Superior spx 960, Instruction Manual For Operating And Maintenance

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Istruction Manual for Operation and Maintenance
SPX-960
:
5.2.2 WIRE ROPE CORROSION
Alike wear, wire rope corrosion will eventually lead to breakage. However, corrosion is to be considered as
a more dangerous factor than wear considering the same diameter reduction of the wire rope. The same
rules as wear apply for corrosion, but they must be adopted with greater care.
Internal wire rope corrosion can be highlighted by a reduction in the total diameter of the rope.
5.2.3 OTHER POSSIBLE CAUSES OF WIRE ROPE DAMAGE
The wires in the ropes are subjected to “hammering” effects when contacting the elements on which they
wind (pulleys, drum) as well as mutual pressure which is sometimes quite high. These two types of stress
can lead to quick wire wear which can eventually result in local breakage. Wire ropes are also subjected
to torsional and longitudinal vibrations which stress the material and eventually lead to rope breakage.
5.2.4 WIRE ROPE REPLACEMENT
WARNING
The decision to replace the wire rope depends on the following factors:
• number of broken wires and their position;
• lever of wire rope wear;
• lever of wire rope corrosion;
• other damage or alterations generated by wire rope condition.
The wire rope must be replaced in the following cases:
- the reduction in total wire rope diameter is equal to 10% of the original diameter, regardless whether it
is in one point only;
- a strand is completely broken and is damaged to such extent that its useful section has been redu-
ced by approx. 40%;
- the wire rope is dented, twisted or bent permanently due to damage or contact with sharp edges;
- the core comes out the wire rope (even in one point only);
- one strand (or more than one strand) are slackened or protruding from the wire rope.
We however need to point out that wire rope breakage is dif
fi cult to identify because the end of a broken
wire remain in their original position and do not protrude on the rope surface.
To identify broken wires, the grease covering the rope must be removed and the rope must be bent by
hand so that the ends of broken wires can come out.
5.2.5 WIRE ROPE INSPECTION
DANGER
The wire ropes must be checked by qualifi ed personnel every 300 hours of operation, who must
write the results in the supplied forms.
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MAINTENANCE