ISO 13517:2020 pdf free.Metal lic powders – Determination of flow rate by means of a calibrated
funnel (Gustavsson flowmeter)
5 Apparatus
5.1 Calibrated funnel, with the dimensions shown in Figure 1 (see Clause 6]. The dimensions shown
for the flowmeter funnel, including the orifice, are not to be considered controlling factors. Calibration
with reference grit, as specified in Clause 6, determines the working flow rate of the funnel.
The funnel shall be made of a non-magnetic, corrosion-resistant metallic material with sufficient wall
thickness and hardness to withstand distortion and excessive wear.
5.2 Stand and horizontal vibration-free base, to support the funnel rigidly, e.g. as indicated in
Figure 2.
5.3 Balance, of sufficient capacity, capable of weighing the test portion to an accuracy of士0,05 g.
5.4 Timing device, capable of measuring the elapsed time to an accuracy of土0,1 s.
5.5 Reference grit, a reference powder used for calibration of the funnel.
6 Calibration of the funnel
6.1 Calibration by the manufacturer of the funnel
The manufacturer shall supply the flowmeter calibrated as follows.
a) Dry the reference grit (5.5) in an open and clean glass jar at 110。C for 60 min in air.
b) Cool the reference grit to room temperature in a desiccator.
c) Weigh out 50,0g士0,1 g of the grit.
d) Follow the procedure outlined in Clause 8.
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 40,0s+0,5s.
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/50 gt 0,5 s/50 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.
If the 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. If the powder contains volatile substances, it shall not be dried.
7.3 Immediately before the test, weigh out a 50,0 g土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士0,1 g
or better. NOTE . The intention of the alternative execution is to facilitate full automation of measurement of flow and apparent density of powders.
7.5 The determination shall be carried out on three test portions.ISO 13517 pdf download.