IMPORTANT: Should your application require pump operation with a neg- ative gauge pressure at the inlet, consult the factory or your local Tonkaflo pump distributor.
When the pump operates with a suction lift, the suction pipe should slope upward to the pump from the source of supply. Provision must be made for priming the pump. To maintain pump prime, a foot valve can be used with an opening at least as large as the inlet piping.
When pumping liquid from a tank, the suction line must be submerged enough so air is not drawn into the suction line from a vortex. Increasing the size of the inlet pipe to reduce the velocity will help to prevent the vortex from forming.
Hot liquids within the temperature range of the pump must have sufficient positive head to prevent vaporization at the impeller inlet. The Net Positive Suction Head (NPSH) required data are included on the pump performance curves provided with this instruction manual.
The pump must never be throttled on the suction side.
After installation, test the suction line with water with a range of 20 - 100 psig (1.4 - 6.9 bar) pressure to detect any leaks.
Figure 3.1
Inlet Piping
3.3.2Discharge Piping
The discharge piping should be sized to properly handle the maximum flow and pressure developed by the pump.
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