Have you ever wondered how machines that produce adhesives like Super Glue or Caulking don’t get stuck because of machine parts getting glued together? The following answers from the internet should provide you with a good explanation.
When the glue is running in the pipes it’s usually not exposed to air and it spends very little time in the tube so it can’t clog up. These factories might be running the filling machines 24/7 or when the machine is turned off, they run a solvent through the pipes to clean the left-over glue.
I’ve actually worked with manufacturing superglue as an operator of the machine. The industrial machine that makes it is pretty big with a lot of tubes. One morning when we came to work the machine malfunctioned due to it BEING SUPERGLUED TO ITSELF!
The glue in the tubing was usually heated to very high temperatures during downtime to avoid this from happening; this would lessen its adhesive properties. My coworker had forgotten to turn the heat on while ending his shift.
The machine was down for several weeks and they had to bring in a special team from the other side of Europe using some very nasty chemicals in order to unclog it. I found it ironic how million dollars’ worth of machinery designed to make superglue managed to… Superglue itself. This was the running gag for a while. The management did not find it remotely funny.
I work as an operator at a phenolic resin facility, where several of our mineral-resins just love to caulk & clog the pipes.
I cant speak for other processes & products, but our method to avoid entirely massive headaches is to do as following:
a) Keep the reactor-interior in a sub 0.3x atmospheric pressure environment. – This makes sure that oxidization that can set off caulking won’t occur.
b) We regulate the temperature carefully. Too hot and the resin starts charring into what looks like very very brittle, discolored glass. Too cold and it solidifies/coagulates (depends on type of product). Between 50-200°c is the general safe-zone.
After almost every batch we alternate between running boiling water, methanol, sodium hydroxide, sulphuric acid and even 16 bar of air (16x atmospheric pressure) through the reactor & all affected piping. This usually helps.