What distinguishes a hydraulic system from a pneumatic system?

A hydraulic system is characterized by its use of liquids to transmit power, while a pneumatic system utilizes gases for the same purpose. The principle behind hydraulics relies on incompressible fluids, which can effectively transmit force through confined spaces, resulting in significant lifting or moving capabilities. This is particularly advantageous when high force generation is required in applications like heavy machinery and construction equipment.

In contrast, pneumatic systems work with gases, typically air, which are compressible. This allows pneumatic systems to be lighter and often simpler in design, but they typically lack the power density that hydraulic systems offer. The choice of using liquids in hydraulics allows for smoother and more controlled movements, as liquids can be effectively managed within the system, providing precise operation under load.

Therefore, the distinction hinges on the medium used for power transmission: hydraulics with liquids and pneumatics with gases. This fundamental difference between the two systems influences their design, application, and performance characteristics.