misia XM SERIES, Инструкция по установке, эксплуатации и обслуживанию

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54
ELECTRIC WIRE ROPE HOIST
XM SERIES
4.7.2 PERIODIC MAINTENANCE
Periodic maintenance includes steps performed
by trained staff and concerning adjustments and
lubrications. During the maintenance of mechanical
and electric components, switch-off the main isolating
switch and place an "out of service" notice on the
hoist.
For the single components of the equipment,
observe the following instructions:
Ropes and fasteners - Check the condition
of the rope to judge the possible deterioration.
The rope and rope guide are wearing parts,
regular lubrication makes their life longer. It is often
possible to improve the performance of the ropes
finding out the causes of their deterioration. This can
be done analysing the old rope. During the inspections
it is advisable to carefully observe the parts of the rope
coiled on the pulley and the fixing point at the end. Note
the date and the results of the checks as prescribed in
the relevant table, in order to be able to plan when
the rope is to be replaced. The decision to replace the
rope according to the UNI ISO 4309/84 must be taken
first of all considering the number and the location
of broken strand wires, by the degree of wear and
corrosion, by other important damages or tears. The
ropes must be replaced when visible broken wires
reach the maximum deterioration values given for one
of the two reference lengths (Table 9), corresponding
to 6 or 30 times the rope diameter. Keep in mind that
breaks often are hard to identify, since the ends of the
broken wire remains in the original location, without
protruding from the surface of the rope. To see these
breaks, it is necessary to remove the grease covering
the rope, to slide a piece of solid wood along the rope
and, if possible, to bend the rope manually, in order
to force the wires ends to raise making themselves
visible. The rope check must be performed "without
load", to ease the visualisation of possible breaks and
to foresee a bending radius roughly corresponding to
the pulley radius.
Checks during the inspection:
Number of broken wires - Based on the
features of the rope, it is possible to find out
in Table 9, "Limit number of visible broken
wires", the maximum permissible number of visible
wire breaks on any rope section. In case of higher
values, than those shown, the rope must be replaced.
Rope diameter decrease - if a wire core rope
shows a decrease of 15% or more of its rated
diameter (due to stretching in the bending
area), it must be replaced.
Rope corrosion and wear - In the event of
a decrease of 10% or more of the rated rope
diameter due to corrosion or wear, the rope
must be replaced even in the absence of broken wires.
Rope deformation - Helical deformations
with diameter decreases concentrated in a
short section of the rope and local flattening or
angular deformations due to severe external causes.
in the first case, the deformation causes irregular
movements of the rope while it is running, which are
the primary cause of greater wear and wire breaks; in
the second case, the defect often occurs at the rope
sockets.
Heat influence - Ropes exposed to
exceptionally high temperatures (externally
shown by the annealed iron colour assumed
buy the rope) must be replaced.
The above causes are described in detail in the
ISO standards 4309.
Hook - Verify the function of the safety catch
and of the rotation lock.
Check the deflection pulleys of the rope for
smooth rotation.
The pulleys of the hook can be easily visually checked
observing the inclination without load during lifting and
subsequent lowering. If the hook during these travels
shows a considerable inclination, first on one side and
then on the other, from the vertical, this means that
the pulley friction is excessive and the pulley must
therefore be disassembled to check their running
surfaces. With released rotation lock check the wheel
for smooth running, without too much friction and jolts.
Otherwise remove it and check the bearing. Check the
area in contact with the slings for wear.
Check the hooks for cracks or bends. To measure
bending, measure the distance between the stem and
the point of the hook as shown in the figure. If the
measured value is 5% higher than the value originally
measured on the new hook (a) according to table DIN
15401, we recommend replacing the hook.
a
4. OPERATION AND MAINTENANCE INSTRUCTIONS