ISO 3512:1976

INTERNATIONAL STANDARD 3512
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION *MEX’3L H4POJlHAR OPrAHMlAUMR no CTAHüAPTM3AUHH .ORGANISATION INTERNATIONALE DE NORMALISATION
Heavy duty cranked link transmission chains
Chaînes de transmission à maillons coudés de haute résistance
First edition - 1976-02-01
UDC 621.855 Ref. No. IS0 3512-1976 (E)
Descriptors : chain drives, cranked link chains, specifications.
*
Price based on 7 pages

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FOREWORD
IS0 (the International Organization for Standardization) is a worldwide federation
of national standards institutes (IS0 Member Bodies). The work of developing
International Standards is carried out through IS0 Technical Committees. Every
Member Body interested in a subject for which a Technical Committee has been set
up 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.
Draft International Standards adopted by the Technical Committees are circulated
to the Member Bodies fbr approval before their acceptance as International
Standards by the IS0 Council.
International Standard IS0 3512 was drawn up by Technical Committee
ISO/TC 100, Chains and chain wheels for power transmission and conveyors, and
circulated to the Member Bodies in October 1974.
It has been approved by the Member Bodies of the following countries :
Austria India Turkey
Italy United Kingdom
Belgium
Japan U.S.A.
Bulgaria
Romania Yugoslavia
Finland
France South Africa, Rep. of
Germany Sweden
The Member Bodies of the following countries expressed disapproval of the
document on technical grounds :
Australia
Czechoslovakia
O international Organization for Standardization, 1976 O
Printed in Switzerland

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INTERNATIONAL STANDARD IS0 3512-1976 (E)
Heavy duty cranked link transmission chains
1 SCOPE AND FIELD OF APPLICATION 2.3 Dimensions
Chains shall conform to the dimension given in tables 1 and
This International Standard specifies dimensions,
1M. Maximum and minimum dimensions are specified to
tolerances, measuring loads and minimum breaking loads,
ensure interchangeability of links as produced by different
together with the tooth gap forms and rim profiles of the
makers of chain. They represent limits for inter-
associated chain wheels, for cranked link1 ) roller chains
changeability, but are not the actual tolerances that
suitable for the mechanical transmission of power and allied
applications under onerous conditions. should be used in manufacture.
The dimensions of chain specified ensure complete
Pitch p is a theoretical reference dimension used in
interchangeability of- any given size and provide
calculating strand lengths and chain wheel dimensions; it is
interchangeability of individual links of chain for repair
not intended for inspection of individual links.
purposes.
2.4 Breaking loads
2 CHAINS
The test length shall have a minimum of three free pitches.
2.1 Nomenclature
The ends shall be attached to the testing machine shackles
by a pin through the plate holes or the bushes. The shackles
The illustrations shown below and in the key to tables 1
shall be so designed as to allow universal movement; the
and 1M do not define the actual form of the chain plates.
actual method to be used is left to the discretion of the
manufacturer.
2.2 Designation
Heavy duty cranked link roller chains are designated by the Tests in which failures occur adjacent to the shackles shall
standard IS0 numbers given in tables 1 and 1M : the first be disregarded.
two digits express the pitch in eighths of an inch, while the
second (last) two digits express the bearing pin diameter in The minimum tensile breaking loads shall be those given in
sixteenths of an inch. tables 1 and 1M.
"7 7
Cran ked
1
' Connecting pin
Retaining pegA
(schematic)
FIGURE 1 - Cranked link chain assembly F I GU R E 2 - Typical cranked link components
1) In the U.S.A., the term "offset sidebar" is used in place of ''cranked link".

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~
6
IS0 3512-1976 (E)
I l I
Offset construction
straight crank
~
I
I
I I
I Offset construction
radiused crank
I
FIGURE 3 - Key to tables 1 and 1M

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IS0 3512-1976 (E)

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U
IS0 3512-1976 (E)
3.2 Diametral dimensions of wheel rim
2.5 Length accuracy
Finished chains shall be measured either dry or after only
3.2.1 Nomenclature
light lubricating.
The standard nominal length for measurement shall be that
nearest to 3 048 mm (120 in).
I
The chain shall be supported throughout its entire length
and the measuring load given in tables 1 and 1 M applied. To
comply with this International Standard, the length shall be
P
the nominal length subject to the limits of tolerance
3
of i- 0.32 %
o.
Even numbers Odd numbers
The length accuracy of chains which have to work in
of teeth of teeth
parallel shall be within the above limits but matched by
agreement with the manufacturer.
FIGURE 4 - Diametral dimensions
c = chordal pitch, equal to chain pitch
p
2.6 Working clearances (see figure 3)
dR = measuring pin diameter
The form of the line of cranking, or offset, across the width
z = number of teeth
of the link may be curved or straight.
d = pitch circle diameter
If straight, the distance from the pitch point is Il or I*.
df = root diameter
MR = measurement over pins
If curved, this distance is I, or I,. Radii I, and /6 shall be
sufficient to allow clearance over the adjacent plate nose
3.2.2 Dimensions
contained by the clearance radii I, and I, during chain
articulation round a seven-tooth wheel.
3.2.2.1 PITCH CIRCLE DIAMETER
Side plates may be extended, provided that the extension is
d= - (see the annex for nominal dimensions of the
within a 30" included angle with respect to the sidebar, as
180"
sin -
indicated in figure 3. The chain link construction shall
Z
always allow for this extension to be adopted.
normal range of teeth)
3.2.2.2 MEASURING PIN DIAMETER
+ 0,Ol rnm
2.7 Marking
dR = dl (see 3.3.1) subject to tolerance limits
+ 0.000 5 in
The chain should be marked with
O
a) the manufacturer's name or trade mark;
3.2.2.3 ROOT DIAMETER
b) the IS0 number (see 2.2).
df = d - dl subject to the following tolerance limits :
Root diameter Tolerance for machined teeth
3 CHAIN WHEELS I
O O I
df Q 305 mm (12 in) I -0.38rnm (-0,015inI
I
3.1 Nomenclature
O
df Q 1 215 rnm (48 in)
Io - 0.50 rnrn 1- 0,020 in)
I
The nomenclature for basic chain dimensions on which all
wheel data are based will be found in the keys to tables 1
O
df > 1 215 rnm (48 in)
- 0.77 mm 1- 0,030 in)
and IM. Chain wheel nomenclature is covered under the
Io
respective headings.
4

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IS0 3512-1976 (E)
with the corresponding working faces of the respective
Tolerance for non-machid
teeth.
R
...