| This is a lab scale Braebender single screw extruder, part of a larger research apparatus, which had been left unused for at least twenty years. Extruder design doesn't tend to change very much, especially the simple ones, but the control system was an archaic rheostat box about the size of a small refrigerator. It was also badly corroded and irrepairable. I sent it to the electronics graveyard and got out an Omega catalog. With a little guidance from the Omega support engineer on the phone, I put together a control system and ordered all the components. A plant electrician and I put it together and it worked on the first try. I had earlier received a quote from Braebender on a new system for $14,000. The system shown here was smaller, worked better since it had solid state digital controllers, and cost about $800 total. The extruder was very handy for developing products in PVC formulations. I wrote a users manual for the machine and as far as I know, it is still in use today. |
