While still a relatively new player in the finishing field, the powder coating industry continues as the fastest growing industrial finishing technology in North America, with continued upward growth anticipated throughout the 1990's. A large number of products in the automotive, appliance, architectural lawn and garden hardware, and sporting goods markets currently benefit from a powder coated finish, and the list continues to grow as ongoing technological advancements extend its use to more and more industrial and consumer products.

Powder coating as an electrostatic finishing process was first developed in the mid-1950's, and took off in the 1980's, with North American powder coating production growing from 66 million pounds in 1986 to an expected 269 million pounds in 1996. This is a 308% increase in the last ten years, with some 5,000 powder coating systems in operation across North America today. Total annual sales of North American thermoset decorative powder coating materials could surpass $1 billion dollars by 2000.

Powder coating now represents more than 10 percent of the total industrial finishing market in North America, and 15 percent of the market where it directly competes with liquid finishes.

Continued growth of the powder coating market can be attributed to a number of factors relating to the "Five E's" — environmental compliance, energy savings, efficiency, excellence of finish, and economy.

While liquid finishes contain solvents which have pollutants known as volatile organic compounds (VOC's), powder coatings contains no solvents and release negligible amounts, if any, of VOC's into the atmosphere, hence eliminating the need for costly pollution control equipment. In addition, most powder coating overspray that does not adhere to the part can be retrieved and reused, virtually eliminating the waste found in liquid finishing systems.

With no VOC's, the air used to exhaust the powder spray booth can be recirculated directly into the plant, eliminating the cost of heating or cooling the make-up air. Energy is also saved with the curing ovens. Solvent-based coatings must heat and exhaust huge volumes of air to ensure that the solvent fumes do not reach a potentially explosive level, but the exhaust requirements in powder coating ovens are lower.

Greater efficiency is achieved because powder coating requires no drying or flash-off timet parts can be racked closer together on a conveyor, and more parts can be coated automatically. Powder coating does not run, drip, or sag, and this results in significantly lower reject rates.

Powder coating provides an attractive and durable finish, offering excellent resistance to corrosion, heat, impact, and abrasion. Powder coating materials are available for both compliance with air quality standards by installing a solvent incineration system as part of a low solids liquid application design.

Acme Fabrication Co. was surprised to learn that the capital costs for powder coating were very competitive to the other methods of finishing its products. This is especially true when it compared the capital costs of powder coating to low solids liquid spray including the solvent incineration system.

Operational Costs:

Capital costs alone are not a fair comparison of these different finishing technologies. So, Acme Fabrication Co. embarked on a comparison of operational costs. These operational costs consist of several parameters such as coating material, labor, clean-up and maintenance, energy, and rework. Each of these categories need to be examined separately to determine which finishing technology is least costly to operate.

Coating materials represent approximately two thirds of the total operating cost of any finishing system. These costs vary widely between the different finishing technologies that Acme Fabrication Co. is considering.

Acme Fabrication Co. employed the utilization efficiencies and film thickness that are representative, based upon standard industry practice, of the specific coating technologies used in this material comparison. Because of the recycling characteristics of powder coating, its applied cost is substantially less than any of the other finishes that Acme Fabrication Co. is considering. This is true even in light of a slightly higher film thickness often associated with powder coatings.

Because of the continuing rise in labor costs, operational labor along with clean-up; and maintenance costs are of keen concern to Acme Fabrication Co.

All of these benefits contribute to the bottom line, and hence the economic advantages for powder coating. The total cost savings of powder coating is best presented by comparing capital and operating costs of various finishing systems, as this case study will now illustrate.

Company Statistics:

Like most manufacturing companies, Acme Fabrication Co. is constantly looking to improve its profitability by streamlining its manufacturing processes and their associated costs. Coincidentally, its existing liquid finishing system has reached the end of its useful life and is in need of replacement. Faced with these facts, Acme Fabrication Co. is considering powder coating to replace its low solids finishing system. However, before the company can make a final decision in favor of powder coating, it must evaluate other current finishing technologies and their associated capital and operating costs.

Following, are the pertinent statistics:

Products: Various formed and welded sheet metal products fabricated in accordance to the customer's specification and design. These parts exhibit average finishing difficulty. The substrate is a combination of steel and aluminum metals. The maximum part size for this operation is 5 ft. high by 3 ft. wide by 10 ft. long.

Application: Both sides of the fabricated parts must be coated using automatic applicators. Because of the complexity of some parts, manual touch-up is required to aid in providing complete coverage of the part. All of the products produced in this facility will be coated at 1 to 2 mils film thickness using one of two proprietary Acme Fabrication Co. colors.

Production Rate: It is estimated that approximately 2.5 million square feet of surface area will be coated per year using this new finishing system. Production at this facility will be performed on a one shift basis, five days per week, for 250 working days per year. The conveyor line speed required to attain this production rate has been calculated to be 1 0 feet per minute.

Equipment Requirements:

After some consultation with finishing experts, Acme Fabrication Co. has determined that most of the finishing equipment is the same regardless of the type of system that is selected. For instance, the parts must be cleaned and pretreated, dried, cured, and conveyed without regard to the type of finish that is applied. Therefore the company is restricting its process comparison to the equipment required to apply low solids liquid, high solids liquid, waterborne liquid, and powder coating.

In each of these finishing systems there are applicators that are required to spray the coating, spray booths to isolate the coating operations from the plant environment, and specialized ancillary equipment necessary to meet code and safety requirements.

Unfortunately, Acme Fabrication Co. realized that there isn't any savings in operational labor costs since its system is designed to use automation as the main method of application. However, it did see a large reduction in maintenance labor and replacement part costs. This is largely due to the fact that powder coating systems have fewer moving parts and do not rely on mechanical pumps to feed the automatic applicators. Furthermore, the filters for powder coating systems, while being more expensive, require changing less frequently. Expensive sludge disposal is completely eliminated with powder coating since waste powder is classified non-hazardous and can be handled by services which normally deal with non-hazardous wastes. When all these factors are evaluated together, it becomes clear that Acme Fabrication Co. will expect to see a savings of more than 50% in maintenance and sludge disposal costs with a powder coating system.

Energy costs were also a concern for Acme Fabrication Co. So it compared these different finishing technologies on a basis of energy usage.

Since powder coatings require slightly higher cure temperatures, the "Total Load Loss" or BTUs required to heat its product is higher for powder coating. However, Acme Fabrication Co. noticed that there was no need for spray booth exhaust, flash tunnel exhaust, or solvent incineration for a powder coating operation. These three areas present Acme Fabrication Co. with significant energy savings over liquid finishes. When comparing total energy costs, powder coating is less costly to operate than low solids liquid and only slightly more expensive than high solids or waterborne finishing technologies.

It was time for Acme Fabrication Co. to total all the various operational costs for the different finishing technologies. It was here that powder coating was proven to be the finishing technology of the future with substantial operational cost savings when compared to liquid finishes.

This clearly shows the advantages of operating a powder coating system as compared to other spray finishing methods. One of the most interesting aspects of powder coating is its forgiveness during application. Because it is almost impossible to cause a run or sag when applying a powder coating material, the cost for reworking rejected parts is dramatically reduced. Therefore substantial savings in rework costs can be realized by Acme Fabrication Co. if it proceeds with the installation of a powder coating system.

The annual operational cost savings of operating a powder coating system was just the thing that Acme Fabrication Co. was looking for to reduce its cost of manufacturing. Ultimately, this makes its products more attractive to its customers in the cost competitive sheet metal fabrication market, while providing a finish that exhibits superior appearance and functional properties.

Payback:

As with any capital equipment project, Acme Fabrication Co. is concerned with the amount of time it will take to amortize the initial cost of installing a new finishing system. To this end, Acme Fabrication Co. compared the operational cost of each spray finishing technology to its existing low solids liquid spray operational cost to determine the annual operational cost savings. The savings, if any, were then divided into the capital cost for installing the new spray technology to determine the payback (in years) of converting to that technology.

Although all the spray finishing technologies offer some annual operational cost savings over low solids liquid spray, powder coating offers the most dramatic reduction in annual operating costs. Additionally a powder coating system, in this example, is less expensive to install than all the other spray application technologies. These two facts together make powder coating the most viable choice for Acme Fabrication Co. to replace its current low solids finishing system. In fact, its capital costs of installing a new powder coating system will be paid back in operational savings within the first year of operation.

As a result of this research and comparison, Acme Fabrication Co. joined the 5,000 manufacturers who already enjoy the benefits of a powder coating operation, providing an attractive, durable finish to their products with minimal environmental impact, and a maximum positive impact on their bottom line!