Difference Between Piston and Plunger Pumps
From an engineering standpoint, it’s easy to understand that the main difference between piston and plunger pumps is the placement of the seals or O-rings. Again, the plunger pump’s seal is stationary while the piston pump’s seal moves with the piston.
So why do people always say that the quality of the plunger pump is better because its seals are not easy to damage if compared with your piston pump?