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Cleaning - Do You Know Where Your Dollars Are?

By Ed Sunkin

Cleaning parts in the machine shop doesn't come cheaply. According to Automotive Rebuilder's Machine Shop Market Profile about 15.2% of engine machining and rebuilding production work involves disassembly and cleaning. According to rebuilders that we surveyed, disassembly and cleaning accounted for the highest percentage of total rebuilding production time in the shop. So there can be significant benefits to reducing cleaning costs in the shop.

It's been estimated by many in the rebuilding industry that, depending on the product line and the type of cleaning equipment and system in use, cleaning accounts for 30 cents or more of each dollar spent on shop overhead. Cleaning costs can come from many different areas. First, there's the initial cost of the cleaning equipment itself, be it a thermal system such as convection, rotisserie or direct flame ovens, wet cleaning which includes hot tanks and other units designed to clean with hot water or chemical solutions, jet spray and pressure washers and ultrasonic cleaners and abrasive cleaning, which includes shot and bead blasting and shot removal equipment.

For a list of manufacturers and suppliers of cleaning equipment, refer to Automotive Rebuilder's annual Automotive/Truck Purchasing Directory contained in the January 1998 issue.

Second, there's the costs for cleaners, solvents or media used. The cleaning method you use in your shop will dictate these costs. Aqueous cleaning comprises a wide range of methods that use water, detergents, acids and compounds to displace soil rather than dissolving it in organic solvent. Aqueous cleaning has been found to be a viable substitute for many parts cleaning operations currently using solvents. Its principle disadvantage is that the parts are wet after cleaning and carbon steel parts rust easily in this environment. The additional cost of a rust inhibitor should be considered with this type of cleaning.

Techniques for reducing waste costs from aqueous cleaning include switching to detergent-based cleaners. Many shops are switching from solvent or caustic-based cleaners to less hazardous detergent-based cleaners. Operators should check that the type of cleaner used consists of surfactants that are good detergents but are poor emulsifiers (stable oil emulsions limit reuse of the cleaner and hasten its disposal). Agitation of the bath during use keeps the solids in suspension. Following prolonged periods of inactivity, however, the oily solids separate via flotation or settle to form a bottom sludge. Solution strength is maintained and bath life prolonged by removing these solids frequently.

Other costs associated with cleaning include labor, utilities to operate cleaning equipment, and shop towels, hand cleaners and uniform laundry services for employees. You also should consider water, sewer discharge and disposal of waste as cleaning expenditures. As with all consumables, the price of water and sewer continues to rise in many areas. In most municipalities, the more water you purchase - and usually the more you send to the sewer - the higher the price. The rising cost of water is a strong incentive for shops to use less.

So now that you know your shop is surrounded by cleaning costs, how can you go about reducing them and stretch your cleaning dollars?

One simple way to reduce cleaning costs is to monitor solvent composition in your cleaning units. Often in the shop, the decision to replace dirty solvent is made arbitrarily. At times, much solvent is disposed of prematurely. Monitoring solvent used in equipment will help ensure that the cleaning agents are replaced only when the solution is truly dirty, thereby saving you money on solvents.

You should also maintain solution quality. In addition to the dirt, excessive consumption of alkaline cleaner also can be due to using air for agitation and hard water for make-up. In some applications, the decrease in cleaner effectiveness due to dirt and sludge can be equal to the carbon dioxide and hard water salts of the water used to clean parts. Consider changing to mechanical agitation by means of jet sprays and use of demineralized water in place of hard water for make-up.

Analytical checks of solution strengths, performed by the operator using simple titration techniques, should be made routinely. The correction of solution strength by making small and frequent additions is more cost-effective than making a few large additions.

Waste elimination
If your shop is a Small Quantity Generator (machine or rebuilding shop generating between 220 lbs. and 2,200 lbs. of hazardous waste a month), you'll need to obtain and use an EPA identification number. To obtain this number, shops should contact their state's hazardous waste management agency or the hazardous waste division of their regional EPA office and request EPA Form 8700-12- Notification Of Hazardous Waste Activity. A booklet containing a form with instructions and portions of EPA regulations to help you identify your shop's waste will be sent to you.

The use of solvent sinks for small parts washing either on an owned or leased basis is being accepted as general good practice. According to the EPA, more than 95% of automotive repair operations have some type of solvent sink. When considering cost reductions in the shop, consider contracting with a solvent service company. For a monthly fee, solvent service companies such as Safety-Kleen Corp., Safe-Way Chemical Co. and many others offering this service, will pick up dirty solvent, clean and maintain the solvent sink, and refill the sink with clean solvent. Depending on the arrangement, solvent sinks may be owned by the shop or leased from the solvent service company. The cost for contracting with a solvent company may be less than the combined cost of solvent purchase, tank maintenance and waste disposal.

Many rebuilders rent or lease parts-cleaning units and solvents from solvent service vendors. These units usually consist of a parts-cleaning sink or compartment mounted over a drum of solvent. The rental is usually part of a package deal whereby the service vendor maintains the unit, provides fresh solvent, removes dirty solvent (either for disposal or recycling), and provides appropriate paperwork. This method of solvent management is very common.

According to the EPA, rebuilders subscribing to this type of service may be able to reduce the amount of hazardous waste they generate by examining the condition of the solvent when it is exchanged. If the solvent can still effectively clean parts, then the amount of time between solvent exchanges could be increased. Customers could arrange for exchanges of solvent to be as infrequent as possible. Also, the number of parts cleaning units in use could be examined to see if the number can be reduced. These two management techniques could help reduce the amount of hazardous waste generated.

You may also consider installing on-site solvent recovery equipment. Purchase of an on-site solvent recovery system is often viewed as a viable waste minimization option for solvent wastes. These stills utilize a bag liner (for ease of cleaning) and microprocessor control.

Based on the results of California Department of Health Services assessments, the low volume of solvent normally used at most small to medium repair operations does not justify the added expense of on-site solvent recovery equipment and maintenance costs. For large operations that do generate significant volumes of solvent, labor costs to operate the equipment and additional costs for disposal of waste residues are generally not competitive with current solvent sink lease and maintenance service operations.

Using a lease service may help control your shop's cleaning expenses. Similar to solvent lease arrangements, some companies offer a leasing service for hot tanks and jet spray washers. Hot tank arrangements include monthly leasing of a hot tank and monthly general maintenance service with removal of a set number of gallons of solution and sludge and recharge of solution with caustic or alkaline detergent and make-up water. Jet spray washer arrangements include monthly leasing of a jet spray, and monthly general maintenance service with removal of 10 gallons of solution and sludge and recharge of solution with caustic or alkaline detergent and make-up water.

Some shops are turning to bake-off ovens as a popular approach to reduce some cost in the cleaning process. Bake-off ovens are designed to pyrolize the dirt and grease, leaving a dry residue that can be brushed off. In most cases, abrasive blasting of the parts is required to remove all of the residue. According to Lyle Haley, sales/marketing manager for Peterson Machine Tool, Inc., the advantage of a bake-off oven is that it produces a small volume of dry solid wastes compared to a large volume of liquid waste. "Disposal of the dried powder residue from heat cleaning ovens is even easier and more cost effective than removing sludge from the liquid filter systems, " Haley said.

But the disadvantages of bake-off ovens may include utility costs, a potential for increased air emissions and the cost for abrasive blasting equipment and media.

Removing wastes
Then there's the issue of wastes generated by your shop and costs to remove them. It is important to hire a reputable, financially stable and state-approved waste remover who will dispose of your shop wastes legally. According to the EPA, if your hazardous waste is dumped illegally, your shop could be held responsible. And clean ups of hazardous wastes don't come cheaply.

In some areas, wastewater can be discharged to a municipal wastewater treatment plant; you may be required to obtain a permit from the municipality. If wastewater is discharged to surface waters, (ponds, rivers, lakes, etc.) via pipe or storm sewer, a discharge permit must be obtained. Check with local and state authorities to determine requirements and the appropriate permitting authority. If a wastewater treatment plant is not available or will not accept your wastewater, or if you do not have a discharge permit, route your wastewater to a tank or container for proper collection and disposal by a licensed waste hauler.

If you are rearranging your shop or moving to a new location, there may be added costs to consider. Floor drains should be connected to an oil/water separator to treat wastewater prior to discharge to sewers, surface waters, or containment. It is preferable to equip the separator with an emergency shut-off to prevent spills from entering the sewer, or discharging directly to surface waters. It is important to inspect the separator periodically and arrange for waste removal by a licensed waste hauler when required.

Do not discharge toxic or hazardous wastes to drain fields, dry wells, cesspools, pits, separate storm drains, sewers, surface waters, or septic tanks. Otherwise you may be in violation of federal, state or local requirements and subject to monetary penalties.

For those shops that acquire spent oils during rebuilding or remanufacturing and are looking for a cost effective way to dispose of these hazardous lubricants, burning may be the answer.

Clean Burn, Inc., of Leola, PA, manufactures coil tube boilers which burn used crankcase, hydraulic and ATF oils to provide a reliable, inexpensive source of hot water that's used in parts washing and other closed-loop heating operations.

According to Clean Burn, burning used oils recovered from vehicles or equipment relieves shops of cradle-to-grave environmental liability for off-site hauling and disposal of used oil, while greatly reducing high energy costs to heat water.

Cleaning solution technology
In an effort to provide alternatives to caustic cleaners and meet guidelines of the Clean Air Act, many chemical cleaning manufacturers have changed or developed formulas that are designed not to hurt the environment, or a shop's pocketbook.

Real-Green, from Oakite Products, Inc., is a heavy-duty cleaning and degreasing solution that is based on a blend of terpenoids and terpene alcohol. Known as biomass technology, this approach uses materials such as vegetables, corn, rapeseed, soybean, kenaf and trees to create products that traditionally contained chlorinated or chlorofluorocarbon solvents. According to its developers, Real-Green's biggest benefit extends to shop's wallets. Cleaning personnel can use as little as one part Real-Green to up to 150 parts water for cleaning and degreasing automotive parts, as well as rebuilding equipment.

Another cleaning solution was used to help a leading brake rebuilder of antilock braking systems reduce parts washer downtime and waste water disposal costs by nearly 90% by switching its aqueous cleaner.

Last year, LucasVarity Kelsey-Hayes, changed its brand of aqueous parts cleaners to the environmentally-friendly ARMAKLEEN® M-Auto available from Church & Dwight at its rebuilding facility in Wixom, MI.

The ABS units - each consisting of a painted motor, aluminum main valve body with iridite coating, plastic-coated wire, and other components with different types of plated surfaces - were typically coated with oil, grease, various underhood contaminants, and road grime.

LucasVarity Kelsey-Hayes' Quality Control Supervisor Ron Hasselbach, said he had searched for several years for an alternative to the caustic-based cleaner used to clean the ABS units sent in for inspection and rebuilding. Hasselbach said although the caustic-based cleaner did get the ABS units clean, the equipment had to be shut down and thoroughly cleaned in addition to changing the wash bath out every week to maintain cleaning effectiveness.

Hasselbach and Manufacturing Associate Bob Hapney said they had tried several different cleaners, though none provided significant cleaning or cost advantages over what the company was already using.

Last year Hasselbach came across some information in a trade publication about a line of environmentally friendly, carbonate-based aqueous cleaners used successfully in automotive parts cleaning applications. The new product could be used in his existing equipment and was about the same price as the caustic-based product.

Hasselbach and Hapney compared the caustic cleaner with the new one from ARMAKLEEN by systematically charting the operating parameters and other relevant aspects relating to the use of the products to view any possible cost efficiencies. According to Hasselbach, a 20 to 30° F difference in operating temperature for the cleaner would certainly have some impact on energy costs in the long run, though assigning a dollar amount to this decrease in electricity consumption would be difficult and probably not very accurate under the circumstances. Instead, the two chose to identify cost savings related to downtime and waste disposal.

The reduction in parts washer downtime means two items that translate into greater productivity. First, cleaning of the ABS units can occur more efficiently without weekly interruption. Second, the person responsible for cleaning out the washer each week is free to perform other duties in the shop. Depending on cleaning volume and labor costs, the amount of money this represents would vary from shop to shop. According to ARMAKLEEN, the cleaner switch at LucasVarity Kelsey-Hayes provided about 188.5 hours saved annually and a 90% reduction in downtime.

LucasVarity Kelsey-Hayes also found waste disposal reductions. The company has a main waste tank with the capacity to hold three dumps from their parts washer. So with their bath life with their original cleaner lasting only one week, a waste disposal contractor was needed every three weeks to empty the main tank.

But the bath life of the new product was eight weeks instead of just one, so the waste disposal interval was extended to 24 weeks or about twice a year.

Another occurrence Hasselbach and Hapney noticed with the new product was the oil skimmer on the side of the washer worked more efficiently by removing larger amounts of oil over a shorter period of time. Water at the top of the small tank adjacent to the oil skimmer was very dirty and oily, and the container catching the oil collected by the skimmer needed to be emptied fairly often, something that didn't occur with the caustic-based product.

This oil-splitting property of the new cleaner provided favorable financial benefits to LucasVarity Kelsey-Hayes Since the oil splitter separated out the oil from the wash bath and it was more easily removed by the oil skimmer, soil and oils were not recirculated into the bath. This resulted in longer bath life.

When more soil and oils are removed by the skimmer, less waste will accumulate in the cleaning equipment itself. Hapney said when using the new product, only a very thin layer of sludge had to be removed from the bottom of the tank during the shutdown at eight weeks as opposed to the large amount of sludge removed each week when the caustic solution was used.

And since the inside of the parts washer itself was a lot cleaner, both downtime and electrical consumption was reduced. "Our heater elements are working a lot more efficiently now," Hapney said. "We used to have to wire brush them every week to remove sludge."

Hasselbach recommended rebuilders who want to make the right choice for a parts cleaner need to look at the big picture, adding the product comparison he made did not center on superior cleaning effectiveness. "Carefully compare all aspects of the products you're considering," he said. "Systematically identify cost efficiencies and calculate the benefits. And, make sure you understand why one product is providing the efficiencies and cost savings you want. It's the best way to get the product for your needs."

Finding the right application
Changing cleaning methods or cleaning equipment can be a costly step for a shop. Researching is important. Don't be afraid to ask the manufacturer questions and don't make a decision by looking into only one type of system or company. Ask for some kind of cleaning demonstration on your company's soiled parts. Many manufacturers will conduct these evaluations at a testing facility on equipment similar to the unit being considered. Another good way to research cleaning methods is to attend various trade shows presented by the Engine Rebuilders Association (AERA) and Automotive Parts Rebuilders Association (APRA). Many cleaning equipment and product manufacturers attend these shows to demonstrate their merchandise.

Talk to others rebuilding the same products as you, but realize there may be some differences. Steve Winters, president of A.R.E. Industries, Inc., Wichita, KS, said when dealing with customers, he sells only what the customer really needs. "A big mistake a lot of customers make is that they want a machine just like their buddy uses, even though their buddy's shop is much larger or does twice the volume of work," he said. "The problem is even though a customer may have seen a cleaning unit operate and they feel comfortable with it, they may not need that size of equipment to handle their cleaning requirements. When a customer over-buys, cost-efficiency is reduced. The customer ends up paying more for the equipment, the parts take longer to clean, and the cost is the same whether they clean one or 10 parts."

But what if the company outgrows the equipment they have? Winters said he offers trade-ins to allow the company to upgrade their cleaning equipment as dictated by their growth. Rebuilders should research whether the company they buy new equipment from now will allow trade-ins of that equipment for upgrading purposes at a later date.

Winters said another way to save money is to keep your cleaning equipment in proper working order. Rack systems should be maintained in good condition, free from cracks, rust and corrosion which can flake off and contaminate the bath. Metal tanks should be properly coated with protective finishes both inside and out. Spray nozzles should be inspected regularly to avoid clogging. "A lot of people think buying filtration units will solve all of their maintenance problems, but they don't," Winters said. "You still have to have a maintenance program. These accessories don't clean themselves. Without a maintenance program, shops don't realize how much they are loosing in downtime, labor costs and most importantly - equipment longevity."

David Zehren, product manager for Georg Fischer Disa Goff, Inc., Seminole, OK, agreed, saying proper maintenance will aid in cost savings. "By periodically cleaning machine and generator tanks, the buildup of heat-reducing gunk on the heating tube is reduced and therefore it offers a higher heat efficiency transfer," Zehren said. "When you have gunk buildup, the burner is less efficient and it requires longer heating cycles to achieve and maintain the proper operating temperature. This also causes faster and larger temperature drops in the tank with slower recovery times."

As long as there is rebuilding, there will be the need to clean, along with the costs that go with it. How your shop chooses to reduce these costs will depend on thorough research. Remember whatever you decide to change, the right decision is the one that not only improves part cleaning quality, but saves you money as well.