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UDC 629.12
Ref. No.: ISO/R345-1993(E)
IS0
I N T ERN AT I ON AL O RG A N IZATl ON
FOR STAN DA RD IZATl O N
IS O R ECO M M EN DATI O N
R 345
SHIPBUILDING DETAILS
TESTS ON GALVANIZED STEEL WIRE FOR ROPES
1st EDITION
October 1963
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The copyright of IS0 Recommendations and IS0 Standards
belongs to IS0 Member Bodies. Reproduction of these
documents, in any country, may be authorized therefore only
by the national standards organization of that country, being
a member of ISO.
For each individual country the only valid standard is the national standard of that country.
Printed in Switzerland
Also issued in French and Russian. Copies to be obtained through the national standards organizations.
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BRIEF HISTORY
The IS0 Recommendation R 345, Shiybuilding Details-Tests on Galvanized Steel Wire
,for Ropes, was drawn up by Technical Committee ISO/TC 8, Shipbuilding Details, the Secretariat
of which is held by the Stichting Nederlands Normalisatie-instituut ("1).
Work on this question by the Technical Committee began in 1952, taking into account the
studies which had been made by the former International Federation of the National Standard-
izing Association (ISA), and led, in 1960, to the adoption of a Draft IS0 Recommendation.
In October 1961, this Draft IS0 Recommendation (No. 464) was circulated to all the IS0
Member Bodies for enquiry. It was approved by the following Member Bodies:
Australia Italy Switzerland
Belgium Netherlands Turkey
Czechoslovakia New Zealand United Kingdom
Finland Portugal U.S.S.R.
France Romania Yugoslavia
India Spain
Three Member Bodies opposed the approval of the Draft:
Germany, Japan, U.S.A.
The Draft IS0 Recommendation was then submitted by correspondence to the IS0 Council,
which decided, in October 1963, to accept it as an IS0 RECOMMENDATION.
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ISO/R 345 - 1963 (E)
IS0 Recommendation R 345 Octo ber 1963
SHIPBUILDING DETAILS
TESTS ON GALVANIZED STEEL WIRE FOR ROPES
1. SCOPE
The present IS0 Recommendation concerns the testing of galvanized steel wire for wire ropes for
shipping (see also IS0 Xecommendation R 346, Shipbuilding Details -. Galvanized Steel Wire
Ropes).
The zinc coating of steel wire ropes for shipping may, at the user’s request, be of grade A or
grade B, corresponding to difrerent minimum conditions as determined by the results to be
obtained from the tests set out below.
2. LIST OF TESTS
2.1 The zinc coating of wires should be checked by means of the following tests:
adhesion of zinc coating, see section 3, page 5;
mass of zinc deposited per unit of surface, see section 4, page 6;
continuity and uniformity of coating, see section 5, page 7.
The quality of the galvanized steel wire should be checked by means of the following tests:
2.2
simple torsion, see section 6, page 9;
reverse bending, see section 7, page 10.
3. TEST FOR ADHESION OF ZINC COATING
3.1 Test specimen
The test specimen consists of a piece of wire long enough to allow the test to be carried out
properly.
The test specimen is wound round a cylindrical mandrel so as to form ten close spirals.
The ratio between the diameter of the mandrel and that of the wire is shown in table 1 :
TABLE I. - Ratio between the diameter of mandrel and of the wire
Galvanizing Wires of diameter Wires of diameter
grades 0.3 to 1.45 mm 1.5 mm and over
l I I
I 4 I 6 I
I
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ISO/R 345 - 1963 (E)
3.2 Procedure
Winding should be carried out at as uniform a speed as possible and, in any case, not so
rapidly as to give rise to any noticeable overheating of the coating.
After winding on the mandrel of appropriate diameter, the outside surface of the spirals
should show no sign of peeling or of serious cracks in the zinc coating.
The zinc coating may therefore be considered as satisfactory if any small cracks, which
may be detected after examination with the naked eye, are such that it is not possible to
detach the zinc coating by simply rubbing with the fingers, the use of the finger-nail not being
allowed.
4. DETERMINATION OF MASS OF ZINC DEPOSITED PER UNIT OF SURFACE
4.1 General
The test consists in dissolving the zinc coating of a sample of wire of given dimensions in a
hydrochloric acid solution. The mass of zinc so dissolved is determined either by the dif-
ference in mass of the sample before and after dissolving the coating (gravimetric method),
or by measuring the volume of hydrogen released during dissolution of the coating (gas
volumetric method). By relating the mass of zinc determined in this way to the surface of
the sample measured after dissolving the coating, the mass of zinc deposited per unit of
surface is obtained.
The gas volumetric method is the easiest to carry out. In case of argument, however, the
gravimetric method, by accurately weighing the sample before and after stripping the zinc
coating, should be used as a check.
4.2 Test specimens
After carefully straightening the samples of wire, test specimens should be cut to a length
of
300 mm for wires of less than 1.00 mm diameter,
150 mm for wires 1 .O0 to 1.49 mm diameter,
100 mm for wires 1.5 to 3 mm diameter,
50 mm for wires of more than 3 mm diameter.
Care should be taken to see that these lengths are accurate.
4.3 Apparatus
The apparatus used is shown diagrammatically in the sketch hereunder and consists essen-
tially of the following elements:
(I) tube graduated at least in ml, with a tap
at each end,
(2) Jask whose lower nozzle is connected by a
rubber tube to the bottom of the gra-
duated tube,
beaker used for removing the samples.
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ISO/R 345 - 1963 (E)
4.4 Procedure
With tap b closed, the graduated tube and part of the flask are filled with hydrochloric acid
solution containing a suitable inhibitor, e.g. hexamethylene tetramine, antimony trichloride,
antimony trioxyde.
The level of the liquid in the graduated tube is raised in the graduated tube to just under the
tap a by raising the acid reservoir flask until the two levels are the same.
After introducing the test specimen of the wire to be tested, tap a is closed and the hydrogen
released by the action of the acid on the zinc coating accumulated in the upper part of the
graduated tube.
When hydrogen is no longer being released, the flask is lowered in relation to the graduated
tube so as to bring the levels of the solution in the tube and in the flask onto the same plane.
The position of the meniscus of the liquid in the tube then indicates the volume of hydrogen
released.
The remaining part of the solution contained in the graduated tube is collected in the flask
by placing the flask on the table and opening tap U.
Tap h is then opened so that the test specimen of the wire can be collected in the beaker.
This specimen is washed and carefully wiped before measuring its dimensions.
The test is made on one wire at a time, the temperature in the tube being held at 20 2 OC.
4.5 Expression of results
The result is determined after 10 tests.
If z =- mass of zinc deposited per unit of surface,
d = bare wire diameter in millimetres,
I = length of a test specimen of wire in millimetres,
x = mean number of millilitres (cubic centimetres) of hydrogen released during each
of the 10 tests.
we have
Where the barometric pressure (P) is known to be outside the limits from 740 to 780 mm,
P
the above formula should be multiplied by the factor
760 '
In practice, tables allow the mass of zinc per square metre of the surface of the uncoated
wire to be read directly as a function of the diameter of this wire and of the volume of
hydrogen released.
The masses to be obtained, expressed in terms of the diameters of the wires, are shown in
Table 2, page 9.
5. TEST FOR CONTINUITY AND UNIFORMITY OF COATING
5.1 General
The test consists of dipping a sample of the wire for a given length of time, one or more
times in succession, into a saturated solution of copper sulphate, which gradually dissolves
the zinc coating and thus reveals any defects in the continuity of this coating.
The fact that the rate of solubility of the coating in the copper sulphate solution varies very
appreciably according to the galvanizing process used prevents any other precise conclusion
as to the thickness of the coating or its particular qualities of resistance to various kinds of
corrosion. The dip test is intended only to reveal a serious eccentricity of coating or any
othe
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