Varian HS452, Инструкция по эксплуатации

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TECHNICAL INFORMATION
SECTION I
TECHNICAL DESCRIPTION
The HS452 and HS652 pumps are rotary vane
pumps oil sealed, driven by a three-phase electric
motor.
These vacuum pumps are suitable for pumping
non corrosive gases.
The main features are:
-
all parts in direct contact with the fluid pumped
are free of copper alloys;
- all materials are carefully selected to provide
extended life;
- a high capacity gas ballast device allow to
pump condensable vapors;
- all the parts composing the pump are fully re-
placeable due to the close machining toler-
ances and to the centering obtained by using
reference pins;
- due to its design features and low number of
gaskets, the pump requires little maintenance,
disassembly and reassemble are easy and
require minimal time.
The pump works with force-feed lubrication, pro-
vided by an auxiliary gear-pump driven by the rotor
of the vacuum pump itself. This ensures proper lu-
brication even when pressures are close to at-
mospheric.
The entire pump functional block is immersed in
the oil contained in the casing. The oil guarantees
perfect sealing of the discharge valves, enters the
pump to ensure lubrication and sealing of the parts
inside, facilitates heat dissipation and reduces
pump noise.
The pump is equipped with a special anti-
suckback device which automatically isolates the
vacuum system when the pump stops. This avoids
rises in pressure or oil flow in the vacuum system
while air is allowed back into the stator chambers.
The air entering the pump after the anti-suckback
device has closed prevents the oil in the casing
from filling the stator chambers.
The inner seals are achieved by the lubricating oil,
thanks to the close machining tolerances.
The vacuum pumps are connected directly to the
electric motor through a flexible coupling, so that
motion is transmitted even in case of poor align-
ment.
A fan fitted on the joint and housed in the pump
support produces a forced air flow over the finned
surfaces of the casing to avoid oil overheating.
LUBRICATION
The pump’s lubricating system is force-feed type.
Oil circulation is obtained by means of a gear
pump connected to the rotor shaft.
The oil is drawn through a gauze filter to prevent
any foreign bodies from entering the pump.
Shunt-mounted on the delivery line is a hydraulic
piston which, besides actuating the anti-suckback
device (see
ANTI-SUCKBACK DEVICE ), also
regulates pressure by discharging excess oil flow
directly into the tank.
The required flow of oil under pressure passes
through ducts that are drilled in the walls of the
pump and lubricates the bushings and the inside
parts.
9 87-900-978-01(D)