SIST ISO 12301:2008
Plain bearings - Quality control techniques and inspection of geometrical and material quality characteristics
Plain bearings - Quality control techniques and inspection of geometrical and material quality characteristics
This International Standard specifies quality control techniques and inspection of the geometrical and material quality characteristics of the following types of plain bearings: - thin-walled half-bearings with or without flange, as specified in ISO 3548; - metallic thick-walled half-bearings (with and without flange) that are manufactured as halves but that are necessarily interchangeable and have the ratio s3 Do 0,11; - wrapped bushes, as specified in ISO 3547; - unsplit metallic bushes (with and without flange) made from solid and multilayer materials and with outside diameters up to 230 mm; - solid polymer bushes (with and without flange) with inside diameters up to 200 mm; - ring-type thrust washers and pressed bimetallic half-thrust washers, as specified in ISO 6525 and ISO 6526, respectively; - bushes made from sintered material, as specified in ISO 2795.
Gleitlager - Prüftechniken und Prüfung der Qualitätsmerkmale von Geometrie und Werkstoff
Paliers lisses - Techniques de contrôle de la qualité et vérifications des caractéristiques de qualité géométriques et des matériaux
Drsni ležaji - Postopek kontrole kakovosti in kontrola geometrijskih in materialnih značilnosti
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INTERNATIONAL ISO
STANDARD 12301
Second edition
2007-10-15
Plain bearings — Quality control
techniques and inspection of geometrical
and material quality characteristics
Paliers lisses — Techniques de contrôle de la qualité et vérifications
des caractéristiques de qualité géométriques et des matériaux
Reference number
ISO 12301:2007(E)
©
ISO 2007
---------------------- Page: 1 ----------------------
ISO 12301:2007(E)
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ii © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
Contents Page
Foreword. iv
1 Scope .1
2 Normative references .1
3 Terms and definitions .2
4 Symbols and units.4
5 Summary of defined quality characteristics.5
6 Geometrical quality characteristics.7
6.1 Wall thickness, s .7
3
6.2 Outside diameter, D .13
o
6.3 Inside diameter, D .14
i
6.4 Width, B.17
6.5 Locating features.18
6.6 Lubricant feed and distribution features.19
6.7 Surface conditions.20
6.8 Crush height, a (peripheral length).21
6.9 Free spread.22
6.10 Straightness of sliding surface .23
6.11 Joint face taper, h .24
∆
6.12 Back contact.24
6.13 Joint displacement, B .25
∆
6.14 Height of thrust half-washer, H .25
6.15 Flatness .26
6.16 Flange diameter, D .27
fl
6.17 Distance between flanges, a .28
fl
6.18 Flange thickness, s .29
fl
6.19 Perpendicularity (squareness) of flange .30
6.20 Geometric deviations .31
7 Material quality characteristics .35
7.1 Metallic solid materials .35
7.2 Metallic multilayer material.36
7.3 Polymer layer material .38
7.4 Solid polymer material .39
7.5 Sintered material.39
Annex A (informative) Calculation of tangential load.40
Bibliography .47
© ISO 2007 – All rights reserved iii
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ISO 12301:2007(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. 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.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 12301 was prepared by Technical Committee ISO/TC 123, Plain bearings, Subcommittee SC 5, Quality
analysis and assurance.
This second edition cancels and replaces the first edition (ISO 12301:1992), which has been technically
revised. (It also incorporates the Technical corrigendum ISO 12301:1992/Cor. 1:1995.)
iv © ISO 2007 – All rights reserved
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INTERNATIONAL STANDARD ISO 12301:2007(E)
Plain bearings — Quality control techniques and inspection of
geometrical and material quality characteristics
1 Scope
This International Standard specifies quality control techniques and inspection of the geometrical and material
quality characteristics of the following types of plain bearings:
⎯ thin-walled half-bearings with or without flange, as specified in ISO 3548;
⎯ metallic thick-walled half-bearings (with and without flange) that are manufactured as halves but that are
necessarily interchangeable and have the ratio s : D > 0,11;
3 o
⎯ wrapped bushes, as specified in ISO 3547;
⎯ unsplit metallic bushes (with and without flange) made from solid and multilayer materials and with
outside diameters up to 230 mm;
⎯ solid polymer bushes (with and without flange) with inside diameters up to 200 mm;
⎯ ring-type thrust washers and pressed bimetallic half-thrust washers, as specified in ISO 6525 and
ISO 6526, respectively;
⎯ bushes made from sintered material, as specified in ISO 2795.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 2795, Plain bearings — Sintered bushes — Dimensions and tolerances
ISO 3274 Geometrical Product Specifications (GPS) — Surface texture: Profile method — Nominal
characteristics of contact (stylus) instruments
ISO 3547-1, Plain bearings — Wrapped bushes — Part 1: Dimensions
ISO 3547-2, Plain bearings — Wrapped bushes — Part 2: Test data for outside and inside diameters
ISO 3547-3, Plain bearings — Wrapped bushes — Part 3: Lubrication holes, grooves and indentations
ISO 3547-4, Plain bearings — Wrapped bushes — Part 4: Materials
ISO 3547-5, Plain bearings — Wrapped bushes — Part 5: Checking the outside diameter
ISO 3547-6, Plain bearings — Wrapped bushes — Part 6: Checking the inside diameter
© ISO 2007 – All rights reserved 1
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ISO 12301:2007(E)
ISO 3547-7, Plain Bearings — Wrapped bushes — Part 7: Measurement of wall thickness of thin-walled
bushes
ISO 3548, Plain bearings — Thin-walled half bearings with or without flange — Tolerances, design features
and methods of test
ISO 4287, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Terms, definitions
and surface texture parameters
ISO 4288, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Rules and
procedures for the assessment of surface texture
ISO 4378-1, Plain bearings — Terms, definitions and classification — Part 1: Design, bearing materials and
their properties
ISO 4384-1, Plain bearings — Hardness testing of bearing metals — Part 1: Compound materials
ISO 4384-2, Plain bearings — Hardness testing of bearing metals — Part 2: Solid materials
ISO 4386-1, Plain bearings — Metallic multilayer plain bearings — Part 1: Non-destructive ultrasonic testing of
bond
ISO 4386-2 Plain bearings — Metallic multilayer plain bearings — Part 2: Destructive testing of bond for
bearing metal layer thicknesses W 2 mm
ISO 4386-3, Plain bearings — Metallic multilayer plain bearings — Part 3: Non-destructive penetrant testing
ISO 6524:1992, Plain bearings — Thin-walled half bearings — Checking of peripheral length
ISO 6525, Plain bearings — Ring type thrust washers made from strip — Dimensions and tolerances
ISO 6526, Plain bearings — Pressed bimetallic half thrust washers — Features and tolerances
ISO 6691, Thermoplastic polymers for plain bearings — Classification and designation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4378-1 and the following apply.
3.1
quality of plain bearing
condition which renders a plain bearing fit to fulfil given requirements
NOTE The given requirements are generally dependent upon the intended use.
3.2
quality control techniques
method, equipment and procedure by means of which the quality of a plain bearing is assessed
3.3
quality characteristic
characteristic by means of which the quality of a plain bearing is judged
3.4
inspection
checking of one or more quality characteristics of a plain bearing with applicable requirements
2 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
3.5
uncertainty of measurement
parameter, associated with the result of a measurement, that characterizes the dispersion of the values that
could reasonably be attributed to the measurand
[Guide 99]
NOTE The uncertainty, u, should be evaluated using statistical methods, e.g. repeatability and reproducibility studies,
or as shown below:
ut=± ⋅ σ
where
t is the stochastic variable according to Student's t distribution; t = 2 and corresponds to a statistical probability in
measurement P = 95 %, for which the probability of exceeding the value (1 – P) = 0,05 or 5 %;
σ is the standard deviation of the whole lot.
NOTE 1 The uncertainty of measurement is normally ± 10 % of the tolerance.
3.6
measuring points
agreed points established to facilitate agreement on checking
NOTE The establishment of measuring points does not preclude the need to comply with dimensional specifications
in other areas.
3.7
measuring lines
agreed lines established to facilitate agreement on checking
NOTE The establishment of measuring lines does not preclude the need to comply with dimensional specifications in
other areas.
3.8
tolerance
range between the upper specified limit and the lower specified limit
© ISO 2007 – All rights reserved 3
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ISO 12301:2007(E)
4 Symbols and units
For the purposes of this document, the symbols and units given in Table 1 apply.
Table 1
Symbol Parameter SI unit
a
Crush height millimetres
∆a Measured change in a millimetres
a
Distance to measuring position millimetres
ch
a Distance between gauge faces millimetres
E
a Distance between flanges millimetres
fl
A Effective cross-section square millimetres
eff
B Width millimetres
B Joint displacement millimetres
∆
d Diameter of the checking block bore millimetres
ch
D
Housing diameter millimetres
H
D Flange diameter millimetres
fl
D Diameter measured across the joint in the free state; free spread millimetres
fs
diameter
D
Inside diameter millimetres
i
D Outside diameter millimetres
o
ν Elastic reduction millimetres
F
Checking load newtons
ch
F Measuring pin load newtons
pin
F Tangential load of bearing as fitted newtons
tan
h
Radius for flange thickness measurement millimetres
ch
h Joint face taper millimetres
∆
H Height millimetres
M Number of measuring lines —
s Thickness of the backing layer millimetres
1
s Thickness of the bearing material layer millimetres
2
s
Thickness of the bearing material layer, reduced millimetres
2, red
s Flange thickness millimetres
fl
s Wall thickness millimetres
3
T
Tolerance millimetres
t Stochastic variable —
u Uncertainty of measurement millimetres
x , x , ., x Individual measured values millimetres
1 2 i
y Flatness gauge gap millimetres
Maximum diametral deformation in compression millimetres
ε
max
ε Minimum diametral deformation in compression millimetres
min
σ Standard deviation —
newtons per square
σ Tangential strength
tan
millimetre
Stress newtons per square
Φ
millimetre
4 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
5 Summary of defined quality characteristics
A summary of defined quality characteristics is given in Table 2 for the convenience of users of this
International Standard, as guidance indicating which defined quality characteristics are relevant to each type
of bearing.
The sequence of the characteristics listed in Table 2 does not determine their importance. The manufacturer
and user shall agree on priorities for the quality characteristics that, from their points of view, are required to
assure reliability and lifetime of the product.
Table 2
Type of plain bearing
Relevant
Thin- Thick- Thrust
clause/
Unsplit Solid
Quality characteristics
walled walled washer
Wrapped Sintered
subclause
metallic polymer
half- half- bush bush (ring
number
bush bush
bearing bearing and half)
a
6 Geometrical quality characteristics
6.1 Wall thickness, s
3
6.1.1 Line measurement
+ + + + + − −
6.1.2 Point measurement
+ + + + + + +
6.2 Outside diameter, D
− + + + + + +
o
6.3 Inside diameter, D − + + + + + +
i
6.4 Width, B
+ + + + + + −
6.5 Locating features
+ + + + + − +
6.6 Lubricant feed and
+ + + + + − +
distribution features
6.7 Surface conditions + + + + + − +
Crush height, a
6.8 + − − − − − −
6.9 Free spread
+ + − − − − −
6.10 Straightness of sliding
+ − − − − − −
surface
6.11 Joint face taper, h + − − − − − −
∆
6.12 Back contact + − − − − − −
6.13 Joint displacement, B
− − + − − − −
∆
6.14 Height of thrust
− − − − − (+) +
half-washer, H
6.15 Flatness − − − − − (+) +
Flange diameter, D
6.16 + + + + + + −
fl
6.17 Distance between
+ + + + + − −
flanges, a
fl
6.18 Flange thickness, s
+ + + + + + −
fl
6.19 Perpendicularity
+ + + + + (+) −
(squareness) of flange
6.20 Geometric deviations
6.20.1 Cylindricity
− (+) − + − (+) −
6.20.2 Run-out of thrust face − (+) − + + (+) −
6.20.3 Coaxiality and − + − + + + −
concentricity
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ISO 12301:2007(E)
Table 2 (continued)
Type of plain bearing
Relevant
Thin- Thick- Thrust
clause/
Unsplit Solid
Quality characteristics
walled walled Wrapped Sintered washer
subclause
metallic polymer
half- half- (ring
bush bush
number
bush bush
bearing bearing and half)
a
7 Material quality characteristics
7.1 Metallic solid material
7.1.1 Hardness − + + + − − +
7.1.2 Material composition
− + + + − − +
7.1.3 Material structure
− + + + − − +
7.2 Metallic multilayer material
7.2.1 Overlay properties
+ + + − − − +
7.2.2 Lining properties + + + − − − +
7.2.3 Backing properties + + + − − − +
7.2.4 Adhesion (bond) of + + + − − − +
adjacent layers
7.3 Polymer layer material
7.3.1 Overlay properties − − + − − − (+)
7.3.2 Lining properties
− − + − − − (+)
7.3.3 Backing properties
− − + − − − (+)
7.3.4 Adhesion (bond) of − − + − − − (+)
adjacent layers
7.4 Solid polymer material
7.4.1 Material composition − − − − + − −
7.4.2 Material structure − − − − + − −
7.5 Sintered material
7.5.1 Material composition − − − − − + −
7.5.2 Material structure
− − − − − + −
a
Significance of symbols:
Plus sign indicates that the characteristic is generally applicable to the corresponding type of bearing.
Plus sign in parentheses indicates that this characteristic is not always applicable.
Minus sign indicates that the characteristic is not relevant for the corresponding type of bearing.
6 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
6 Geometrical quality characteristics
In order to assess plain bearing quality, important dimensional quality characteristics are specified in
Clause 6.
Unless otherwise stated, the dimensions in the tables and figures are given in millimetres.
6.1 Wall thickness, s
3
See Table 3.
Table 3
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/measuring
Applicability Test equipment
geometrical characteristic principle
NOTE This test method is also
Metallic See Figure 1.
applicable when measuring joint face
thin-walled
bore relief.
half-bearing
Figure 1 Figure 2
Metallic See Figure 1. Measured normal to the back Device for measuring wall
thick-walled surface in the radial direction thickness
half-bearing using the spherical faces of the
measuring pins
Wrapped See Figure 3 and Measure in accordance with Device for measuring wall
bush ISO 3547-7. ISO 3547-7. thickness (see ISO 3547-7)
Depending on the manufacturing
process, the back of the wrapped
bush can show slight hollows.
The wall thickness shall,
therefore, be measured outside
these hollows, i.e. on the
“bearing areas”
(see ISO 3547-7). In the cases
D < 8 or D > 150, the test
i i
method shall be subject to
agreement between the
manufacturer and user.
Figure 3
© ISO 2007 – All rights reserved 7
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ISO 12301:2007(E)
Table 3 (continued)
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/measuring
Applicability Test equipment
geometrical characteristic principle
Unsplit See Figure 4. Similar to Figure 2 Device for measuring wall
metallic thickness
bush
Figure 4
Solid polymer See Figure 4 Similar to Figure 2 Device for measuring wall
bush thickness
Measure normal to the back
surface in the radial direction
using the spherical faces of the
measuring pins.
Sintered bush See Figure 4. Similar to Figure 2 Device for measuring wall
thickness
Thrust washer Axial distance between the two Measure parallel to the axial Device for measuring wall
faces of the washer direction using the spherical thickness
(see Figure 5) faces of the measuring pins
(see Figure 6).
Figure 5 Figure 6
8 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
6.1.1 Line measurement (wall thickness)
See Table 4.
Table 4
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/
Applicability Test equipment
geometrical characteristic measuring principle
Metallic thin-walled half-bearing
Wrapped bush; See Figure 7 and ISO 3547-7. The thickness of the half-bearing or Device for measuring wall
unsplit metallic bush is measured continuously on thickness
Each measuring line distance, a ,
ch
bush one, two or three predetermined or
is specified from the beginning of
agreed measuring lines
the sliding surface or from the end
(see Figure 7).
face by adding the nominal value of
It can be necessary to modify the
the chamfer. This measurement
defined position of the measuring
may also be used for an unsplit
lines to avoid design features, such
bush.
as grooves, etc.
Key
1 measuring lines
a = 1,5
ch
Distance to Number of
Width measuring measuring
position lines
a
B M
ch
u 15
B/2 1
> 15 u 50
4 2
> 50 6 2
Figure 7
© ISO 2007 – All rights reserved 9
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ISO 12301:2007(E)
Table 4 (continued)
Dimensions in millimetres, unless otherwise stated
Definition of
measured Test method/
Applicability Test equipment
geometrical measuring principle
characteristic
The thickness of the
Metallic See Figure 7. Device for measuring wall thickness; for details see
thick-walled half-bearing is measured the following table.
Each measuring line
continuously on two
half-bearing
distance, a , is Wall Measuring pin Uncertainty of Radius of
ch
predetermined or agreed
thickness load measurement measuring
specified from the
measuring lines
N anvil
beginning of the
(see Figure 7).
sliding surface or
s u 10 0,8 u F u 1,5
± 0,001 5
3 pin
from the end face by In the case where s > 25, the
3 ± 0,2
3
10 < s u 25 1,5 < F u 2,5
adding the nominal test method shall be subject to ± 0,002
3 pin
value of the agreement between the
chamfer. manufacturer and user.
It can be necessary to modify
the defined position of the
measuring lines to avoid
design features, such as
grooves, etc.
Solid See Figure 7. The thickness of the bush is Device for measuring wall thickness; for details see
polymer measured continuously on the following table.
Each measuring line
bush one, two or three
distance, a , is Outside Measuring pin Radius of Uncertainty of
ch
predetermined or agreed
diameter load measuring measurement
specified from the
measuring lines
anvil
beginning of the
N
(see Figure 7).
sliding surface or
from the end face by It can be necessary to modify D u 150 0,8 u F u 1,5
3 ± 0,2
o pin
adding the nominal the defined position of the
± 0,005
value of the measuring lines to avoid
150 < D u 300 1,5 < F u 2,5
chamfer. design features such as
5 ± 0,2
o pin
grooves, etc.
10 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
6.1.2 Point measurement (wall thickness)
See Table 5.
Table 5
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/
Applicability Test equipment
geometrical characteristic measuring principle
Metallic See Figure 2.
thin-walled
half-bearing
Wrapped Wall thickness measured at determined According to ISO 3547-7 Device for measuring wall thickness
bush; measuring points; see ISO 3547-7
It can be necessary to
unsplit
modify the defined
metallic
position of the measuring
bush
points to avoid design
features such as
grooves, etc. This
measurement can also
be used for an unsplit
bush.
Metallic Wall thickness measured at determined It can be necessary to External micrometer with dial
thick-walled measuring points which are subject to modify the defined indicator
half-bearing agreement between the manufacturer position of the measuring
and user. points to avoid design
features such as
grooves, etc.
Solid Wall thickness measured at determined It can be necessary to Device for measuring wall thickness
polymer measuring points (see Figure 8) modify the defined
External micrometer with dial
bush; position of the measuring
indicator
sintered bush points to avoid design
features such as
grooves, etc.
Distance to
Number of
Width measuring
measuring lines
position
a
B M
ch
u 15
B/2 1
> 15 u 50 4 2
> 50 6 2
Figure 8
© ISO 2007 – All rights reserved 11
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ISO 12301:2007(E)
Table 5 (continued)
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/
Applicability Test equipment
geometrical characteristic measuring principle
Wall thickness measured at determined
Thrust The thrust washer is External micrometer with dial
washer measuring points (P) on measuring measured at measuring indicator
lines at a distance, a , from the inside
points positioned as
ch
Device for measuring wall thickness;
diameter of the washers, as shown in shown in Figure 9.
for details see the following table
Figure 9
It can be necessary to
modify the defined
position of the measuring Radius of
Measuring pin
measuring anvil
points to avoid design
load
features such as
N
grooves, etc.
0,8 u F u 1,5
3 ± 0,2
pin
Key
1 measuring points
a
For thrust half-washers, α = 80°;
for thrust washers, α = 120°.
Figure 9
12 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
6.2 Outside diameter, D
o
See Table 6.
Table 6
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/measuring
Applicability Test equipment
geometrical characteristic principle
Metallic Outside diameter of a metallic thick- Measured in the radial direction Measuring device
thick-walled walled half-bearing is measured as a between two flat parallel faces
Holding device
half-bearing pair in the free condition, determined of the measuring device
using Equation (1) (see Figure 10) (see Figure 11)
xx++05, x
()
312
D = (1)
o
2
Figure 10 Figure 11
Wrapped See ISO 3547-2 and 3547-5. In accordance with ISO 3547-5 In accordance with
bush ISO 3547-5
Unsplit Outside diameter of a bush measured Measured in the radial direction Measuring device
metallic in the free condition, determined as the between two flat parallel faces
External micrometer with dial
bush; arithmetic mean of at least two of the measuring device
indicator
solid polymer measurements (see Figure 12) (see Figure 11).
bush;
Holding device
In cases where the wall
sintered bush
thickness outside diameter ratio
is such that
the bush may be considered
to be flexible, D may be
o
measured according to
method A specified in
ISO 3547-5 for wrapped bushes.
Figure 12
© ISO 2007 – All rights reserved 13
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ISO 12301:2007(E)
Table 6 (continued)
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/measuring
Applicability Test equipment
geometrical characteristic principle
Thrust washer Outside diameter of a thrust washer Measured in the radial direction Standard test equipment
measure
...
SLOVENSKI STANDARD
SIST ISO 12301:2008
01-julij-2008
1DGRPHãþD
SIST ISO 12301:2002
'UVQLOHåDML7HKQLNHNRQWUROHNDNRYRVWLLQNRQWURODJHRPHWULMVNLKLQPDWHULDOQLK
]QDþLOQRVWL
Plain bearings - Quality control techniques and inspection of geometrical and material
quality characteristics
Gleitlager - Prüftechniken und Prüfung der Qualitätsmerkmale von Geometrie und
Werkstoff
Paliers lisses - Techniques de contrôle de la qualité et vérifications des caractéristiques
de qualité géométriques et des matériaux
Ta slovenski standard je istoveten z: ISO 12301:2007
ICS:
21.100.10 Drsni ležaji Plain bearings
SIST ISO 12301:2008 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
INTERNATIONAL ISO
STANDARD 12301
Second edition
2007-10-15
Plain bearings — Quality control
techniques and inspection of geometrical
and material quality characteristics
Paliers lisses — Techniques de contrôle de la qualité et vérifications
des caractéristiques de qualité géométriques et des matériaux
Reference number
ISO 12301:2007(E)
©
ISO 2007
---------------------- Page: 2 ----------------------
ISO 12301:2007(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.
COPYRIGHT PROTECTED DOCUMENT
© ISO 2007
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
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ii © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
Contents Page
Foreword. iv
1 Scope .1
2 Normative references .1
3 Terms and definitions .2
4 Symbols and units.4
5 Summary of defined quality characteristics.5
6 Geometrical quality characteristics.7
6.1 Wall thickness, s .7
3
6.2 Outside diameter, D .13
o
6.3 Inside diameter, D .14
i
6.4 Width, B.17
6.5 Locating features.18
6.6 Lubricant feed and distribution features.19
6.7 Surface conditions.20
6.8 Crush height, a (peripheral length).21
6.9 Free spread.22
6.10 Straightness of sliding surface .23
6.11 Joint face taper, h .24
∆
6.12 Back contact.24
6.13 Joint displacement, B .25
∆
6.14 Height of thrust half-washer, H .25
6.15 Flatness .26
6.16 Flange diameter, D .27
fl
6.17 Distance between flanges, a .28
fl
6.18 Flange thickness, s .29
fl
6.19 Perpendicularity (squareness) of flange .30
6.20 Geometric deviations .31
7 Material quality characteristics .35
7.1 Metallic solid materials .35
7.2 Metallic multilayer material.36
7.3 Polymer layer material .38
7.4 Solid polymer material .39
7.5 Sintered material.39
Annex A (informative) Calculation of tangential load.40
Bibliography .47
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ISO 12301:2007(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. 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.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 12301 was prepared by Technical Committee ISO/TC 123, Plain bearings, Subcommittee SC 5, Quality
analysis and assurance.
This second edition cancels and replaces the first edition (ISO 12301:1992), which has been technically
revised. (It also incorporates the Technical corrigendum ISO 12301:1992/Cor. 1:1995.)
iv © ISO 2007 – All rights reserved
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INTERNATIONAL STANDARD ISO 12301:2007(E)
Plain bearings — Quality control techniques and inspection of
geometrical and material quality characteristics
1 Scope
This International Standard specifies quality control techniques and inspection of the geometrical and material
quality characteristics of the following types of plain bearings:
⎯ thin-walled half-bearings with or without flange, as specified in ISO 3548;
⎯ metallic thick-walled half-bearings (with and without flange) that are manufactured as halves but that are
necessarily interchangeable and have the ratio s : D > 0,11;
3 o
⎯ wrapped bushes, as specified in ISO 3547;
⎯ unsplit metallic bushes (with and without flange) made from solid and multilayer materials and with
outside diameters up to 230 mm;
⎯ solid polymer bushes (with and without flange) with inside diameters up to 200 mm;
⎯ ring-type thrust washers and pressed bimetallic half-thrust washers, as specified in ISO 6525 and
ISO 6526, respectively;
⎯ bushes made from sintered material, as specified in ISO 2795.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 2795, Plain bearings — Sintered bushes — Dimensions and tolerances
ISO 3274 Geometrical Product Specifications (GPS) — Surface texture: Profile method — Nominal
characteristics of contact (stylus) instruments
ISO 3547-1, Plain bearings — Wrapped bushes — Part 1: Dimensions
ISO 3547-2, Plain bearings — Wrapped bushes — Part 2: Test data for outside and inside diameters
ISO 3547-3, Plain bearings — Wrapped bushes — Part 3: Lubrication holes, grooves and indentations
ISO 3547-4, Plain bearings — Wrapped bushes — Part 4: Materials
ISO 3547-5, Plain bearings — Wrapped bushes — Part 5: Checking the outside diameter
ISO 3547-6, Plain bearings — Wrapped bushes — Part 6: Checking the inside diameter
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ISO 12301:2007(E)
ISO 3547-7, Plain Bearings — Wrapped bushes — Part 7: Measurement of wall thickness of thin-walled
bushes
ISO 3548, Plain bearings — Thin-walled half bearings with or without flange — Tolerances, design features
and methods of test
ISO 4287, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Terms, definitions
and surface texture parameters
ISO 4288, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Rules and
procedures for the assessment of surface texture
ISO 4378-1, Plain bearings — Terms, definitions and classification — Part 1: Design, bearing materials and
their properties
ISO 4384-1, Plain bearings — Hardness testing of bearing metals — Part 1: Compound materials
ISO 4384-2, Plain bearings — Hardness testing of bearing metals — Part 2: Solid materials
ISO 4386-1, Plain bearings — Metallic multilayer plain bearings — Part 1: Non-destructive ultrasonic testing of
bond
ISO 4386-2 Plain bearings — Metallic multilayer plain bearings — Part 2: Destructive testing of bond for
bearing metal layer thicknesses W 2 mm
ISO 4386-3, Plain bearings — Metallic multilayer plain bearings — Part 3: Non-destructive penetrant testing
ISO 6524:1992, Plain bearings — Thin-walled half bearings — Checking of peripheral length
ISO 6525, Plain bearings — Ring type thrust washers made from strip — Dimensions and tolerances
ISO 6526, Plain bearings — Pressed bimetallic half thrust washers — Features and tolerances
ISO 6691, Thermoplastic polymers for plain bearings — Classification and designation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4378-1 and the following apply.
3.1
quality of plain bearing
condition which renders a plain bearing fit to fulfil given requirements
NOTE The given requirements are generally dependent upon the intended use.
3.2
quality control techniques
method, equipment and procedure by means of which the quality of a plain bearing is assessed
3.3
quality characteristic
characteristic by means of which the quality of a plain bearing is judged
3.4
inspection
checking of one or more quality characteristics of a plain bearing with applicable requirements
2 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
3.5
uncertainty of measurement
parameter, associated with the result of a measurement, that characterizes the dispersion of the values that
could reasonably be attributed to the measurand
[Guide 99]
NOTE The uncertainty, u, should be evaluated using statistical methods, e.g. repeatability and reproducibility studies,
or as shown below:
ut=± ⋅ σ
where
t is the stochastic variable according to Student's t distribution; t = 2 and corresponds to a statistical probability in
measurement P = 95 %, for which the probability of exceeding the value (1 – P) = 0,05 or 5 %;
σ is the standard deviation of the whole lot.
NOTE 1 The uncertainty of measurement is normally ± 10 % of the tolerance.
3.6
measuring points
agreed points established to facilitate agreement on checking
NOTE The establishment of measuring points does not preclude the need to comply with dimensional specifications
in other areas.
3.7
measuring lines
agreed lines established to facilitate agreement on checking
NOTE The establishment of measuring lines does not preclude the need to comply with dimensional specifications in
other areas.
3.8
tolerance
range between the upper specified limit and the lower specified limit
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ISO 12301:2007(E)
4 Symbols and units
For the purposes of this document, the symbols and units given in Table 1 apply.
Table 1
Symbol Parameter SI unit
a
Crush height millimetres
∆a Measured change in a millimetres
a
Distance to measuring position millimetres
ch
a Distance between gauge faces millimetres
E
a Distance between flanges millimetres
fl
A Effective cross-section square millimetres
eff
B Width millimetres
B Joint displacement millimetres
∆
d Diameter of the checking block bore millimetres
ch
D
Housing diameter millimetres
H
D Flange diameter millimetres
fl
D Diameter measured across the joint in the free state; free spread millimetres
fs
diameter
D
Inside diameter millimetres
i
D Outside diameter millimetres
o
ν Elastic reduction millimetres
F
Checking load newtons
ch
F Measuring pin load newtons
pin
F Tangential load of bearing as fitted newtons
tan
h
Radius for flange thickness measurement millimetres
ch
h Joint face taper millimetres
∆
H Height millimetres
M Number of measuring lines —
s Thickness of the backing layer millimetres
1
s Thickness of the bearing material layer millimetres
2
s
Thickness of the bearing material layer, reduced millimetres
2, red
s Flange thickness millimetres
fl
s Wall thickness millimetres
3
T
Tolerance millimetres
t Stochastic variable —
u Uncertainty of measurement millimetres
x , x , ., x Individual measured values millimetres
1 2 i
y Flatness gauge gap millimetres
Maximum diametral deformation in compression millimetres
ε
max
ε Minimum diametral deformation in compression millimetres
min
σ Standard deviation —
newtons per square
σ Tangential strength
tan
millimetre
Stress newtons per square
Φ
millimetre
4 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
5 Summary of defined quality characteristics
A summary of defined quality characteristics is given in Table 2 for the convenience of users of this
International Standard, as guidance indicating which defined quality characteristics are relevant to each type
of bearing.
The sequence of the characteristics listed in Table 2 does not determine their importance. The manufacturer
and user shall agree on priorities for the quality characteristics that, from their points of view, are required to
assure reliability and lifetime of the product.
Table 2
Type of plain bearing
Relevant
Thin- Thick- Thrust
clause/
Unsplit Solid
Quality characteristics
walled walled washer
Wrapped Sintered
subclause
metallic polymer
half- half- bush bush (ring
number
bush bush
bearing bearing and half)
a
6 Geometrical quality characteristics
6.1 Wall thickness, s
3
6.1.1 Line measurement
+ + + + + − −
6.1.2 Point measurement
+ + + + + + +
6.2 Outside diameter, D
− + + + + + +
o
6.3 Inside diameter, D − + + + + + +
i
6.4 Width, B
+ + + + + + −
6.5 Locating features
+ + + + + − +
6.6 Lubricant feed and
+ + + + + − +
distribution features
6.7 Surface conditions + + + + + − +
Crush height, a
6.8 + − − − − − −
6.9 Free spread
+ + − − − − −
6.10 Straightness of sliding
+ − − − − − −
surface
6.11 Joint face taper, h + − − − − − −
∆
6.12 Back contact + − − − − − −
6.13 Joint displacement, B
− − + − − − −
∆
6.14 Height of thrust
− − − − − (+) +
half-washer, H
6.15 Flatness − − − − − (+) +
Flange diameter, D
6.16 + + + + + + −
fl
6.17 Distance between
+ + + + + − −
flanges, a
fl
6.18 Flange thickness, s
+ + + + + + −
fl
6.19 Perpendicularity
+ + + + + (+) −
(squareness) of flange
6.20 Geometric deviations
6.20.1 Cylindricity
− (+) − + − (+) −
6.20.2 Run-out of thrust face − (+) − + + (+) −
6.20.3 Coaxiality and − + − + + + −
concentricity
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ISO 12301:2007(E)
Table 2 (continued)
Type of plain bearing
Relevant
Thin- Thick- Thrust
clause/
Unsplit Solid
Quality characteristics
walled walled Wrapped Sintered washer
subclause
metallic polymer
half- half- (ring
bush bush
number
bush bush
bearing bearing and half)
a
7 Material quality characteristics
7.1 Metallic solid material
7.1.1 Hardness − + + + − − +
7.1.2 Material composition
− + + + − − +
7.1.3 Material structure
− + + + − − +
7.2 Metallic multilayer material
7.2.1 Overlay properties
+ + + − − − +
7.2.2 Lining properties + + + − − − +
7.2.3 Backing properties + + + − − − +
7.2.4 Adhesion (bond) of + + + − − − +
adjacent layers
7.3 Polymer layer material
7.3.1 Overlay properties − − + − − − (+)
7.3.2 Lining properties
− − + − − − (+)
7.3.3 Backing properties
− − + − − − (+)
7.3.4 Adhesion (bond) of − − + − − − (+)
adjacent layers
7.4 Solid polymer material
7.4.1 Material composition − − − − + − −
7.4.2 Material structure − − − − + − −
7.5 Sintered material
7.5.1 Material composition − − − − − + −
7.5.2 Material structure
− − − − − + −
a
Significance of symbols:
Plus sign indicates that the characteristic is generally applicable to the corresponding type of bearing.
Plus sign in parentheses indicates that this characteristic is not always applicable.
Minus sign indicates that the characteristic is not relevant for the corresponding type of bearing.
6 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
6 Geometrical quality characteristics
In order to assess plain bearing quality, important dimensional quality characteristics are specified in
Clause 6.
Unless otherwise stated, the dimensions in the tables and figures are given in millimetres.
6.1 Wall thickness, s
3
See Table 3.
Table 3
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/measuring
Applicability Test equipment
geometrical characteristic principle
NOTE This test method is also
Metallic See Figure 1.
applicable when measuring joint face
thin-walled
bore relief.
half-bearing
Figure 1 Figure 2
Metallic See Figure 1. Measured normal to the back Device for measuring wall
thick-walled surface in the radial direction thickness
half-bearing using the spherical faces of the
measuring pins
Wrapped See Figure 3 and Measure in accordance with Device for measuring wall
bush ISO 3547-7. ISO 3547-7. thickness (see ISO 3547-7)
Depending on the manufacturing
process, the back of the wrapped
bush can show slight hollows.
The wall thickness shall,
therefore, be measured outside
these hollows, i.e. on the
“bearing areas”
(see ISO 3547-7). In the cases
D < 8 or D > 150, the test
i i
method shall be subject to
agreement between the
manufacturer and user.
Figure 3
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ISO 12301:2007(E)
Table 3 (continued)
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/measuring
Applicability Test equipment
geometrical characteristic principle
Unsplit See Figure 4. Similar to Figure 2 Device for measuring wall
metallic thickness
bush
Figure 4
Solid polymer See Figure 4 Similar to Figure 2 Device for measuring wall
bush thickness
Measure normal to the back
surface in the radial direction
using the spherical faces of the
measuring pins.
Sintered bush See Figure 4. Similar to Figure 2 Device for measuring wall
thickness
Thrust washer Axial distance between the two Measure parallel to the axial Device for measuring wall
faces of the washer direction using the spherical thickness
(see Figure 5) faces of the measuring pins
(see Figure 6).
Figure 5 Figure 6
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ISO 12301:2007(E)
6.1.1 Line measurement (wall thickness)
See Table 4.
Table 4
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/
Applicability Test equipment
geometrical characteristic measuring principle
Metallic thin-walled half-bearing
Wrapped bush; See Figure 7 and ISO 3547-7. The thickness of the half-bearing or Device for measuring wall
unsplit metallic bush is measured continuously on thickness
Each measuring line distance, a ,
ch
bush one, two or three predetermined or
is specified from the beginning of
agreed measuring lines
the sliding surface or from the end
(see Figure 7).
face by adding the nominal value of
It can be necessary to modify the
the chamfer. This measurement
defined position of the measuring
may also be used for an unsplit
lines to avoid design features, such
bush.
as grooves, etc.
Key
1 measuring lines
a = 1,5
ch
Distance to Number of
Width measuring measuring
position lines
a
B M
ch
u 15
B/2 1
> 15 u 50
4 2
> 50 6 2
Figure 7
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ISO 12301:2007(E)
Table 4 (continued)
Dimensions in millimetres, unless otherwise stated
Definition of
measured Test method/
Applicability Test equipment
geometrical measuring principle
characteristic
The thickness of the
Metallic See Figure 7. Device for measuring wall thickness; for details see
thick-walled half-bearing is measured the following table.
Each measuring line
continuously on two
half-bearing
distance, a , is Wall Measuring pin Uncertainty of Radius of
ch
predetermined or agreed
thickness load measurement measuring
specified from the
measuring lines
N anvil
beginning of the
(see Figure 7).
sliding surface or
s u 10 0,8 u F u 1,5
± 0,001 5
3 pin
from the end face by In the case where s > 25, the
3 ± 0,2
3
10 < s u 25 1,5 < F u 2,5
adding the nominal test method shall be subject to ± 0,002
3 pin
value of the agreement between the
chamfer. manufacturer and user.
It can be necessary to modify
the defined position of the
measuring lines to avoid
design features, such as
grooves, etc.
Solid See Figure 7. The thickness of the bush is Device for measuring wall thickness; for details see
polymer measured continuously on the following table.
Each measuring line
bush one, two or three
distance, a , is Outside Measuring pin Radius of Uncertainty of
ch
predetermined or agreed
diameter load measuring measurement
specified from the
measuring lines
anvil
beginning of the
N
(see Figure 7).
sliding surface or
from the end face by It can be necessary to modify D u 150 0,8 u F u 1,5
3 ± 0,2
o pin
adding the nominal the defined position of the
± 0,005
value of the measuring lines to avoid
150 < D u 300 1,5 < F u 2,5
chamfer. design features such as
5 ± 0,2
o pin
grooves, etc.
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ISO 12301:2007(E)
6.1.2 Point measurement (wall thickness)
See Table 5.
Table 5
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/
Applicability Test equipment
geometrical characteristic measuring principle
Metallic See Figure 2.
thin-walled
half-bearing
Wrapped Wall thickness measured at determined According to ISO 3547-7 Device for measuring wall thickness
bush; measuring points; see ISO 3547-7
It can be necessary to
unsplit
modify the defined
metallic
position of the measuring
bush
points to avoid design
features such as
grooves, etc. This
measurement can also
be used for an unsplit
bush.
Metallic Wall thickness measured at determined It can be necessary to External micrometer with dial
thick-walled measuring points which are subject to modify the defined indicator
half-bearing agreement between the manufacturer position of the measuring
and user. points to avoid design
features such as
grooves, etc.
Solid Wall thickness measured at determined It can be necessary to Device for measuring wall thickness
polymer measuring points (see Figure 8) modify the defined
External micrometer with dial
bush; position of the measuring
indicator
sintered bush points to avoid design
features such as
grooves, etc.
Distance to
Number of
Width measuring
measuring lines
position
a
B M
ch
u 15
B/2 1
> 15 u 50 4 2
> 50 6 2
Figure 8
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ISO 12301:2007(E)
Table 5 (continued)
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/
Applicability Test equipment
geometrical characteristic measuring principle
Wall thickness measured at determined
Thrust The thrust washer is External micrometer with dial
washer measuring points (P) on measuring measured at measuring indicator
lines at a distance, a , from the inside
points positioned as
ch
Device for measuring wall thickness;
diameter of the washers, as shown in shown in Figure 9.
for details see the following table
Figure 9
It can be necessary to
modify the defined
position of the measuring Radius of
Measuring pin
measuring anvil
points to avoid design
load
features such as
N
grooves, etc.
0,8 u F u 1,5
3 ± 0,2
pin
Key
1 measuring points
a
For thrust half-washers, α = 80°;
for thrust washers, α = 120°.
Figure 9
12 © ISO 2007 – All rights reserved
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ISO 12301:2007(E)
6.2 Outside diameter, D
o
See Table 6.
Table 6
Dimensions in millimetres, unless otherwise stated
Definition of measured Test method/measuring
Applicability Test equipment
geometrical characteristic principle
Metallic Outside diameter of a metallic thick- Measured in the radial direction Measuring device
thick-walled walled half-bearing is measured as a between two flat parallel faces
Holding device
half-bearing pair in the free condition, determined of the measuring device
using Equation (1) (see Figure 10) (see Figure 11)
xx++05, x
()
312
D = (1)
o
2
Figure 10 Figure 11
Wrapped See ISO 3547-2 and 3547-5. In accordance with ISO 3547-5 In accordance with
bush ISO 3547-5
Unsplit Outside diameter of a bush measured Measured in the radial direction Measuring device
metallic in the free condition, determined as the between two flat parallel faces
External mi
...
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