Saturday, 23 December 2017

5 Software Tools To Estimate The Production Economics In Injection Moulding

Hello and welcome to this blog post on 5 tools to estimate production economics in injection moulding.  A series production of an injection moulding business may comprise thousands of produced parts monthly. Therefore, optimizing costs per piece can substantially impact the business financial outcome. Based upon literature research [1] and my own experience, I have compiled 5 injection moulding software tools to improve your production economics.

1. Injection Molding Cycle Time Estimator:
It is mainly used to estimate the time of an injection moulding cycle, which in turn will support a better production planning.
Features: The estimation takes into consideration the resin type. Furthermore, it allows a machine to set override for temperatures. For cooling, two types of estimation methods are available: centerline and average cooling of the wall. It has an error checking included and an easy Windows Forms interface. The software is freeware.

2. ProMax-One™ Plastic Part Cost Estimator by InjectNet:
This program calculates the total cost per part offering a cost breakdown where individual cost positions are detailed.
Features: The following boundary conditions are used: material, labour, mould cost, machinery, maintenance, cavity information and general project information (timeframe, etc.). This software is in its freeware version more complete than the Injection Molding Cycle Time Estimator from 1).

3. CostMate® by UL Prospector
CostMate® is part of UL Prospector plastics search engine.
Features: It can accurately estimate the cost of producing an injection moulded part and it considers costs associated to shipping as well as packing.  Additionally, it can generate a report of material price, machine, secondary costs, profit and total quote. Its basic version is free.

4. DFM Concurrent Costing® by Boothroyd Dewhurst Inc.
This software is mainly intended for the design of the part stage.  
Features: You can import your part geometry and you can customize the cost estimate inputs. Furthermore, you can import variables from your own injection moulding machine. Geometry calculations can be done within the program too. You can compare alternative production processes and materials for manufacturing your desired part. This is a commercial paid software.

5. CalcMaster® by Schoenberg & Partners
This commercial software is a cost estimator and a good design assistant too.
Features: CalcMaster® estimates the most economical number of cavities for your mould. Furthermore, it is able to take the all over project hours cost (design and manufacturing) into account.

Overarching, the commercial software solutions, DFM Concurrent Costing and CalcMaster, are most comprehensive regarding decision making on the final part costs. Nevertheless, ProMax-One™ can be a good choice to start with before investing into a commercial software package. It offers already the calculation of several parameters such as cavity data, project timeframe and material data.

Enjoy trying out some of the programs and thanks for reading!

Herwig Juster

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.
New to my Find Out About Plastics Blog – check out the start here section
Polymer Material Selection (PoMS) for Electric Vehicles (xEVs) - check out my new online course

[1] M.A. Selles, Analysis and review of different tools to calculate the production economics in injection molding, The 7th International Conference Interdisciplinarity in Engineering (INTER-ENG 2013)

Thursday, 30 November 2017

High performance polymers used in children buggies

Weight reduction to save energy and costs has been and will continue to be a constant topic of interest in the aircraft and automotive industries. In this regard, much has been done toward replacement of metals especially the heaviest ones by lighter materials still able to fulfill application demands. Nevertheless, there are other industries where metal replacement and consequent weight reduction can also make life easier especially when you have children. I am talking about children buggies. Most buggies have between 8.5 kg and 10 kg. Heaviest ones may range from 12 kg to 17 kg in total weight (frame plus seat). The weight is a result of using aluminum, which is already among the lightest metal materials (2700 kg/m3). Furthermore, it is naturally resistant to corrosion. Is it still possible to make buggies lighter while keeping their current application suitability? Yes, by using high performance polymers.
Following, I will present you a commercial example of the company Quinny that won the 2014 Red Dot ‘Best of the Best’ Award for their 5 kg Yezz buggy [1,2].
5 kg Yezz buggy using PARA frames [1,2]

Why is it only 5 kg heavy and still a high-end performer?
The frame of the buggy is made of several frame parts using the high performance polymer, polyarylamide, commonly known as PARA, reinforced with glass fibers (50 wt%) [3]. The weight reduction is achieved by the reduced density of PARA, 1600 kg/m3. The high-end performance comparable to metal is achieved by the aromatic amide macromolecular structure of PARA, which provides this polymer with inherent high stiffness and strength. For instances, the tensile modulus of PARA can reach values up to 23 GPa at 20°C.

In terms of processing, a major added value of PARA is that it can be loaded up to 60%wt with glass fibers for reinforcement purposes [4] without this to be noticed in the moulded part. The latter will still exhibit a smooth surface with no evidence of contained glass fibers. Such surface allows excellent painting and/or metallization. Additionally, PARA has good flow properties at melting temperatures, which allow the moulding of parts as thin as 0.5 mm. For these reasons, PARA can be a suitable material when complex parts requiring high stiffness in combination with superior surface quality are needed. Accordingly, premium automotive interiors could be of interest.
Next time when you’re are looking for a buggy keep in mind that there are lightweight solutions to make travelling activities with your children easier.

Thanks for reading!
Herwig Juster

New to my Find Out About Plastics Blog – check out the start here section.


Tuesday, 31 October 2017

How to Calculate the Residence Time in Plastics Injection Moulding [incl. online calculation tool]

The term residence time in injection moulding operations refers to the time that a plastic pellet takes from entering the injection moulding barrel until entering the injection mould. It relates to the amount of polymer material present in the cylinder of the injection unit, the shot weight and the total cycle time. Often, residence time is also referred to as Hold-Up Time (HUT).

Melting of plastics for processing is usually attained by bringing the plastics over a certain temperature, i.e., glass transition temperature for amorphous thermoplastic polymers and glass transition temperature as well as crystalline melting temperature for semi-crystalline thermoplastic polymers. For both types of thermoplastics longer than necessary heat exposure, especially in the presence of oxygen (air), may induce chemical degradation. Therefore, the residence time in injection moulding at polymer-sensitive melt temperatures needs to be optimal. In this context, residence time is especially important for polymers such as, for example, PVC, POM, ABS, PBT and PET.

Melt temperatures have to be chosen in a way that the material’s thermal stability during processing is ensured [1, 2]. Guidance about optimal residence time and residence time for different polymers is given by material manufacturers in processing and design guides.  In practice, tools for accurately calculating the melt residence time depending on the utilized machine and processing conditions are usually not available. This prevents processing engineers from making quick process assessments. For this reason, I have created a demo-sheet to calculate the residence time of your injection moulding operation. This can be used online or downloaded. The calculation is based on the formula below [3].

Formula for calculating the residence time in injection moulding

Here, number 8 represents the volume of the molten polymer in the barrel. This is the ratio between flight height and screw length, which for most injection moulding machines is approximately 8. Part A gives the number of shots in the barrel and Part B represents the cycle time to produce the part.

Finally, keeping the residence time at an optimum level will help you keeping materials’ degradation to a minimum and, consequently, the mechanical properties of your final moulded part to a maximum.

Successful moulding and thanks for reading!

Till next time!
Greetings, Herwig
New to my Find Out About Plastics Blog - check out my start here section

[2] GE Plastics - Injection Moulding Guide
[3] Christoph Jaroschek - Spritzgießen für Praktiker


Monday, 25 September 2017

Polymeric Materials for Automotive Applications - Why Plastics in Cars matter [Infographic]

In the past 40 years plastic materials incrementally found their way into automobiles. The applications using polymeric materials and composites indicate further growth in the future  as well [1]. The utilization of plastics supports weight reduction and fuel economy. However, this is not the only reason plastics are used. The design freedom associated to plastics allows new approaches in the design of parts and lead to increased innovation such as the integration of different parts and material combinations. Additionally, plastic parts show minimum corrosion when compared with metals which improve vehicle lifetime. Last but not least, plastics enhance vehicle safety, comfort and  and are recyclable as well. 

The overall numbers are quite impressive: the average global plastic amount used in cars is 100 kg. A range of different polymers is applied to ensure functions such as low fuel consumption, appearance and freedom in design. Fuel usage, for example, can be reduced by 5% to 7% when the car weight is reduced by 10% [2].  And this is realized by polymeric applications. 

Now enough of the features and benefits. To give you an entertaining view on this topic, I created an infographic which you can find below. It will uncover which plastics are used for which parts in the car. I hope you can recognize some of the parts when entering your car next time. 

Enjoy and till next time!

You can find all of my infographics also here at slideshare.

Thanks for reading!
Best regards,

[2] A. Patil: An overview of Polymeric Materials for Automotive Applications, Materials Today: Proceedings 4 (2017) 3807-3815 

Monday, 28 August 2017

Shu-Ha-Ri: An essay on innovation in plastics industry

The new economy is disrupting one industry after the other. With its customers being disrupted the plastics industry is no exception. Industries are pushed to adapt and in many cases even shift their core competencies in order to survive. A case in point is the ongoing shift from combustion engine expertise to battery technology expertise in the automotive industry [1]. Every disruption brings along opportunities for implementing new plastic solutions.

What are the ways in which a business organization must change to take up hard problems and offer unique solutions in a VUCA (Volatile, Uncertain, Complex and Ambiguous) world? First, business development must be customer-focused, i.e., customer is the center for innovation. This means a paradigm shift from market push to customer pull is necessary. Secondly, innovation concepts must be pre-defined. Only in this way, organizations can work effectively toward it.
Shu-Ha-Ri is a Japanese concept used in martial arts [2]. In my opinion, this may be applied in the context of innovation as well and help us to gain ground in the new economy environment. Following, I will explain the concept of Shu-Ha-Ri at first through a cooking example [1, 2]. Thereafter, I will make the bridge from the mentioned example to the plastics industry.
  • Shu ("protect", "obey"): This is the beginner’s stage. In this stage, you start cooking according to the recipe and you keep yourself strictly to the recipe. There are no modifications. Convenience food manufacturers and fast food services are in those categories as industrial examples.
    Translation to the plastics industry: For instances, concerning injection moulding: the machine operator is acquainted with the machine and the handling of the moulding process. The focus is mainly on how to excel the task in a mechanistic manner, e.g. proper injection moulding of thermoplastic resins.
  • Ha ("detach", "digress"): At this level, you still follow the recipe for cooking, but you start adding your sense of flavor. This can mean that you add a bit more salt and pepper to better fit the taste of the whole meal.
    Translation to the plastics industry: The above-described machine operator starts learning the underlying principles behind the injection moulding process and is able to combine knowledge from the three M’s in plastics processing: Material, Machine and Mould. As a result, he/she is able to set up and adjust the running process.
  • Ri ("leave", "separate"): This is basically reinventing the way you cook a certain meal or even one step further to invent complete new ways of making new meals. To put it simple, with Ri you are the rule and you are able to seek unique solutions to hard problems or re-invent the way we do things. Translation to the plastics industry: The machine operator starts creating his/her own ways of processing and incorporates that in his/her daily operations. 

  • Shu-Ha-Ri in plastics industry:
    The basic idea is that people in a (plastics) technology organization have to go through the different stages of Shu-Ha-Ri to be able to achieve excellence in innovation. Their mind- and skills set need to reach the Ri-level.
    For too long, the majority of big companies shaped their departments toward Shu. This resulted in process thinking, performance self-assessment and outsourcing of services. Several departments made themselves redundant, which is highly beneficial for commodity type of business. Reduction of costs is the major upside of such systems, while major downsides include brain and skill drain. Because core competencies were more and more outsourced to Tiers [2], organizations struggle now to bring Ri-type of innovations to the market.
    Now, in the times of new economy, we need more Ri skillset to integrate software, hardware and design into excellent products. The expectation of business leadership to transform Shu level stuff (‘cooking according the recipe’) to Ri innovators (‘re-invent the way of cooking’) has several challenges. Take plastic resin formulation as an example: Changing a resin formulation will result in Shu- and Ha-type of innovation. The base feedstocks are well known and available mostly in huge quantities. Exchanging certain parts of the recipe can, thus save costs.   There is no new market, nor new product involved. Conversely, for Ri-innovation, the business outcome is not clearly defined, meaning that there is no business case where you can be 200% sure that the numbers will be hit. This means that people need to have more an entrepreneurial edge then a classic business economics background. In Shu and Ha, business cases make sense and are accurate, since experience exist (from R&D, procurement over to supply chain). This is the reason why this way of “innovation” is preferred, resulting in efficiency innovation (e.g. moving production to cheaper locations) and good enough downgrade innovations (e.g. hardcover book to paperback only).

    I would like to end this post with an example in plastics business, which shows a Ri behavior:
    The 3M Company implemented a three-step process [3], which ensured them fruitful innovations over the years. The designated functions of the steps are “Scouts,” “Entrepreneurs” and “Implementers”. The scouts are the project hunters. Their job is to identify hard problems which are worth solving. The Entrepreneurs help then to figure out how to capitalize on the opportunities. Those can be manufacturing experts, engineering and other functional experts. They carve out a functional prototype. Once all the product related investigations are done, Implementers take over. Their job is to get the new product ready for commercialization. Scouts, Entrepreneurs and Implementers have a strong Ri-mindset and are able to think outside the classic ways because they know that is the only way to solve hard problems! It is a step away of ‘what’s in it for me’ and focusing on the greater vision of improving everyone’s life.

    Thank you for reading and successful innovating!


    P.S. New to my blog – check out the start here section
     [1] Prof. Dr. Gunter Dueck – Der Prozess ist der Innovation ihr Tod, Podcast Markenrebell, June 2017

    Tuesday, 20 June 2017

    Strategic business development: A lesson learned from the automotive pioneers, Henry Ford, DuPont and General Motors

    In nowadays business world, we often discuss and talk a lot about how the “competitor can be shaped”. In other words, how can we put our businesses ahead in the game? However, often the opposite is forgotten: it is also critical that your competitor does not shape our businesses!
    In this blog post, I give you an example that I heard back at university. I hope that you will find it useful and will keep it in mind in your next strategic steps.
    Henry Ford, the founder of the Ford Motor Company, was an impressive man, ahead of time entrepreneur, respected by a broad audience. By introducing the assembly-line concept, which produced the Model T, the selling numbers increased from 6,000 cars in 1909 to 200,000 in 1914. Applying the economy of scale, price dropped from $1,000 to $260 per car by 1924. Shifting to the assembly-line production required the cars to be colored black, because this color would dry faster than other colors. Therefore, every car manufacturer used it. Most of us know Ford’s statement:

    “You can have any color car you want, as long as it’s black”

    In the beginning of the 1920’s DuPont introduced a quick-drying paint [1]. General Motors adapted this paint and following a multi-product strategy General Motors was able to introduce new car models with different colors every year. Ford’s single-product strategy could not withstand this and by 1927 General Motors took the lead in market share. Ford could never regain this position. Ford “got shaped by the competitor”, because he kept his concept for success too long. As a result, upcoming innovation took over.

    To summarize it by Sun Tzu:
    “Therefore, when I have won a victory I do not repeat my tactics but respond to circumstances in an infinite variety of ways”. (VI.26)

    Greetings and till next time!

    P.S.  New to my blog – check out my ‘start here’ section.

    [1] Mark McNeilly: Sun Tzu and the art of business

    Thursday, 27 April 2017

    My Top 5 Commodity Plastics For Medical Device Applications – Part 5: COC

    Welcome back to the blog series about “My top 5 commodity plastics for medical device applications”. This is part 5 – Cyclo Olefin Coploymers (COC).
    Here you can jump to part 1 – PVC, part 2 – PE, part 3: PP and part 4: PS.
    Nr. 5 – Cyclo Olefin Copolymers (COCs)
    Cyclo Olefin Copolymers (COCs) were introduced in the last decades and found their home in medical device applications in a significant way. They are amorphous and transparent copolymers made by cyclo olefins (norbornene-based) and linear olefins (ethylene-based). The typical chemical structure of such copolymers is shown in Figure 1.
    What makes them so ‘special’?
    It is the combination of high transparency with high impact behavior together with superior moisture barrier properties which results in excellent stability in terms of dimensions and processing. Furthermore, COCs exhibit stronger shatter resistance than glass and their thermal resistance is significantly improved in relation to polyethylene and polypropylene. These also show a better transmittance at visible and near-ultraviolet wavelengths. Their birefringence is lower than that of polystyrene and polycarbonate.

    Figure 1: Chemical structure of Cyclo Olefin Coploymers (COCs)
    The superior properties of COCs are very much due to the presence of the norbornene unit and its bridged-ring structure which prevents crystallization. In addition, adjustment of the norbornene content allows tailoring of the thermal properties with higher content leading to higher heat resistance.
    A comparison in properties, processing and compounding can be found in Table 1 [1].
    Table 1: Characteristics, processing and compounding of Cyclo Olefin Coploymers (COCs)
    How do COCs perform in terms of sterilization?
    Sterilization of COC based applications can be done by using gamma radiation and ethylene oxide. Depending on the amount of norbornene, copolymers will have a higher glass transition temperature which makes them suitable for steam and dry heat sterilization.
    What about biocompatibility?
    COCs have a low amount of extractables which give them excellent biocompatibility. There are COC grades available which fulfill the United States Pharmacopeia (USP) Class VI and/or ISO 10993.
    Where is COC used in medical device applications?
    COCs rose to fame in healthcare through their usage in blister packs. COCs proved particularly suitable for this application due to their good film extrusion, thermoformability together with good barrier properties and low moisture uptake. Figure 2 shows a cross section of a blister film which uses COCs [2]. This is a chlorine- and fluorine-free film which represents a good alternative to PVC-based films.
    Figure 2: Cross-section of a COC based blister film

    In general, blister packs consist of two components: a thermoformable film, which composes the cavity transporting the pharmaceutical product, and a lidding made of aluminum or plastic that seals the cavities after filling.
    Apart of blaster packs, COC is used for syringes, vials and ampoules, petri dishes and specialized labware. Furthermore, you can find COCs in needleless injectors, injector pens, and inhalers.
    Table 2:  Examples of medical applications using COCs adapted from [1]

    Where to get COC for your medical device applications?
    Table 3 lists the suppliers for COCs. 
    Table 3: Suppliers of COCs [1]
    Thanks for reading! Have a beautiful day & till next time!

    P.S.S.  New to my blog – check out my ‘start here’ section.
    [1] Vinny R. Sastri: Plastics in Medical Devices, 2014
    [2] Amcor – Polybar®:

    Tuesday, 25 April 2017

    My Top 5 Commodity Plastics for Medical Device Applications – Part 4: PS

    Welcome back to the blog series ”My top 5 commodity plastics for medical device applications”. This is part 4 – Polystyrene (PS).
    Here you can jump to part 1 –PVC, part 2 – PE and part 3: PP.
    Nr. 4 – Polystyrene (PS)
    Polystyrene has long found its way in medical device applications and is widely used. PS is an amorphous polymer and is available in two forms: crystal clear polystyrene also referred to as General Purpose Polystyrene (GPPS) and as High Impact Polystyrene (HIPS).
    HIPS is usually modified using polybutadiene elastomers. Depending on the added amount a high-impact grade (6-12% elastomers) or a medium-impact grade (2-5% elastomers) may be obtained.
    A comparison in properties of GPPS and HIPS can be found in Table 1 [1].
    Table 1: overview properties of GPPS and HIPS
    Similarly to PP, PS can be found in three different structures: atactic (A-PS), isotactic (I-PS) and syndiotactic (S-PS). The A-PS is the most commercially available structure followed by S-PS. In applications with rather demanding specifications S-PS is usually preferred due to its superior properties i.e. high melting point (270°C), good chemical resistance and very low dielectric constant. Furthermore, S-PS has high flow capability which facilitates processing and enables thin-wall applications. Virgin S-PS is brittle. Thus, when toughness is required S-PS is usually reinforced with glass or alloyed with other polymers.  S-PS is produced in a continuous polymerization process using metallocene-based catalysts similarly to polyolefins.
    How does PS perform in terms of sterilization?
    Steam and autoclave sterilization are not applicable to PS due to its low heat distortion temperatures (85 °C at 1.85 MPa / 95 °C at 0.46 MPa). These will cause warp and disfigure. On the other hand, PS can be sterilized by Ethylene Oxide. This is valid for both types – GPPS and HIPS. PS shows a great stability to gamma radiation due to its high aromatic content. The aromatic ring has free electron clouds which are able to absorb the radiation inhibiting the generation of free radicals. No significant shift in color is generally observed either.  Therefore, PS can also be sterilized by irradiation.
    What about biocompatibility?
    PS is usually not used for applications where biocompatibility is required. However, there are biocompatible grades available from specific manufactures [2]. These allow using the versatility of polystyrene under the ISO 10993 compliance of the medical market.
    Where is PS used in medical device applications?
    GPPS can be processed over injection moulding leading to applications in labware, diagnostic equipment (e.g. petri dishes, test tubes and IVD products), and device components. GPPS processed by extrusion is used for packaging. As for HIPS is rather used in trays, bottles, containers, and medical components. Generally, HIPS is preferred over GPPS when impact resistance is of greater importance. Table 2 gives an overview of medical applications using PS. Since the properties of PP have been improving over the last decade, this becomes more and more competitive with PS, especially due to the relatively lower cost of PP.

    Table 2:  Examples of applications using PS adapted from [1]
    Where to get PS for your medical device applications?
    Table 3 lists suppliers for GPPS and HIPS.
      Table 3: Suppliers of PS [1]
    Table 3: Suppliers of PS [1]
    Thanks for reading! Have a beautiful day & till part 5: COC!
    P.S. New to my blog – check out my ‘start here’ section.
    1] Vinny R. Sastri: Plastics in Medical Devices, 2014
    [2] Trinseo - STYRON™ 2678 MED Polystyrene Resin: