I think it’s safe to say that not many people know about the process of plastic extrusion. Thanks to intelligent and inventive workers in the field, it has become a relatively easy thing to become good at. There is fine machinery working together in order to cultivate your roll of tape, or the frame of your window. Without plastic extrusion, many things that we take for granted could not be made nearly as efficiently or effectively. Studying plastic extrusion has been a real treat! I’ve also been sharing what I’ve learned researching the subject with others around me. So little is known about something so common!
The core of the entire process is, of course, the material. The very first thing you’ll need is a material with the title of thermoplastic. The form of thermoplastic that you’ll need is that of small beads. As in many professions, there is much plastic extrusion jargon to learn. For example, this thermoplastic in the shape of small beads is most commonly referred to as “resin.”
The next step is getting the resin into what is really the beginning of the machinery process, the barrel. The best and most widely used way of going about this is using a hopper. A hopper is special in that it gravity feeds the thermoplastic resin needed to make plastic products. In order to make a more attractive plastic product, before placing the resin in the hopper, add colorants to jazz things up!
Once a specialist operates the hopper, successfully feeding the resin into the barrel, it meets what is called a “feedthroat.” All a feedthroat essentially is, is an opening at the rear bottom of the barrel. The resin travels through the feedthroat and it meets an industrial-sized screw. The screw pushes the resin at generally 120 rpm back into the barrel, which then begins to gradually heat itself.
Most of the commonly used extruders come equipped with cooling fans. What this accomplishes is to keep the temperature below a certain point (which a specialist establishes at the beginning of the process). The screw is also a truly essential bit of the process. There are five possible zones in your average thermoplastic screw, and depending on what plastic company you’re looking into, the specialists refer them to as different names!
The now completely molten plastic travels down the length of the screw. At this point in the process, the plastic has to travel through several compact screens. This is for the sole purpose of clearing up anything that may have contaminated it. Holding up the screens, is a device called a “breaker plate.” This is shaped much like a hockey puck, with holes drilled into it.
A truly grand finale for this plastic extrusion process (except of course, the cooling) is what happens next. The liquid plastic travels from the screens to the die. The die is such an important part of the machinery, mostly due to the fact that it gives the plastic it’s shape. Relying solely on the company and what the final product will turn out to be, the die shapes the plastic.
Now, even though this is an interesting act in this plastic extrusion play, this is the part where a specialist must be especially careful. If the stream of liquid plastic becomes too unsteady, you can find yourself out of luck! The plastic may come out with stresses and weaknesses on it. If they’re bad enough, a specialist may have to throw them out! After coming all this way!
Post time: 04-07-2017