Injection Molding Machine Maintenance – The Electrical System

The electrical system of an injection molding machine is an important system for the proper operation of today’s molding machines. This is particularly true for the newer all-electric machines that more and more molding plants are using. The electrical system requires regularly scheduled and standardized component examination and maintenance.

The operating and nerve center of any molding machine is the electrical system, the control cabinet and the control panel. Molding machines have many electric and sensitive electronic components. Generally these systems are self-contained and do not need any maintenance but it would be advantageous to check the electrical system for the following:

  • Loose or pinched wires
  • Components should have a tight connection to their seat
  • Proper ventilation and component cooling is required
  • Proper cleanliness around electric components is required
  • Maintain proper wiring labeling techniques
  • Clean any air ventilation systems
  • Develop a basic electrical machine diagram

Maintenance personnel need to be proficient and and sometimes need to be licensed to work on any electric and electronic equipment. Many electrical problems on molding machines are related to pinched or loose wires, lack of cleanliness around electronics, overheated components or just electronic component failure.

Knowing basic electric technology and electronics and being able to trace a problem to the root is often enough to maintain the injection molding machine.

It is recommended that a certified trainer from the molding machine manufacturer train your maintenance personnel on all aspects of proper machine preventive and corrective maintenance procedures.

A machine malfunction is not necessarily always caused by the equipment. Sometimes it is how a machine is set-up that can cause a malfunction. So it is important not only to train your maintenance personnel on how to maintain the machine, but also on the basic set-up procedures for your plant floor.

Below is a sample video from Paulson Training Program’s Injection Molding Machine Maintenance training program.

Injection Molding Technician Training

Different injection molding plants use different titles for what are essentially the same job functions. In one injection molding plant an “Operator” may have the duties that a “Molding Technician” has in another plant. When Paulson is evaluating the training needs of a prospective injection molding customer, we always need to keep that in mind. Our “training audit” is quite comprehensive and includes matching specific job titles to specific job responsibilities. That is why we conduct in-depth interviews with the key people at the plant to make sure we are all talking the same language.

So when you decide to implement an on-going training process with Paulson, you can be assured that you’ll be getting targeted training to specific job responsibilities, not just a job title. In fact, that’s an important point to remember for any employee traininig you do in on you injection molding production floor.

The video segment below is from our Practical Injection Molding program and is targeted towards injection molding technicians.

You can see many more videos like this one on our YouTube channel and you can also get detailed information on Paulson’s entire library of plastic training programs over at the Paulson Training website.

Sample of Scientific Molding Training

The below video is from Paulson Training Programs, Inc. interactive programs titled Practical Injection Molding – Expert Module. In this module, the student learns the latest advanced techniques for optimizing their molding process using Scientific Molding principles. This is just a short segment of a much more in-depth course. The 4 interactive lessons in the Injection Molding Expert series are challenging material. However, anyone that wishes to become a top tier molder can do so if they take the time and simply follow Paulson’s step-by-step learning model.

The Practical Injection Molding series consists of 12 comprehensive 1 to 1.5 hour lessons, each one building on the material taught in the previous lessons. The course also features Paulson’s SkillBuilder™ injection molding machine simulator. This realistic simulation tool gives students the opportunity to gets hands-on experience in making machine control adjustments and seeing their effects on finished plastic part properties.

Of course, nothing can replace actual machine time, but that is an expensive way to learn. Using SkillBuilder, students can literally run through 10 molding cycles in the time it would take to run 2 cycles on an actual machine. That speeds up learning considerably and gives your employees the confidence they need when it is time to get in front of the actual machine.

Scientific Molding in the Real World

You don’t very often pick up an injection molding publication, visit a website, go to a conference or just shoot the breeze during lunch at the injection molding plant with the phrase scientific injection molding coming up.

This is a term that was first popularized by John Bozzelli through his seminars and many articles. The components of scientific molding have been around for some time.It all really started, believe it or not, back in the 1960’s with research done by Don Paulson when he set up the most advanced plastics research lab in the country at what was then called General Motors Institute (this was where GM ensured that the growing company would always have an adequate supply of engineers (there is a VERY instructive lesson there for any growing plastic’s processing company today).

Don Paulson discovered that the plastic only reacted to 4 primary variables – heat, flow, pressure and cooling. Sounds obvious enough today, but back then it was very novel. So much so that only the most advanced injection molders took notice, General Motors, Kodak, Polaroid and the Tech Group being 4 of them.

This also became known as looking at the injection molding process from “the plastic’s point of view”. These core concepts are what is at the heart of “scientific molding”.

If you like to learn more about scientific molding you can google it at find quite a bit of information. Meantime, we found this short video made by Hansen Plastics showing their scientific molding process running out on their production floor. Sometimes it’s just nice to actually see something in action rather than read about it.

The Practical Application of Scientific Injection Molding

scientific injection molding simulatorThe era when the injection molder could only learn molding by trial and error on the production floor is largely over. Today, molding companies can combine scientific molding with molding experience to develop skilled, problem-solving employees in months instead of years. The scientific approach to molding requires molders to understand that the machine controls affect but do not control the molded part properties.  The molded part properties are controlled solely by the plastic pressure, temperature, flow rate and cooling rate conditions in the mold . To become a true molding expert today, the molder must know which of the four primary plastic variables is causing a molded part problem.  And if the goal is to reduce cycle time which adjustments can be made that won’t change part quality.  The first step in scientific molding is for the molder to learn how each of the four primary plastic conditions affects the specific properties of the molded parts (part shrinkage, warp, cracking, strength, etc. An effective training program teaches molded part structure, the effects of the 4 primary plastic variables on that plastic part and how to adjust the plastic conditions using the injection molding machine controls. This knowledge provides the technical and scientific basis the molder needs to understand the cause-and-effect relationships affecting plastic part quality and cycle time. The next step is to be able to apply what he has learned.  The most effective way is to use an injection molding simulator.  Much like an aircraft simulator for pilots, an injection molding simulator allows users to set machine controls, run cycles and see the results on the molded parts, including likely problems.  Simulation is an extremely cost effective and fast way to gain molding experience without actual machine cost or potential problems an inexperienced molder  might make setting up and running an actual molding  machine.

Below is Paulson Training Program’s YouTube Playlist for the Injection Molding Fundamentals course