ISO 13517 pdf free download
ISO 13517-2020 pdf free download.Metallic powders一Determination of flow rate by means of a calibrated funnel (Gustavsson flowmeter).
The manufacturer shall supply the flowmeter calibrated as follows.
a) Dry the reference grit (5) in an open and clean glass jar at 110 °C for 60 mm in air.
b) Cool the reference grit to room temperature in a desiccator.
c) Weigh out 50,0 g ± 0,1 g of the grit.
d) Follow the procedure outlined in CJaus8.
e) Repeat the procedure with the same 50 g mass of the grit, until there are five determinations within 0,4 s;
f) The average of these five determinations is stamped on the bottom of the funnel and shall be within 40,Os±0,Ss.
6.2 Calibration by the user of the funnel
The flow rate of the reference sample shall be determined by the above method. If the flow rate has changed to be outside 40,0 s/SO g ± 0,5 s/SO g, a correction factor shall be used when measuring different powders. This correction factor is obtained by dividing 40,0 by this new value for the Reference grit.
It is recommended that the users periodically verify whether a correction is needed or not.
It is recommended that, before a correction factor is adopted, the cause of the change be investigated. lithe flow rate has decreased, it is probable that repeated use has burnished the orifice and a (new) correction factor is justified. An increase in flow rate may indicate a coating of soft powder on the orifice. This coating should be carefully removed and the calibration test repeated.
It is recommended that the use of a funnel be discontinued after the duration of flow of the reference sample has decreased to less than 37 s.
7 Sampling
7.1 The mass of the test sample shall be at least 200 g.
7.2 In general, the powder shall be tested in the as-received condition. In certain cases, and after agreement between the supplier and user, the powder may be dried. However, if the powder is susceptible to oxidation, the drying shall take place in a vacuum or in inert gas. lithe powder contains volatile substances, it shall not be dried.
7.3 Immediately before the test, weigh out a 50,0 g ± 0,1 g test portion.
7.4 Alternatively, a test portion of 90 g to 110 g can be sampled and weighed to a precision of ± 0,1 g or better.
NOTE The intention of the alternative execution is to facllttate full automation of measurement of flow and apparent density of powders.
7.5 The determination shall be carried out on three test portions.
8 Procedure
Transfer the test portion to the funnel, keeping the discharge orifice closed by a dry finger. Take care that the stem of the funnel is filled with powder. Start the timing device (5A) when the orifice is opened and stop it at the instant when the last of the powder leaves the orifice. Record the elapsed time measured to the nearest 0,1 s.
Alternatively, the orifice can be kept open, when the test portion is transferred to the funnel with the rest of the procedure being the same.
If the powder does not begin to flow when the orifice is opened, one slight tap on the funnel to start the flow is permitted. If this has no effect, or if the flow stops during the test, the powder is considered to possess no flowability according to the test method described in this document.
9 Expression of results
Calculate the arithmetic mean of the results of the three determinations and report the value in seconds per SO g, rounded to the nearest second.
lithe alternative size of the test portion according to Z4 is applied, the result of each determination shall, before the calculation of the arithmetic mean of the results, be divided by the mass of the sample and then be multiplied by 50 g. The result is thus recalculated in seconds per 50 g.
If a correction factor (see .,2) should be used, the average shall be multiplied by this correction factor.ISO 13517 pdf download.
