Tips for Improving Painting Lines
How design engineering can save time and money while lessening pollution and improving your paint finish...
Improving the bottom line through efficiency in all aspects of manufacturing is nothing new. All you have to do is look at Henry Ford's model of efficiency—the assembly line and all the modifications that have been made to it over the years—to begin to understand the contributions of design engineering to the production process.
Understanding new technologies and the critical relationships between these technologies and the time, resources and processes it takes to make a product is the domain of the design engineer. Manufacturers who work with design engineers are assisted in determining the most important areas for improvement, so they can take the steps necessary to affect change. The design engineer's primary goals should be to come up with practical solutions to the everyday problems manufacturers face, so the finisher can take steps to effect change.
Saving Time and Money
Most production managers would agree that there are always ways to improve the manufacturing process. But when faced with an entire operation as well as entrenched processes and mindsets, it can be daunting to find and implement specific ways to save time and money. Not only that, sophisticated testing and analysis may be required to make accurate comparisons among the options for change.
To ensure top performance, design engineers can help by conducting audits of the finishing process and generating reports listing the existing line conditions and recommendations for improvements needed to enhance the operation. They can work onsite to examine the actual coating process from start to finish and develop experiments that measure efficiency and successful application parameters specific to your needs.
When looking for ways to improve a process, here are several areas to examine and how a design engineer might help:
Change coatings. Are you really using the best coating to meet all your production and quality goals? What could you gain by changing to a different coating? A change in coating material can result in significant process improvements, including helping to reduce waste and therefore the costs associated with hazardous waste disposal, which are becoming increasingly significant.
A careful study of the coatings currently in use and the actual costs associated with their application—including labor and energy costs—can help determine if it is really the best coating to use to achieve quality results at a cost that makes sense for a business.
Changing coatings can be as simple as changing from a high solids, solvent-thinned coating to a waterborne coating, or it can be as involved as changing from a liquid to a powder coating. In one case study, design engineers found that switching from a liquid coating to powder would have a dramatic impact on productivity since parts coated with powder come out of the oven ready to be packed and shipped. As a result, workers were able to do more work faster and in smaller amounts of space than they did previously.
Powder coatings also provided a no-VOC solution to the problem of regulatory compliance since they contain little or no solvents or water waste. Waste was also reduced since powder overspray was collected, reconstituted and used again. Of course, the switch from liquid to powder involves a major capital investment in new equipment. But return on investment in terms of increased productivity and decreased waste made the change worthwhile for this customer.
Again, not all improvements recommended by design engineers are this dramatic. Even subtle changes can create results that are impressive. For example, switching to a new coating with faster dry time can improve through-put, with far-ranging results. A new coating system may provide a one-coat solution, eliminating the need for a primer, or perhaps fewer passes with the spray gun may be required to achieve the desired coverage.
Change Equipment. Would you benefit from an investment in new equipment or in making minor adjustments to existing equipment? How would a new racking system impact your finishing process? Or how about a more efficient baking system?
Since design engineers are very familiar with all of the different types of equipment available, they can make specific recommendations for applicators that can reduce spray time, overspray and waste. These recommendations may be sweeping, as in the case of changing from a liquid to a powder coating line, or they may be simple tweaks in your finishing process, such as adjustments to spray pressure or new valves. Often, such adjustments can have a significant impact on the amount of coating material used and the amount of waste produced.
Start Recycling. Starting a recycling program can greatly reduce waste. Paint waste costs money—twice. First, when a customer pays for coating material; second when that same customer has to pay to dispose of leftover material. Recycling programs can run the gamut from simply reusing leftover paint to developing a sophisticated collection system to collect overspray, recycle it and reuse it.
Design engineers can set up paint and color mixing labs at a site and train staff to use calibrating equipment to reconstitute paint and computer color matching systems to achieve a desired color.
At one furniture manufacturing plant in California, design engineers developed a unique filtration system using lightweight steel baffles to collect paint overspray. Today, the baffles are custom-made at the finisher's facilities in various shapes such as an inverted pyramid or tornado-type configuration. To make the baffles easy to use in various applications, they are vertically mounted on moveable wall units that are placed directly in front of the air filtration and exhaust system in each spray booth. What are you doing in your facility to recycle paint waste?
Consider Bulk Buying and Storage. The opposite of just-in-time delivery systems that reduce onsite warehousing costs, bulk buying and storage programs allow savings in materials costs and save time ordering and waiting for shipping. Not appropriate for all finishers, bulk buying and storage systems do have their advantages, such as when a large amount of the same material is regularly used and where turnaround times are high priority, so a delivery delay can be a costly inconvenience.
Design engineers can help to implement these systems by working with you to design and install bulk storage systems that are appropriate for various coating types. As part of such a program, you may receive information on approximate system costs along with a list of potential vendors to work with when selecting equipment components.
Enhance Training. When was the last time your painters were trained on proper application techniques? Are they trained on the proper handling, use and cleaning of equipment? Are they using optimal equipment settings? Are they operating in a safe and efficient manner? How could an effective training program enhance productivity on your finishing line? Design engineers can develop effective training and retraining programs for new and existing employees, taking all of these factors into consideration.
When to Call
Calling in outside consultants shouldn't be the first thing to do whenever you want to improve production. After all, no one knows the inside workings of your finishing line better than you do. Consider calling in a design engineering consultant when you:
- •Have specific goals in mind, specific questions or when you need specialized expertise to solve specific problems, such
as a paint failure or quality issue you need to solve, or an environmental regulation you need to meet.
- Need a totally new perspective on how to improve overall productivity.
- Could benefit from studies and analyses that are outside your capabilities or from testing conducted at an off-site lab.
- Seek knowledge about regulations, new technologies or equipment that is outside your realm of expertise or that
would require a significant investment in research or education for you to acquire.
- Have experienced recent or dramatic changes in production output, costs or product design or when new budget parameters need to be accommodated.
- Are considering a complete overhaul of your finishing line.
A good design engineer will work within your parameters to recommend solutions. For example, if new equipment isn't an option, what else can be done to improve the process? Design engineers can work with equipment manufacturers and finishers in the design and engineering of logistics and process parameters for various liquid or powder systems, determining the most efficient way for conversion from liquid to powder, defining stain and paint requirements, designing dip, storage and electrodeposition tanks, and reducing or eliminating paint waste and waste disposal.
Finally, one of the best reasons to call in a design engineer is to maximize the use of your time. Micro-managing rarely leads to a successful outcome, especially in the finishing business. There's hardly an industry that doesn't need to look outside its own offices and production space to find expertise to help with improvements and innovations. By letting the experts do what they do best, you could find the solutions you are looking for and save time and money.
Coating problems and solutions associated with particle size reduction...
Considerations when deciding whether or not a robot is the right choice for your facility...
A review of available test methods, common applications and innovative instrumentation...