LEYBOLD E 250 - 3.6 Pump Disassembly and Reassembly; 3.6.1 Preparations for Disassembly

GA 02.200/8.02 - 10/02
Maintenance
16
3.6 Disassembling and
Reassembling the Pump
This kind of work should be left to trained
personnel. At this point we recommend our
practical training courses.
Please note especially the safety informati-
on given in Chapter 3 on page 13.
3.6.1 Preparations
- Wear suitable protective clothing.
- There exists the danger that someone
may slip on spilt oil.
- Ensure compliance with the relevant
safety and environmental regulations.
- Please note especially the safety infor-
mation given in Chapter 3 on page 13.
Disconnect the motor.
Drain the oil (see Section 3.3).
Remove the pump from the vacuum system.
Place the pump in an oil pan to catch any residual oil
from the pump during disassembly.
3.6.2 Disassembling the Valves and Oil
Level Glass
Remove the exhaust box (7/5).
Unscrew the T-screw connections (8/6), tubing (8/8) and
adaptor for the gas ballast (8/5).
On single-stage pumps, each pumping chamber has an
exhaust valve and a gas ballast valve with tubing. On
two-stage pumps, each pumping chamber has an
exhaust valve, but only the second stage has a gas bal-
last valve.
Unscrew the valve holder (8/4) (special tool 9) and remo-
ve the exhaust and gas ballast valve assembly (8/3).
Disassemble the oil-level glass (8/2) only if it is very dirty
or damaged or has a leak. It can be unscrewed using a
socket screw wrench.
Warning
Warning
Torque for the screws in Nm
Pinion gear mount M 10 x 35 55 Nm
Exhaust valve M 8 x 50 30 Nm
Casing lid
- left M 8 x 30 30 Nm
- at the motor M 8 x 25 30 Nm
Exhaust box M 8 x 25 30 Nm
Casing lid (DK) M 8 x 20 30 Nm
Gear box M 8 x 50 30 Nm