Tuthill KINNEY 850D, Operator'S Manual

Page: 12 / 38

12
PROPER VENTING
The vacuum pump must be properly vented to ensure all oil is removed from the pumping chamber before
the pump is turned off. Also, the suction line must be properly vented to ensure oil does not migrate into the
process chamber.
Recommended vent valve sizes:
KT-150 = .75 inch KT-300 = 1.0 inch
KT-500 = 1.5 inches KT-850 = 2.0 inches
The vent valve must be open for at least 10 seconds before the pump is turned off to remove all oil from
the pumping chamber.
DISCHARGE MANIFOLDING
Discharge manifolding should be sized and
designed to prevent the following:
• Return of oil mist condensate to the
pump
• Oil loss
• Oil mist in the discharged gas.
• Under the normal conditions, the
diameter of the manifolding should not
be less than the diameter of the pump
connection and pipe length should be
kept to a minimum to avoid increased
back pressure.
The installation of an oil mist eliminator
on the discharge is recommended for all
applications, (as shown in Figure 4). Oil
which collects in the eliminator should be
returned to the pump. The oil return kit will
drain oil back into the separator housing
when the pump is operating at low pressure
or when the pump is stopped. If the pump is
to operate continuously, or normal operating
pressure is between 10 torr (13 mbar) and
150 torr (200 mbar), the oil return should
be connected to the gas ballast as shown
in Figure 3. Over 150 torr (200 mbar) the
oil return should be connected to the pump
inlet.
It may be necessary to pipe the pump exhaust
fumes away from the pump area, such as
outdoors. If this is done, the piping must be
arranged to prevent line condensation from
returning to the pump. A flexible connector
should be fitted in the discharge line to
provide freedom for the vibramounts.
Figure 3 - Oil Return to the Gas Ballast Valve
DISCHARGE
OIL
MIST
ELIMINATOR
OIL
RETURN
LINE
GAS
BALLAST
ASSEMBLY
OME DISCHARGE
CONNECTION
FIBER OUTER
SHELL (ELEMENT)
SATURATED
ZONE
OIL COLLECTS
AT BOTTOM
PRESSURE
GAUGE OR
PRESSURE
RELIEF VALVE
FIBER INNER
SHELL
(ELEMENT)
ALTERNATIVE TO THE
PUMP OIL RESERVOIR
OR GAS BALLAST
VALVE
OIL DRAIN
CONNECTION
OIL DRAIN
CHECK
VALVE
TOP COVER
GASKET
OIL MIST
FROM THE
PUMP (1)
OIL RETURN
CONNECTION
Figure 4 - Oil Mist Eliminator