Oerlikon 10926, Operating Instructions Manual

Page: 6 / 44

6 GAET02307_002_10 - 06/2008 - © Œrlikon Leybold Vacuum
Description
However, in that case, the pump will not reach anymore its specific end
pressure. That will often indicate that oil is polluted and/or oil filter is clogged.
A fan running on the motor shaft generates the necessary cooling air.
The oil is also fed, thru a cooling coil.
Upon request, water cooled with heat exchanger and thermostatic valve can
be delivered. Those pumps are delivered with a dedicated instruction manual
adder.
Pump can be ordered with gas ballast device, on request (6/14). By opening
the gas ballast valve, a controlled amount of air so called "gas ballast" - is
admitted into the pump chamber.
This gas ballast prevents condensation (up to the limit of water vapor
tolerance specified in the Technical Data) when pumping condensable gases
or vapo
u rs.
There are different types of gas ballast:
- standard gas ballast < 7 Nm
3
/h,
- large gas ballast 18 Nm
3
/h,
- gas ballast with electromagnetical valve 24 VDC, 18W, 7 Nm
3
/h.
The operational limits of gas ballast are defined in § 4.1.
On pumps supplied without gas ballast valve, the valve can be retrofitted
(see § 1.4 and 4.4).
Unintentional venting of the vacuum chamber as well as oil suckback when
shutting down the pump are prevented by the integrated antisuckback valve
(7/54), see also § 4.2.