Monitoring Versus Controlling Viscosity
At Saint Clair Systems, we’re fortunate to be able to visit many different manufacturing plants and review a variety of different processes. Regardless of where we visit, one theme seems to emerge consistently; “We can’t find good people.”
Having supplied fluid temperature and viscosity control equipment for over 30 years, we are finding that more companies are looking to us as a potential solution to help reduce the burden of finding qualified people. What follows is a brief description of the two things we have been suggesting to managers of automated paint and other fluid dispensing processes.
Monitor Viscosity Automatically
More often than not, the plants we visit are monitoring viscosity manually. Most of us have seen the process. A person dips a flow or efflux cup, (i.e., Zahn cup, Ford Cup, ISO Cup, DIN cup), into the fluid being dispensed, starts a stopwatch, and proceeds to time how long it takes for the fluid stream to break as it exits a hole in the bottom of the cup. Anyone manually monitoring viscosity understands the benefits. These cups are relatively inexpensive, easy to use, easy to train, and are relatively accurate. Most of us are also familiar with some of the shortcomings. People get different readings, the length of time between measurements can be long, and “it’s hard to find good people.”
To combat the limitations of manually monitoring viscosity, more companies are choosing to automate viscosity monitoring. Automated viscosity monitoring is simple and relatively inexpensive. There are several manufacturers of quality in-line process viscometers. These viscometers are easily mounted directly into the process fluid and provide constant reporting and recording of fluid viscosity. The benefits of automated viscosity monitoring are immediate. Readings are highly accurate, consistent, and reported in real time. More importantly, they allow you to utilize the good people you have more effectively.
If you determine that you want to try automating your viscosity monitoring system, please ensure that you are selecting the right viscometer for your process. Just as there are several manufacturers of in-line viscometers, there are also several different ways they measure viscosity. Different viscometers may be recommended for different material properties and application processes. We have a guide that can be helpful, (Viscosity Control Buyer’s Guide), or you can contact us and we can help point you in the right direction.
The only other thing we recommend you consider is to make sure your viscometer is easily convertible from monitoring viscosity to controlling viscosity.
Monitoring viscosity leads to controlling viscosity. If the fluid viscosity falls outside of the preferred range, somebody must adjust it. Even with an automated monitoring system, somebody needs to ensure that it stays where it needs to be to meet quality requirements. In most of the applications we see, the person monitoring the viscosity also controls it. This is done by adding solvent, (or water), to thin the material or in some cases adding virgin material to increase the viscosity. Similar to monitoring manually, controlling manually is subject to individual judgment, gaps in time between measurements, and it requires an experienced trained person. Monitoring automatically and adjusting manually is an improvement but most of our customers decide to do more. That is why we suggest making sure your viscometer is easily convertible from monitoring viscosity to controlling viscosity.
Our experience has been that when customers automate their viscosity monitoring, it does not take very long for them to automate their viscosity control. For a typical system, converting from monitoring to control consists of adding a simple set of controls, a solvent (or water) tank, and a valve. The signal from the viscometer is sent to the controller. When the viscosity moves outside of the prescribed range, the valve opens intermittently until the viscosity is back within its accepted parameters. The conversion is quick, simple, and effective.
So, if you are like many of the companies we visit and you are finding it hard to attract and maintain good people, it might be worth looking into monitoring your viscosity with an automated viscometer. If you like the results, consider expanding it into a full viscosity control system. It is simple, inexpensive, and it may take some of the load off the good people you have and want to maintain.