Cleaning

Cleanliness of Parts
The first step for reducing waste in pretreatment is assessing the cleanliness of parts. Determine the sources of contaminates to reduce or eliminate them. Consider to what degree surfaces become contaminated with substances such as oil from machining, dirt from the manufacturing environment and oil from people's skin.

Cleanliness of the Process
Next, determine the cleanliness standard needed to satisfy the pretreatment process. Once contaminant sources are identified and cleanliness standards are set, determine which contaminants can be eliminated. Then, if contaminants cannot be reduced enough through process changes, assess the cleaning methods used.

Aqueous Alternatives for Cleaning Measurement Instrumentation Rosemount Aerospace Inc. is a large manufacturer of air data instrumentation used on both commercial and military aircraft. This MnTAP intern project tested aqueous alternatives to the chlorinated solvent used for cleaning two key instrument components.

Aqueous Cleaning Equipment Manufacturers Aqueous cleaning equipment suppliers offer a wide range of cleaning equipment and related accessories.

Aqueous Parts Washers for Small Operations Because aqueous parts washers use waterbased chemistries, they can be less hazardous to operate than petroleum solvent parts washers. This fact sheet describes the options available and has a list of suppliers.

Get It Plated Right Fact Sheet Series
This fact sheet series focuses on causes and solution for the most difficult cleaning problems for metal product manufacturers and designers. Although the series was originally written for plating, most of the same cleaning principles applies to other coating operations as well.

Cleaning and Design for Plating Lists some of the more troublesome parts for metal finishers to electroplate.

Cleaning Processes, Capabilities and Limits A large utensil manufacturer set up a custom-cleaning step to help eliminate troublesome soils. Also shows the value of eliminating soils at their source, before cleaning is needed.

Dried-on Process Fluids and Fluid Combinations Films of dried-on process fluids interfere with the bonding of plating to part surfaces. This sheet shows how to avoid the problems associated with dried-on process fluids.

High-Temperature Processing Burns on Soils Oils, coolants and many organic liquids form a varnish or paint-like coating on part surfaces when heated or aged. This fact sheet discusses how to prevent such soils from occurring.

Holes, Seams, Threads Recesses & Tubing Assemblies How to recognize and eliminate unseen pools of contaminates trapped in recessed part areas.

Particulate Contamination on Part Surfaces Explains how oversights that cause particulate contamination of parts before plating can be a costly mistake.

Selecting Materials for Plated Parts The type of metals used to construct a part can affect how easily it is cleaned and the part's physical condition after a finishing process.

Solvents and Vapor Degreasing
Solvent emissions should be reduced for many reasons.

• Solvent use can be costly. Traditional solvents-like trichloroethylene, methylene chloride and perchloroethylene-are expensive to use due to regulations, while newer ones are expensive to purchase.
• A National Emissions Standard for Hazardous Air Pollutants (NESHAP) limits emissions from degreasers using traditional solvents.
• Toxic exposure to workers is another concern.
• Large uses of traditional solvents, over 10,000 pounds a year, require reporting under the Superfund Amendments and Reauthorization Act (SARA)/Toxic Release Inventory (TRI) regulations and pollution prevention planning under the Minnesota Toxic Pollution Prevention Act (TPPA).

Alternative Solvent Degreasers These degreasing and cleaning solvents are marketed as alternatives to halgonated solvents—especially chlorinated solvents. In some cases, these solvents require more time or stronger physical action for cleaning surfaces. All have lower rates of evaporation and drying than the chlorinated solvents they replace.

Centrifuge Equipment and Services Centrifuges can be used for liquid-solid separation and to separate two immiscible liquids of different densities or molecular weights. MnTAP maintains this list of centrifuge equipment suppliers and services solely as a service to Minnesota companies.

CleanerSolutions Database Massachusetts Toxics Use Reduction Institute's online database is a tool for solvent substitution in surface cleaning. It links performance evaluations to specific testing parameters and environmental assessments based on the testing performed at the lab.

Marathon Ashland Petroleum to Save $39,000 through Cleaning Changes The company eliminated almost all chlorinated aerosol spray use, purchased parts washers with fine filtration to replace four rental washers, and found alternatives to a terpene-based, large surface spray cleaner.

Metal Stamping Company Saves $26,000 by Eliminating Vapor Degreasing Dayton Rogers Manufacturing Company in Minneapolis used a strategic deburring process to replace trichlorethane vapor degreasing.

Metal Treaters A commercial heat treater decreased water use by 90 percent with a portable wastewater filter system, drag-out reduction techniques and an automatic filling systems.

Multiple Stage Cleaning Reduces New Solvent Purchases & Saves Money Let your dirty solvent do your dirty work. That's the principle behind multiple-stage cleaning. With multiple-stage cleaning, dirty solvent removes most of the soil, while the clean solvent of the additional stages thoroughly cleans the parts and brings them to specification.

Petroleum Solvents and Production Changes Replace Chlorinated Cleaning Solvents To eliminate 1,1,1-trichloroethane and CFC-113, Windings, Inc. converted two vapor degreasers to cold solvent dip tanks, constructed two stands for drying parts and changed operating procedures to eliminate the final stator cleaning step on 85 percent of the units it made. Note: Although production of both 1,1,1-trichloroethane and CFC-113 was banned in 1995, these process changes apply to other chlorinated solvents like trichloroethylene (TCE), methylene chloride and perchloroethylene (perc).

Reducing Solvent Emissions from Vapor Degreasers Reducing solvent emissions can benefit your company in many ways. This fact sheet outlines strategies for reducing emissions from drag-out, drafts, diffusion and sprays.

Selecting a Still for On-site Solvent Recycling Become better prepared to select the right still for your on-site solvent recycling.

Solvent Recycling Equipment Many solvents can be reprocessed and recycled for reuse. Distillation is the most common method, but filtration can also be used. MnTAP maintains this list of solvent recycling equipment suppliers solely as a service to Minnesota companies.