Gardner Denver Reavell H5000 Series, Руководство оператора

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GENERAL DESCRIPTION AND OPERATION
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4.7 RUNNING GEAR
Big and small end bearings along with main bearing bushes are all replaceable.
4.8 VALVES
Both stage valves are of the flat, low lift, multi-ported type and combine suction and delivery functions. All
valves are easily accessible for maintenance and replacement when required.
One valve cover per cylinder and good flow characteristics are a feature of this valve design.
4.9 INSTRUMENTATION
Pressure gauges are fitted to both stages together with an oil pressure gauge and low oil pressure
switch.
A temperature cut-out switch is fitted to the first stage delivery before cooling. This monitors the
temperature to provide a signal to the starter to shut down the compressor in the event of the set point
being exceeded. High temperature can result from the effects of valve leakage and reduced water flow.
4.10 DELIVERY UNLOADING AND CONDENSATE
The heart of the unloader/drain system is the diaphragm valve. When the compressor is stationary, these
valves – one connected to each separator – are open. About 10 seconds after the compressor starts, the
solenoid valve opens and allows first stage pressure to pass to the diaphragm valves, closing them.
Pressure then builds up in each stage.
When the compressor stops, the solenoid valve is de-energized, shutting off the first stage air supply.
The stage pressure can then open each valve, discharging air and any collected condensate. The
compressor is then unloaded ready for the next start.
If air is wet and the compressor runs more than thirty minutes without stopping, a timer in the motor
starter can be used to de-energise the solenoid valve for about five seconds to allow collected
condensate to be dumped.
4.11 AUTOMATIC STOP/START CONTROL
The motor starter is normally controlled by a pressure switch which is supplied loose for fitting to
customer's storage system. When the pre-selected low pressure is reached, the contact closes, initiating
the start up of the motor. On reaching the high pressure, contact opens, thus stopping the motor. The
control circuit in the starter will operate the unloaders as described above.