Differences between Hydraulic Power Unit and Hydraulic System

Though closely related, hydraulic power units and hydraulic systems differ in definition. A hydraulic power unit generally refers to the power supply section of a hydraulic system. It consists of hydraulic pumps, electric motors, oil tanks and necessary valves, and delivers working fluid at set pressure and flow rate. Serving as the power source of the hydraulic system, it connects with actuators such as hydraulic cylinders and hydraulic motors via pipelines to drive various mechanical movements.

In contrast, a hydraulic system is a broader concept. It includes not only the hydraulic power unit, but also actuators (hydraulic cylinders, hydraulic motors), control components (various hydraulic valves), auxiliary components (oil tanks, filters, etc.) and working fluid (hydraulic oil). It amplifies force by adjusting pressure to realize power transmission and motion control for machinery. Hydraulic systems fall into two categories: hydraulic transmission systems, which mainly transmit power and motion, and hydraulic control systems, which focus on ensuring the output meets specific performance requirements.

To sum up, the hydraulic power unit is the power source of a complete hydraulic system, which is an integrated mechanical control system composed of multiple subsystems and components. The hydraulic power unit is one of the core parts of the hydraulic system.