Nederman NCF 30/15, Руководство пользователя

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NCF fan
EN
2.2.1 Mechanical characteristics risks
The following is a list of specific hazards related to the
fan’s mechanical characteristics.
WARNING! Risk of personal injury
A person may receive injuries as a result of:
• Vibrations and noise emission are directly
correlated. Compliance with the instructions
given for correct installation so as to reduce
vibrations to a minimum is of equivalent im-
portance for noise reduction.
• Avoid positioning fans in areas that could in-
crease the noise risk.
• Avoid working positions that increase the
noise risk for operatives.
• Reducing exposure times and the use of Per-
sonal Protection Equipment will reduce the
risks caused by exposure to noise emissions.
See
Figure 1 .
• With sound pressures higher than 100 dBA,
operatives may approach the fan only if it is
not operating, even if wearing Personal Pro-
tection Equipment.
2.2.2 Environmental risks
The fan is designed to operate in and to withstand or-
dinary conditions of working environments.
The presence of the following can affect the life span
of components, causing premature deterioration,
above all with respect to guards:
• Vibrations
• Corrosive agents (dust, gas, fumes, mist)
• High temperatures
• Condensation
• Solid bodies
• Abnormal turbulence
• Currents of air
• Voltage differences due to installation
Since it is impossible to establish all-inclusive criter-
ia that can take into account all the possible combin-
ations of these effects, it is advisable to implement
a plan of periodical checks according to the effective
deterioration noted, so that any variations in struc-
tural characteristics can be detected in subsequent
checks.
2.2.3 Vibration risks
CAUTION! Risk of equipment damage
• Failure to check vibration levels may gener-
ate high risk factors and compromise the op-
erative lifespan of the fan.
• Fan operation within a very broad range of
operating speeds may lead to increased vi-
bration in correspondence with a specific res-
onance frequency of the system of which the
fan is only a single component.
• Avoid working at speeds coinciding with
structural resonance frequencies, and if this
is not possible, modify some variable that can
change the resonance frequency of the sys-
tem, for example by using vibration dampers
of a different type.
Vibrations are the main factor affecting the opera-
tional life and safety of fans, and for this reason it is
essential to accurately monitor their level during fan
operation and work cycles.
If ignored, vibrations can:
• Cause the formation of cracks serious enough to
cause structural failure, which may even be sudden.
• Cause difficult operating conditions for bearings,
with malfunctions that may even include seizing
(with dangerous overheating effects).
• Cause slackening of tightening and fixing compon-
ents (nuts and bolts).
• Generate greater noise.
NOTE!
The monitoring of vibrations and temperat-
ures makes it easier to take preventive actions
against accidents.
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