Pump Notes

Pump Notes are short engineering notes from Vimpo Pump on viscous fluid pumps: pump selection, heating, safety and commissioning. Each note answers one question. The values come from Vimpo technical data sheets.

Why Bitumen Needs a Gear Pump

Hot bitumen is too thick for a centrifugal pump. See why positive displacement gear pumps move bitumen, PMB and oxidised bitumen, and how to start them safely. Read the note

Viscosity, Speed and Flow: Sizing a Gear Pump

Gear pump flow equals displacement times speed. See how viscosity sets the maximum speed and the motor power, with VD series examples from 2.5 to 100 m³/h. Read the note

ATEX Gear Pumps: II 1/2G Ex h IIB T4 Ga/Gb in Plain Words

Read the ATEX marking of Vimpo gear pumps field by field: zones 0 and 1, gas group IIB, T4, 130 °C liquid limit, Ex d or Ex e motor and mechanical seal. Read the note

Pump Heating: Thermal Oil Jacket or Electric Heating

A cold pump casing means a hard start with bitumen. Compare the thermal oil jacket (code T) and electric heating (code E) on Vimpo gear pumps, series by series. Read the note

The By-Pass Valve Is Not Optional

A gear pump keeps pushing against a closed line until a part fails. See how the integrated by-pass valve (code BP) protects the pump, and when to fit a line relief valve. Read the note

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