ISO 2395:1990(en) Test sieves and test sieving — Vocabulary

ISO 2395:1990(en) Test sieves and test sieving — Vocabulary

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.

International Standard ISO 2395 was prepared by Technical Committee ISO/TC 24, Sieves, sieving and other sizing methods.

This second edition cancels and replaces the first edition (ISO 2395 : 1972), of which it constitutes a technical revision.

1   Scope

This International Standard defines terms to facilitate understanding of the terminology relating to test sieves and test sieving.

It applies to test sieves in accordance with ISO 565, ISO 3310-1, ISO 3310-2 and ISO 3310-3, and to test sieving processes in accordance with ISO 2591-1.

2   Normative references

The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.

ISO 565 : 1990, Test sieves — Metal wire cloth, perforated metal plate and electroformed sheet — Nominal sizes of openings.

ISO 2591-1 : 1988, Test sieving — Methods using test sieves of woven wire cloth and perforated metal plate.

ISO 3310-1 : 1990, Test sieves — Technical requirements and testing — Part 1 : Test sieves of metal wire cloth.

ISO 3310-2 : 1990, Test sieves — Technical requirements and testing — Part 2: Test sieves of perforated metal plate.

ISO 3310-3 : 1990, Test sieves — Technical requirements and testing — Part 3: Test sieves of electroformed sheets.

ISO 9045 : 1990, Industrial screens and screening — Vocabulary.

3   Definitions

3.1   Material to be sieved

3.1.1

particle

Discrete element of the material regardless of its size.

3.1.2

agglomerate

Several particles adhering together.

3.1.3

sample

Representative part taken from a quantity of material.

3.1.4

test sample

Sample which is used in the test.

3.1.5

charge

Test sample, or part of a test sample, placed on a test sieve or on a nest of test sieves.

3.1.6

apparent bulk density

The mass of a charge divided by its volume at the moment when it is placed on the sieving medium.

3.1.7

particle density

The mass of a particle divided by the volume of the particle excluding open pores but including closed pores.

3.2   Test sieves

3.2.1

sieve

Apparatus for the purpose of sieving, consisting of a sieving medium mounted in a frame.

3.2.2

test sieve

Sieve which conforms to a test sieve standard specification for use in particle size analysis by sieving.

3.2.3

certified test sieve

Test sieve that has been certified by an accredited authority as complying with standard specifications.

3.2.4

matched test sieve

Test sieve that reproduces the results of a master test sieve within defined limits for a given material.

3.2.5

full set of test sieves

All the test sieves of a given type of sieving medium in accordance with a standard specification.

3.2.6

nest of test sieves

Set of two or more test sieves assembled according to increasing aperture size from bottom to top and with a lid and a receiver.

3.2.7

sieve depth

H1

Distance between the top rim of the sieve and the sieving medium (see figure 1).

3.2.8

sieve height

H2

Distance between the top and bottom rims of the sieve (see figure 1).

3.2.9

lid

cover

Device which fits snugly over a sieve to prevent the escape of material to be sieved.

3.2.10

receiver

pan

Device which fits snugly beneath a sieve to receive the whole of the passing fraction.

3.2.11

frame

Device which supports the sieving medium at its perimeter and limits the spread of material to be sieved.

3.2.12

sieving medium

A surface containing regularly arranged apertures of uniform shape and size.

3.2.13

woven wire cloth

Sieving medium, produced by a wire weaving process. The wires form square apertures of uniform size.

3.2.14

perforated plate

Sieving medium consisting of a plate with uniform holes in a regular arrangement. The holes may be round or square.

3.2.15

electroformed sheet

Sieving medium made of metal sheet with round or square apertures, produced by electrochemical methods.

3.2.16

aperture size

Dimension defining an opening in a sieving medium.

3.2.17

pitch

(1) For woven wire cloth, the distance between the axes of two adjacent wires in the weft or the warp.

(2) For perforated plate and electroformed sheet, the distance between corresponding points of two adjacent holes.

Figure 1 — Sieve cross-section

3.2.18

percentage open area

(1) For woven wire cloth and electroformed sheet, the ratio of the total area of the apertures to the total area of the cloth or sheet.

(2) For perforated plate, the ratio of the total area of the holes to the total area of the perforated part of the plate (excluding any non-perforated parts).

3.2.19

wire diameter

Diameter of the wire in a woven wire cloth, as measured before weaving.

3.2.20

type of weave

The way in which warp and weft wires cross each other.

3.2.21

warp

All wires running lengthwise of the cloth as woven.

3.2.22

weft

shoot

All wires running crosswise of the cloth as woven.

3.2.23

plain weave

Type of weave in which every warp wire crosses alternately above and below every weft wire and vice versa (see figure 2).

Figure 2 — Plain weave

3.2.24

twilled weave

Type of weave in which every warp wire crosses alternately above and below two weft wires and vice versa (see figure 3).

Figure 3 — Twilled weave

3.2.25

plate thickness

Thickness of a plate before perforation.

3.2.26

bridge width

bar

Distance between the nearest edges of two adjacent holes in a perforated plate or an electroformed sheet.

3.2.27

margin

A non-perforated strip at the edge of a perforated plate or an electroformed sheet.

Note 1 to entry: The width of the margin is measured between the edge of the plate or sheet and the line of the outermost points of the row of holes next to this edge.

3.2.28

punch side

Surface of a perforated plate which the punch entered.

3.3   Test sieving

3.3.1

sieving

Process of separating a mixture of particles according to their size by means of one or more sieves.

Note 1 to entry: The process of separating particles for industrial purposes is designated as "screening" (see ISO 9045).

3.3.2

test sieving

Sieving with one or more test sieves.

3.3.3

particle size analysis by sieving

The separation of a sample of particulate material by test sieving, and the reporting of the results.

3.3.4

hand sieving

Sieving with one sieve or a nest of sieves, which is supported and agitated manually.

3.3.5

machine sieving

Sieving with one sieve or a nest of sieves, in which either the sieve(s) or the charge is agitated mechanically.

3.3.6

dry sieving

Sieving in the absence of a liquid.

3.3.7

wet sieving

Sieving with the help of a liquid.

3.3.8

sieving rate

The quantity of material passing through a sieve in a specified interval of time.

3.3.9

end point

The point in time after which further sieving fails to pass an amount of material sufficient to change the result significantly.

Note 1 to entry: The end point is specified in particular International Standards for each material, in terms of sieving rate, clarity of liquid in wet sieving, or other measurable criteria.

3.3.10

pegging

The condition where particles wedge in the sieve apertures.

3.3.11

blinding

clogging

The condition where very fine particles adhere to a screening surface and reduce the apertures or close them completely.

3.3.12

size fraction

The interval between two quoted limiting sizes of the material with particle sizes between those limits.

3.4   Expression of results

3.4.1

particle size

sieve size of a particle

Smallest aperture size through which a particle will pass if presented in the most favourable attitude.

3.4.2

near-size particle

Particle of size approximately equal to the aperture size of the sieve.

3.4.3

undersize

fines

That portion of the charge which has passed through the apertures of a stated sieve.

3.4.4

oversize

residue

That portion of the charge which has not passed through the apertures of a stated sieve.

3.4.5

size distribution curve

Graphical representation of the results of a particle size analysis.

3.4.6

cumulative oversize distribution curve

Curve obtained by plotting the total (cumulative) percentage by mass retained on each of a set of sieves against the corresponding aperture size.

3.4.7

cumulative undersize distribution curve

Curve obtained by plotting the total (cumulative) percentage by mass passing each of a set of sieves against the corresponding aperture size.