What Is Back Pressure in Injection Molding? 

We understand your pain! The struggle is real! Hopefully he see this video! 😅

My boss would have a conniption if he saw us doing that 😂 I can hear him yelling in his Huckleberry Hound voice “whatn tha hell y’all doin?!?”

You're welcome!

I ran single and twin screw extruders for six years, never once saw fluid cooled screws; it makes sense but i wonder what size screws you worked with?

what do you suggest me to start in ? wich product ?

We're glad you enjoyed it! Thanks for watching!

Awesome!! We're so happy it was helpful to you! Thanks for watching!

Thanks for sharing and for watching!! 😁

We're so happy you enjoyed it! And that you got to visit our facility! We hope to see you again soon! 🙂

Good luck! Let us know how it goes!

That's a great idea!! We'll add it to our list. Thanks!! 😁

Thanks, Mustafa! We're glad you enjoyed it! Simulation is a very useful tool to save time and money. Yes we use and offer flow simulations as a service. A simulation can be done to an existing mold/part or it can be performed in the very early stages of part and mold design. Multiple iterations of part geometry, mold design, and processing parameters can be simulated before money is spent on mold construction. Warpage , cycle time, knit line formation, and strength can all be analyzed. So yes, a DOE can be performed during simulation. The money spent on simulation has huge advantages and can save thousands of dollars by finding potential issues before part designs are finalized and molds are constructed.

Yes, weigh fill only parts and record them. That weight should be the part technicians use without any holding for troubleshooting.

My best guess is that it is because the product might not fall of at first ejection :)

Thank you for the comment. I would like to address a few of you points for you to consider. 1. The industry used to think that the plastic had a dramatic increase in temperature when BP was increased. But with modern instrumentation , Thermocouples in the nozzle and in the cavity, we have learned that the increase is modest at best. If the plastic temp is directly measured with a pyrometer rather than the reading on the barrel thermocouples, you can usually see that the barrel reading does not always correspond to the actual plastic temperature. 2. I did state in the video that increasing the BP will improve color mixing, although this is not usually the best option to improve color mixing. 3. I hear the statement about the real world a lot, usually this means that the machinery is in poor condition. This can make us believe a lot of false truths because we are seeing the result of poorly maintained equipment. Another point to keep in mind is that equipment is evolving rapidly. The molding machines I use today are not always the same as the machines I used 20 years ago. We as plastic processors learn something new everyday. It is healthy to challenge and be challenged in what we believe to be true , this has to be done with data. This is a small knit community that seems to be shrinking. Lets try to lift each other up and encourage each other to be better. I would be happy to try and come to your plant and spend a day looking at some of these topics if you are interested. Thanks! -Jason

@@rjg thanks for the reply, I was doing some day drinking on a rainy day off and just trolling a little. Wouldn’t a simpler test just to say make 100 shots without bp and use an infrared thermometer while purging then run 100 shots with bp to see the difference in temp? Unfortunately you are correct, machines all have the devil in them in one way or another. This is where real world comes into play. No machine is perfect in a manufacturing facility, you can do these test on a perfectly tuned perfect machine but that’s not what we have. Maintenance does their best but money and downtime always an object in the way. So tell me how concentrate color will mix better with bp? You have to be heating the molecules up to mix better, like I said more rotations/friction equals more heat.

@@downbelowu1928 The increased BP creates more revolutions of the screw. The improved mixing has more to do with allowing the metering zone of the screw to do its job, mixing. Great idea to do 100 shots at one BP measure then repeat at a higher BP. Let us know your results.

Andrew, I think we agree on this. We teach a scientific, systematic methodology to find the optimal BP. My stories are there to provide context from my mistakes early in my career. Over my years of instructing, I have found that some people need a direct to the point piece of information and some of us like a story or analogy to drive the point home. Us molders are a tight knit community, we have to pass on what we are learning to the next generation. Thank you for the feed back. - Jason

​@rjg I'll be honest Jason, RJG are highly regarded in the UK as a training centre, that's why I watched the video. Are you related (same company)? My comment was almost to distinguish if you were a professional outfit and by your reply, you are. I appreciate you taking the time to reply and it seems we very likely are of the same thoughts. There's many ways to get your point across, I guess for me if you'd explain the optimisation through systematic study first then discussed past wrong doings I may have felt differently, but that's just my opinion, not necessarily the right one.

@@user-mk4nm8yl3u Yes, we are the same company! We have offices around the globe, including the UK. We appreciate you watching and providing feedback! We certainly take it all into consideration. We hope you have a great day!