What typically lubricates gear pumps?

Gear pumps are typically lubricated by the material being pumped. In these pumps, the fluid itself serves a dual purpose, providing both hydraulic energy to transfer substances and acting as a lubricant for the gears within the pump. This design is advantageous because it ensures that the fluid properties, such as viscosity and temperature, help maintain lubrication and minimize wear and tear on the gears. As the material flows through the pump, it coats the internal components, allowing for efficient operation and reducing the likelihood of overheating or damaging the gear surfaces.

Using the pumped material for lubrication is especially common in situations where the liquid being processed is viscous enough to adequately lubricate the moving parts, which helps maintain performance and prolongs the lifespan of the pump. In contrast, water, oil, or grease typically do not serve the same function in gear pumps, as they may not properly mix with the pumped material or could lead to inefficiencies in the pumping process.