Nova-Tech LMI Series G - SG Metering Pump - Manual (Page 18)

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If the pump is idle for long periods, temperature
changes in the process liquid may produce air in
the system. To discharge the air, install a valve in
the discharge line which will allow the process liq-
uid to be pumped to exhaust when starting the
pump.
Capacity Calibration
After the first 12 hours of operation, the pump may
be tested and calibrated to find the exact pump
capacity under specific operating conditions.
Usually, calibrating the pump at only 100, 50, and
10 percent capacity settings is enough to indicate
pump performance throughout the adjustment
range.
The pump can be calibrated by measuring the
decrease in liquid level pumped from a calibrated
vessel. This method is recommended for hazard-
ous liquids because it eliminates operator contact
with the liquid. Milton Roy test-tube Calibration Col-
umns are available for convenient and accurate
calibration of any pump.
THE FOLLOWING METHOD IS NOT
GENERALLY RECOMMENDED AS IT
MAY EXPOSE OPERATING PERSON-
NEL TO HAZARDOUS LIQUIDS. FUTH-
ERMORE, THE PUMP MAY OVER PUMP
DRAMATICALLY AND THE POSITION
OF THE CAPACITY ADJUSTMENT
KNOB MAY HAVE LITTLE EFEECT ON
MEASURING FLOW RATE.
The pump can also be calibrated by collecting and
measuring pumped liquid at the pump discharge
port. It may be necessary to create discharge head
at the liquid takeoff point so that the pump will
operate properly. (See Section 2 for recommended
ways to do this.)