PT Blog

Tooling: Back to Basics on Die Springs Part 1

I counted more than 30 different types of springs in a well-known supply catalog, each with multiple variations. This month I will focus strictly on one type: compression die springs for injection molds. When you put a load on this type of spring it compresses, or gets shorter. The spring then pushes back against the load, trying to get back to its original uncompressed length. It is such a simple mechanism, and yet is often the cause of significant mold damage and downtime, usually due to improper selection or use.

The most common use of springs in an injection mold is to retract the ejector plates. We need to discuss this particular application because there are two contradictory beliefs. Theoretically, if the mold-closing sequence is adjusted correctly, there is no need to use springs, because the return pins will drive the ejector plates back to their proper position—flush against the stop buttons. If there is a concern about the noise, or potential damage to the return pins, Bellville washers can be installed under their heads to absorb the impact (see my November 2018 column). Alternatively and preferably, the ejector plates should be connected to the molding machine’s knockout system, which then controls the fore and aft position of the plates—also negating the need for springs.

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Metal vs. Polymer 3D-Printed Mold Tooling: Which is “Better?”

The use of 3D-printed injection mold tooling has been discussed, debated and tested extensively over the past 20 years. Implementation of the technology has steadily gained traction. While the technology is still far from “commonplace,” true innovators have now fully embraced it across many industries.

Even during the current global pandemic, interest is strong, and suppliers like Fortify are seeing a rash of new inquiries.

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PLASTICS Awards Danimer Scientific and WinCup as the 2020 Innovation in Bioplastics Winners

Earlier this month, we reported on how bioplastics are getting increased attention, even during difficult economic times, as was recently indicated  by the recent grant announcements by the U.S. Department of Energy (DOE). The DOE selected eight biomanufacturing companies to receive a total of nearly $5.7 million. Of the eight, Danimer Scientific was the sole recipient focused on creating biodegradable plastics. The grant will be used to expand commercialization of the company’s Nodax PHA (polyhydroxyalkanoate).

Now, Danimer Scientific and a leading U.S. manufacturer of disposable foodservice to-go ware, WinCup, Stone Mountain, Ga., have been jointly named as the 2020 innovation in bioplastics award winner by the Bioplastics Div. of PLASTICS (The Plastics Industry Association). The partners developed the first commercially sold straws made from PHA—a material verified as a reliable biodegradable alternative to traditional petrochemical plastic.

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Low-Pressure Injection Process Facilitates ‘Green Molding’

Since the technology became broadly available in 2017, a growing number of injection molders have been learning how the iMFLUX low-pressure process can reduce both cycle times and reject rates, especially in tricky molding jobs. As the plastics industry embraces sustainability and the circular economy, iMFLUX technology offers an efficient tool to process recycled and biobased materials, use less energy, cut waste, and reduce part weight. This article will explain how this low-constant-pressure filling approach, and iMFLUX’s unique adaptive process innovations, can transform your operation and provide a smooth journey to a “circular” future. (Scroll down for basic facts about the process and FAQs.)

Meeting the needs of a circular economy is no easy challenge, and most solutions come with significant tradeoffs for cost, quality, and operational complexity. Additionally, most solutions work only part of the time and address only a portion of the challenges. A solution is needed that delivers the necessary benefits and works with virtually any material, mold or molding machine—new or existing; hydraulic, electric or hybrid. This is where low-constant-pressure processing really shines.

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Dow Launches New Project to Reduce Plastic Waste in Nigeria

Dow’s Project ReflexNG is an initiative that aims to collect and recycle plastic waste in Lagos, Nigeria. This pilot project is aligned to Dow’s global STOP THE WASTE sustainability target, which will enable the collection, reuse or recycling of one million metric tons of plastic globally by 2030.

The project in partnership with Omnik, RecylePoints and the Lagos Business School Sustainability Centre, will specifically recycle water sachets through a pilot program, designed to show that they can be collected and recycled to be utilized in new, quality packaging applications. The project aims to divert 600 metric tons of sachet water pouches (approximately 300 million sachets), which otherwise would have ended up in the environment or landfill, into recycling applications while promoting education to engrain sustainability into a select group of small and medium waste entrepreneurs. The pilot is set up to enable a viable business case for the use of recyclate (resins made from recycled plastics) in non-food primary packaging applications.

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