There are basically three different gear tooth systems for gear pumps.
Spur, helical and herringbone gearings are available to choose from for the pumps. Each of these types of tooth system has different properties that are decisive for the use of the type of gearing. The most commonly used system is spur gearing. Classically, involute gearing is used for gear pumps.
When pumping fluids, it is often important for the process that a constant product flow is present. Gear pumps are used in the plastics industry, for example, to produce profiles or foils. To ensure consistently high product quality, the product flow must not pulsate, as this would result in uneven layer thicknesses. The graph qualitatively illustrates the different pulsation behaviour of the various tooth systems. If particularly shear-sensitive media are conveyed or the process requires a low pulsation behaviour, a herringbone gearing is very suitable.
Compared to oscillating displacement pumps, the pulsation behaviour of gear pumps is significantly lower than that of piston diaphragm pumps, for example.
