GB/T 41329-2022 PDF in English
GB/T 41329-2022 (GB/T41329-2022, GBT 41329-2022, GBT41329-2022)
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Determination of flow rate of metallic powders - Calibrated funnel method (Gustavsson flowmeter)
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GB/T 41329-2022: PDF in English (GBT 41329-2022) GB/T 41329-2022
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 77.160
CCS H 16
GB/T 41329-2022 / ISO 13517:2020
Determination of flow rate of metallic powders - Calibrated
funnel method (Gustavsson flowmeter)
[ISO 13517:2020, Metallic powders - Determination of flow rate by means of a
calibrated funnel (Gustavsson flowmeter), IDT]
ISSUED ON: MARCH 09, 2022
IMPLEMENTED ON: OCTOBER 01, 2022
Issued by: State Administration for Market Regulation;
Standardization Administration of the People’s Republic of China.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Terms and definitions... 4
4 Principle ... 4
5 Apparatus ... 4
6 Calibration of the funnel ... 6
7 Sampling ... 6
8 Test procedures ... 7
9 Expression of results ... 7
10 Precision ... 7
11 Test report ... 9
References ... 10
Determination of flow rate of metallic powders - Calibrated
funnel method (Gustavsson flowmeter)
1 Scope
This document specifies a method for determining the flow rate of metallic powders,
including powders for hardmaterials, and mixes of metallic powders and organic
additives (such as lubricants), by means of calibrated funnel (Gustavsson flowmeter).
This document applies to the determination of the flowability of powders capable of
flowing freely through a specified pore size.
2 Normative references
No normative references are listed in this document.
3 Terms and definitions
No terms and definitions are listed in this document.
4 Principle
Measure the time required for 50 g of 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 Chapter 6 for the
calibration of the funnel). The dimensions of the flowmeter funnel, including the orifice,
are not to be considered controlling factors. Determine the working flow rate of the
funnel using reference grit as specified in Chapter 6.
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, capable of supporting 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.
6 Calibration of the funnel
6.1 Calibration by the manufacturer of the funnel
The manufacturer shall calibrate the funnel as follows:
a) Put the reference grit (5.5) in a clean open glass bottle; dry it in the air at 110 °C
for 60 min;
b) Cool the reference grit to room temperature in a desiccator;
c) Weigh 50.0 g ± 0.1 g of the grit;
d) Operate according to the test procedures in Chapter 8;
e) Use the same 50 g of grit to repeat the above procedures, until the deviation of the
five measurement results is less than 0.4 s;
f) The average value of the five measurement results shall be within the range of
40.0 s ± 0.5 s, and marked at the bottom of the funnel.
6.2 Calibration by the user of the funnel
The flow rate of the reference grit shall be determined by the above method. If the flow
rate exceeds 40.0 s/50 g ± 0.5 s/50 g, a correction factor shall be used when measuring
different powders. Use reference grit to measure the new flow rate value of the funnel.
The correction factor is obtained by dividing 40.0 by this new flow rate value.
Whether a calibration is required or not, it is recommended that the users periodically
calibrate the funnel.
It is recommended that, before a correction factor is adopted, the cause of the change
be investigated. If the flow rate decreases, it is probable that repeated use has burnished
the orifice, and the correction factor is adjusted. 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.
When the funnel is used for a period of time, if the reference grit flow time decreases
to less than 37 s during calibration, it is recommended to stop using the funnel.
7 Sampling
7.1 The mass of test sample shall be at least 200 g.
7.2 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. 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 50.0 g ± 0.1 g of test portion.
7.4 Alternatively, weigh 90 g ~ 110 g of test portion, to a precision of ±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 in parallel.
8 Test procedures
Plug the funnel outlet with a dry finger and pour the sample into the funnel. Note that
the powder shall fill the small hole in the lower end of the funnel. When opening the
small hole of the funnel, start the timing device (5.4), and start timing; stop timing when
all the powder in the funnel has flowed out. Record the time used, accurate to 0.1 s.
Alternatively, the orifice of the funnel can also be kept open. Pour the test portion into
the funnel, with the rest of the procedure being the same as above.
If the powder does not flow when the orifice is opened, a tap on the funnel to start the
flow is permitted. If the powder does not flow after a tap, 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 three determination results, and report the data in
s/50 g, rounded to the nearest 1 s/50 g.
If the alternative size of the test portion according to 7.4 is applied, the result of each
determination shall be divided by the mass of the sample, and then be multiplied by 50
g to calculate the flow rate of the 50 g of sample. Then calculate the arithmetic mean of
the calculated values of the three determinations, and express the result in s/50 g.
If a correction factor (6.2) should be used, the average shall be multiplied by this
correction factor.
10 Precision
Test two kinds of plain iron powders and four kinds of mixed powders of iron or bronze
in several laboratories to evaluate the precision of the method. Compositions of the
mixes are presented in Table 1.
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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