Increasing Productivity in the Injection Molding Process

Part of calculating the productivity in an injection molding operation is to figure out the maximum number of items you’d be able to produce if everything worked perfectly. Unfortunately, “everything working perfectly” is not something you often see in manufacturing. How can you get closer to that ideal number? One answer lies in a little sensor which can monitor environmental conditions vital to your operation. With it you can reduce your machine downtime and the amount of scrap you produce.

Condition monitoring sensors seem to be taking the automation world by storm. These sensors take various measurements including temperature, ambient pressure, relative humidity, and vibration. They report the data digitally, which makes it easy to track performance. What used to require several sensors now requires only one.

Monitor humidity in plastic granule drying process

Following the plastic injection molding process from beginning to end we can see the usefulness of this one sensor. Plastic granules need to be dried before they go into the machine. If the moisture level is too high, it can cause splay marks to show up on the final product, which then has to be scrapped. This can be costly and can extend lead times if it is not detected early on. The condition monitoring sensor can track ambient humidity so you can stop that problem in its tracks before it creates waste and increases overhead.

Monitor temperature in the injection molding process

One of the biggest variables to any injection molding process is temperature. Some common temperature-related issues in injection molding include blistering, burn marks, degradation of the polymer used, stringiness, and warping. These are caused by temperature variations that cause the resin to be too hot or too cold. Condition monitoring sensors can detect swings in temperature to prevent products having to be scrapped.

Monitor vibration to detect mechanical wear

It’s clear that condition monitoring sensors can helpfully measure environmental factors, but what about mechanical wear? Vibration sensors can monitor mechanical wear on bearings, linear drives, gearboxes and much more by plotting vibration data. It’s even more effective if they measure vibration on more than one axis so you can see the direction of vibration and not just the overall amount. This way you can be proactive and plan your maintenance in advance instead of being in a constant reactive state, trying to patch problems as they come up. Using vibration data gathered by a condition monitoring sensor, you can avoid the costly consequences of unscheduled downtime.

In conclusion there are many different applications that condition monitoring sensors can be used for in injection molding operations. By tracking a variety of different measurements including vibration, temperature, and humidity, you will be able to improve the efficiency and productivity of your entire operation by using this one compact sensor. It provides a low-cost solution so that you can reduce the scrap that is cutting into your profits. And reduce the amount of downtime that causes so many unnecessary headaches. Put these smart sensors to work for you.

Injection Molding: Ignore the Mold, Pay the Price

Are you using a contract molding company to make your parts? Or are you doing it in house, but with little true oversight and management reporting on your molds? As a manufacturer, you can spend as much on a mold as you might for an economy, luxury or even a high-performance car. The disappointing difference is that YOU get to drive the car, while your molder or mold shop gets to drive your mold. How do you know if your mold is being taken care of as a true tooling investment and not being used as though it were disposable, or like the car analogy, like the Dukes of Hazzard used the General Lee?

What steps can you take in regard to using and maintaining a mold in production that can help guarantee your company’s ROI? How can you ensure your mold is going to produce the needed parts and provide or exceed the longevity required?

It is important for any manufacturer to understand the need for the cleaning and repair required for proper tool maintenance. The condition of your injection mold affects the quality of the plastic components produced. To keep a mold in the best working order, maintenance is critical not only when issues arise, but also routinely over time.

In the case of injection molds specifically, there are certain checks and procedures that should be performed regularly. An example being that mold cavities and gating should be routinely inspected for wear or damage. This is as important as keeping the injection system inspected and lubricated, and ensuring all surfaces are cleaned and sprayed with a rust preventative.

Figure 1 An example of the mold usage process.

The unfortunate reality is that some molders wait until part quality problems arise or the tool becomes damaged to do maintenance. One of the biggest challenges with injection molders is being certain that your molds are being run according to the maintenance requirements. Running a mold too long and waiting until problems arise to perform routine maintenance or refurbish a mold can result in added expense, supply/stock issues, longer time to market and even loss of the mold. However, when molders have a clear indication of maintenance and production timing, and follow the maintenance procedures in place, production times and overall costs can decrease.

Figure 2 Balluff add-on Mold ID monitoring and traceability system.

Creating visibility and accuracy into this maintenance timing is something today’s automation technology can now address. With todays modern, industrial automation technology, visibility and traceability can be added to any mold machine, regardless of machine age, manufacturer and manufacturing environment.

With the modern networked IIoT (industrial internet of things)-based monitoring and traceability system solutions available today, the mold can be monitored on the machine in real-time and every shot is recorded and kept on the mold itself using, for example, an assortment of industrial RFID tag options mounted directly on the mold. Mold shot count information can be tracked and kept on the mold and can be reported to operations or management using IIoT-based software running at the molder or even remotely using the internet at your own facility, giving complete visibility and insight into the mold’s status.

Figure 3 Balluff IIoT-based Connected Mold ID reporting and monitoring software screens.

Traceability systems record not only the shot count but can provide warning and alarm shot count statuses locally using visual indicators, such as a stack light, as the mold nears its maintenance time. Even the mold’s identification information and dynamic maintenance date (adjusted continuously based on current shot count) are recorded on the RFID tag for absolute tracability and can be reported in near real-time to the IIoT-based software package.

Advanced automation technology can bring new and needed insights into your mold shop or your molder’s treatment of your molds. It adds a whole new level of reliability and visibility into the molding process. And you can use this technology to improve production up-time and maximize your mold investments.

For more information, visit https://www.balluff.com/en/de/industries-and-solutions/solutions-and-technologies/mold-id/connected-mold-id/