US VACUUM Torrvac Series, Installation & Operation Manual

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START-UP
Check rotation of the motor as described previously under POWER REQUIREMENTS. Fill the pump
with oil as described previously under OIL FILLING. Start the pump and immediately close the inlet, Run
the pump for a few minutes before checking the oil level again. With the pump shut off, the oil level
should be visible in the oil sight glass between the “MIN” and “MAX” mark.
Add oil, if necessary, but only add it when the pump has been shut off and the circulating oil has had
sufficient time to return to the oil sump.
OIL SUCKBACK LINE
The TorrVac “B” series pumps are equipped with an oil suckback line w/ valve to return coalesced oil
back to the pump module. The primary function of the valve is to adjust the vacuum level the pump will
obtain while also allowing for oil to be returned back to the pump. The valve is set to allow the pump to
produce a vacuum of 10 Torr (29.5” Hg), if a higher vacuum is required then close the valve until the
required process vacuum is obtained.
The suck-back line is located underneath the exhaust port and extends back to the inlet flange of the
Pump
PROCESS GAS
The TorrVac pump is designed to pump air and are not intended for use when water vapor is being
pumped. In some applications, when the quantity of water vapor is moderate, TorrVac pumps have been
used with good results. In these situations, the pump is run until it is up to operating temperature before
it is allowed to pump process gas. The pump is also operated for a period of time off process and on air
(to clear it of process gas) before it is shut down. This procedure prevents vapor from condensing in the
pump. Before attempting to pump a gas laden with water vapor, contact U.S. Vacuum engineering for
advice.
STOPPING THE PUMP
To stop the pump, turn ff the power. The pump has a built-in anti-suck-back valve to prevent the pump
from rotating backwards when it is shut down. Install a manual or automatic valve or check valve in each
pipe leading to the pump when multiple pumps are pumping on a common header.
OXYGEN SERVICE PUMPS:
Do not use TorrVac pumps in oxygen enriched applications that is identified as any application which
has a process gas that is 25% or more oxygen.
IMPORTANT
THE PUMP SUCK-BACK VALVE IS FACTORY SET AT 29.5”Hg. IF THE PUMP IS
GOING TO BE OPERATING AT A VACUUM LEVEL ABOVE 29”Hg (ie: 15-28”Hg),
THE NEEDLE VALVE ON THE SUCK-BACK LINE NEEDS TO BE OPENED UP
TO THE FULL OPEN POSITION (COUNTER CLOCKWISE).
FAILURE TO PROPERLY SET THE SUCKBACK VALVE CAN LEAD TO PREMATURE
PUMP WEAR AND FAILURE. CALL FACTORY FOR ASSISTANCE