MechChem Africa July-August 2022

Sustainability and energy efficiency: key priorities for automation systems

MechChem Africa talks to Skye Prato, Industry Sector and Business Unit Manager at Festo about how to improve the energy efficiency of automation systems and the need for all manufacturers to put sustainability at the heart of their operations.

Festo develops and sells both pneumatic and electric automation technology. Left: a DSBC pneumatic actuator. Right a EPCS-BS electrical actuator with a built-in spindle, motor and controller.

S kye Prato has beenwith Festo South Africa for over 20 years in various technical and sales positions. “I am currently the Head of our Business Units for Process Automation (PA), Electric Automation (EA) and industry segments such as automotive, food and packaging and the process industries,” he tells MechChemAfrica. “Festo core products are pneumatic actuators such as cylinders, actuated by pneumatic valves using compressed air; and the rapidly advancing range of electro mechanical actuators driven by stepper or servo motors using a mechanical spindle, tooth belt or rack and pinion to convert the rotating motion into linear movement. “Our actuators are supported by a full range of automation control products: Programmable Logic Controllers (PLCs) with ful l Computer Numerical Control (CNC) functionality built-in, HMI touch screens for operators, SCADA systems, Artificial Intelligence (AI) and machining learning systems for the modern Industrial 4.0 factory,” he explains. Pneumatic actuators are simple to man age, very cost-effective and they come with significant advantages. “For example, when a cylinder gets to its full forward position,

it stops by itself. Also, once fully forward – assuming there are no air leaks – a cylinder can, in theory, hold a clamp secure under pressure indefinitely, without consuming any further energy. It only consumes energy while moving,” he notes. This makes pneumatics ideal where clamping, gripping and holding periods are long as compared to release and retract periods. However, it is generally less ex pensive to use electrical equivalents for very short cycle times and brief holding periods,” he adds. “Two really important factors are now driving the adoption of electrical actuators in automation systems. The first is cost, and the other is, of course, to save the planet. Current energy use is consuming resources on our planet that we can't replace. These two key factors are driving manufacturers all over the world to reduce costs while im proving sustainability and energy efficiency. Improving the energy efficiency of pneumatic systems The best time to consider energy efficiency, according to Prato, is when a production project or an application is new and by plan

ning for efficiency upfront rather than as an afterthought. To achieve this, manufactur ers and plant operators need to align with suppliers that can offer themost up-to-date products and expertise. Once installed, it is vital to maintain those systems, and this is particularly crucial when it comes to pneumatics. “Pneumatics is still generally the most ef ficient and simplest way to clamp, hold, push and lift objects in industry. However, it is only efficient if these systems are properly maintained. Imagine having an electrical panel with sparks jumping out of it or a hydraulic hose with oil leaking out. These faults would be dealt with immediately. “But when it comes to a pneumatic system leaking air, it is not perceived as dangerous and is often just ignored. This is a huge problem with respect to energy efficiency. Pneumatic systems need to be maintained.” Skye Prato explains. Describing some other Festo innovations to improve pneumatic system efficiency, he says that the first involves reducing energy consumption on the reverse stroke. “For most pushing, clamping, holding and lift ing applications in industry, the pneumatic actuator is only required to apply force in one direction. On the return stroke, there is very little load requirement, yet in 99.9% of applications, the same pressure is used in the forward and return directions,” he explains.

Festo has developed a valve terminal cal led a Mot ion Terminal VTEM that au tomat i cal ly reduces the pressure on the return stroke of a cylinder. “In a 6.0 bar clamping application, we can save 30% of the energy used by the sys tem by simply reducing the return pressure to, for example, 1.0 bar. The motion terminal is digital ly control led

The Festo Motion Terminal VTEM bridges between pneumatics and the digital world.

36 ¦ MechChem Africa • July-August 2022