In addition, they're often quieter and generate less heat than electric actuators. Fluid power actuators can also be used in hazardous environments where electric sparks must be avoided. By using accumulators to store energy, a hydraulic power unit needs to provide only slightly more than the average demand, increasing efficiencies for machines with varying load cycles. In contrast, electric motors draw considerable current to maintain torque, even while stopped. Most motors will overheat and fail under these conditions.
Hydraulic cylinders are very smooth and efficient for linear movement.
There are no poles that cause cogging, and there's no need for backlash compensation. Although hydraulic and pneumatic power share many common characteristics, there are some key differences. For example, because hydraulic fluid is much less compressible than gas, hydraulics are preferable to pneumatics when precise position control is required. Pneumatic systems are also typically less expensive to build. Designing a Fluid Power System Designing the power circuit, as well as selecting and physically placing system components, is critical to maximizing the system's performance.