Wire Ropes, Elements and Definitions - Wire Ropes: Tension, Endurance, Reliability - page 5

Table 1.2 Surface-related mass of zinc coating (excerpt of EN 10 244-2)
Wire diameter (mm) Class

A (g/m 2 )

AB (g/m 2 ) B (g/m 2 ) C (g/m 2 ) D (g/m 2 )

0.20 B d \ 0.25 30 20 20 20 15

0.50 B d \ 0.60 100 70 50 35 20

1.00 B d \ 1.20 165 115 80 60 25

1.85 B d \ 2.15 215 155 115 80 40

2.8 B d \ 3.2 255 195 135 100 50

4.4 B d \ 5.2 280 220 150 110 70

5.2 B d \ 8.2 290 - - 110 80

of class A can be used, as for example A 9 3. A surface-related zinc mass of
100 g/m 2 means that the thickness of the zinc layer is about 0.015 mm. For the
Zn95Al5 coating, EN 10244-2 provides nearly the same surface-related mass for
the classes A, B and AB. Unlike EN 10244-2, in Table 1.2 and in the following the
symbol d is used for the diameter of the wire.

1.1.4 Corrosion Resistant Wires

In exceptional cases corrosion resistant wires (stainless steel) have been used as
rope wires. Some corrosion resistant steels for wires are listed in Table 1.3 from
prEN 10088-3:2001. The steel names of these high alloy steels begin with the
capital letter X. The following number gives the carbon content in % multiplied
with the factor 100. Then the symbols and the contents in % of the alloy elements
are given. For example, for the steel X5CrNiMo17-12-2 the contents are 0.05 %
carbon, 17 % chromium, 12 % nickel and 2 % molybdenum.
Corrosion resistant wires for ropes have an austenite structure. Because of this
structure they cannot be magnetized which means that the highly effective mag-
netic method of testing cannot be used to inspect the ropes. It should also be taken
into consideration that these steels are not corrosion resistant in all environments.
Like non-alloy carbon steel wires, corrosion resistant steel wires are produced
by drawing. The strength range stated in Table 1.3 is valid for drawn wires with a
diameter C0.05 mm. From the different corrosion resistant steels available usually
those of medium strength are used. Corrosion resistant wire ropes running over
sheaves are not usually as durable as those made of non-alloy carbon steel.

1.1.5 Wire Tensile Test

The tensile test is standardised according to EN 10002-1. The main results of the
tensile test provide the measured tensile strength R m and the total extension e t .Itis
not possible to detect precisely the limit where the yielding of the wire begins.