Everything You Need to Know About Parts Cleaning Solvents

Parts cleaning is a routine task for many industrial manufacturers who are required to meet strict cleaning requirements.

For years companies have been using petroleum based or other highly toxic and harmful solvents for their parts cleaning or vapor degreasing needs due to their low costs and effectiveness.

Precision parts ideal for cleaning in an ILSA vacuum degreasing machine

These solvents are effective, but continue to raise serious concerns for environmental, economic and health hazards. Companies are realizing the range of serious health issues and illnesses they are causing for workers along with the legal and financial risks associated for the business and making the switch to safer solutions for their needs.

Here is a guideline of the solvents to avoid, their issues and better alternatives.

Parts Cleaning Solvents to Avoid

Parts washers are extensively used to clean components of industrial machinery and equipment. Examples of parts washers include cold cleaning units, vapor degreasers, and conveyorized degreasers. Parts washers use cleaning solutions that can either be petroleum-based or aqueous.

Most degreaser or cleaning solutions in the US use harmful chemical solvent solutions to clean parts. Due to manufacturing and environmental industries becoming more aware of the risks, the government is stepping in. Minnesota recently passed a law banning such chemicals. As of June 2022, none of the following chemicals will be allowed for use in industrial cleaning equipment.

Recently Banned Solvents:

● Trichloroethylene (TCE)
● Perchloroethylene (Perc)
● Methylene Chloride
● Normal Propyl Bromide (nPB)
● Hydrofluoro solvents (HFC/HFE)

Petroleum Solvents Risks and Disadvantages

Petroleum solvents clean equipment by removing residue. Because they readily dissolve oil, grease, filth, and carbonized fuel, such chemical solutions are widely used for cleaning components. However, they comprise toxic volatile organic compounds (VOCs), mineral spirits, and other chlorinated solvents like trichloroethylene, perchloroethylene, methylene chloride, regular propyl bromide, and hydrofluoric solvents. These solvents are effective, but continue to raise serious concerns for environmental, economic and health hazards. A few of the most critical issues that come associated with their usage include:

● Petroleum solvents are also highly flammable, a significant safety concern in many industries.
● Petroleum solvents can contaminate with used oil, resulting in costly disposal.
● These solvents don’t always effectively clean the first time; they leave an oily residue, requiring additional cleaning.
● The chemicals in petroleum solvents are toxic enough to increase the risk of cancer for the system operators. Employers can control the exposure, but petroleum solvents evaporate quickly, making the process difficult.
● Solvent cleaning units are the largest source of hazardous waste.

What Makes Chemical (Petroleum) Solvents Hazardous?

Knowing these solvents’ individual compositions and harmful effects is important for gaining deeper insight.

Trichloroethylene (TCE)

Exposure can affect the immune and reproductive systems, liver, kidneys, central nervous system, and fetal development during pregnancy. Long-term exposures to TCE can increase the risk of kidney cancer.


Exposure may irritate the eyes, skin, nose, throat, and respiratory system. It may also cause liver damage and is a potential occupational carcinogen.

Propyl bromide

Negative health effects range from temporary health ailments — such as upset stomach, difficulty breathing, and watery eyes — to chronic conditions such as nerve damage, neurological issues, and cancer that are difficult if not impossible to determine.

Hydrogen fluoride

Some long-term effects include chronic lung disease, skin damage, scarring, prolonged or permanent visual defects, blindness, or destruction of the eye. Other body parts at risk include the fingertips, stomach, and esophagus.

Methylene chloride

Methylene chloride can harm the eyes, skin, liver, and heart. High exposure can lead to drowsiness, dizziness, numb and tingling limbs, nausea, and cancer. In severe cases, it can cause loss of consciousness and even death.

Aqueous Parts Solutions Alternatives

Many companies have now turned to water-based cleaners (aqueous parts solutions) as the mainstream alternative, which can be a great solution for certain applications, but not as effective for others.

While this has been the primary solution for the majority of degreasing equipment with no other available alternatives, Alliance is now able to cover the gap where water-based cleaning hasn’t touched.

Safe Effective Solvents for Parts Washing and Degreasing

Digital rendering of the ILSA machine showing the interior mechanismsAlliance has established itself as a premier supplier of eco-friendly cleaning methods throughout the last 25 years.

Thinking ahead, Alliance formed an exclusive distributor relationship with ILSA, a manufacturer of vapor degreasers based in Italy, which many companies in the US cannot yet access.

What makes ILSA degreaser equipment different is they use safe solvents for cleaning precision parts that are highly efficient, last longer, VOC compliant and have many other benefits. With their partnership, Alliance Manufacturing is now able to provide a great alternative to toxic solvents in addition to aqueous solvents and equipment.

Vacuum Vapor Degreasing Systems

Vacuum vapor degreasers are better than conventional open-top vapor degreasing equipment due to their precise cleaning and eco-friendliness.

Without water or scrubbing, the technique employs solvents to remove impurities from manufactured parts. Vacuum or pressure is used for cleaning and drying, and parts are finished by removing any remaining solvent. Typical processes include:

● Wash
● Secondary wash
● Rust inhibition (optional)
● Vacuum dry

These closed-system parts washers are perfect for applications requiring stringent hygiene requirements for cleaning and drying. Benefits include low VOCs, reduced solvent consumption, minimal waste, low odors, low corrosion, enhanced drying, compact footprint, operator safety, and highly effective cleaning for challenging parts.

Solvents Used by Alliance

Alliance is the top choice of all customers because we use safe solvents such as modified alcohols and aliphatic hydrocarbons to clean precision parts. Since modified alcohol is naturally inflammable and the air-free vacuum washing chamber prevents sparks from igniting, there is no fire risk. In addition, the wash cycle prevents bubbles from developing when parts are washed under a vacuum.

After the cleaning procedure, the drying cycle completely dries the parts in a shorter time, removing the need for hot air drying and additional drying operations. Moreover, we have the only contained system that can run Honeywell Solstice, a NASA-approved solvent. Solstice is an employee-safe cleaner that is highly effective, contains no volatile organic compounds, and has a high sustainability rating with a Global Warming Potential of less than 1.

Industry Applications:

Using their safe efficient solvents, ISLA’s vacuum degreasing systems have been effective in several industries including aerospace, automotive, and medical industries. Some of these applications include:

● Precision machining
● Turning and screw machining
● Hydraulic components
● Micromechanical components

This system can also easily remove coolants, chips, and other manufacturing dirt. Metal and various plastic components can also be cleaned and dried using vacuum degreasing.

Basket entering the wash chamber of a vacuum degreasing machine

If you are in need of spare parts, please visit our Parts & Service page.