active agents in powder or granular form and of washing powders, free from agglomerates.
This method is also applicable to other powders and granules with comparable properties.
2 REFERENCES
ISO 554, Standard atmospheres for conditioning and/or testing - Specifications.
ISO 607, Surface active agents - Detergents - Methods of sample division. 1)
3 DEFINITION
For the purposes of this International Standard, the following definition applies :angle of repose : The base angle of the cone obtained by flow under the specified conditions.
4 PRINCIPLE
Determination of the angle of repose of the cone obtained by passing a given volume of the product in the form of powder or granules through a special funnel placed at a fixed height above a completely flat and level plate.
5.1.2 Agitatoro comprising two rods placed opposite one another along the whole length of the interior wall of the funnel (5.1.1), and extending Into the stem; these rods should be capable of being turned easily by means of a handle.
5.1.3 Bas.plate, of minimum length 220 mm and minimum width 158 mm. The base-plate shall be completely rigid and shall have a polished surface or be engraved with concentric circles of diameters of from 10 to 100mm, the centres of which shall be coaxial with the axis of the funnel.
5.1.4 Transparent plastic vessel, of minimum diameter
100 mm and minimum height 25 mm, placed 75 mm below the lower end of the funnel (5.1.1). Its internal surface shall be slightly rough. It shall be positioned on the base plate (5.1.3) in such a way that the centre of the vessel and the axis of the funnel coincide, the centring being facilitated by the graduation of the concentric circles on the base-plate.
5.1.5 Funnel support, fixed and positioned so that the axis of the funnel (5.1 .1) is the vertIcal line passing through the centre of the concentric circles engraved on the base• plate (5.1.3).
5.1.6 Supporting rod, comprising a scale graduated in millimetres from 0 to 100, starting from the base-plate (5.1.3). A rod integral with a horizontal slide moves on this scale, allowing the height of the cone to be measured.
7.1 Preparation of sample and test portion
If the laboratory sample has formed agglomerates after a prolonged period of storage, it may still be examined if it regains the fluid state after the vessel containing it has been inverted.
Take 150 ml of the laboratory sample with the graduated measuring cylinder (5.2).ISO 4324 pdf download.