Medical Plastics News editor Laura Hughes met with Frank Dilly, managing director, and Calvin Pendorf, head of engineering, both from SIMTEC Silicone Parts to talk about the recent addition of their new class 8 cleanroom.
SIMTEC class themselves as early pioneers in the liquid silicone rubber (LSR) injection moulding industry, following their establishment in 2001 in Madison, Wisconsin.
They specialise in high volume, and highly automated LSR injection moulding, LSR over-moulding, LSR two-shot and multi-shot moulding, and also now hygienic class 8 cleanroom production.
The company also offer made-to-order solutions for customers within the life science, automotive, consumer, sanitary and building-technology industries.
In 2013, SIMTEC moved location to South Florida, whilst maintaining many of their core technical team in the process. The company went on to join European based Rico Group, an established group of highly qualified LSR solutions providers in 2016. Simtec believe this partnership with the Rico Group has led to many advantages for the company including the strengthening of their resources and the expansion of their global footprint.
SIMTEC claim that one of its key distinguishing factors is its true two-shot moulding technology. What do you mean by the term ‘true two-shot’?
Two-shot moulding has previously been used to refer to processes in which the two components are moulded in different machines. However, we believe it is critical to mould both the plastic and silicone in one machine with two injection units.
In true two-shot moulding, two substrates (such as LSR and thermoplastic or LSR and LSR) are moulded in the same machine at the same time. The result is an integrated, multi-substrate, multi-functional component with a strong bond.
We believe that the advantages of true two-shot moulding for customers include:
- Eliminating the need, costs and time associated with secondary steps (such as assembly)
- Material savings (sealing surface only – no material waste)
- Secure placement
- Components with complex part geometries
Well-known as a LSR injection moulding specialist, why did SIMTEC decide to invest in a cleanroom?
There were two main reasons for this investment - the first being that SIMTEC had already held the ISO 13484 certification for years, therefore taking the necessary steps to meet ISO certified cleanroom standards felt like an attainable logical next step. Additionally, we already had a conducive environment and culture, and our facility is new and exceptionally clean. Our production is also highly automated with very minimal human touch or interference.
The second reason for the cleanroom investment was in response to the demand from our life science customers.
Dilly was previously quoted saying: “Medical device OEMs like our highly automated technology and requested we add a cleanroom to our production.”
How did you achieve the cleanroom you have today?
Our first step was to talk to our customers to determine the hygienic requirements needed for the present and foreseeable future.
We next explored the ISO classifications applicable and the requirements.
To establish a benchmark from which to devise our own plan, we visited experienced cleanroom operators and builders in the United States and Europe, and our sister company, Silcoplast in Switzerland - an experienced, high quality cleanroom moulder.
We believe that LSR is more clean than other elastomers and thermoplastics. As LSR is a liquid, it is received and hydraulically pumped into moulding machines from containers called drum kits. This means that no dust is generated, unlike many other materials where this dust occurs.
We also believe our tooling technology is advantageous as we are always aiming for direct gating whenever possible and thus, excluding secondary steps (e.g. de-flashing, die-cutting or cleaning).
“Once we established our requirements, we chose a supplier and put together a plan to build a class 8 cleanroom on our existing production floor with a unique hybrid design, and a plan that would facilitate quick expansion as needed”, noted Calvin Pendorf, who spearheaded the cleanroom project.
Your cleanroom has been described as a ‘smart design’ - why is that?
Our cleanroom has a somewhat unique layout. Typically, in most cleanrooms all equipment and activities are contained within the cleanroom; our layout is different. We wanted to minimise contaminants as much as possible, by reducing traffic in and out of the cleanroom and eliminating as many of the sources of particles as we could.
Maximum number of particles in air by ISO class of cleanroom
In our cleanroom layout, material staging takes place outside the cleanroom. Tool setups and changes take place in a separate enclosure attached to the cleanroom with a pass-through. The rest of the moulding machine remains outside the cleanroom. Parts produced in our fully-automated one-shot and two-shot lines are robotically removed and transported within a filtered and pressure-controlled enclosure into the cleanroom for inspection, post-curing and bagging.
Recommended air changes and ceiling coverage by ISO class of cleanroom
Source: Cleanairproducts.com
Have you experienced any growth opportunities as a result of your expanded capabilities?
Yes, we are confident we are competitive in terms of our technology level, accuracy and performance in this space. As a result, we have been fortunate enough already to have increased opportunities with many well-known medical device manufacturers in the United States.
Pendorf will be a speaker at the upcoming 2019 LSR conference in Schaumburg, United States on 9th to 12th September. Here, Pendorf will discuss the best way to set up a cleanroom.