At the BWM Group’s engine plant in Steyr (Austria), in a reference project accompanied by the Technical University of Vienna, Ecoclean Monschau (formerly Dürr Ecoclean) has significantly raised the energy efficiency of a flexible EcoCFlex Classic robot cell that had been in service for several years. The system’s electric power and water consumption were each cut by around 30 percent.
These energy efficiency measures are now intended to be implemented on another 95 systems of the same type installed at various sites throughout Europe and Asia.
The first EcoCFlex unit for cleaning and deburring engine components went into service at the BMW Group in 2005. Eleven years later, when the company was celebrating the 100th anniversary of its foundation, BMW ordered the 100th cleaning machine of this type as part of a major order. Representing the third generation of Ecoclean’s flexible robotized cells, this anniversary specimen was launched in production at the Steyr engine plant in early May 2017 along with two other EcoCFlex 3L systems. These cleaning machines are adapted to BMW’s latest specifications for technical cleanliness, replacing the transfer systems previously employed on a production line for spark ignition engines.
The EcoCFlex 3 combines modern and proven cleaning processes—such as injection flood washing, spray cleaning or high pressure applications—with the flexibility of SCARA-Manipulator (Selective Compliance Articulated Robot Arm). The entire control of the machine and the manipulator is carried out via a CNC control. Footprint and energy consumption were again significantly reduced compared to the earlier generations of that machine.
However, 30 first-generation units of this flexible cleaning machine are still in use at Steyr. Although their cleaning performance is still fine, in terms of energy efficiency—a parameter closely monitored by the BMW Group—the first-generation systems are no longer up to today’s standards. Water consumption in particular was too high. BMW Steyr therefore contacted the equipment manufacturer, inquiring if and how the machines could be energetically optimized.
Ecoclean has developed a potential analysis especially for this type of task. In their investigation, the service staff will focus on factors such as the water consumption, cleaning agent input, electricity demand, and the consumption of compressed air
Flow measurements revealed that large quantities of vapor were extracted from the cleaning cell, causing the machine’s elevated water consumption. Furthermore, the analysis identified a major electricity saving potential in operation of the feed pumps.
One measure taken to reduce the water consumption involved changes on the air control dampers. Moreover, the flow velocities inside the system were adapted via a modified fan control regime, resulting in substantially less vapor being discharged. In the case of the booster pump, a variable- frequency drive unit now provides demand-based control—and hence, energy savings.
With just these relatively minor improvement measures, the system’s overall electric power consumption was cut by around 30 percent. Savings of the same magnitude were achieved at the level of the water consumption, and are additionally reflected in a reduced need for cleaning chemicals.
The measures were initially carried out on a system installed in the Steyr/Austria-based engine plant. For an objective evaluation of results, the Technical University of Vienna accompanied the reference project with extensive pre- and post-optimization measurements.
Dürr sold its interest in the Dürr Ecoclean Group to Chinese engineering and machinery company Shenyang Blue Silver Group (SBS Group) in 2016. With annual sales of around €200 million, the Dürr Ecoclean Group was the global market leader in cleaning and surface processing systems for industrial parts.