Successful manufacturers make it a point to look at cleaning options from new perspectives. They picture how those options can improve production – whether or not they plan an immediate change in critical product cleaning. There are lots of ways to gain new perspectives, including actual travel to programs, webinars, and virtual travel. This past fall, we gained inspiration from the parts2clean trade show in Stuttgart. Continue to read as we share insights that provide food for thought.
The show is totally devoted to cleaning, geared largely toward the automotive industry; but the techniques can be applied to many applications. While there were no formal seminars or tutorials, there were presentations on the show floor. Fortunately for us less fluent in German, the presentations were “simulcast” in French and English. Yes, there was plenty of “swag” (and fabulous snacks). We were impressed by the overwhelming number of technical folks at the trade show booths. We were especially impressed with the number of fellow nerds interested in communicating with attendees.
Given the legendary safety and environmental regulations in Europe, one might expect to see primarily water-based cleaning processes. We anticipated facing row upon row of parts washers but did not observe many. There were demonstrations of aqueous cleaning, including process controls such as bath monitoring and water re-use as well as higher frequency ultrasonics.
What was surprising was the number of different cleaning techniques offered. Examples include cyclic nucleation, laser cleaning, cleaning with various phases of CO2, and newer solvent processes that pose lower risk to workers and the environment. Some technologies have been around for years but may not be part of your standard repertoire of possibilities.
Most manufacturers are familiar with ultrasonic or spray systems. More manufacturers ought to also get to know cyclic nucleation. In cyclic nucleation, agitation is produced in a contained system by cycling the chamber pressure so that the boiling temperature varies. The process involves liquid phase (high pressure) that cycles (alternates) with an agitating boiling phase (low pressure). The technique shows promise where the boundary layer limits the ability of the cleaning agent to access, dislodge, and remove contaminants. Examples include porous components and interior of tubing/cannula. What agitation method is best: ultrasonics, spray, or cyclic nucleation? It depends. In some applications, a combination may be the answer.
Several exhibitors in Stuttgart demonstrated laser cleaning. While laser cleaning has been around for decades, it is being more widely explored. It is being adopted as a replacement for dry media for cleaning tires and molds. Developments such as the ability to tune laser wavelengths allows for selective contaminant removal and minimal substrate damage. Because it is a line of sight technique, the approach is not suitable if the laser cannot access the part to be cleaned. Issues of personnel protection and debris collection are being addressed by enclosure, through engineering controls and through automation. While laser cleaning has been adopted primarily in automotive applications, it could be adapted for other purposes. For example, it could be used in food processing to remove residue from baking molds.
CO2 – which phase?
CO2 cleaning employs momentum from impact or agitation and can be used in all phases: solid, liquid and gas. CO2 cleaning with solid pellets and snow is seeing increased usage in certain areas of manufacturing. Solid CO2 pellets can be used for aggressive line-of-sight cleaning, such as depainting, using high impact. It has an advantage over dry media where the residue of the media itself is an issue. Finer “snow” is much less aggressive and is used for cleaning small levels of residue from sensitive surfaces. Liquid and supercritical CO2 was not in evidence at parts2clean; the technology has been available for decades but adoption has been limited.
Keep an open eye
There’s no “one-size-fits-all” cleaning approach. These cleaning processes are in use by manufacturers – right now. Some are relatively new; others, you may have considered in the past, but decided they were a bit too “out there.” However, since requirements and expectations for cleaning performance have increased, staying with the ‘same old- same old’ may not be sufficient today. Keep an eye out for newer perspectives, including exploring older but not as well-developed technologies and applications.
Still have questions about which cleaning processes to consider for your application? Give us a call or send us an email. We can help you to stay productive.
Coming next—solvent cleaning perspectives
In the next installment of our perspectives from the parts2clean trade show, we will explore the evolving world of solvent cleaning. Long term halogenated solvents, hydrocarbon blends and alcohols are frequently superior in cleaning performance to aqueous processes. When handled in a responsible manner, they can be competitive in cost as well.