Lessons Learned: Automated Robotic Painting & Dispensing
By now, it’s safe to assume that everyone is aware of the benefits of implementing robots to automate their painting and liquid dispensing applications.
Automation reduces costs and waste, improves quality and safety, and has countless other benefits. (If you haven’t heard much about it, Google has some very helpful and informative articles explaining and supporting the move toward robotic automation.)
At Saint Clair Systems, we strongly recommend automation. We hope this blog will give you a few useful things to consider as you decide whether or not to implement an automated fluid dispensing application in your operation.
What We’ve Seen
We have been fortunate to have a front row seat to several automated dispensing implementations, and we view the process from a unique perspective as experts in material viscosity and temperature control at the point of application.
In our industry, it’s typical to only see applications where a) the end user has already determined that temperature and viscosity variation needs to be considered up front, or b) they are having problems getting consistent results after an implementation.
Let’s talk about the group that runs into unanticipated problems after implementation.
Blaming the Material Supplier
When results are still unacceptable, we see the end users resort to adding an additional - but completely avoidable - process. What used to be referred to as rework at the time of implementation has now become a permanent part of the dispensing process.
Adding Extra Material
We have seen small groups of people, outside of the booth, with material and paint brushes looking for exposed substrate and dabbing on extra material. They called that a touch-up.
Second Coats
We have seen additions to a paint booth where a person sprayed another layer of coating over the robotically dispensed layer. Instead of calling it a second coat, they also called it a touch-up.
Buffing & Finessing
We have also seen coating lines where people buffed and added additional coating. They called it the finesse department. (In other words - a touch-up.)
At some point, rework became an inevitable part of their process.
Controlling Temperature
Through a series of trial and error, many companies finally conclude that the issue causing the variation in their dispensing process is temperature directly affecting viscosity. A variety of solutions tend to come from this conclusion:
Temperature-Controlled Rooms
Often, we will see companies build a temperature-controlled room around bulk storage or the mix room. This is an improvement to controlling the dispensing process, to be sure, but the important fact remains that the material path is still subject to a variety of factors that will ultimately impact temperature and viscosity.
Whether it’s process heat, changes to plant temperature, or routing over an oven, it’s unlikely that any material will maintain its temperature all the way to the point of application. Temperature-controlling the spray booth is definitely important, but it is not enough to guarantee material temperature at the point of application.
Inline Paint Heaters
Inline paint heaters can also improve dispensing outcomes, but materials will always be subject to the same variations unless they are installed very close to the point of application.
Additionally, inline heaters do not provide any opportunity for cooling if the material becomes warm enough to affect the dispense. While inline paint heaters can be the right solution for a variety of applications, it is important to know their limitations.
We consider the most important material temperature & viscosity to be the point of application. As the graphic shows, the only way to know the material temperature at the point of application is to measure and control that temperature at the point of application.
Moving Toward a Solution
If you haven’t automated your dispensing process, you may want to consider discussing it with an experienced company. A successful implementation will help you cut costs, reduce waste, maximize quality, and improve safety.
In the 30+ years we have been doing this, we haven’t seen an implementation that didn’t ultimately work out. Naturally, some go more smoothly than others, but, in the end, they have all resulted in overall improvement.
If you are considering automating a liquid dispensing application (paints, coatings, sealants, adhesives, etc.), make sure you ask questions and do your research so you can understand the impact of temperature variation up front.