Screw air compressor series
1. Main propulsion
Main propulsion is the heart of screw air compressor. Main
propulsion’s capability affects directly the whole machine’s
working life and its economic operation. Also it costs 30% of the
whole machine. OLG screw air compressor series have the original
Germany main propulsions which are produced by world-famous
compressor manufacture.
Rotor of main propulsion is made of hammered steel and its
unsymmetrical lines are gained through two individual processing
steps. The first step is using special digital control rotor
milling machine to get perform. The second step is accurate
processing, using five-axis CNC rotor grinding machine to get firm
and accurate surface and the tolerance of grinding machine is 0.05%
of one inch. During the second step, negative rotor will get a seal
line. Just as its name implies, the seal line is to reduce
clearance between rotor and cylinder as well as lessen leak. The
seal line is just like piston ring of reciprocal compressor. After
being processed by machines, every rotor will be checked by
three-coordinate machine to insure the size accuracy. Rotors are
put into body after paring up and being marked. The body is made of
high mass cast iron with compact grain. After processing, bodies
also need to be done size test to insure accuracy. The noise of OLG
screw air compressor series is 64-65 db, which shows the operation
parts of compressor are made of high quality material and processed
accurately, thus cause little crash and vibration and rotors get
long work life. These actually reflect the high level of machine’s
design and processing. The work life of main propulsion is over 30
years under normal operation. Meanwhile, main propulsion is with
high efficiency. The best screw speed makes it able to save over 5%
energy sources, compared with similar products in market.
Mean Time between Failure and work life of main propulsion’s rotor
in a large degree are decided by the work life of axletree. Main
propulsion’s axletree is over loading axletree which is specially
designed by German company SKF. Its work life is more than 20%
longer than other ordinary axletrees and that can be over 100
thousand hours under normal operation.
2. Unique machine design
Dual duct structure is unique for Dong Fang screw air compressor.
The compressor is divided to two individual ducts by sound
insulation board set in the center of the case. One duct is from
fan directly to condenser and then to the exit. The other duct
begins from the back of main electric motor and goes to the exit
after cooling the electric motor. Therefore, there are two air
intakes at the back and two air exits at the top. Such structure is
able to make noise be sealed in case but not come out. Extreme low
noise of the whole machine makes Dong Fang screw air compressor
stand at the leading level for noise control in the industry.
The condenser of Dong Fang screw air compressor is at the top of
case and above draught fan. The sound insulation board at the
center makes cooling air blow to condenser directly without going
into the case to avoid the cold air to be heated up by electric
motor, main propulsion and oil cask and ensure low temperature of
inlet air to condenser. At the same time, dual duct air compressor
can work without air baffle which gets less resistance on intake
air and better efficiency for cooling. Condenser is designed to
work under 50℃ for a long time and can work stably under every
conditions.
Connection pipes of Dong Fang screw air compressor are all made of
hard stainless steel, unlike hosepipes and other soft pipes which
will cause leak of oil after being heated with age, these hard
pipes can make sure machine works for a long time without leak.
3. Electric motor
With protect level IP54, insulation level F, SKF heavy axletree
for electric motor is able to get more than 95% efficiency rate,
good insulation, 10% overload power and bear high temperature.
4. Drive way
90KW～450KW Dong Fang compressor series are applied with flexible
coupling directly. Electric motor is connected with gear case’s
flange to make sure drive system is ever at the center and get less
vibration. In such drive way, gears and rotors can avoid sudden
wallop to each other because of the rigidity rubber between them,
in despite of starting or stopping compressor suddenly. Flexible
coupling decreases the start-up moment and increases driving
efficiency. The drive way of electric motor/ flexible coupling +
gear case/main propulsion gives drive gears high accuracy.
5. High-quality shock absorption equipment
Main propulsion and electric motor is placed onto shockproof frames
which are welded by clamps and with good plane horizontal degree.
That makes sure each extension shafts of main propulsion and
electric motor are parallel at every direction, straps get few
jumpiness and finall
