Polymer injection moulding & reciprocating screws: successful since ever, but what will happen in the future?

Figure 1: cross-sectional design of Willert's plasticizing unit.

Recently, PTonline posted an article about the invention birthday of the reciprocating screw and the injection moulding apparatus patented by William H. Willert (Clinton). This was what triggered me to have a look at the current plasticizing systems and related future concepts:


In Figure 1 the cross-sectional design of the plasticizing system of Willert’s patent can be seen. It is composed of three main elements, i.e. the reciprocating screw, the barrel and the material delivering part. If we compare the plasticizing unit of the figure to those implemented in our nowadays injection moulding machines, we won’t find much of a difference.

Before we think about implementing new plasticizing systems, a basic question arises: Do we already know (after 60 years) everything about the melting process during plasticizing, respectively the temperature of the melt in the antechamber?

There are analytical models such as the melting model of Tadmor [1], which describe how a solid bed of polymer pellets are melted in the plasticizing unit by the heat transferred from the hot barrel and the shear heat, also known as viscous dissipation, generated by the rotation of the reciprocating screw.  In injection moulding processes, the screw reciprocates until the necessary amount of polymer is melted.  In the best case scenario, a homogenous temperature distribution of the melt in the antechamber is attained. In this case, all the melt components, e.g. polymer, colors and additives are equally distributed throughout and we can say that “the screw has done a good job”.

However, how can we analyze the distribution profile of the melt temperature?

Formerly, the melt would be separately injected into a thermally isolated cup and a thermocouple would be inserted into it to record the temperature (offline measurement). This would simply show whether the temperature profile set on the barrel was reached.

Just very recently and yet at university level, an innovative inline measuring method has been proposed [2].  This utilizes an ultrasound sensor-based system which determines the axial profile of the melt temperature in the screw chamber and channels via reflection. Such inline measuring capabilities will allow us to further develop and improve the plasticizing process with the aim to decrease temperature gradients within the injection unit. The inline accessed data will be crucial to set up and validate more accurate CFD simulations of the plasticizing process. Therefore, simulating the plasticizing process utilizing different mixing elements in a reciprocating screw set up will lead to more assertive conclusions regarding the best design to enhance the melt homogeneity. Consequently, though the principle of the reciprocating screw will remain, new screw designs may finally arise in a near future to meet the requirements of processing ultra and high performance plastics, such as PI, PEEKs, PAEKs, etc.

Besides reciprocating screws, which other plasticizing systems can be found in injection moulding?

• Ultrasonic Injection Moulding

In the field of replication of micro parts (parts containing micro features whose weight is below 1g) the development of new plasticizing solutions starts to be noticed. Current micro injection moulding machines use two stage systems, which allow a separation of the plasticizing phase via extrusion and the injection phase via a stamper. For precise injection of few grams of melt for moulding micro parts, plasticizing by means of ultrasonic energy emerges as a new alternative [3]. Ultrasonic injection moulding machines utilize ultrasound energy to enable the transition from granule to melt in a homogenous manner throughout the plasticizing unit. Thus, the residence time of the melt is reduced to a minimum, which is advantageous when working with materials prone to degradation by the process temperature and/or shear. Overall, this is a totally new concept of injection moulding, which requires new strategies for process control as well. Let’s see how this technology develops, but it looks certainly promising in businesses, such as healthcare and watch manufacturing for instances.

• Inverse screw injection moulding

Finally, plasticizing small melt amounts can also be realized by a new concept based on an inverse screw system (see Figure 2 below) [4]. The main difference to current injection moulding reciprocating screws can be found in the internal structure of the inverse screw: the screw flights for conveying the polymer pellets into melt are part of the cylinder. Using this internal structure sufficient space for processing standard pellets in the feeding section can be accomplished. Furthermore, the diameter of the plunger is reduced. This plunger is placed coaxially within the cylinder. The main advantage of this design is to have the melting benefits of a reciprocating screw combined with the precision of a plunger during injection. This system was already tested for several commodities and engineering thermoplastics. Benefits include shorter residence times and precise repeatability, which makes this system also a promising development partner in the manufacture of high precision parts.



Figure 2: Schematic representation of the inverse screw unit [4].



The above mentioned systems are the pioneers who set foot on the ground of new injection moulding innovations and they will be niche players. In the field of microreplication more and faster movements can be seen in terms of completely new developments that totally disrupt well-known plasticizing systems. Let’s see what will be presented at the K show this year in Düsseldorf.
Greetings and until soon!

Herwig

Literature:

[1] Z. Tadmor: Fundamentals of plasticating extrusion. I. A theoretical model for melting; Polymer Engineering& Science, Vol. 6, 1966

[2] B. Praher et al.: Non-invasive Ultrasound Based Temperature Measurements at Reciprocating Screw Plastication Units: Methodology and Applications, PPS-30, 2014

[3] Ultrasion S.L.  (http://ultrasion.eu/)

[4] Ch. Hopmann et al.: New plasticizing process for increased precision and reduced residence times in injection moulding of micro parts, CIRP Journal of Manufacturing Science and Technology, 2015



Polypropylene Roller Coaster

In this blog post I present you an infographic about the polypropylene (PP) market. The reason for presenting this information is the growing surplus of PP material and its weak demand. These factors have led to a price drop that started in May 2015.

PP is, spoken for Europe, a multipurpose material for the automotive industry (ahead of PUR and PA). Furthermore, it is heavily used in electronics (ahead of PUR and PS) and is the second most important packaging material (right after PE and slightly ahead of PET). Finally, PP is also important in construction where it ranks behind PVC, PE, EPS and PUR in the fifth place.

I structured the infographic on the basis of 5 facts. These will give you a better feeling about the current situation and you can use this information for your further decision making in plastics industry:

• Fact 1: Margin C3 and PP
• Fact 2: The production
• Fact 3: The manufacturers
• Fact 4: The top-10 countries
• Fact 5: The capacities

Have a look for yourself!

Enjoy and till next time.

Greetings,

Herwig

Literature: kiweb.de; polyglobe.net

Edi-Pasteuring approach – is this a feasible way of research & development in the plastics industry?

This blog post will show a R&D concept which in my point of view allows you a better categorization of your research approaches. For making it easier for companies to bring structure into the R&D departments, science has investigated the patterns of innovation processes. The results can be graphically displayed in the so called Pasteur’s Quadrant (Figure 1).

The Pasteur's Quadrant is a way of combining the basic and applied research approaches in the shape of a quadrant. The quadrants can be separated by a horizontal (=consideration of use) and a vertical line (=focus on fundamental understanding). In my point of view, in the last decade, the right side of the quadrant started melting together resulting in this particular expression of Edi-Pasteuring (Figure 2).

Figure 1: Schematic presentation of the Stokes Pasteurs quadrant adapted from [1].

Let’s jump one step back and lose some words about two of the quadrants: What is a Pasteur-type of research approach?
Put in simple words: it is a use-inspired research approach. It has a scientific basis (understanding of the physics behind the product) and considers the boundary conditions (physical limits) of the practical application as a result of the scientifically findings and developments. This quadrant was named after Louis Pasteur, who got famous with his foundations in microbiology. His approach of reducing death by preventing diseases is a good example of this category.

And what is an Edison-type of research approach? Thomas A. Edison, the founder of General Electric and first industrial R&D scientist, is famous for his 2 quotes:

“Genius is one percent inspiration and ninety-nine percent perspiration."

And by this saying:

“I have not failed 10,000 times. I have not failed once. I have succeeded in proving that those 10,000 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”  

This quote explains already his way of research: you need to have a try & error approach in your research activities to succeed.

And what is Edi-Pasteuring?

It is the melting of those two quadrants for providing a way in the new economy of plastics industry to keep on the top.  Important is therefore to ask:

• Can this concept of Edi-Pasteuring work in plastics industry?
• Or is the melting of those two approaches already a consequence of a successful business?

In my point of view it is already used and represented by e.g. rapid prototyping, which always uses a proof of concept on a small scale with evaluation. This allows you to showcase your product. In this phase it is important to consider the physics behind which allows it to work in a proper way and estimate the boundaries. Once this is done, a scale-up to real application development is the next phase. Both phases will have some try & error elements. The proof of concept phase is more oriented in the Pasteurs approach, where else the application and scale up phase is will be dominated by Edison approach. It has much more try & error elements, because you want to improve your product. You want to try out different polymeric materials and different insert configurations when you use injection or extrusion moulds.

In the Figure 2 you can find a graphical representation of my interpretation of the research approaches for plastics industry. The Figure 3 shows the same adaption but presented in a more technical way. The melting of the two quadrants lead to a bell distribution with overlapping phases.  It reminds me also somehow of a bi-modal distribution of e.g. a HDPE.

Figure 2: My interpretation of the research approaches for plastics industry using the Pasteurs quadrant from [1].

Figure 3: Edi-pasteuring as a technical representation: proof of concept phase (blue line) and scale up phase (orange).

How does it fit into the new economy?

To be valid in the new economy, it needs to be aligned with the zero to one way of creating products (see Peter Thiel) together with 3 significant words: TEMPO, TEMPO, and TEMPO. The right timing of your idea to be placed in the market is crucial. When Edi-Pasteuring is supporting this idea and allows your product to become an exponential exploding product which can create a monopoly (short: 0 to 1), then it will stand definitely a chance.

If not, it will be only a concept working from the second row and getting a load of “me-too” type of products. The management of big data and its use will influence this kind of approaches as well.

Maybe those quadrants will be replaced in the future through an Elon Musk type and Peter Thiel type of quadrant? We will see!

Hope you found this post interesting and should encourage you to check up on your current R&D environment. Maybe it needs a bit more of Edi-Pasteuring.

Greetings and till next time

Herwig

Literature:

[1] Ward Ooms, et.al: Research orientation and agglomeration: Can every region become a Silicon Valley? (2015)

Why the New Economy reshapes the plastics industry and what you need to know for helping reshaping it too!

First things first: What is the New Economy thinking?

As already stated in one my previous blog posts, the New Economy, also called the Next Economy, follows one central rule: “The winner takes it all” – the first person to come up with an innovative solution gets the biggest market share (around 70%). The New Economy will affect all markets and industries including the plastics industry. The Internet of Things and Industry 4.0 starts to take off at industrial scale. In the next 5 years, maybe even earlier, decisions will be made and the gap between successful and failed businesses will be significantly increased.

My suggestions on how to accelerate the New Economy thinking in the plastics industry:

Orientate on the key principles of 4 major personalities who have established complete new systems and turn around whole industries in the 21^st century:

1) Elon Musk (Founder of Tesla & SpaceX): “It doesn’t matter whatever you are doing needs to be a great product or service”.

It doesn’t matter what the others offer, what you offer needs to be a lot better. For example, when you enter with your product or service an existing market place, you will need to stand out. Elan Musk states that you always have to jump into the customer role and ask: Why would I buy exactly this? You as a customer will buy the trusted brand unless there is a big difference compared to your trusted brand. It can be a price difference (much cheaper) or a value difference (significantly more added value).

There are often intellectual property discussions, which could come along with your product. Here, Elon Musk has an interesting view: “All Our Patent Are Belong To You”

Technology leadership is not defined by patents, which history has repeatedly shown to be small protection indeed against a determined competitor, but rather by the ability of a company to attract and motivate the world’s most talented engineers. We believe that applying the open source philosophy to our patents will strengthen rather than diminish Tesla’s position in this regard (Elon Musk, June 12, 2014).

2) Peter Thiel (Founder PayPal, Investor): “Competition is for losers”.

Straight forward his view on how to build successful businesses in the New Economy. You need to go from zero to one and aim for a monopoly. Your business needs to differentiate itself so much from others that it is not even competing. Important to note is that a world of perfect competition is a world where all the capital gets competed away! A good example which demonstrates the zero to one philosophy is Google: they have no serious competition. Google differentiated itself so strongly from Yahoo and Microsoft Bing that it has been able to hold the monopoly of the digital search engines for the past 13 years, which results in an enormous cash flow.

Part of a successful zero-to-one strategy is to find the secret path. Most companies try to rush through the tiny doors where everybody tries to get through. Maybe, around the corner there is a secret gate which no one is using. Always strive for the secret path.

3) Tim Ferris (Inventor of the 4-hour workweek, 4-hour body and 4-hour chief): “DiSSS formula”.

In the New Economy, adapting your skills in a certain direction or learning new skills may elevate the way to do business. How to do that best? Follow the DiSSS formula to master everything, from learning a language to learn cooking. Tim explains this method by using LEGO blocks [1]:

Deconstruction: "What are the minimal learnable units, the LEGO blocks, I should starting with?"

Selection: "Which 20% of the blocks should I focus on for 80% or more of the outcome I want?"

Sequencing: "In what order should I learn the blocks?"

Stakes: "How do I set up stakes to create real consequences and guarantee I follow the program?"

Apart of DiSSS, from the 4-hour workweek book, I took away 2 other concepts, which can make your daily actions in business easier: The Pareto principle (80% output results from 20% inputs) and the Parkinson law (a task will increase importance and complexity in relation to the time allocated for its completion).

This can help you increasing your productivity by:

1. Apply the Pareto principle to focus on important tasks and then
2. The Parkinson law for shortening your time to important tasks.

4) Simon Sinek (Author of Start with Why): “Why? How? What?”.

Great leaders inspire people from the inside (Asking: Why?) to the outside (Asking: What?), which is represented by the so-called golden circle. The key for motivating people to take on action starts  by stating out why you do certain things and not by explaining the ‘what’ of a task or product. The ‘what’ is always a consequence of your ‘why’. Take as an example the way Nike and Apple communicate.  People follow you, not because they must. They follow you because they identify themselves with your product’s philosophy. This is explained by Simon with the law of diffusion of innovation.

-The first 2.5% of our population are our innovators.

-The next 13.5% of our population are our early adopters.

-The next 34% are our early majority, our late majority (34%) and our laggards (16%).

For having a mass-market success you need to achieve the tipping point between 15 and 18 % market penetration. Then, the market starts to tip and your idea will be accepted by the majority or simple put:

“People don't buy what you do; they buy why you do it and what you do simply proves what you believe. (Simon Sinek)”

The unwritten rules of the New Economy will change the way how we do business, how we innovate and how we live. The best way of understanding the ideas around the aforementioned people is to ob­serve your direct environment. You will find already influencing changes in most disciplines of plastics processing, production and developments.

Further remarks on this topic:

To follow the ideas of the New Economy, we have to start living in 2016 and not applying concepts and methods from e.g. 2008. You can observe that strongly in marketing: companies spend millions of their budget on printed advertisements, however, nowadays you need to directly hit the customer within seconds (online)!!

Silicon Valley in the U.S. has a clear vision and answers on how we will live in coming years. They will influence the world population over their business monopolies. Only few people will decide on how millions of people will live. This way of thinking is imperialistic dominated. The United States of America is good prepared for changes to come up, since most of these monopolies have originated there. The European Union has no answer to most of the questions which will come up in the next years.

Main areas of strong vision for the future are:

• Our health: we will become older than 100 years. The medical treatment will shift from passive (going to doctor for treatment) to strongly preventive (measuring and recognizing upcoming diseases). Gen engineering will also be on the way.
• The way of transportation will change - self-driving cars are finding their way in the market.
• Artificial intelligence: the machines learn behaviors on their own and replace the human beings in certain jobs which can cause an increase in unemployment up to 40-50%.

All the aforementioned areas are chances for the plastics industry to deliver solutions. The most important assets of the New Economy are people with their ideas and how we spend our time. Time needs to be seen as the new currency. You need to be open for business opportunities 24/7. Share this post and till next time!

Greetings,

Herwig


Literature:


[1] http://uk.businessinsider.com/tim-ferriss-disss-system-to-learn-anything-2015-3?r=US&IR=T