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5.1 TF (Fusibile Plug) OPERATION AND REPLACEMENT
5.1.1 EXPECTED DEVICE OPERATION
The TF are calibrated for different triggering temperatures, which may be inferred
from the marking and they are characterized by different identification colours.
The Fusible Plug is a device designed for safeguarding the hydromechanic coupling.
It is composed of a bored plug, filled with a pad in hot-melt material, which melts when
temperature reaches the threshold
In case of abnormalities, due to an excessive slip and subsequent overheating of the
transmission fluid, the melting of the pad and the transmission oil leakage occur, so that
the power transmission to the driven machine is cut off
CAUTION
The transmission oil leakage prevents the lubrication of the internal
bearings; therefore the activation of this device MUST ALWAYS be followed
by the automatic shutdown of the motor and the drive end.
DANGER OF OVERHEATING, SEIZURE AND/OR FIRE IGNITION.
5.1.2 TF REPLACEMENT
After this device has triggered causing the shutdown of the machine, where the fusible
plug is installed, it is necessary to replace the TF as described below:
- Wait for all moving components to stop.
- Cut out power supply to motor or drive end and apply an appropriate safety
padlock.
- Wait for the cooling down of the hydromechanic coupling (max 40°C) before
intervening.
CAUTION
Remove any oil dripping or leakage from the coupling or the soil.
DANGER OF SLIPPERY FLOOR, CRASH AND/OR FALL.
- Open the guard to access the hydromechanic coupling.
CAUTION
Do not install the TF on ATEX hydromechanic couplings category 2.
DANGER OF FIRE IGNITION.
- Replace the fusible plug with a spare part having the same triggering
characteristics and fill the coupling with suitable transmission oil as described
in section 6.3 FILLING AND CALIBRATION OF HORIZONTALLY MOUNTED
COUPLINGS or 6.4 FILLING AND CALIBRATION OF VERTICALLY MOUNTED
COUPLINGS.
- Remove the causes, which have determined the device triggering due to over-
heating.
- Check the shaft for oil leakage and the condition of the shaft sealing.
- Remove any tools, cloths and/or foreign bodies from the coupling and the
working area.
- Close the guard in the hydromechanic coupling operating area.
The replacement of the TF is thus ended.
TRIGGERING TEMPERATURES
COLOUR
96°C
BLUE
120°C
WHITE
145°C
RED
180°C
GREEN
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