Insights Into Ultrasonic Cleaning

As is the case with any manufacturing process, choosing the right ultrasonic cleaning method can mean the difference between wasting time and making money.

0
209

If you’re looking for ultrasonic gear-cleaning equipment, you may begin your search by logging onto the Internet or poring over spec sheets in hopes of finding a solution that best suits your needs. Chances are you may quickly become mired in a blizzard of technical terms and specifications about transducers, frequencies, harmonics, and chemistry that leave you more confused than informed. Although the superior benefits of ultrasonic cleaning may perfectly suit your needs, how do you unravel the complexities and obscure language of the technology when all you really want is a “plug & play” solution?

In the vast majority of cases, the users who can benefit from ultrasonic cleaning systems should not need to possess an in-depth knowledge about the science behind the technology. Nor should they have to agonize over choices in product design, accessories, or the chemistry of cleaning solutions used with ultrasonic systems.
“Ultrasonic cleaning is a very productive technology, but I believe that sometimes the equipment manufacturers are overly enamored with the technical aspects of it, making decisions more complex than necessary,” says David Arata, whose experience with the field of ultrasonics goes back over 40 years. He warns that while choosing any process equipment is hardly a no-brainer, it should not be overlooked that in many instances—particularly with inexperienced users—it is critical that the equipment marketer assist that user in making the best equipment selection.

Plug & Play Solution
Arata has a U.S. patent as co-inventor of a unique ultrasonic cleaning generator circuit, and he has traveled and met with engineers from around the world to understand their requirements for precision cleaning. He is now a marketing and technology executive with Omegasonics where he supports the test lab, the facility where new or demanding applications for ultrasonic equipment are proven according to specifications that are established with prospective customers who are uncertain about their particular application. Figure 1

Rather than dazzling such customers with technological information they’ll probably never need again, Arata’s laboratory approach calls for thoroughly and accurately determining the customers needs and expectations, which he feels are vital to simplifying their selection processes and making their ultrasonic cleaning solution truly plug & play friendly.

“We have extensive experience in quite a few industrial sectors,” he says, “including aerospace, gear manufacturing, food and pharmaceuticals, military, and utilities. Yet in virtually every sector the customer may have unique or changing production processes that must be addressed for them to fully realize the productivity and quality benefits of ultrasonic cleaning.”

As examples of diverse working environments Arata cites U.S. Navy ships that use a range of portable ultrasonic cleaning units to maintain and service components of various vessel systems. Large and small energy producers clean hundreds of large and small parts such as components of hydro- and gas-powered turbines that depend on thorough and efficient cleaning to maximize uptime, and each year more gear manufacturers are learning the benefits of this technology as well. Figure 2

Traditionally, parts cleaning has been laborious and costly. “The last time we performed an outage on one of our gas turbines, we rented a commercial parts cleaning agitation-type machine,” says Kim Townsend, maintenance foreman for power provider Farmington Electric. “We would wash the parts for 12 to 14 hours, then take them out and have to hand clean them. I actually had four guys tied up for probably a week of eight-hour days, sitting around the table with little brushes scrubbing and scrubbing and scrubbing.”

The reason for the extra hand-cleaning was that the rental machine had not done the job. The turbine contains a thousand bolts and several hundred turbine blades, so it was a very time-consuming process. “Using the Omegasonics cleaning system, we were able to get all of the parts cleaned up in a matter of four days,” he says, “and I only devoted one person to it.”

“Ultrasonic cleaning is a fairly straightforward technology,” Arata adds, “but it is nevertheless vital that the cleaning system satisfy user needs, which should be clearly identified by the sales rep teaming along with the prospective user.”

Quick Considerations
When proving an application at Omegasonics, Arata’s associates ask prospective customers to send sample parts to the test lab so that the best ultrasonic cleaning system may be determined. “While one of our models is likely to fit the need, it is important to know how clean the parts should be,” Arata explains. “That consideration will impact the choice of equipment, the cleaning solution chemistry, and the method of rinsing and drying cleaned parts.”

Work time is a critical ingredient of the evaluation process. In some instances a part may require immersion in the ultrasonic cleaner for 10 or 15 minutes. This amount of time may impact the choice of a larger unit, or perhaps multiple smaller units that can be moved to multiple locations if necessary or advantageous.

He adds that various models of equipment, ranging from tabletop models to large industrial washers and restoration systems, feature built-in portability. “A tabletop model may be very appropriate for smaller applications or those when it’s advantageous to move the cleaner to the proximity where parts are being serviced,” he says. “I believe we have been somewhat unique in designing cleaning systems that facilitate today’s ‘cellular’ manufacturing configurations. Even our large models have wheels, so they may be moved easily if a process changes configuration or if users wish to share equipment between locations.” Figure 3

Arata explains that the selection of cleaning solution that is added to the ultrasonic bath water is another variable that is determined by at the test lab. “When we are proving a specific customer’s application, we make a cleaning solution recommendation. The solution can be supplied directly by us, or in many instances bought sourced from commercial vendors. Once the optimum chemistry is decided the optimum water temperature and ultrasound transducer frequency range is determined. Once these factors are determined, the use of our equipment is literally ‘set it and forget it’ and requires no other setup than to pull the cleaner out of the box and plug it in.”

He notes that whenever Omegasonics proves a customer application at the lab, the cleaning process and results are recorded on video. If the customer prefers, the video can be emailed to them for review or further discussion. “This is pretty much all the documentation they need to evaluate our recommended solution,” Arata says. “It also provides another demonstration of how the equipment is truly ‘plug & play.’ But more importantly, the customer doesn’t have to contend with the somewhat esoteric technology of ultrasonic cleaning. They simply push a button to enjoy its benefits. The technical savvy is completely transparent to the customer, because all the necessary hands-on expertise is provided by us. And that usually makes life a lot easier for them.”