Optimizing Compressed Air Consumptions

Costs relative to the energy needed to enable the compressed air devices in a plant to function represent a share between 20% and 40% of total costs. Safen, a company with which Stima is developing business with the Aireka brand, creates innovative solutions for energy saving in the filed of fluid and mechatronic engineering. Besides recovering as much as 80% of the energy used, smart monitoring in industrial processing is also enabled.

by Elena Magistretti

Aireka is Stima’s new brand, a “container” of innovative products for automation. The company is cooperating on various projects with two partners: Simian Project, a start-up founded in 2007 in the heart of the Packaging Valley near Bologna, capable of providing a complete range of products and solutions for refrigeration with compressed air, and Safen Fluid & Mechanical Engineering, a start-up founded in 2011 within the I3P incubator of the Turin Polytechnic to develop innovative energy saving solutions in the field of fluid and mechatronic engineering.
Safen’s mission, oriented towards energy saving, is visible in its industrial products which may be installed in all main pneumatic applications. In order to obtain a substantial and tangible saving in the consumption of compressed air, action must be taken not just regarding the efficiency of production and transport (compressor room and distribution network) but also regarding the way in which the air is used by the applications.

A patented technology which directly affects the consumption of the applications
The main applications which may be optimized with Safen technologies are pneumatic cylinders, blowers and vacuum production. The technology which allows to affect significantly the air consumption of these applications is Pneumotrasnformation (patented) whereby part of the energy which would normally be dispersed by the cylinder through the discharges, is used to generate new energy useful for the actuation of the cylinder itself. Besides, integrated electronics allows to gauge the flow in and out of the cylinder to improve its efficiency, diminishing the air consumption further, but maintaining performances. The vision of the future is seen in the collection and processing of the data gathered: they are collected by sensors preset within the system, sent via wireless connection to the computer and processed by software which allows to carry out a constant monitoring of the system by the operators, allowing them to take action to solve any malfunctioning without jeopardizing either the savings or the correct functioning of the application. Within this framework, the support provided by I3P to Safen turned out to be essential: thanks to the incubator’s network it was possible for CNL to become a participant in Safen’s corporate structure, with a capital contribution which enabled the industrial development of the philosophy of Pneumotrasformation designed by the start-up. This philosophy was included in CROV_DS, a fluid-mechatronic device for energy saving, smart metering and predictive maintenance meant for manufacturing industries which use compressed air as an energy vector. In this regard it should be considered that the costs relative to the energy needed to allow the compressed air devices to function within a plant represent a share between 20% and 40% of the general costs.

A plug & play device which reduces compressed air consumptions by 80%
The principle of pneumotransformation is the basis of the CROV_DS device: by exploiting the reuse of compressed air, still energetically dense, discharged by a pneumatic cylinder, and by decreasing the pressure by means which do not disperse the energy, CROV allows to use up much less compressed air. Particularly the pressure is reduced by controlling the expansion of an energetic quantum of compressed air, producing work when going from a higher to a lower pressure level.
Within CROV there are 4 power valves managed by electropilots, who in turn receive signals from an electronic board which can process the signals coming from 4 pressure transducers allowing the calculation and measurement of all the physical variables needed to control the strength and speed of the cylinder.
This is a plug & play solution which may be easily installed along the cylinder. Installation is simple and does not imply the redefinition of the phases of the production process in which it is installed. The pursuit of the maximum possible saving target is obtained by means of a sensorized on-board artificial intelligence.
The same electronics needed to actuate the Pneumotransformation also allows real-time monitoring of consumption, quantification of savings and, above all, to obtain a fundamental flow of information regarding the conditions of the valve and cylinder allowing to implement what is defined as predictive maintenance. Dedicated software installed in the maintenance office communicates with the devices and keeps all CROV installations monitored, diagnosing the performances of the subsequent cylinders and valves and also detecting the internal leaks which are normally not identified. In case of leakage, CROV compensated by reducing it to the minimum level needed to guarantee the functioning of the subsequent application or, if possible, it eliminates it completely. In short, CROV allows to save up to 80% of the energy needed to produce compressed air, besides the possibility of verifying if cylinders or valves leak, and therefore to enact maintenance predictively.

The other products that contribute to energy saving
Smart monitoring and predictive maintenance are among the main objectives of Industry 4.0. UGETs, which optimize blowers, are mechanical devices designed and produced to obtain, with the same outcome in terms of kinetic performances, a lower consumption of compressed air compared to traditional nozzles. Depending on the application, it is also possible to obtain an optimization in the nozzles’ feeding system by means of Pulse-Width-Modulation, with a reduction in consumption between 40% and 60%. These devices may be installed in pneumatic appliances used in cleaning, cooling, handling items and, more in general, where it is necessary to keep an environment under overpressure. Vacuum production using compressed air is one of the most energy-intensive pneumatic applications. GEV is an optimized system for the control of depression in the activation of pneumatic suction cups. It is installed upstream of the suction cups instead of the traditional Venturi nozzles (ejectors), with customized solutions involving the use of simple effect cylinders or turbo pumps. A sophisticated electronic control system allows the management of limit situations such as, for instance, the detachment phase which varies according to the type of material to be handled using the suction cups. In this case savings add up to over 90%. Besides, Safen’s know-how allows the improvement of the performances of a company’s core product, also providing a competitive advantage obtained by means of the revamping of industrial processes. In this respect, Microleak is an innovative tool to verify the tightness under pressure and quantify losses by means of the technology of the differential drop in pressure.