Tiếng ViệtCoating Problems Are Not Just a Paint Problem
A Necessary Perspective for Stabilizing Industrial Coating Processes
Coating is not simply the process of adding color to a product surface.
Coating plays a role in improving appearance, protecting metal against rust, increasing product durability, and providing functions such as friction resistance, heat resistance, and electrical insulation.
In other words, coating is an important process that supports both the appearance and functionality of a product.
However, many problems occur in coating processes at manufacturing sites.
The color is not appropriate.
The coating film peels.
Dirt nibs or inclusions appear.
Drying is unstable.
The number of products requiring repainting increases.
The finished quality varies depending on the operator.
Rework becomes concentrated just before the delivery deadline.
When these problems occur, the first reaction is sometimes:
“Is the paint the problem?”
Of course, paint selection and paint quality are extremely important.
However, in reality, many coating problems cannot be explained by the paint itself.
Coating quality is determined by the interaction of paint, workpiece, surface pretreatment, coating method, equipment, drying conditions, working environment, operator skills, and the management system.
Therefore, to properly prevent coating problems, it is necessary to look at the entire coating process, rather than searching for a single cause.
A Coating Problem Is a “Result” That Appears at the Manufacturing Site
A coating defect ultimately appears on the product surface.
However, its cause may lie in an earlier process.
For example, when an adhesion defect occurs, the cause is not necessarily the paint.
There may still be oil or dirt on the workpiece surface.
The surface pretreatment conditions may not be appropriate.
The thinning ratio, film thickness, drying temperature, or drying time may also be inappropriate.
In addition, the operator’s procedure, the environment inside the spray booth, the actual temperature of the drying oven, or storage conditions may also influence the result.
In other words, a coating problem is an observable phenomenon on the surface, but many different factors may be hidden behind it.
If this point is misunderstood, the site will continue to rely on repainting or temporary corrective actions.
The product may be shipped in the short term, but if the root cause remains, the same problem will continue to occur.
Repainting Is Not Just Repair; It Is Also a Loss for the Business
Repainting is one of the measures commonly used at manufacturing sites.
However, repainting is not free.
Additional paint is required.
Working time increases.
The drying oven and other equipment have to be used again.
Inspection work also increases.
The schedule buffer before delivery becomes smaller.
The burden on workers also increases.
Furthermore, if repainting becomes routine, the site can easily develop the mindset that “we can just repair it again.”
When this happens, improvement activities aimed at reducing defects are delayed, and the coating process itself is not strengthened.
It is not easy to reduce repainting to zero.
However, it is important not to regard repainting as something that is “unavoidable,” but instead to see it as a sign that the process still has room for improvement.
A site with frequent repainting certainly has areas that can be improved.
The issue may be material selection.
It may be the coating conditions.
It may be equipment capability.
It may be the standard work.
Or the quality inspection criteria may not be clear.
Coating Quality Can Be Systematized More Easily by Looking at 4M
At CoatureVietnam, we place importance on the 4M perspective when examining coating processes.
Material
This includes paint, thinner, surface pretreatment chemicals, and the material of the workpiece.
Paint type, thinning conditions, drying conditions, and compatibility with the workpiece have a major impact on coating film quality.
Method
This includes coating conditions, work procedures, film thickness control, drying conditions, and inspection methods.
Even when the same paint is used, if the application method is unstable, the finished quality will also be unstable.
Machine
This includes spray guns, pumps, spray booths, drying ovens, conveying equipment, robots, and other equipment.
If equipment capability or equipment management is insufficient, not only quality but also productivity and the working environment can be affected.
Man
This includes the skills, judgement, training, and inspection habits of operators at the manufacturing site.
Even as coating processes become increasingly automated, human observation and judgement remain important.
These four factors should not be considered separately. They should be viewed as an interconnected chain.
This is the first step toward preventing coating problems.
Dealing with Coating Problems Starts with Observing the Manufacturing Site
Many coating problems cannot be evaluated based only on information written on paper.
The specifications may appear to have no problems.
The paint data may also appear to have no problems.
Equipment capability may appear sufficient.
Yet defects still occur at the manufacturing site.
Therefore, in the coating process, it is important to observe the actual site, actual workpieces, and actual conditions.
What workpieces are actually entering the line?
How are operators actually applying the coating?
Is film thickness stable?
Is the actual drying oven temperature appropriate?
Is the airflow inside the spray booth appropriate?
Is the surface condition after pretreatment stable?
At which process are defective products detected?
Only by checking these points one by one can we move closer to the actual cause.
Stabilizing the Coating Process Also Means Reducing the Burden on Workers
At manufacturing sites with frequent coating problems, workers are under significant pressure.
Repair work increases.
Overtime increases.
Urgent requests increase.
The pressure related to quality responsibility becomes greater.
Workers may be blamed even when the cause has not yet been identified.
This is not a good situation.
Reviewing the coating process scientifically and building a system that makes defects less likely to occur not only stabilizes quality but also helps reduce the burden on workers.
This is exactly what CoatureVietnam values in the concept of “Science and Care in Coating.”
“Science” does not simply mean looking at the paint or equipment.
It means looking at the entire process, systematizing the causes, and developing improvement measures that can be reproduced.
“Care” does not simply mean providing support in a kind manner.
It means building a process in which workers can consistently produce stable quality without excessive effort.
It means creating a work environment where the manufacturing site can operate with confidence.
It also means creating a condition in which customers can receive stable quality.
What Can CoatureVietnam Support?
CoatureVietnam does not only supply paint. We also support improvements across the entire coating process.
- Paint selection and thinner selection
- Checking surface pretreatment conditions
- Reviewing coating methods
- Checking film thickness and drying conditions
- Improving coating equipment and spray booths
- Improving the working environment
- Systematizing the causes of repainting and defects
- Developing SOPs and checklists that can be used at the manufacturing site
Coating problems often cannot be solved by a single department.
A comprehensive perspective is required, connecting materials, equipment, processes, operators, and quality requirements.
When facing a coating problem, it is not always necessary to start with a major equipment investment.
First, accurately identify what is happening at the manufacturing site.
Then determine together where improvement should begin.
That is the first step toward stable coating quality.
Summary
Coating problems are not just paint problems.
And repairing a defect after it occurs is not, by itself, true improvement.
It is important to look at the coating process from a comprehensive perspective.
The relationship between materials, methods, equipment, people, and management needs to be examined, while building a system that makes defects less likely to occur.
Strengthening the coating process helps stabilize quality, reduce costs, maintain delivery schedules, and reduce the burden on workers.
CoatureVietnam will work with customers involved in coating to promote improvement activities based on actual manufacturing-site conditions.
Science and Care in Coating.
That is the philosophy we value.