4. Open the shut-off valve at the drainage connection of the oil separator tank and catch the
draining cooling oil.
5. Close the shut-off valve and replace the screwed sealing cap.
Draining the oil from the oil cooler
1. Position a receptacle beneath the oil drainage point for the oil cooler's cooling oil.
2. Unscrew the appropriate filler plug at the oil drain point
12
.
3. Open the corresponding shut-off valve in the connection box and catch any draining oil.
4. Open the shut-off valve at the drainage connection of the oil cooler and catch the draining cool‐
ing oil.
5. Close the shut-off valve and replace the screwed sealing cap.
Draining the oil from the airend
1. Position a receptacle beneath the oil drainage point for the airend's cooling oil.
2. Unscrew the appropriate filler plug at the oil drain point
10
.
3. Open the corresponding shut-off valve in the connection box and catch any draining oil.
4. Open the shut-off valve at the drainage connection of the airend and catch the draining cooling
oil.
5. Close the shut-off valve and replace the screwed sealing cap.
Draining the oil from the air pipe
The airend is connected with the oil separator tank via an air pipe (pressure pipe) which must be
separately drained of cooling oil.
1. Position a receptacle beneath the oil drainage point for the air pipe's cooling oil.
2. Unscrew the appropriate filler plug at the oil drain point
11
.
3. Open the corresponding shut-off valve in the connection box and catch any draining oil.
4. Open the shut-off valve at the drainage connection of the air pipe and catch the draining cool‐
ing oil.
5. Close the shut-off valve and replace the screwed sealing cap.
Performing final work steps:
1. Replace the plug in the oil separator tank filling port.
2. Close the doors.
Dispose of used oil and oil-contaminated working materials according to environmental pro‐
tection regulations.
Further information See chapter 10.5.2 for cooling oil filling.
10 Maintenance
10.5 Compressor Maintenance
No.: 9_9570 07 USE
Operator Manual Screw Compressor
M250 SIGMA CONTROL MOBIL
145