Material viscosity has very little effect on the dispensing consistency of positive displacement
piston pumps. The only effect material viscosity has in piston pumps is on the length of time
needed for the piston’s up stroke. This is because lower viscosity materials tend to flow quicker
than higher viscosity materials, allowing the piston chamber to fill faster. The graph below shows
how resilient the piston positive displacement pump is to viscosity changes. It shows volumes of
material dispensed over a wide range of temperatures or viscosities, since viscosity is directly
proportional to temperat