Kobelco KNW Series, Инструкция по эксплуатации

Страница: 9 / 54

KIMA00H1 (0204) 5
1.3
Cooling
Air Flow
(Figure 4)
A separate electric motor driven fan draws ambient air into the cabinet
through screens in the back panel. The screens are equipped with
dust filters. The air takes one of two flow paths. The first passes
directly through to the aftercooler and exhausts through the top of the
enclosure. In the second path, air enters near the motor, cools the
compressor motor and passes into the compressor section of the
cabinet. The air then goes through both the intercooler and oil cooler
which are mounted side by side. The fan draws all the air through the
exhaust chamber and out the top of the enclosure.
When the compressor unloads, hot air is discharged through the
bleed-off silencer, pulled through the fan and exhausted. A
temperature switch shuts down the compressor if the air temperature
inside the cabinet exceeds 150°F (65°C).
1.4
Lubrication
Oil Flow
(Figure 5)
Oil for bearing and gear lubrication is stored in a sump, in the lower
section of the main gear case/compressor housing. A sight glass,
located on the side of the oil sump, is used to monitor the oil level.
Lube oil is drawn from the sump by a separate motor driven oil pump.
An oil pump discharge relief valve is provided to maintain a constant
pressure for component lubrication by relieving excessive pressure
back to the suction of the pump.
Oil leaving the pump is cooled to approximately 28°F (15°C) above
ambient air temperature in the oil cooler and is then filtered before
entering an oil gallery on the rear of the compressor first stage. A
portion of the lube oil passes through a tube to an oil gallery on the
rear of the compressor second stage. Lube oil flows from the oil
galleries to the front of each stage to lubricate and cool the front
bearings and drive gears. Lube oil passes through internal passages
from the galleries to lubricate the rear bearings and the timing gears.
All lube oil drains back into the sump.
The lube oil circuit is monitored with the following discrete devices:
a. Sump oil level indicator.
b. Lube oil filter differential switch.
The Programmable Logic Controller, PLC, (ref. Section 5.2) monitors
the lubrication circuit for the following:
a. Lube oil pressure
b. Lube oil temperature
The oil temperature is displayed on the GT Terminal. The PLC
monitors the lube oil temperature. A warning is provided as the
temperature approaches the recommended maximum operating
temperature, and a shutdown if it reaches the limit. The lube oil
pressure is monitored for alarm shutdown if the oil pressure is too low
while the compressor is operating.