“Since the part is immersed and needs to be brought back up through the contaminated bath, this method may not suffice when high levels of clean are required,” he notes.
“Depending on what you are removing from the parts, simple agitation may not provide enough action or impact to remove the contaminants. Adding spray under immersion may help.”
What factors need to be considered when selecting the best cleaning method for an application?
- Material composition of the part to be cleaned.
- Design of the part(s).
- Size of the part(s).
- Characteristics of soil that you want to remove.
- Level of cleanliness required.
How do you choose the right cleaning chemistry to use in the parts washer?
Spaziani says the most common cleaning chemistries are petroleum and organic-based solvents, and specialty solvents.
Petroleum and organic-based solvents clean by breaking down or dissolving the contaminants. These solvents typically cannot be used in high-pressure spray or ultrasonic applications.
Specialty solvents are available to address niche cleaning operations and applications outside of routine repair and maintenance (i.e., solvents built to strip specialty inks and paints). There are also specialty solvents built to meet certain industry specifications, like for military specs and the food industry.
There are two important things to consider when selecting a solvent to clean parts, says Spazian.
Watch the flashpoint
This is the lowest temperature at which a solvent gives off enough vapor to ignite when a flame or spark is present.
“Higher solvent flashpoints make safer products, but the higher you go on flashpoint, the slower the drying time and the lower the cleaning power.
“Find the right balance for your process, but typically, you can find a solvent with a flashpoint of between 141 and 160 degrees. This is not considered hazardous in most states and still cleans very well.”
Be aware of the volatile organic content (VOC) of the solvent
“Certain states or areas of the country have very specific regulations regarding the usage, storage, management and reporting of VOC-based solvents. There are low-VOC and no-VOC solvents available that you can try, but they are usually more expensive. If in a VOC-regulated area, aqueous chemistries are typically ideal.
“When selecting the right cleaning chemistry, always start with selecting the right cleaning method or process,” emphasizes Spaziani. “At times, this will limit your choices on what chemistry you can use, and the cleaning method is usually much more important to setting up an effective parts washing process.
Whenever the process allows, beyond the obvious performance criteria, he recommends considering chemistries that meet as many as the following criteria as possible:
- Non-hazardous and can be recycled or reused.
- Has been proven to maintain its efficiency over an extended period of time.
- Provides the best experience for workers in terms of odor, risk and performance.
“This usually starts by considering an aqueous-based cleaning solution that has a pH greater than 2 and less than 12, or by selecting a solvent with a flashpoint of greater than 140 degrees that does not contain any solvents listed on the EPA’s hazardous waste list.”
How can the spent parts washer waste be best managed?
It is very important to remember that there are two things to consider when determining whether or not parts washer waste will be hazardous and how to dispose of it properly, stresses Spaziani. They are the characteristics of the clean chemistry being used, and all the contaminants that are added to the bath during the cleaning process.
“It doesn’t take a lot of chlorinated solvents or metals before your bath becomes hazardous. Don’t leave this one to chance.”
He advises consulting a professional at an environmental company, such as Safety-Kleen, to discuss the cleaning process and even possibly to do analytical testing in order to limit liabilities and ensure that the wastes are being managed within the regulations.
Furthermore, Spaziani suggests choosing a waste hauler that will protect a company by offering assurance and indemnification backed by enough assets to keep the business safe.