Why the move from traditional fluid power to electric actuation?

Things like production throughput, high energy costs, machine adaptability and the awareness of improved health and safety are high on everyone’s agenda. When considering these factors, a move to electric actuation offers many advantages over traditional hydraulic and pneumatic systems.

Hydraulic systems have traditionally been used when very high forces are required and on vehicle. Whilst the hydraulic rams are relatively low cost, the need for the infrastructure is high, the systems tend to be dirty and messy, have high maintenance needs and due to the high pressures involved can be dangerous. They are only suited to fixed strokes and with typical efficiencies around 45-50%, the systems have high running costs. Oil leakage can be hazardous, especially in some environments such as food processing.

Pneumatic systems offer low cost equipment, high speed and reasonably high forces. However pneumatic systems are inherently inefficient, with some estimations being only 10-20% of the energy required at the compressors at the application resulting in very high running costs. This is down to losses in the system, poor distribution, leaks and poor system design. Pneumatics have high maintenance needs to keep them running properly and are also only suited to fixed stroke and speed applications as these parameters cannot be easily changed.

Whilst it is clear that sometimes these systems seem to be the better option as electrical actuation may seem more expensive, an understanding of the benefits of these systems and looking at the total cost of ownership will help to understand the advantages of moving to electric. It is no coincidence that our cars are making the move to electric!

Electric actuators work on the principle of an electric motor driving a lead or ball screw with nut or a belt drive to produce linear movement. These are available as traditional rod-based actuators (cylinder type) or rodless, linear guided actuators. These are coupled with different motor types, from low voltage DC motors on simple applications, to a stepper or servo motors when dynamic applications or accurate positioning is required (standard servo systems typically offer 0.01mm repeatability). They have a wide speed range, offer high forces and are very low maintenance. They offer much higher efficiencies, with an electric actuator system being typically 80%+ efficient.

There any many further benefits of moving to an electrical system.

• Energy efficient
• Quiet operation
• High speeds
• High loads
• Accurate positioning
• Speed control
• Force control
• Very low maintenance
• Safety

As the electronics used in these are developing all the time, an electric actuator system is easily integrated into your control system using industry standard controls and Fieldbus networks; allowing things like speed, position and force to be controlled and changed automatically as required. These components are also easily incorporated into functional machinery safety systems, which alongside negating oil or air leaks and the high pressures involved with fluid power, lends electric systems to be fundamentally safer.

Offering this better control for your applications will allow for more efficient production, higher accuracies and better flexibility in your machines. Coupled with lower maintenance and running costs leads to an overall lower lifetime cost. Why not make the switch to electrical actuation now?

Motion Systems from Heason technology.

Heason Technology offers expertise in complete precision motion control solutions, with a full range of mechanical actuators, motor technology and our design and manufacturing capability for customised solutions. Please contact us for more information and to help with selecting the right solution for your applications.