ISO 13517:2020 pdf download

ISO 13517:2020 pdf download.Metallic powders — Determination of flow rate by means of a calibrated funnel (Gustavsson flowmeter)
1 Scope
This document specifies a method for determining the flow rate of metallic powders, including powders for hardmetals and mixes of metallic powders and organic additives such as lubricants, by means of a calibrated funnel (Gustavsson flowmeter).
The method is applicable only to powders which flow freely through the specified test orifice.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Principle
Measurement of the time required for 50 g of a metallic powder to flow through the orifice of a calibrated funnel of standardized dimensions.
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 ± 0,05 g.
5.4 Timing device, capable of measuring the elapsed time to an accuracy of ± 0,1 s.
5.5 Reference grit, a reference powder used for calibration of the funnel 1) .
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 50,0 g ± 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 40,0 s ± 0,5 s.
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 g ± 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.